UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, DC 20460 

OFFICE OF CHEMICAL SAFETY AND POLLUTION PREVENTION 

PC Code: 12893 l 

DP Barcode :422305 

Date: March 24, 2016 

MEMORANDUM 

Subject: 

To: 

From: 

Through: 

Addendum to Dicamba Diglycolamine (DGA) Salt and its Degradate, 3,6-

dichlorosalicylic acid (DCSA) Section 3 Risk Assessment: Refined Endangered 

Species Assessment for Proposed New Uses on Herbicide-Tolerant Cotton and 

Soybean in 7 U.S. States (Alabama, Georgia, Kentucky, Michigan, North 

Carolina, South Carolina, and Texas) 

Grant Rowland, Risk Manager Reviewer 

Kathryn Montague, Product Manager Team 23 

Dan Kenny, Branch Chief 

Herbicide Branch 

Pesticide Registration Division (7505P) 

Office of Pesticide Programs 

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E

Mic

lizabeth 

hael Wagman, 

Donovan, 

B

Biologist 

iologist '

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Monica Wait, Risk Assessment Process Leader ~ W~ °3 / 2-1..\-/l b 

Environn1ental Risk Branch 6 

Environmental Fate and Effects Division (7507P) 

Office of Pesticide Programs ~ 

Mark Corbin, Branch Chief r ~ J-1,~ -\ {, 

Environmental Risk Branch 6 \J.J' 

Environmental Fate and Effects Division (7507P) 

Office of Pesticide Programs 

Prior to conducting this refined Endangered Species Assessment, the Environmental Fate and 

Effects Division (EFED) performed a screening level ecological risk assessment for a Federal 
2

action involving proposed new uses of the diglycolamine salt of dicamba (dicamba DGA) on 

dicamba herbicide-tolerant soybean on March 8, 2011 (DP 378444); an amendment to the 

assessment was issued on May 20, 2014 (DP 404138, 404806, 405887, 410802, and 411382). 

Concurrent with this refined Endangered Species Assessment, a Section 3 New Use dicamba 

DGA salt on dicamba-tolerant cotton screening-level assessment (DP 404823) and a subsequent 

addendum (DP 426789) that addresses multiple issues (spray drift buffers, runoff, risk to 

terrestrial invertebrates and updated mammalian toxicological endpoints for parent dicamba and 

its degradate, DCSA) have been finalized. In the screening level risk assessment, potential direct 

risk concerns could not be excluded for:

• mammals (chronic, from the soybean use only, due to residues from dicamba’s 

metabolite, DCSA, rather than from parent dicamba); 

• birds (acute from parent dicamba for both soybean and cotton uses; chronic from DCSA 

residues only in soybean but not in cotton), considered surrogates for reptiles, and 

terrestrial-phase amphibians; and

• terrestrial plants (soybean and cotton uses)

In the screening level risk assessments, indirect effect risk concerns for all taxa were possible for 

any species that have dependencies (e.g., food, shelter, and habitat) on mammals, birds, reptiles, 

terrestrial-phase amphibians, or terrestrial plants. Additionally, the screening level assessments

showed that direct risk concerns were unlikely (i.e. levels of concern were not exceeded) for: 

• mammals (acute) and (chronic—for the cotton use only); 

• birds, reptiles, and terrestrial-phase amphibians (chronic from parent dicamba or DCSA 

degradate from use on cotton); 

• terrestrial insects (acute and chronic); 

• freshwater fish (acute and chronic);

• aquatic-phase amphibians (acute and chronic); 

• estuarine/marine fish (acute and chronic); 

• freshwater invertebrates (acute and chronic); estuarine/marine invertebrates (acute and 

chronic); and 

• aquatic plants1

EPA has a specific process based on sound science that it follows when assessing risks to listed 

species for pesticides like dicamba that will be used on seeds that have been genetically modified 

to be tolerant to the pesticide. The Agency begins with a screening level assessment that 

includesa basic ecological risk assessment based on its 2004 Overview of the Ecological Risk 

 1 The listed species LOC was exceeded for non-vascular aquatic plants, however there are no listed 

species of this taxa.
3

Assessment Process document. [USEPA, 2004, available at 

http://www.epa.gov/oppfead1/endanger/litstatus/riskasses.htm]. That assessment uses broad 

default assumptions to establish estimated environmental concentrations of particular pesticides. 

If the screening level assessment results in a determination that no levels of concern are 

exceeded, EPA concludes its analysis. On the other hand, where the screening level assessment 

does not rule out potential effects (exceedances of the level of concern) based on the broad 

default assumptions, EPA then uses increasingly specific methods and exposure models to refine 

its estimated environmental concentrations. At each screening step, EPA compares the more 

refined exposures to the toxicity of the pesticide active ingredient to determine whether the 

pesticide exceeds levels of concern established for listed aquatic and terrestrial species. EPA 

determines that there is “no effect” on listed species if, at any step in the screening level 

assessment, no levels of concern are exceeded. If, after performing all of the steps in the 

screening level assessment, a pesticide still exceeds the Agency’s levels of concern for listed 

species, EPA then conducts a species-specific refined assessment to make effects determinations 

for individual listed species. The refined assessment, unlike the screening level assessment, 

takes account of species’ habitats and behaviors to determine whether any listed species may be 

affected by use of the pesticide. 

The screening level ecological risk assessment generates a series of taxonomic (e.g., mammals, 

birds, fish, etc.) risk quotients (RQs) that are the ratio of estimated exposures to acute and 

chronic effects endpoints. These RQs are then compared to EPA established levels of concern 

(LOCs) to determine if risks to any taxonomic group are of concern. The LOCs address risks for 

both acute and chronic effects. Acute effects LOCs range from 0.05 for aquatic animals that are 

Federally-listed threatened or endangered species (listed species) to 0.5 for aquatic non-listed 

animal species and 0.1 to 0.5 for terrestrial animals for listed and non-listed species. The LOC 

for chronic effects for all animal taxa (listed and non-listed) is 1. Plant risks are handled in a 

similar manner, but with different toxicity thresholds (NOAEC/EC05 and EC25, respectively) used 

in RQ calculation for listed and non-listed species and an LOC of 1 used to interpret the RQ. 

When a given taxonomic RQ exceeds either the acute or chronic LOC a concern for direct toxic 

effects is identified for that particular taxon. If RQs fall below the LOC, a no effect 

determination is identified for the corresponding taxon.

The purpose of this document is to explain the refined risk assessment conducted for Federallylisted threatened or endangered (listed) species that could potentially be impacted by this 

pesticide registration. The refined assessment was conducted based on the 2004 Overview 

document, as discussed above. The assessment of risks to listed species posed by the use of 

Dicamba DGA has been conducted in phases covering a specific set of states, assessing risk to 

all the listed species covered in those states. This assessment covers the endangered species 

analysis for 7 states: Alabama, Georgia, Kentucky, Michigan, North Carolina, South Carolina 

and Texas. Based on EFED’s LOCATES v.2.4.0 database and information from the U.S. Fish 

and Wildlife Service (USFWS), 307 species in the 7 states proposed for registration were 

identified as within the action area (at a preliminary county-wide level of resolution) associated 

with the new herbicide-tolerant soybean and cotton uses. Table 1 presents a summary of this 

assessment. Separate concurrent assessment phases cover the endangered species analysis for 16

states (D416416, 420160, 420159, 420352, 421434, 421723 covering AR, IL, IA, IN, KS, LA, 
4

MN, MS, MO, NE, ND, OH, OK, SD, TN and WI) and 11 states (D425049 covering AZ, CO, 

DE, FL, MD, NM, NJ, NY, PA, VA and WV). 

EPA consulted U.S. Fish and Wildlife Service Recovery Plans to determine whether listed 

species in these states would be expected to occur in an action area encompassing the treated 

soybean and corn fields. The refined assessment was then conducted on those species that could 

not be excluded from the action area. EPA also consulted the recovery plans in the refined 

assessment for additional habitat information and incorporated species biological information 

regarding dietary items (used to model dicamba DGA residues in prey tissue) and body weight 

(used to determine food consumption rates and scale ecotoxicity data from the tested surrogate 

species, the bobwhite quail and rat, to the body weight of the listed species). 

The Environmental Fate and Effects Division (EFED) has completed an endangered species risk 

assessment for Alabama, Georgia, Kentucky, Michigan, North Carolina, South Carolina, and 

Texas in support of registering dicamba diglycolamine (DGA) salt on herbicide-tolerant cotton 

and soybean in these states. Table 1 presents a summary of the assessment.

Table 1. Summary of species effects determinations and critical habitat modification 

determinations for Federally threatened or endangered species in Alabama, Georgia, 

Kentucky, Michigan, North Carolina, South Carolina, and Texas for dicamba DGA use on 

genetically modified cotton and soybeans.

Species Effects Determination Comments

Eskimo Curlew May Affect, Not Likely to 

Adversely Affect

Found in 24 counties (23 in 

Nebraska and 1 in Texas)

All other species (terrestrial 

and aquatic)

No effect None

Critical Habitat Modification Determination Comments

All Critical Habitats (118

species)

No Modification None

Making an Effects Determination

The bullets below outline EFED’s process for making an effects determination for the Federal 

action:

• For listed individuals inside the action area but NOT part of an affected taxa NOR relying on 

the affected taxa for services (involving food, shelter, biological mediated resources 

necessary for survival/reproduction), use of a pesticide would be determined to have NO 

EFFECT.

• For listed individuals outside the action area, use of a pesticide would be determined to have

NO EFFECT.
5

• Listed individuals inside the action area may either fall into the NO EFFECT or MAY 

AFFECT (LIKELY or NOT LIKELY TO ADVERSELY AFFECT) categories depending 

upon their specific biological needs, circumstances of exposure, etc.

• LIKELY or NOT LIKELY TO ADVERSELY AFFECT determinations are made using 

the following criteria:

o Insignificant - The level of the effect cannot be meaningfully related to a “take.”

o Highly Uncertain - The effect is highly unlikely to occur.

o Wholly beneficial - The effects are only good things.

Spray Drift Mitigation

EFED’s refined endangered species risk assessment took into account the spray drift mitigation 

language that has been added to the most recent proposed label submitted by the regitstrant. An 

accounting of federally-listed threatened or endangered species within the 7 states (covered in 

this assessment) proposed for dicamba DGA use on genetically modified cotton and soybeans is 

included in Appendix 1 (307 species). Specifically, the spray drift mitigation language on the 

M1691 Herbicide Supplemental labels for the use dicamba DGA salt on ROUNDUP READY 2 

XTENDTM soybean and BOLLGARD II® XTENDFLEX cotton includes the following 

limitations:

• Specifying the use of a nozzle (Tee Jet® TTI11004) with ASABE S-572 ultra-coarse and 

extremely coarse droplet spectra and a maximum operating pressure of 63 psi. 

• A maximum equipment ground speed of 15 miles per hour and ground boom height of 

24 inches above the target pest or crop canopy.

• Restricting all applications when wind speeds are < 3 mph or > 15 mph and restricting 

applications when wind is blowing towards sensitive areas at > 10 mph. Maintaining use 

of a 110 foot in-field buffer for a 0.5 lb a.i./A application (220 foot in-field buffer for a 1 

lb a.i./A application) when the wind is blowing towards any areas that are not fields in 

crop cultivation, paved areas, or areas covered by buildings and other structures. 

• Applications done in low relative humidity conditions are to use equipment set to 

produce larger droplet spectra to compensate for evaporation. 

• Applications are not be conducted during temperature inversions.

species action 

NO EFFECT

NO EFFECT or

MAY AFFECT 

(LAA/NLAA)

MAY AFFECT
6

• In order to prevent effects to non-target susceptible plants, the label also includes the 

following language: “do not apply under circumstances where spray drift may occur to 

food, forage or other plantings that might be damaged or the crops thereof rendered unfit 

for sale, use or consumption. Avoid contact of herbicide with foliage, green stems, 

exposed non-woody roots of crops, and desirable plants, including beans, cotton, 

flowers, fruit trees, grapes, ornamentals, peas, potato, soybean, sunflower, tobacco, 

tomato, and other broadleaf plants because severe injury or destruction may result, 

including plants in a greenhouse. Applicators are required to ensure that they are aware 

of the proximity to sensitive areas, and to avoid potential adverse effects from the offtarget movement of M1691 Herbicide. The Applicator must survey the application site 

for neighboring sensitive areas prior to application. The applicator also should consult 

sensitive crop registries for locating sensitive areas where available.”

• Finally, in order to prevent unintended damage from the drift of M1691 Herbicide, the 

label says not to apply this product when the wind is blowing towards adjacent 

commercially grown sensitive crops. 

The incorporation of the spray drift mitigation measures into the product labeling as outlined 

above would result in exposure to dicamba DGA from spray drift at a level where effects are 

expected only within the confines of the treated field and so the action area is limited to the 

dicamba DGA treated field. Further, the incorporation of the “susceptible plants” spray drift 

mitigation language on the label is to avoid damage to these plants (including adjacent crops). 

Because the risk assessment interprets the threshold for plant damage concern to be based on the 

most sensitive plant species tested and the screening level ecological risk assessment has 

demonstrated that these plant effects endpoints constitute the most conservative terrestrial 

organism levels of effect, it is concluded that the “susceptible plants” requirement requires a 

level of drift mitigation that would also prevent less sensitive organisms from being exposed at 

levels of concern. Terrestrial species that are not expected to occur on treated fields under the 

provisions of the proposed label are not expected to be directly exposed to dicamba DGA, nor 

are their critical biologically mediated resources expected to be exposed to levels of the herbicide 

above any effects thresholds of concern. Additionally, as indicated in the screening level 

ecological risk assessments for cotton and soybean, no aquatic receptor taxa are of concern for 

drift or runoff exposure (LOCs were not exceeded for aquatic taxa). Consequently, all but 14

of the listed species originally identified as potentially at-risk are determined to be given a 

“no effect” (NE) without further refinement because they are not expected to occur in an 

action area encompassing the treated soybean and cotton fields (Appendix 2). The 

remaining 16 species are assessed using the refinements set forth in the 2004 Overview 

document referred to earlier in this assessment.

Exposure through Runoff

The cotton screening-level risk assessment and the concurrently issued soybean addendum 

characterized risk following exposure to dicamba residues in runoff and found that the predicted 
7

concentrations from modeling were lower than the most sensitive taxa’s endpoint (soybean plant 

height). Combining the predictions of this modeling, the toxicological endpoints and that most 

of the off-site plant community would not experience foliar contact with dicamba DGA in runoff 

sheet flow, EFED concluded that all available lines of evidence supported a “no effects” 

determination for runoff exposure for off-field listed plants for the proposed labeled use of 

dicamba DGA. Additionally, rainfast mitigation on the label would also protect against the risk 

of exposure to listed species off the treated field. 

In addition to the spray drift and runoff mitigation measures contained in the proposed labeling, 

EFED analyzed species-specific biology, dicamba-specific foliar residue data and dicamba 

application timing information in this refined endangered species assessment. An accounting of 

the federally-listed threatened or endangered species within the 7 states proposed for this 

registration showed 307 listed species as potentially at risk (direct or indirect effects) as a result 

of the screening-level assessment (Appendix 1). The spray drift mitigation label language 

cannot preclude listed species being exposed to dicamba DGA salt or DCSA residues on treated 

fields, should a listed species utilize such areas as part of its range and corresponding habitat. Of 

the 307 listed species within the 7 states (AL, GA, KY, MI, NC, SC, and TX) considered part of 

the proposed Federal decision, the following 14 species were reasonably expected to occur on 

soybean and cotton fields, which could potentially be treated with dicamba and therefore could 

not be assumed to be “no effect” solely on the basis of occurrence outside the action area: 

Of these 14 species, a “no effect” determination was reached in the concurrent assessment action 

for 16 states (DP 416416, 420160, 420159, 420352, 421434, 421723 covering AR, IL, IA, IN, 

KS, LA, MN, MS, MO, NE, ND, OH, OK, SD, TN, and WI) for the following species and is 

applicable to the additional seven states in this refined assessment as well:

• American burying beetle (Nicrophorus americanus)

• Gopher tortoise (Gopherus polyphemus)

• Indiana bat (Myotis sodalis)

• Lesser prairie-chicken (Tympanuchus pallidicinctus)

• Louisiana black bear (Ursus americanus luteolus)

• Whooping crane (Grus americana)

This leaves the following species for which the remainder of this document uses species specific 

biological information and dicamba DGA use patterns in more depth to further refine the 

assessment and effects determinations:

 

• Attwater's greater prairie-chicken (Tympanuchus cupido attwateri)

• Eskimo curlew (Numenius borealis)

• Eastern indigo snake (Drymarchon corais couperi)

• Houston toad (Bufo houstonensis)
8

• Virginia big-eared bat (Corynorhinus (=Plecotus) townsendii virginianus)

• Ocelot (Leopardus (Felis) pardalis)

• Gulf Coast jaguarundi (Herpailurus (=Felis) yagouaroundi cacomitli)

• Red wolf (Canis rufus)

Therefore, species specific biological information (e.g., body size, dietary requirements, and 

seasonality) and dicamba DGA use patterns were considered in more depth to further refine the 

assessment and effects determinations. 

This assessment also uses the refined exposure values determined in the cotton screening level 

assessment and the concurrently issued addendum to the soybean screening level risk assessment 

documents compared to the initial exposure estimates from the soybean screening level 

assessment. This ESA assessment also evaluates chronic exposures from DCSA separately from 

the chronic exposure to parent dicamba. Dicamba exposure values were determined from the 

upper bound of the modeled T-REX run for exposures following spray applications based on the 

Kenaga nomogram modified by Fletcher et al (1984), which is based on a large set of actual field 

residue data. Modeled dicamba exposure values were identical between the soybean addendum 

and the cotton screening level risk assessment (since the maximum application rates and 

minimum application intervals are the same). 

Similar modeling of DCSA residues, which are formed inside the tolerant-soybean and tolerantcotton plants through plant metabolism, is not feasible at this time due to a lack of sufficient data 

tracking DCSA residues in plant tissues over time to ascertain degradation rates. Therefore, in 

the soybean addendum and the cotton screening-level risk assessment, EFED used the maximum 

empirical measured DCSA residue concentrations in dicamba-tolerant soybean (61.1 mg/kg 

(ppm) DCSA in broadleaf plants and 0.440 ppm in soybean seeds) and cotton plant tissues (6.29 

ppm DCSA in cotton gin byproducts and 0.27 ppm in undelinted cotton seed) to evaluate chronic 

exposures to DCSA for animals foraging on soybean and cotton plants. Residues in arthropods 

(as a dietary item for birds and mammals consuming insects that have consumed soybean/cotton 

tissues with DCSA residues) were assumed to follow the Kenaga nomogram relationship 

between broadleaf plants and arthropods for spray applications (i.e. arthropod concentrations 

estimated to be approximately 70% of the concentrations in broadleaf plant tissues or 42.5 ppm 

DCSA in arthropods feeding on soybean plants and 4.4 ppm in arthropods feeding on cotton 

plants). The empirical residue data for cotton indicated that chronic exposures of birds and 

mammals to dicamba or DCSA in cotton tissues would not be above any levels of concern. 

Although the concurrently issued soybean addendum indicates that chronic risk to mammals and 

birds was only a concern from DCSA residues in plant/prey tissues and not from residues of 

parent dicamba, since the original soybean screening-level assessment (USEPA, 2011) indicated 

chronic risk to mammals, this assessment presents the estimated exposures and comparisons to 

threshold toxicity values for both dicamba and DCSA for mammals, but evaluates them 

separately since their chronic toxicity and exposure profiles differ greatly. For birds, following 
9

the conclusions of the screening level assessments and the soybean addendum, only acute risk 

from dicamba exposures and chronic risk from DCSA exposures is evaluated.

The following text discusses the lines of evidence and processes that were used to make 

effects determinations for listed species identified as potentially at-risk in the screening 

level assessment. 

Refined ecological risk assessment for the remaining species potentially exposed to dicamba 

residues

For the effects determinations for Attwater’s prairie-chicken, eskimo curlew, Eastern indigo 

snake, Houston toad, Virginia big-eared bat, ocelot, Gulf Coast jaguarundi and red wolf, a 

refined risk assessment approach was used to evaluate additional lines of evidence to determine 

whether the conservative generic assumptions in the screening risk assessment apply to a

particular species of interest (e.g. the Attwater’s prairie-chicken). In the case of the prairiechicken, the refined risk assessment investigated the impacts of more chicken specific data 

related to:

1. Bird size (as the chicken is smaller than the 1000g large bird category used in the 

initial screen)

2. Bird food consumption tailored to:

a. The true weight of the bird

b. Energy requirements of the chicken

c. Improvement on the generic food intake model of the screen to assess energy 

content of the diet and the actual free living energy requirements of a bird the size 

of a chicken

3. Toxicity endpoints were scaled from the weight of the tested surrogate species 

(bobwhite quail) to reflect the comparatively larger actual size of the Attwater’s greater 

prairie chicken

Using the Attwater’s greater prairie chicken as an example to show how EPA made its effects 

determinations, EPA determined that the chicken could be feeding on arthropod prey in treated 

cotton and soybean fields. As stated above, for acute and chronic exposures to dicamba, EPA 

used the upper bound predicted concentrations of dicamba DGA salt found on arthropods from 

T-REX modeling. For chronic exposures to DCSA residues, EPA used the maximum measured 

concentrations found in broadleaf plants, modified by the Kenaga relationship between broadleaf 

plants and arthropods. EPA used the predicted concentrations of dicamba DGA salt found on 

arthropods as its conservative prey analysis consistent with the preliminary risk concerns 

identified in the screening assessment. This prey analysis is consistent with the preliminary risk 

concerns identified in the screening assessments. This analysis is conservative as it assumes 1) 

that 100% of the chicken’s food consumption comes from exposed arthropods and 2) the level of 
10

dicamba DGA residues assumed to be on these prey arthropods is based on the upper bound

Kenaga residues expected for arthropods directly exposed to spray applications of dicamba DGA

and for exposure to DCSA that residues in the arthropod prey item are based on the maximum 

measured values in broadleaf plant tissues modified by the Kenaga relationship between residues 

in arthropods and broadleaf plants following spray applications. EPA determined the field 

metabolic rate of the prairie chicken through the use of a published peer reviewed allometric 

equation that relates bodyweight to energy requirements. From there the mass of prey consumed 

per day is determined by dividing the field metabolic rate (kcal/day) by the energy content of the 

arthropod prey and an assimilation factor that accounts for the ability of birds to absorb that 

energy from the diet. Values were obtained from a published peer reviewed EPA document 

produced by the Office of Research and Development for Agency-wide use in conducting 

ecological risk assessment (USEPA, 1993). The mass of dicamba DGA in the insect diet is 

determined from the T-REX run found in the addendum to the screening-level risk assessment, 

issued concurrently with this risk assessment (USEPA, 2016a) while the mass of DCSA in insect 

diet was assumed to be 42.5 ppm (70% of the maximum measured residues in soybean hay of 

61.1 ppm). The mass of prey consumed per day is then multiplied by the mass of dicamba or 

DCSA in the insect diet to determine the mass of dicamba or DCSA in the chicken’s daily diet in 

mg/day. Then the daily dose that the chicken (considering its bodyweight) receives is 

determined by multiplying the mass of dicamba or DCSA in the daily diet of arthropods 

(assuming that is the only food item) times the mass of prey consumed per day divided by the 

bodyweight of the prairie chicken. Then EPA scaled the acute toxicity endpoint (based on the 

tested surrogate bird species, bobwhite quail’s default weight of 178 grams) to the bodyweight of 

the prairie chicken to determine the acute oral toxicity for the prairie chicken. For exposures to 

DCSA residues, the chronic toxicity endpoint for the mallard (the most sensitive tested species)

was modified by the relationship between the chronic dicamba and DCSA endpoints for rats (a 

17x difference). The acute RQ for dicamba exposures is then calculated by dividing the daily 

dose of dicamba from consuming arthropods by the acute oral toxicity endpoint while the 

chronic RQ is calculated by dividing the daily dose of DCSA by the chronic toxicity endpoint. In 

this case the acute RQ for dicamba was 0.08, which is below the endangered species level of 

concern of 0.1, while the chronic RQ for DCSA was 0.18, which is below the listed and nonlisted species chronic LOC of 1.0. At this point, EPA was able to conclude that dicamba and its 

metabolite DCSA would not have an effect on the Attwater’s greater prairie-chicken. 

Birds

The screening-level assessments showed that birds could be at risk of mortality from acute 

exposures to dicamba DGA on treated fields, but chronic risk was not expected as no chronic 

RQs exceeded the Agency’s LOC (1.0) for chronic risk (USEPA 2011. D378444, p. 15). The 

concurrently issued soybean addendum did indicate that chronic exposures to DCSA residues in 

soybean could be a concern, while the screening level cotton assessment indicated that chronic 

exposures to DCSA residues in cotton would not exceed the Agency’s LOC for chronic risk. 

Therefore, for listed species that could reasonably be expected to occur on treated soybean and 
11

cotton fields, EPA conducted a refined assessment for acute (dicamba only) and chronic (DCSA 

only, and only for soybean) exposures. Of the remaining bird species identified as potentially at 

acute risk in the seven states, two are reasonably expected to occur on treated soybean and cotton 

fields. Therefore, species specific biological information and dicamba DGA use patterns were 

considered in more depth to further refine the assessment and effects determinations for those 

species. 

Attwater’s greater prairie-chicken

Dicamba Acute Effects Assessment

Initial screening level risk assessment results for birds indicated concerns for acute effects. The 

assumptions in the initial screen were adjusted to account for the prairie-chicken’s biology. 

Attwater’s prairie chickens are omnivorous, feeding on a variety of dietary items including seeds 

and pods, insects, broadleaf plants and grasses, with adults feeding primarily on grain, while 

juvenile chickens primarily consume insects. (Lehman, 1941). Therefore, at the time of postemergent dicamba applications (late spring, summer), the most attractive dietary items in 

soybean and cotton fields will be waste grain from weed species and terrestrial invertebrates. As 

a conservative approach, EPA used the modeled upper bound T-REX residues for arthodpods

(which were higher than the modeled residues in grain) to evaluate the potential risk posed by 

dicamba applications at this time. This is considered a conservative approach as modeled 

residues in arthropods are higher than for the other most likely dietary items and 100% of the 

chicken’s diet would be considered to consist of exposed arthropods receiving the upper bound 

Kenaga nomogram dicamba residues from the spray application. Agricultural grains are 

expected to have lower residues than those predicted for arthropods and other dietary items, such 

as broadleaf plant tissues are not expected to constitute as significant a source of the chicken’s 

diet compared to arthropods, for juvenile chickens, or grain for adult chickens (Lehman, 1941). 

A biologically representative refinement to the screening assessment follows:

Field metabolic rate kcal/day = 1.146(772)0.749 = 166.73 kcal/day 

(USEPA 1993, body weight reflects screening assumption for the Attwater’s greater 

prairie-chicken from US FWS Recovery Plan (USFWS, 2010); 

http://ecos.fws.gov/docs/recovery_plan/100426.pdf)

Mass of prey consumed per day = 166.73 kcal/day/(1.7 kcal/g ww X 0.72 AE) = 136.22 

g/day

(1.7 is energy content of prey item from USEPA (1993); 0.72 is assimilation efficiency 

from USEPA 1993, assumption of insect prey from USFWS, 2010, Lehman, 1941)

Mass of dicamba DGA in insect diet 102.99 mg/kg-ww from T-REX run
12

Mass of dicamba DGA in daily diet = 136.22 g/day X 102.99 mg dicamba DGA/kg-ww 

insect prey X 0.001 = 14.03 mg/day

Daily dose in chicken = 14.03 mg dicamba DGA/day/0.772= 18.17 mg/kg-bw/day

Chicken LD50 mg/kg-bw = 188 mg/kg-bw X (772/178)(1.15-1) = 234.28 mg/kg-bw

The RQ for acute effects = 18.17/234.28 = 0.08

An acute RQ of 0.08 does not exceed the acute LOC of 0.1. Consequently, EPA 

makes a “no effect” determination for the Attwater’s greater prairie chicken

DCSA Assessment for Atwater’s greater prairie chicken consuming arthropods that had 

previously consumed soybean forage

EFED considered DCSA residues in arthropods to be the maximum measured DCSA residues 

from broadleaf plants, modified by the Kenaga nomogram relationship between broadleaf plant 

and arthropods as a conservative pesticide load in the prey base. This is considered a 

conservative approach as the estimated residues in arthropods are higher than for the other likely 

dietary items and 100% of the chicken’s diet would be considered to consist of exposed 

arthropods feeding on dicamba-tolerant soybean plants that had the highest measured DCSA 

residues. Agricultural grains are expected to have lower residues than those predicted for 

arthropods and other dietary items, such as broadleaf plant tissues are not expected to constitute 

as significant a source of the chicken’s diet compared to arthropods, for juvenile chickens, or 

grain for adult chickens (Lehman, 1941). A biologically representative refinement to the 

screening assessment follows: 

Field metabolic rate kcal/day = 1.146(772)0.749 = 166.73 kcal/day 

(USEPA 1993, body weight reflects screening assumption for the Attwater’s greater 

prairie-chicken from US FWS Recovery Plan (USFWS, 2010); 

http://ecos.fws.gov/docs/recovery_plan/100426.pdf)

Mass of prey consumed per day = 166.73 kcal/day/(1.7 kcal/g ww X 0.72 AE) = 136.22 

g/day

(1.7 is energy content of prey item from USEPA (1993); 0.72 is assimilation efficiency 

from USEPA 1993, assumption of insect prey from USFWS, 2010, Lehman, 1941)

Mass of DCSA in insect diet 42.5 mg/kg-ww (conservative assumption of Kenaga 

nomogram relationship between arthropod residues and broadleaf plant tissue residues 

based on 61.1 mg/kg maximum value from empirical data for soybean forage)
13

Mass of DCSA in daily diet = 136.22 g/day X 42.5 mg DCSA/kg-ww insect prey X 0.001 

= 5.79 mg/day

Daily dose in chicken = 5.79 mg DCSA/day/0.772= 7.50 mg/kg-bw/day

Avian Chronic Endpoint of 695 mg/kg-diet (from mallard duck study for parent dicamba) 

modified by ratio of parent dicamba to metabolite DCSA from chronic rat studies (17x) 

results in Avian chronic NOAEC of 40.88 mg/kg-diet.

RQ for chronic exposure: RQ = 7.5/40.88 = 0.18

An RQ of 0.18 does not exceed the chronic LOC of 1.0; consequently a “no effect” 

determination is concluded for the Atwater’s greater prairie chicken.

Eskimo curlew

Dicamba Acute Effects Assessment

Initial screening level risk assessment results for birds indicated concerns for acute effects. The 

Eskimo curlew is a species determined to potentially occupy treated agricultural fields such as

cotton and soybean fields and thus be subject to exposure to dicamba DGA on the treated field. 

Historically, the species’ breeding grounds were in Alaska and the Northwest Territories, Canada 

and overwintered in South America (USFWS, 2011a). The curlew is thought to have crossed the 

Gulf of Mexico into Texas during their spring migrations and preferred burned and disturbed 

prairie habitats and agricultural fields where they fed primarily on grasshoppers and other insects

(Gill et al., 1998, USFWS, 2011a). The assumptions in the initial screen were adjusted to 

account for the Eskimo curlew’s biology. As a conservative approach, EPA used the modeled 

upper bound T-REX modeled residues for arthodpods to evaluate the potential risk posed by 

dicamba applications at this time. This is considered a conservative approach as 100% of the 

Eskimo curlew’s diet would be considered to consist of exposed arthropods receiving the upper 

bound Kenaga nomogram dicamba residues from the spray application. A biologically 

representative refinement to the screening assessment follows:

Field metabolic rate kcal/day = 1.146(240)

0.749 = 69.5 kcal/day 

(USEPA 1993, body weight reflects screening assumption for the Eskimo curlew from 

USGS, 2014 http://www.npwrc.usgs.gov/resource/birds/curlew/identif.htm)

Mass of prey consumed per day = 69.5 kcal/day/(1.7 kcal/g ww X 0.72 AE) = 56.8 g/day

(1.7 is energy content of prey item from USEPA (1993); 0.72 is assimilation efficiency 

from USEPA 1993, assumption of insect prey from USGS 2014)

Mass of dicamba DGA in insect diet 102.99 mg/kg-ww from T-REX run
14

Mass of dicamba DGA in daily diet = 56.8 g/day X 102.99 mg dicamba DGA/kg-ww 

insect prey X 0.001 = 5.85 mg/day

Daily dose in curlew= 5.85 mg dicamba DGA/day/0.24= 24.37 mg/kg-bw/day

Curlew LD50 mg/kg-bw = 188 mg/kg-bw X (240/178)(1.15-1) = 196.6 mg/kg-bw

The RQ for acute effects = 24.37/196.6 = 0.12

An acute RQ of 0.12 exceeds the acute LOC of 0.1. 

DCSA Assessment Eskimo curlew consuming arthropods that had previously consumed soybean 

forage

EFED considered DCSA residues in arthropods to be the maximum measured DCSA residues 

from broadleaf plants, modified by the Kenaga nomogram relationship between broadleaf plant 

and arthropods as a conservative pesticide load in the prey base. This is considered a 

conservative approach as the estimated residues in arthropods are higher than for the other likely 

dietary items and 100% of the curlew’s diet would be considered to consist of exposed 

arthropods feeding on dicamba-tolerant soybean plants that had the highest measured DCSA 

residues. A biologically representative refinement to the screening assessment follows: 

Field metabolic rate kcal/day = 1.146(240)

0.749 = 69.5 kcal/day 

(USEPA 1993, body weight reflects screening assumption for the Eskimo curlew from 

USGS, 2014 http://www.npwrc.usgs.gov/resource/birds/curlew/identif.htm)

Mass of prey consumed per day = 69.5 kcal/day/(1.7 kcal/g ww X 0.72 AE) = 56.8 g/day

(1.7 is energy content of prey item from USEPA (1993); 0.72 is assimilation efficiency 

from USEPA 1993, assumption of insect prey from USGS 2014)

Mass of DCSA in insect diet 42.5 mg/kg-ww (conservative assumption of Kenaga 

nomogram relationship between arthropod residues and broadleaf plant tissue residues 

based on 61.1 mg/kg maximum value from empirical data for soybean forage)

Mass of DCSA in daily diet = 56.8 g/day X 42.5 mg DCSA/kg-ww insect prey X 0.001 = 

2.41 mg/day

Daily dose in chicken = 2.41 mg DCSA/day/0.240 = 10.06 mg/kg-bw/day

Avian Chronic Endpoint of 695 mg/kg-diet (from mallard duck study for parent dicamba) 

modified by ratio of parent dicamba to metabolite DCSA from chronic rat studies (17x) 

results in Avian chronic NOAEC of 40.88 mg/kg-diet.
15

RQ for chronic exposure: RQ = 10.06/40.88 = 0.25

An RQ of 0.25 does not exceed the chronic LOC of 1.0

As the analysis above concluded that exposures to the curlew from dicamba had potential to be

above the acute level of concern, the assessment was further refined by using of the Terrestrial 

Investigation Model (TIM) to quantify the potential risks of dicamba DGA to the Eskimo curlew. 

The model was parameterized with two assumptions about the frequency of time they would 

spend on the field (frequency on field: FOF): 10 percent and 90 percent. These assumptions 

reflect the overall uncertainty of how much time in a given migration period the birds would 

encounter a feeding opportunity on crop land. The model simulated a three-day stopover in 

agricultural land during the early pre-emergence herbicide application season to simulate feeding 

during migration. The food uptake was raised to a 3X daily intake rate to simulate migratory 

gorging behavior. The results indicated a 5.4-94% chance of mortality to one or more Eskimo 

curlews (Table 4). The dominant route of exposure that contributes to mortality is through diet 

(Table 5). The input parameters used in this model run are included in Appendix 3. 

Table 4. Risk of dicamba exposure to individual Eskimo curlew.

Mean FOF (%) % Chance of mortality to one or more birds

10 5.4

90 94

Table 5. Relative contributions of exposure routes to lethal doses in simulated birds. Mean (and 

standard deviation) values provided.

Exposure route* 10% FOF 90% FOF

Food 93 (6.6) 84 (7.5)

Drinking water: Puddles 0 0

Drinking water: Dew 0 0

Dermal Contact 6.8 (6.6) 16 (7.5)

*Inhalation and direct spray routes of exposure were turned off.

Given the predicted chance of individual mortalities, it might be reasonable to expect effects if 

Eskimo curlews encountered treat fields. Known occurrences of the species span Galveston 

County in Texas and 23 counties in Nebraska: Nuckolls, Jefferson, Saline, Polk, Wayne, Pierce, 

Platte, Boone, Madison, Antelope, Merrick, Stanton, Fillmore, York, Seward, Clay, Cedar, 

Thayer, Hamilton, Nance, Knox, Colfax, and Butler. See Appendix 4 for range and land cover 

analysis.

However, the species by all accounts is extremely rare. The U.S. Fish and Wildlife Service 

summarized curlew numbers in a recent Biological Opinion (USFWS 2012a) for the rodenticide 

chlorophacinone:
16

Recent quantitative methods used to evaluate the probability of the Eskimo curlew’s 

existence have estimated extinction dates of 1967 and 1965, respectively, with the 

upper bounds of 95 percent confidence intervals in 1977 and 1970 (Elphick et al. 

2010, FWS 2011e). These estimates are based on the last uncontroversial record of 

observance, a specimen that was shot in Barbados in 1963 (FWS 2011e). From 1963 

to the spring of 2009, 39 potential sightings have occurred in 22 different years 

(Committee on the Status of Endangered Wildlife in Canada 2009); however, the 

reliability of these sightings is variable, and none have been confirmed by physical 

evidence (FWS 2011e). If controversial records of observance are included, then the 

analysis estimates an extinction date of 2008 with the upper bound of 95 percent 

confidence interval reaching 2013 (FWS 2011e).

In the case of chlorophacinone, EPA had initially made a “likely to adversely affect” 

determination for the curlew based on direct acute effects. This pesticide application involved 

potential large geographic areas of rangeland habitat, likely more favorable to curlews than 

maintained agricultural fields. The conclusion of the Biological Opinion was:

Eskimo curlews are likely already extinct or at best extremely rare; thus, direct and 

indirect effects from Rozol exposure are so highly unlikely to occur as to be considered 

discountable. Therefore, the Service does not anticipate adverse effects to Eskimo 

curlew from use of Rozol on BTPDs. No critical habitat for the Eskimo curlew has been 

designated; therefore none will be affected.

It is reasonable to reach a similar conclusion with dicamba DGA, a compound of likely lower 

acute toxic hazard than chlorophacinone and proposed for use on land cover more marginal for 

curlews than the chlorophacinone case. Therefore the Agency determines that the proposed 

labeled use of dicamba DGA is “not likely to adversely affect” (NLAA) the Eskimo curlew 

because exposures are so highly unlikely to occur as to be considered discountable. 

EPA informally consulted with the U.S. Fish and Wildlife Service on the NLAA effects 

determination made for the Eskimo Curlew. The concurrence memo is appended in 

Appendix 6. 

Herpifauna

Using birds as a surrogate for reptiles and terrestrial-phase amphibians, consistent with the 

Overview document (USEPA, 2004), the screening level assessment suggests that reptiles and 

terrestrial-phase amphibians could be at risk of effects from acute exposures to dicamba DGA or 

chronic exposures to DCSA on treated fields. Of the reptile and amphibian species identified as 
17

potentially at acute risk in the seven states, one reptile and one amphibian are reasonably 

expected to occur on treated soybean and cotton fields. Therefore, species specific biological 

information and dicamba DGA use patterns were considered in more depth to further refine the 

assessment and effects determinations for those species. 

Eastern Indigo snake

Dicamba Acute Effects Assessment

Initial screening level risk assessment results for birds/reptiles indicated concerns for acute 

effects to reptiles (using birds as a surrogate). The Eastern Indigo Snake is known or believed to 

occur in Alabama, Florida and Georgia (USFWS Species Profile Page, 

http://ecos.fws.gov/tess_public/profile/speciesProfile.action?spcode=C026). In Georgia, the 

species has been observed moving from sandhill habitat to the vicinity of agricultural fields in 

summer (Speake et al., 1978). Therefore, the species was determined to potentially occupy 

treated cotton and soybean fields and thus be subject to exposure to dicamba DGA on the treated 

field. The indigo snake feeds largely on other snakes, small tortoises, small mammals, and 

amphibians (USFWS, 1983). Using the conservative assumptions that the prey species is 

represented by a 35g mammal that feeds exclusively on contaminated short grass receiving the 

upper bound Kenaga resiudes from the spray application of dicamba and that the snake 

exclusively feeds on this prey species, the assumptions in the initial screen were adjusted to 

account for the indigo snake’s biology: 

Field metabolic rate kcal/day = 0.0530(4300)

0.799 = 42.4 kcal/day 

(USEPA 1993, body weight reflects screening assumption for the indigo snake from 

Biological Information on Listed Species of Amphibians and Model Parameterization for 

Pesticide Effects Determinations, United States Environmental Protection Agency, 

Office of Pesticide Programs July 15, 2013)

Mass of prey consumed per day = 42.4 kcal/day/(1.7 kcal/g ww X 0.78 AE) = 32 g/day

(1.7 is energy content of prey item from USEPA (1993); 0.78 is assimilation efficiency 

from USEPA 1993, assumption of small mammal prey from the recovery plan (USFWS, 

1983) and Biological Information on Listed Species of Amphibians and Model 

Parameterization for Pesticide Effects Determinations, United States Environmental 

Protection Agency, Office of Pesticide Programs July 15, 2013).

Mass of dicamba DGA in a 35-g mammal diet 173.26 mg/kg-ww from T-REX run

Mass of dicamba DGA in daily diet = 32 g/day X 173.26 mg dicamba DGA/kg-ww 

mammal prey X 0.001 = 5.54 mg/day

Daily dose in snake= 5.54 mg dicamba DGA/day/4.3= 1.29 mg/kg-bw/day
18

Appropriate scaling factors are not available for reptiles and amphibians so the acute 

toxicity value for the bobwhite quail (most sensitive avian species for which acute data 

are available) serves as a surrogate (USEPA, 2004) toxicity value for the tortoise:

Snake LD50 mg/kg-bw = 188 mg/kg-bw

The RQ for acute effects = 1.29/188 = 0.007

An acute RQ of 0.007 does not exceed the acute listed species LOC of 0.1. Consequently, EPA 

makes a “no effect” determination for the indigo snake.

DCSA Assessment for Eastern indigo snake consuming prey that had previously consumed 

soybean forage

The indigo snake feeds largely on other snakes, small tortoises, small mammals, and amphibians 

(USFWS, 1983). Using the conservative assumptions that the prey species is represented by a

mammal that feeds exclusively on exposed soybean plant tissue containing the maximum 

measured DCSA residues of 61.1 ppm and that the snake exclusively feeds on this prey species, 

the assumptions in the initial screen were adjusted to account for the indigo snake’s biology:

Field metabolic rate kcal/day = 0.0530(4300)0.799 = 42.4 kcal/day 

(USEPA 1993, body weight reflects screening assumption for the indigo snake from 

Biological Information on Listed Species of Amphibians and Model Parameterization for 

Pesticide Effects Determinations, United States Environmental Protection Agency, 

Office of Pesticide Programs July 15, 2013)

Mass of prey consumed per day = 42.4 kcal/day/(1.7 kcal/g ww X 0.78 AE) = 32 g/day

(1.7 is energy content of prey item from USEPA (1993); 0.78 is assimilation efficiency 

from USEPA 1993, assumption of small mammal prey from the recovery plan (USFWS, 

1983) and Biological Information on Listed Species of Amphibians and Model 

Parameterization for Pesticide Effects Determinations, United States Environmental 

Protection Agency, Office of Pesticide Programs July 15, 2013).

Mass of DCSA in a mammal diet 61.1 mg/kg-ww (maximum empirical residue data on 

soybean forage)

Mass of DCSA in snake’s daily diet = 32 g/day X 61.1 mg dicamba DGA/kg-ww

mammal prey X 0.001 = 1.96 mg DCSA/day

Daily dose in snake= 1.96 mg DCSA/day/4.3= 0.46 mg/kg-bw/day
19

Avian Chronic Endpoint of 695 mg/kg-diet (from mallard duck (surrogate species for 

reptiles) study for parent dicamba) modified by ratio of parent dicamba to metabolite 

DCSA from chronic rat studies (17x) results in Avian chronic NOAEC of 40.88 mg/kgdiet.

RQ for chronic exposure: RQ = 0.46/40.88 = 0.01

An RQ of 0.01 does not exceed the chronic LOC of 1.0; consequently a “no effect” 

determination is concluded for the Eastern indigo snake.

Houston toad

Initial screening level risk assessment results for birds/terrestrial-phase amphibians indicated 

concerns for acute effects to amphibians (using birds as a surrogate). Historically, Houston toads 

ranged across the central coastal region of Texas in grassland/prairie ecosystems or in or near 

forested habitat and metamorphosed adult toads likely eat small terrestrial arthropods (USFWS, 

2011b). As a conservative approach, EPA used the modeled upper bound T-REX residues for 

arthodpods to evaluate the potential risk posed by dicamba applications at this time. This is 

considered a conservative approach as 100% of the toad’s diet would be considered to consist of 

exposed arthropods receiving the upper bound Kenaga nomogram dicamba residues from the 

spray application. A biologically representative refinement to the screening assessment follows:

Field metabolic rate kcal/day = 0.0530(45)

0.799 = 1.1 kcal/day 

(USEPA 1993, body weight reflects screening assumption for the Houston toad from 

Biological Information on Listed Species of Amphibians and Model Parameterization for 

Pesticide Effects Determinations, United States Environmental Protection Agency, 

Office of Pesticide Programs July 15, 2013)

Mass of prey consumed per day = 1.1 kcal/day/(1.7 kcal/g ww X 0.72 AE)= 0.9 g/day

(1.7 is energy content of prey item from USEPA (1993); 0.72 is assimilation efficiency 

from USEPA 1993, insect diet assumption from USFWS, 2011b and Biological 

Information on Listed Species of Amphibians and Model Parameterization for Pesticide 

Effects Determinations, United States Environmental Protection Agency, Office of 

Pesticide Programs July 15, 2013)

Mass of dicamba DGA in insect diet 102.99 mg/kg-ww from T-REX run

Mass of dicamba DGA in daily diet = 0.9 g/day X 102.99 mg dicamba DGA/kg-ww 

insect prey X 0.001 = 0.09 mg/day

Daily dose in toad= 0.09 mg dicamba DGA/day/0.045= 2.06 mg/kg-bw/day
20

Toad LD50 mg/kg-bw = 188 mg/kg-bw X (45/178)(1.15-1) = 152.96 mg/kg-bw

(assumes the same scaling as for birds)

The RQ for acute effects = 2.06/152.96 = 0.01

An acute RQ of 0.01 does not exceed the acute listed species LOC of 0.1. Consequently, EPA 

makes a “no effect” determination for the Houston toad.

DCSA Assessment for Houston toad consuming prey that had previously consumed soybean 

forage

EFED considered DCSA residues in arthropods to be the maximum measured DCSA residues 

from broadleaf plants, modified by the Kenaga nomogram relationship between broadleaf plant 

and arthropods as a conservative pesticide load in the prey base. This is considered a 

conservative approach as 100% of the toad’s diet would be considered to consist of exposed 

arthropods feeding on dicamba-tolerant soybean plants that had the highest measured DCSA 

residues. A biologically representative refinement to the screening assessment follows: 

Field metabolic rate kcal/day = 0.0530(45)0.799 = 1.1 kcal/day 

(USEPA 1993, body weight reflects screening assumption for the Houston toad from 

Biological Information on Listed Species of Amphibians and Model Parameterization for 

Pesticide Effects Determinations, United States Environmental Protection Agency, 

Office of Pesticide Programs July 15, 2013)

Mass of prey consumed per day = 1.1 kcal/day/(1.7 kcal/g ww X 0.72 AE)= 0.9 g/day

(1.7 is energy content of prey item from USEPA (1993); 0.72 is assimilation efficiency 

from USEPA 1993, insect diet assumption from USFWS, 2011b and Biological 

Information on Listed Species of Amphibians and Model Parameterization for Pesticide 

Effects Determinations, United States Environmental Protection Agency, Office of 

Pesticide Programs July 15, 2013)

Mass of DCSA in insect diet 42.5 mg/kg-ww (conservative assumption of Kenaga 

nomogram relationship between arthropod residues and broadleaf plant tissue residues 

based on 61.1 mg/kg maximum value from empirical data for soybean forage)

Mass of DCSA in daily diet = 0.9 g/day X 42.5 mg dicamba DGA/kg-ww insect prey X 

0.001 = 0.038 mg/day

Daily dose in toad= 0.038 mg DCSA/day/0.045= 0.85 mg/kg-bw/day

Avian Chronic Endpoint of 695 mg/kg-diet (from mallard duck (surrogate species for 

terrestrial-phase amphibians) study for parent dicamba) modified by ratio of parent 
21

dicamba to metabolite DCSA from chronic rat studies (17x) results in Avian chronic 

NOAEC of 40.88 mg/kg-diet.

RQ for chronic exposure: RQ = 0.85/40.88 = 0.02

An RQ of 0.02 does not exceed the chronic LOC of 1.0; consequently a “no effect” 

determination is concluded for the Houston toad.

Mammals

The screening-level assessments indicated that acute risk to mammals was not expected as no 

acute RQs exceeded the Agency’s LOC (0.1) for acute risk (USEPA 2011. D378444, p. 15). 

However, the soybean screening-level assessment (USEPA, 2011) indicated that mammals could 

be at reproductive risk from chronic exposures to dicamba DGA on treated fields, though the 

cotton screening level and concurrently issued soybean addendum (USEPA, 2016a and USEPA, 

2016b) indicated that chronic exposures to dicamba DGA would be below the chronic LOC 

(1.0). This difference is due to soybean screening level risk assessment’s use of a chronic 

endpoint from the rat 2-generation study (MRID 43137101), of 45 mg/kg-bw for the NOAEL, 

based on decreased pup weight at 136 mg/kg-bw compared to the concurrent controls. HED 

recently reanalyzed the data from this study (USEPA, 2016c; D431873) in comparison to the 

historical control database range and determined that the NOAEL and LOAEL should be raised 

to 136 and 450 mg/kg-bw, respectively, as pup weights in each generation in the 136 mg/kg-bw 

treatment group were within the historical control range and above the historical control mean 

for the F1, F2A and F2B generations. Therefore, the cotton screening level risk assessment, the 

concurrently issued soybean addendum and this refined endangered species risk assessment use 

this revised NOAEL for dicamba DGA salt. 

The concurrently issued soybean addendum did indicate that chronic exposures to dicamba’s 

metabolite, DCSA, residues in soybean could be a concern, while the screening level cotton 

assessment indicated that chronic exposures to DCSA residues in cotton would not exceed the 

Agency’s LOC for chronic risk. Therefore, EPA only conducted a refined assessment for 

chronic exposures to DCSA in soybeans for listed species that could reasonably be expected to 

occur on treated soybean fields. 

Of the mammalian species identified as potentially at risk in the seven states, four are reasonably 

expected to occur on treated soybean fields. Species specific biological information and dicamba 

DGA use patterns were considered in more depth to further refine the assessment and effects 

determinations for the four species potentially expected to occur on treated soybean fields. 

Virginia big-eared bat 
22

Dicamba Effects Assessment

Initial screening level risk assessment results for mammals identified concerns for chronic effects

to mammals. This bat is assumed to potentially forage over treated fields and thus be subject to 

exposure to dicamba DGA on the treated field. Big-eared bats feed principally on small moths 

and other insects (USFWS, 1984). Exposure assumptions from the screening assessment were 

refined to account for the Virginia big-eared bat’s biology and contained the conservative 

assumption that bats would feed exclusively on exposed insects/arthropods having received the 

upper bound Kenaga residues from the spray application of dicamba.

Field metabolic rate kcal/day = 0.6167(7g)

0.862 = 3.3 kcal/day 

(USEPA 1993, body weight 7 g reflects screening assumption for the bat USFWS 2014a; 

http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=A080)

Mass of prey consumed per day = (3.3 kcal/day)/(1.7 kcal/g ww X 0.87 AE) = 2.2 g/day 

(1.7 is energy content of prey item from USEPA (1993); 0.87 is assimilation efficiency 

from USEPA 1993)

Mass of dicamba DGA in insect diet = 102.99 mg/kg-ww from T-REX run

Mass of dicamba DGA in daily diet = 2.2 g/day X 102.99 mg dicamba DGA/kg-ww 

mammal prey X 0.001 = 0.23 mg/day

Daily dose in bat = 0.23 mg dicamba DGA/day/0.007 kg = 32.37 mg/kg-bw/day

Bat NOAEL mg/kg-bw/day = 136 mg/kg-bw X (350/7)

0.25 = 361.64 mg/kg-bw

RQ for chronic exposure = RQ =32.37/361.64= 0.09

A chronic RQ of 0.09 does not exceed the chronic LOC of 1.0. Consequently, EPA makes a 

“no effect” determination for the the Virginia big-eared bat.

DCSA Assessment for Virginia big-eared bat consuming prey that had previously consumed 

soybean forage

Initial screening level risk assessment results for the Virginia big-eared bat were refined to 

account for the bat’s biology and contained the conservative assumption that bats would feed 

exclusively on exposed insects/arthropods feeding on dicamba-tolerant soybean plant tissues that 

had the highest measured DCSA residues.

Field metabolic rate kcal/day = 0.6167(7g)0.862 = 3.3 kcal/day 
23

(USEPA 1993, body weight 7 g reflects screening assumption for the bat USFWS 2014a; 

http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=A080)

Mass of prey consumed per day = (3.3 kcal/day)/(1.7 kcal/g ww X 0.87 AE) = 2.2 g/day 

(1.7 is energy content of prey item from USEPA (1993); 0.87 is assimilation efficiency 

from USEPA 1993)

Mass of DCSA in insect diet = 42.5 mg/kg-ww (conservative assumption of Kenaga 

nomogram relationship between arthropod residues and broadleaf plant tissue residues 

based on 61.1 mg/kg maximum value from empirical data for soybean forage)

Mass of DCSA in daily diet = 2.2 g/day X 42.5 mg DCSA/kg-ww mammal prey X 0.001 

= 0.094 mg/day

Daily dose in bat = 0.094 mg DCSA/day/0.007 kg = 13.357 mg/kg-bw/day

Bat NOAEL mg/kg-bw/day = 8 mg/kg-bw X (350/7)0.25 = 21.27 mg/kg-bw

RQ for chronic exposure = RQ =13.357/21.27 = 0.63

A chronic RQ of 0.63 does not exceed the chronic LOC of 1.0; consequently a “no effect” 

determination is concluded for the Virginia big-eared bat.

Ocelot

Dicamba Acute Effects Assessment

Initial screening level risk assessment results for mammals identified concerns for chronic effects

to mammals. The recovery plan for the ocelot (USFWS, 1990, revised 2010) describes the 

ocelot’s habitat in Texas as dense thornscrub communities on Laguna Atascosa National Wildlife 

Refuge and on private lands in three Texas counties. The ocelot requires dense vegetation 

(>75% canopy cover), with 95% cover of the shrub layer preferred in Texas and it feeds 

primarlily on rabbits, rodents, birds and lizards (USFWS, 1990). Although this indicates the 

ocelot is unlikely to inhabit agricultural row crop areas, the prey species it feeds on could be 

exposed in soybean or cotton fields and then subsequently consumed by the ocelot away from 

the field. Using the assumption that the prey species is represented by a 1000 g mammal 

(conservative as to rabbits) and using the conservative assumptions that the prey feeds 

exclusively on exposed short grass receiving the upper bound Kenaga residues from the spray 

application of dicamba, exposure assumptions from the screening assessment were adjusted to 

account for ocelot’s biology: 

Field metabolic rate kcal/day = 0.6167(16000)0.862 = 2594 kcal/day 
24

(USEPA 1993, body weight reflects screening assumption for the ocelot from Recovery 

Plan (USFWS 1990; http://ecos.fws.gov/docs/recovery_plan/100826.pdf ))

Mass of prey consumed per day = 2594 kcal/day /(1.7 kcal/g ww X 0.84 AE)= 1816 

g/day

(1.7 is energy content of prey item from USEPA (1993); 0.84 is assimilation efficiency 

from USEPA 1993, mammal diet assumption from Recovery Plan (USFWS 1990;

http://ecos.fws.gov/docs/recovery_plan/100826.pdf ))

Mass of dicamba DGA in 1kg mammal diet 40.17 mg/kg-ww from T-REX run

Mass of dicamba DGA in daily diet = 1816 g/day X 40.17 mg dicamba DGA/kg-ww 

mammal prey X 0.001 = 72.95 mg/day

Daily dose in ocelot = 72.95 mg dicamba DGA/day/16= 4.56 mg/kg-bw/day

Ocelot NOAEL mg/kg-bw/day = 136 mg/kg-bw (350/16000)(0.25) = 52.30 mg/kg-bw

The RQ for chronic effects = 4.56/52.30 = 0.09 

A chronic RQ of 0.09 does not exceed the chronic LOC of 1.0. Even if the ocelot were assumed 

to consume a smaller (35-g mammal) prey species that had consumed exposed short grass (TREX modeled residues of 173.26 mg/kg-ww), the chronic RQ (0.38) would still be below the 

LOC. Consequently, EPA makes a “no effect” determination for the ocelot.

DCSA Assessment for Ocelot consuming prey that had previously consumed exposed soybean forage

The first step in the refinement process is to calculate DCSA residues in the prey species. 

Using the assumption that the prey species is represented by a 1000 g mammal and the 

conservative assumptions that the prey animal feeds exclusively on exposed soybean 

forage containing the maximum measured residues of 61.1 ppm, EFED calculated the 

residues based on the following allometric equations (USEPA, 1993): 

1000 g mammal prey ingestion rate (dry) = 0.621(1000)0.564 =30.56 g /day

1000 g mammal prey ingestion rate (wet) = 30.56/0.2 = 152.8 g/day

DCSA residue in prey eating soybean forage/hay 61.1 mg DCSA/kg-food (ww) x 0.1528 

kg food/kg-bw = 9.34 mg/kg-bw/day
25

The next step is to determine the expected daily dose for a typical 16 kg ocelot, the 

adjusted NOAEL value and the chronic dose-based RQ for the ocelot based on the 

following allometric equations:

Field metabolic rate kcal/day = 0.6167(16000)0.862 = 2594 kcal/day 

(USEPA 1993, body weight reflects screening assumption for the ocelot from Recovery 

Plan (USFWS 1990; http://ecos.fws.gov/docs/recovery_plan/100826.pdf ))

Mass of prey consumed per day = 2594 kcal/day /(1.7 kcal/g ww X 0.84 AE)= 1816 

g/day

(1.7 is energy content of prey item from USEPA (1993); 0.84 is assimilation efficiency 

from USEPA 1993, mammal diet assumption from Recovery Plan (USFWS 1990;

http://ecos.fws.gov/docs/recovery_plan/100826.pdf ))

Mass of DCSA in 1kg mammal diet 9.34 mg/kg-ww (based on allometric equations 

above and maximum empirical residue data on soybean forage)

Mass of DCSA in daily diet = 1816 g/day X 9.34 mg DCSA/kg-ww mammal prey X 

0.001 = 16.96 mg/day

Daily dose in ocelot = 16.96 mg DCSA/day/16= 1.060 mg/kg-bw/day

Ocelot NOAEL mg/kg-bw/day = 8 mg/kg-bw (350/16000)(0.25) = 3.08 mg/kg-bw

The RQ for chronic effects = 1.06/3.08 = 0.35

A chronic RQ of 0.35 does not exceed the chronic LOC of 1.0. Consequently, EPA makes a 

“No Effect” determination for the ocelot.

Gulf Coast jaguarundi

Initial screening level risk assessment results for mammals identified concerns for chronic 

effects. The recovery plan for the jaguarundi (USFWS, 2012b) describes the species as using 

desne thorny shrublands or woodlands and bunchgrass pastures adjacent to dense brush or 

woody cover and preying mainly on birds, small mammals, and reptiles. Although this indicates 

the jaguarundi is unlikely to inhabit agricultural row crop areas, the prey species it feeds on 

could be exposed in soybean or cotton fields and then subsequently consumed by the juaguarundi

away from the field. Using the assumptions that the prey species is represented by a 1000 g 

mammal and using the conservative assumptions that the prey feeds exclusively on exposed

short grass receiving the upper bound Kenaga residues from the spray application of dicamba, 
26

exposure assumptions from the screening assessment were adjusted to account for the 

jaguarundi’s biology: 

Field metabolic rate kcal/day = 0.6167(90000)0.862= 11498 kcal/day 

(USEPA 1993, body weight reflects screening assumption for the jaguarondi from 

Recovery Plan, USFWS 2012b) 

(http://www.fws.gov/southwest/es/Documents/R2ES/Gulf_Coast_Jaguarundi_DRAFT_R

ecovery_Plan_24Dec2012.pdf))

Mass of prey consumed per day = 11498 kcal/day/(1.7 kcal/g ww X 0.84 AE)= 8051

g/day

(1.7 is energy content of prey item from USEPA (1993); 0.84 is assimilation efficiency 

from USEPA 1993, 1 kg mammal diet from Recovery Plan, USFWS 2012b) 

(http://www.fws.gov/southwest/es/Documents/R2ES/Gulf_Coast_Jaguarundi_DRAFT_R

ecovery_Plan_24Dec2012.pdf))

Mass of dicamba DGA in 1 kg mammal diet 40.17 mg/kg-ww from T-REX run

Mass of dicamba DGA in daily diet = 8051 g/day X 40.17 mg dicamba DGA/kg-ww 

mammal prey X 0.001 = 323 mg/day

Daily dose in jaguarundi = 323 mg dicamba DGA/day/90= 3.59 mg/kg-bw/day

Jaguarundi NOAEL mg/kg-bw/day = 136 mg/kg-bw X (350/90000)

(0.25) = 33.96mg/kgbw

The RQ for chronic effects = 3.59/33.96 = 0.11. 

A chronic RQ of 0.11 does not exceed the chronic LOC of 1.0. Even if the jaguarundi were 

assumed to consume a smaller (35-g mammal) prey species that had consumed exposed short 

grass (T-REX modeled residues of 173.26 mg/kg-ww), the chronic RQ (0.46) would still be 

below the LOC. Consequently, EPA makes a “no effect” determination for the jaguarundi.

DCSA Assessment for Jaguarundi consuming prey that had previously consumed soybean forage

The first step in the refinement process is to calculate DCSA residues in the prey species. 

Using the conservative assumptions that the prey species is represented by a 1000 g 

mammal that feeds exclusively on exposed soybean forage containing the maximum 

measured residues of 61.1 ppm, EFED calculated the residues based on the following 

allometric equations (USEPA, 1993): 

1000 g mammal prey ingestion rate (dry) = 0.621(1000)0.564 =30.56 g /day
27

1000 g mammal prey ingestion rate (wet) = 30.56/0.2 = 152.8 g/day

DCSA residue in prey eating soybean forage/hay 61.1 mg DCSA/kg-food (ww) x 0.1528 

kg food/kg-bw = 9.34 mg/kg-bw/day

The next step is to determine the expected daily dose for a typical 90 kg jaguarundi, the 

adjusted NOAEL value and the chronic dose-based RQ for the ocelot based on the 

following allometric equations:

Field metabolic rate kcal/day = 0.6167(90000)0.862= 11498 kcal/day 

(USEPA 1993, body weight reflects screening assumption for the jaguarondi from 

Recovery Plan, USFWS 2012b) 

(http://www.fws.gov/southwest/es/Documents/R2ES/Gulf_Coast_Jaguarundi_DRAFT_R

ecovery_Plan_24Dec2012.pdf))

Mass of prey consumed per day = 11498 kcal/day/(1.7 kcal/g ww X 0.84 AE)= 8051

g/day

(1.7 is energy content of prey item from USEPA (1993); 0.84 is assimilation efficiency 

from USEPA 1993, 1 kg mammal diet from Recovery Plan, USFWS 2012b) 

(http://www.fws.gov/southwest/es/Documents/R2ES/Gulf_Coast_Jaguarundi_DRAFT_R

ecovery_Plan_24Dec2012.pdf))

Mass of DCSA in 1 kg mammal diet 9.34 mg/kg-ww (based on allometric equations 

above and maximum empirical DCSA residues on soybean forage)

Mass of DCSA in daily diet = 8051 g/day X 9.34 mg DCSA/kg-ww mammal prey X 

0.001 = 75.20 mg/day

Daily dose in jaguarundi = 75.20 mg DCSA/day/90= 0.84 mg/kg-bw/day

Jaguarundi NOAEL mg/kg-bw/day = 4 mg/kg-bw X (350/90000)(0.25) = 2.00 mg/kg-bw

The RQ for chronic effects = 0.84/2.00 = 0.42. 

A chronic RQ of 0.42 does not exceed the chronic LOC of 1.0. Consequently, EPA makes a 

“no effect” determination for the jaguarundi.

Red wolf

Initial screening level risk assessment results for mammals identified concerns for chronic 

effects. Since 1987, reintroduced red wolves have been identified in a variety of habitats 

including wetlands, pine forests, upland shrubs, and cropland (USFWS, 2007). The diet of red 
28

wolves is primarily white-tailed deer, but they may also eat smaller mammals such as raccoons, 

rabbits and mice (Whitaker and Hamilton, 1998). Using the conservative assumptions that the 

prey species is represented by a 1000 g mammal (conservative for deer, raccoons and rabbits) 

that feeds exclusively on exposed short grass receiving the upper bound Kenaga residues from 

the spray application of dicamba, exposure assumptions from the screening assessment were 

adjusted to account for the red wolf’s biology, specifically their consumption of other mammals 

that may have been exposed to dicamba DGA residues in cotton and soybean fields.

Field metabolic rate kcal/day = 0.6167(36000)0.862= 5219 kcal/day (USEPA 1993, body 

weight reflects screening assumption for the red wolf from Whitaker and Hamilton 

(1998))

Mass of prey consumed per day = 5219 kcal/day/(1.7 kcal/g ww X 0.84 AE)= 3654 g/day

(1.7 is energy content of prey item from USEPA (1993); 0.84 is assimilation efficiency 

from USEPA 1993, 1 kg mammal diet from Whitaker and Hamilton (1998))

Mass of dicamba DGA in 1 kg mammal diet 40.17 mg/kg-ww from T-REX run

Mass of dicamba DGA in daily diet = 3654 g/day X 40.17 mg dicamba DGA/kg-ww 

mammal prey X 0.001 = 147 mg/day

Daily dose in wolf = 147 mg dicamba DGA/day/36= 4.08 mg/kg-bw/day

Wolf NOAEL mg/kg-bw/day = 136 mg/kg-bw X (350/36000)

(0.25) = 42.71 mg/kg-bw

The RQ for chronic effects = 4.08/42.71 = 0.10. 

A chronic RQ of 0.10 does not exceed the chronic LOC of 1.0. Consequently, EPA makes a 

“no effect” determination for the red wolf.

DCSA Assessment for red wolf consuming prey that had previously consumed soybean forage

The first step in the refinement process is to calculate DCSA residues in the prey species. 

Using the assumption that the prey species is represented by a 1000 g mammal and the 

conservative assumptions that the prey animal feeds exclusively on exposed soybean 

forage containing the maximum measured residues of 61.1 ppm, EFED calculated the 

residues based on the following allometric equations (USEPA, 1993): 

1000 g mammal prey ingestion rate (dry) = 0.621(1000)0.564 =30.56 g /day

1000 g mammal prey ingestion rate (wet) = 30.56/0.2 = 152.8 g/day
29

DCSA residue in prey eating soybean forage/hay 61.1 mg DCSA/kg-food (ww) x 0.1528 

kg food/kg-bw = 9.34 mg/kg-bw/day

The next step is to determine the expected daily dose for a typical 36 kg wolf, the 

adjusted NOAEL value and the chronic dose-based RQ for the wolf based on the 

following allometric equations:

Field metabolic rate kcal/day = 0.6167(36000)0.862= 5219 kcal/day (USEPA 1993, body 

weight reflects screening assumption for the red wolf from Whitaker and Hamilton 

(1998))

Mass of prey consumed per day = 5219 kcal/day/(1.7 kcal/g ww X 0.84 AE)= 3654 g/day

(1.7 is energy content of prey item from USEPA (1993); 0.84 is assimilation efficiency 

from USEPA 1993, 1 kg mammal diet from Whitaker and Hamilton (1998))

Mass of DCSA in 1 kg mammal diet 9.34 mg/kg-ww from allometric equations above 

and maximum empirical residue data.

Mass of DCSA in daily diet = 3654 g/day X 9.34 mg DCSA/kg-ww mammal prey X 

0.001 = 34.13 mg/day

Daily dose in wolf = 34.13 mg dicamba DGA/day/36= 0.95 mg/kg-bw/day

Wolf NOAEL mg/kg-bw/day = 8 mg/kg-bw X (350/36000)(0.25) = 2.51 mg/kg-bw

The RQ for chronic effects = 0.95/2.51 = 0.38 

A chronic RQ of 0.38 does not exceed the chronic LOC of 1.0. Consequently, EPA makes a 

“no effect” determination for the red wolf.

Critical Habitat Determinations

In addition to the species-specific effects determinations, EFED also conducted a critical habitat 

modification analysis consistent with the Overview Document as discussed earlier in this refined 

assessment. The critical habitat modification analysis is based on an assessment of how dicamba 

DGA salt would affect the U.S. Fish and Wildlife Service or National Marine Fisheries Service 

(the Services) established principle constituent elements (PCE’s) of the designated habitat as 

well as how direct species effects outcomes would impact critical habitat’s present and future 

utility for promoting the conservation of a particular listed species. The Agency will conclude 

‘modification’ of designated critical habitat if the range of designated critical habitat co-occurs 

with the states subject to the Federal action and one or more of the following conditions exist:
30

1. The available Services’ information indicates that cotton or soybean fields are habitat for 

the species and there is a “may affect” determination for the species associated with exposure to 

dicamba DGA salt or its degradate, DCSA, as labeled.

2. The available Services’ information indicates that the species uses cotton or soybean 

fields and one or more effects on taxonomic groups predicted for dicamba DGA salt or its 

degradate DCSA, on cotton and soybean fields would modify one or more of the designated 

PCEs.

If neither of the above conditions are met, EPA concludes “no modification.”

Results of Analysis

Of the 307 listed species within the states, there are 292 species identified in the effects 

determinations as not using cotton or soybean fields and 14 species using these fields (Appendix 

5). Critical habitats have been designated for 118 of the 307 species. One-hundred thirteen

(113) species with critical habitat were judged to not use cotton or soybean fields and so the 

critical habitat determination for these was “no modification.”

The remaining 5 species with critical habitat designations were assumed to use cotton or soybean 

fields and so the previous listed species effects determinations were consulted to ascertain if any 

were determined to be at risk for direct adverse effects. None of the species were determined to 

be at risk for direct adverse effects, so the PCE’s listed in the Services’ critical habitat 

designations were consulted to determine if, in light of the screening assessment risk findings, 

they would be impacted by on-field exposure to dicamba DGA salt. For all but one of these 

species, the PCE’s are not relatable to agricultural fields and so a determination of no 

modification has been made for these 4 species. 

The only remaining species using cotton or soybean fields and with critical habitat PCE’s 

relatable to agricultural fields was the whooping crane, for which agricultural fields were 

discussed as providing waste grain as a potential food source for migratory cranes. The only 

way the proposed dicamba DGA salt could affect this PCE is by making grain potentially toxic 

to the birds. As there is unlikely to be any edible waste grain remaining following cotton 

harvesting, it is unlikely that the proposed dicamba DGA salt use on cotton could affect this 

PCE, however the proposed use on soybean could affect this PCE by making waste soybean 

grain potentially toxic.

The Health Effects Division summarized available soybean grain residues of dicamba in the 

Human Health Risk Assessment for the Registration Eligibility Decision for Dicamba and 

Associated Salts (DP317703). Based on the soybean trials results, maximum residues of dicamba 

were 0.04 ppm in hay, 0.097 ppm in forage, and 8.13 ppm in seed 6-8 days post treatment 

(MRIDs 43814101 and 44089307). These measured values were used to set the tolerance value 

of 10 ppm for soybean seeds. The measured residues are not reasonably expected to be at a level 
31

raising a concern for direct effects to the whooping crane because the direct effects assessment 

for this species (presented in the Section 3 Risk Assessment Refined Endangered Species 

Assessment that assessed risks to endangered species in 16 states (Arkansas, Kansas, Louisiana, 

Illinois, Indiana, Iowa, Minnesota, Mississippi, Missouri, Nebraska, North Dakota, Ohio, 

Oklahoma, South Dakota, Tennessee, and Wisconsin {DP 416416, 420160, 420159, 420352, 

421434, 421723}) did not establish a concern for residues in other dietary items at much higher

(~ 1 order of magnitude) concentrations than would occur at the maximum measured residues in 

seed or if residues were present even at the tolerance level of 10.0 ppm. Because this analysis 

shows no direct effects of dicamba at levels that would be expected in the fields as waste grain, 

an indirect effect, there is no modification of critical habitat. Similarly, measured DCSA residues 

in waste soybean grain (0.44 ppm) would be well below the estimated DCSA concentrations in 

arthropods (42.5 ppm) used in the direct effects assessment for this species (D416516+, pp. 9-

10). Therefore, whooping crane critical habitat within the 7 states covered in this assessment

would not be modified.

Summary of Determinations for Critical Habitat

The Agency has determined that the proposed labeled use of dicamba DGA salt on cotton and 

soybeans will not modify designated critical habitat for all 118 species for which such habitats 

have been designated in AL, GA, KY, MI, NC, SC, and TX.

A summary of listed species identified as not being on agricultural fields with and without 

critical habitat designations for the seven states assessed for dicamba DGA salt is provided in 

Appendix 5.

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DC. March 24, 2016.

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Soybean and Cotton. DP Barcodes: 416416, 420160, 420159, 420352, 421434, 421723 

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Safety and Pollution Prevention. Washington, DC. March 24, 2016

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Office of Pesticide Programs, Office of Chemical Safety and Pollution Prevention. Washington,

DC. March 24, 2016
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Wildlife Service, Atlanta, Georgia. 23 pp.

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and Wildlife Service Ecological Services Region 6 and Region 2.
34

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First Revision. U.S. Fish and Wildlife Service, Southwest Region. Albuquerque, NM, URL: 

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_Plan_24Dec2012.pdf

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townsendii virginianus) 

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35

Appendix 1

Threatened and Endangered Species in Alabama, Georgia, Kentucky, Michigan, North 

Carolina, South Carolina, and Texas

Common Name Scientific Name Taxon

Indiana bat Myotis sodalis Mammal

West Indian Manatee Trichechus manatus Mammal

Finback whale Balaenoptera physalus Mammal

Humpback whale Megaptera novaeangliae Mammal

Gray bat Myotis grisescens Mammal

Canada Lynx Lynx canadensis Mammal

Louisiana black bear Ursus americanus luteolus Mammal

Carolina northern flying squirrel Glaucomys sabrinus coloratus Mammal

Whooping crane Grus americana Bird

Eskimo curlew Numenius borealis Bird

Kirtland's Warbler Setophaga kirtlandii Bird

Red-cockaded woodpecker Picoides borealis Bird

Wood stork Mycteria americana Bird

Piping Plover Charadrius melodus Bird

Least tern Sterna antillarum Bird

Black-capped Vireo Vireo atricapilla Bird

Lesser Prairie-Chicken Tympanuchus pallidicinctus Bird

Hawksbill sea turtle Eretmochelys imbricata Reptile

Leatherback sea turtle Dermochelys coriacea Reptile

Kemp's ridley sea turtle Lepidochelys kempii Reptile

Green sea turtle Chelonia mydas Reptile

Alabama red-belly turtle Pseudemys alabamensis Reptile

Copperbelly water snake Nerodia erythrogaster neglecta Reptile

Gopher tortoise Gopherus polyphemus Reptile

Snail darter Percina tanasi Fish

Spotfin Chub Erimonax monachus Fish

Slackwater darter Etheostoma boschungi Fish

Gulf sturgeon Acipenser oxyrinchus desotoi Fish

Amber darter Percina antesella Fish

Conasauga logperch Percina jenkinsi Fish

Blackside dace Phoxinus cumberlandensis Fish

Boulder darter Etheostoma wapiti Fish

Cumberland darter Etheostoma susanae Fish

Arkansas River shiner Notropis girardi Fish

Blue shiner Cyprinella caerulea Fish

Smalleye Shiner Notropis buccula Fish

Pallid sturgeon Scaphirhynchus albus Fish

Duskytail darter Etheostoma percnurum Fish

Cumberland bean (pearlymussel) Villosa trabalis Bivalve
36

purple cat's paw (=purple cat's paw 

pearlymussel) Epioblasma obliquata obliquata Bivalve

Alabama lampmussel Lampsilis virescens Bivalve

Pale lilliput (pearlymussel) Toxolasma cylindrellus Bivalve

Cumberland monkeyface (pearlymussel) Quadrula intermedia Bivalve

Pink mucket (pearlymussel) Lampsilis abrupta Bivalve

Dromedary pearlymussel Dromus dromas Bivalve

Littlewing pearlymussel Pegias fabula Bivalve

White wartyback (pearlymussel) Plethobasus cicatricosus Bivalve

Finerayed pigtoe Fusconaia cuneolus Bivalve

Rough pigtoe Pleurobema plenum Bivalve

Shiny pigtoe Fusconaia cor Bivalve

Orangefoot pimpleback (pearlymussel) Plethobasus cooperianus Bivalve

Fat pocketbook Potamilus capax Bivalve

Spectaclecase (mussel) Cumberlandia monodonta Bivalve

Southern combshell Epioblasma penita Bivalve

Rayed Bean Villosa fabalis Bivalve

Clubshell Pleurobema clava Bivalve

Cumberlandian combshell Epioblasma brevidens Bivalve

Appalachian elktoe Alasmidonta raveneliana Bivalve

Alabama (=inflated) heelsplitter Potamilus inflatus Bivalve

Orangenacre mucket Lampsilis perovalis Bivalve

Oyster mussel Epioblasma capsaeformis Bivalve

Slabside Pearlymussel Pleuronaia dolabelloides Bivalve

Stirrupshell Quadrula stapes Bivalve

Fanshell Cyprogenia stegaria Bivalve

Finelined pocketbook Lampsilis altilis Bivalve

Northern riffleshell Epioblasma torulosa rangiana Bivalve

Ovate clubshell Pleurobema perovatum Bivalve

Southern clubshell Pleurobema decisum Bivalve

Triangular Kidneyshell Ptychobranchus greenii Bivalve

Alabama moccasinshell Medionidus acutissimus Bivalve

Coosa moccasinshell Medionidus parvulus Bivalve

Southern pigtoe Pleurobema georgianum Bivalve

Snuffbox mussel Epioblasma triquetra Bivalve

Rabbitsfoot Quadrula cylindrica cylindrica Bivalve

Georgia pigtoe Pleurobema hanleyianum Bivalve

Fluted kidneyshell Ptychobranchus subtentum Bivalve

Sheepnose Mussel Plethobasus cyphyus Bivalve

Anthony's riversnail Athearnia anthonyi Gastropod

Karner blue butterfly Lycaeides melissa samuelis Insect

Mitchell's satyr Butterfly Neonympha mitchellii mitchellii Insect

American burying beetle Nicrophorus americanus Insect

Hine's emerald dragonfly Somatochlora hineana Insect

Spruce-fir moss spider Microhexura montivaga Arachnid
37

Short's bladderpod Physaria globosa Dicot

Price's potato-bean Apios priceana Dicot

Braun's rock-cress Arabis perstellata Dicot

Cumberland rosemary Conradina verticillata Dicot

No common name Geocarpon minimum Dicot

Spreading avens Geum radiatum Dicot

Small whorled pogonia Isotria medeoloides Monocot

Short's goldenrod Solidago shortii Dicot

Cumberland sandwort Arenaria cumberlandensis Dicot

Pitcher's thistle Cirsium pitcheri Dicot

Leafy prairie-clover Dalea foliosa Dicot

Roan Mountain bluet Hedyotis purpurea var. montana Dicot

Dwarf lake iris Iris lacustris Monocot

Pondberry Lindera melissifolia Dicot

Eastern prairie fringed orchid Platanthera leucophaea Monocot

Harperella Ptilimnium nodosum Dicot

American chaffseed Schwalbea americana Dicot

Large-flowered skullcap Scutellaria montana Dicot

Blue Ridge goldenrod Solidago spithamaea Dicot

Tennessee yellow-eyed grass Xyris tennesseensis Monocot

Virginia spiraea Spiraea virginiana Dicot

Running buffalo clover Trifolium stoloniferum Dicot

Lakeside daisy Hymenoxys herbacea Dicot

Morefield's leather flower Clematis morefieldii Dicot

Whorled Sunflower Helianthus verticillatus Dicot

American hart's-tongue fern

Asplenium scolopendrium var. 

americanum Ferns

Louisiana quillwort Isoetes louisianensis Ferns

Rock gnome lichen Gymnoderma lineare Lichen

Red wolf Canis rufus Mammal

North Atlantic Right Whale Eubalaena glacialis Mammal

Sperm whale Physeter catodon (=macrocephalus) Mammal

Gulf Coast jaguarundi

Herpailurus (=Felis) yagouaroundi 

cacomitli Mammal

Virginia big-eared bat

Corynorhinus (=Plecotus) townsendii 

virginianus Mammal

Ocelot Leopardus (=Felis) pardalis Mammal

Perdido Key beach mouse Peromyscus polionotus trissyllepsis Mammal

Alabama beach mouse Peromyscus polionotus ammobates Mammal

Mexican long-nosed bat Leptonycteris nivalis Mammal

Attwater's greater prairie-chicken Tympanuchus cupido attwateri Bird

Bachman's warbler (=wood) Vermivora bachmanii Bird

Northern aplomado falcon Falco femoralis septentrionalis Bird

Mexican spotted owl Strix occidentalis lucida Bird

Roseate tern Sterna dougallii dougallii Bird
38

Golden-cheeked warbler (=wood) Dendroica chrysoparia Bird

Southwestern willow flycatcher Empidonax traillii extimus Bird

Loggerhead sea turtle Caretta caretta Reptile

Flattened musk turtle Sternotherus depressus Reptile

Eastern indigo snake Drymarchon corais couperi Reptile

Texas blind salamander Typhlomolge rathbuni Amphibian

Houston toad Bufo houstonensis Amphibian

Red Hills salamander Phaeognathus hubrichti Amphibian

San Marcos salamander Eurycea nana Amphibian

Barton Springs salamander Eurycea sosorum Amphibian

Frosted Flatwoods salamander Ambystoma cingulatum Amphibian

Jollyville Plateau salamander Eurycea tonkawae Amphibian

Georgetown salamander Eurycea naufragia Amphibian

Salado salamander Eurycea chisholmensis Amphibian

Austin blind salamander Eurycea waterlooensis Amphibian

Reticulated flatwoods salamander Ambystoma bishopi Amphibian

Big Bend gambusia Gambusia gaigei Fish

Clear Creek gambusia Gambusia heterochir Fish

Comanche Springs pupfish Cyprinodon elegans Fish

Shortnose sturgeon Acipenser brevirostrum Fish

Fountain darter Etheostoma fonticola Fish

Watercress darter Etheostoma nuchale Fish

Pecos gambusia Gambusia nobilis Fish

Alabama cavefish Speoplatyrhinus poulsoni Fish

Pygmy Sculpin Cottus paulus (=pygmaeus) Fish

Cape Fear shiner Notropis mekistocholas Fish

Waccamaw silverside Menidia extensa Fish

San Marcos gambusia Gambusia georgei Fish

Leon Springs pupfish Cyprinodon bovinus Fish

Alabama sturgeon Scaphirhynchus suttkusi Fish

Cherokee darter Etheostoma scotti Fish

Devils River minnow Dionda diaboli Fish

Cahaba shiner Notropis cahabae Fish

Palezone shiner Notropis albizonatus Fish

Sharpnose Shiner Notropis oxyrhynchus Fish

Sunfish, spring pygmy Elassoma alabamae Fish

Goldline darter Percina aurolineata Fish

Relict darter Etheostoma chienense Fish

Etowah darter Etheostoma etowahae Fish

Vermilion darter Etheostoma chermocki Fish

Smalltooth sawfish Pristis pectinata Fish

Rush Darter Etheostoma phytophilum Fish

Yellow blossom (pearlymussel) Epioblasma florentina florentina Bivalve

Ring pink (mussel) Obovaria retusa Bivalve

Flat pigtoe Pleurobema marshalli Bivalve
39

Heavy pigtoe Pleurobema taitianum Bivalve

Tar River spinymussel Elliptio steinstansana Bivalve

Choctaw bean Villosa choctawensis Bivalve

Cumberland elktoe Alasmidonta atropurpurea Bivalve

Alabama pearlshell Margaritifera marrianae Bivalve

Cracking pearlymussel Hemistena lata Bivalve

James spinymussel Pleurobema collina Bivalve

Altamaha Spinymussel Elliptio spinosa Bivalve

Dwarf wedgemussel Alasmidonta heterodon Bivalve

Southern acornshell Epioblasma othcaloogensis Bivalve

Purple bankclimber (mussel) Elliptoideus sloatianus Bivalve

Upland combshell Epioblasma metastriata Bivalve

Round Ebonyshell Fusconaia rotulata Bivalve

Carolina heelsplitter Lasmigona decorata Bivalve

Southern kidneyshell Ptychobranchus jonesi Bivalve

Oval pigtoe Pleurobema pyriforme Bivalve

Narrow pigtoe Fusconaia escambia Bivalve

Shinyrayed pocketbook Lampsilis subangulata Bivalve

Southern sandshell Hamiota (=Lampsilis) australis Bivalve

Fat three-ridge (mussel) Amblema neislerii Bivalve

Dark pigtoe Pleurobema furvum Bivalve

Gulf moccasinshell Medionidus penicillatus Bivalve

Ochlockonee moccasinshell Medionidus simpsonianus Bivalve

Chipola slabshell Elliptio chipolaensis Bivalve

Fuzzy pigtoe Pleurobema strodeanum Bivalve

Tapered pigtoe Fusconaia burkei Bivalve

Noonday globe Patera clarki nantahala Gastropod

Phantom springsnail Pyrgulopsis texana Gastropod

Phantom tryonia Tryonia cheatumi Gastropod

Armored snail Pyrgulopsis (=Marstonia) pachyta Gastropod

Pecos assiminea snail Assiminea pecos Gastropod

Diamond Y Spring snail Pseudotryonia adamantina Gastropod

Tulotoma snail Tulotoma magnifica Gastropod

Gonzales springsnail Tryonia circumstriata Gastropod

Lacy elimia (snail) Elimia crenatella Gastropod

Rough hornsnail Pleurocera foremani Gastropod

Cylindrical lioplax (snail) Lioplax cyclostomaformis Gastropod

Flat pebblesnail Lepyrium showalteri Gastropod

Painted rocksnail Leptoxis taeniata Gastropod

Plicate rocksnail Leptoxis plicata Gastropod

Round rocksnail Leptoxis ampla Gastropod

Slender campeloma Campeloma decampi Gastropod

Interrupted (=Georgia) Rocksnail Leptoxis foremani Gastropod

Hungerford's crawling water Beetle Brychius hungerfordi Insect

Coffin Cave mold beetle Batrisodes texanus Insect
40

Kretschmarr Cave mold beetle Texamaurops reddelli Insect

Tooth Cave ground beetle Rhadine persephone Insect

Comal Springs riffle beetle Heterelmis comalensis Insect

Comal Springs dryopid beetle Stygoparnus comalensis Insect

Saint Francis' satyr butterfly Neonympha mitchellii francisci Insect

[Unnamed] ground beetle Rhadine infernalis Insect

Helotes mold beetle Batrisodes venyivi Insect

[Unnamed] ground beetle Rhadine exilis Insect

Bee Creek Cave harvestman Texella reddelli Arachnid

Bone Cave harvestman Texella reyesi Arachnid

Tooth Cave pseudoscorpion Tartarocreagris texana Arachnid

Tooth Cave Spider Leptoneta myopica Arachnid

Cokendolpher Cave Harvestman Texella cokendolpheri Arachnid

Government Canyon Bat Cave Spider Neoleptoneta microps Arachnid

Madla's Cave Meshweaver Cicurina madla Arachnid

Robber Baron Cave Meshweaver Cicurina baronia Arachnid

Government Canyon Bat Cave Meshweaver Cicurina vespera Arachnid

Braken Bat Cave Meshweaver Cicurina venii Arachnid

Peck's cave amphipod Stygobromus (=Stygonectes) pecki Crustacean

Alabama cave shrimp Palaemonias alabamae Crustacean

Kentucky cave shrimp Palaemonias ganteri Crustacean

Diminutive Amphipod Gammarus hyalleloides Crustacean

Star cactus Astrophytum asterias Dicot

Pecos (=puzzle, =paradox) sunflower Helianthus paradoxus Dicot

Neches River rose-mallow Hibiscus dasycalyx Dicot

Kentucky glade cress Leavenworthia exigua laciniata Dicot

Fleshy-Fruit Gladecress Leavenworthia crassa Dicot

Zapata bladderpod Lesquerella thamnophila Dicot

Ashy dogweed Thymophylla tephroleuca Dicot

South Texas ambrosia Ambrosia cheiranthifolia Dicot

Little amphianthus Amphianthus pusillus Dicot

Tobusch fishhook cactus Sclerocactus brevihamatus ssp. tobuschii Dicot

Hairy rattleweed Baptisia arachnifera Dicot

Texas poppy-mallow Callirhoe scabriuscula Dicot

Small-anthered bittercress Cardamine micranthera Dicot

Nellie cory cactus Coryphantha minima Dicot

Bunched cory cactus Coryphantha ramillosa Dicot

Sneed pincushion cactus Coryphantha sneedii var. sneedii Dicot

Black lace cactus Echinocereus reichenbachii var. albertii Dicot

Davis' green pitaya Echinocereus viridiflorus var. davisii Dicot

Lloyd's Mariposa cactus Echinomastus mariposensis Dicot

Johnston's frankenia Frankenia johnstonii Dicot

Dwarf-flowered heartleaf Hexastylis naniflora Dicot

Slender rush-pea Hoffmannseggia tenella Dicot

Lyrate bladderpod Lesquerella lyrata Dicot
41

Walker's manioc Manihot walkerae Dicot

Mohr's Barbara button Marshallia mohrii Dicot

Texas trailing phlox Phlox nivalis ssp. texensis Dicot

Little Aguja (=Creek) Pondweed Potamogeton clystocarpus Monocot

Hinckley oak Quercus hinckleyi Dicot

Miccosukee gooseberry Ribes echinellum Dicot

Bunched arrowhead Sagittaria fasciculata Monocot

Green pitcher-plant Sarracenia oreophila Dicot

Fringed campion Silene polypetala Dicot

White-haired goldenrod Solidago albopilosa Dicot

Gentian pinkroot Spigelia gentianoides Dicot

Navasota ladies'-tresses Spiranthes parksii Monocot

Texas snowbells Styrax texanus Dicot

Cooley's meadowrue Thalictrum cooleyi Dicot

Persistent trillium Trillium persistens Monocot

Texas wild-rice Zizania texana Monocot

Large-fruited sand-verbena Abronia macrocarpa Dicot

Sensitive joint-vetch Aeschynomene virginica Dicot

Terlingua Creek cat's-eye Cryptantha crassipes Dicot

Smooth coneflower Echinacea laevigata Dicot

Chisos Mountain hedgehog Cactus Echinocereus chisoensis var. chisoensis Dicot

Schweinitz's sunflower Helianthus schweinitzii Dicot

Swamp pink Helonias bullata Monocot

Heller's blazingstar Liatris helleri Dicot

Rough-leaved loosestrife Lysimachia asperulaefolia Dicot

Michigan monkey-flower Mimulus michiganensis Dicot

Canby's dropwort Oxypolis canbyi Dicot

Michaux's sumac Rhus michauxii Dicot

Alabama canebrake pitcher-plant Sarracenia rubra alabamensis Dicot

Mountain sweet pitcher-plant Sarracenia rubra ssp. jonesii Dicot

Houghton's goldenrod Solidago houghtonii Dicot

Seabeach amaranth Amaranthus pumilus Dicot

White bladderpod Lesquerella pallida Dicot

Relict trillium Trillium reliquum Monocot

Texas prairie dawn-flower Hymenoxys texana Dicot

Alabama leather flower Clematis socialis Dicot

Mountain golden heather Hudsonia montana Dicot

Kral's water-plantain Sagittaria secundifolia Monocot

Texas ayenia Ayenia limitaris Dicot

Texas Golden Gladecress Leavenworthia texana Dicot

White irisette Sisyrinchium dichotomum Monocot

Golden sedge Carex lutea Monocot

Florida torreya Torreya taxifolia Conf/cycds

Black spored quillwort Isoetes melanospora Ferns

Mat-forming quillwort Isoetes tegetiformans Ferns
42

Alabama streak-sorus fern Thelypteris pilosa var. alabamensis Ferns

False killer whale Pseudorca crassidens Mammal
43

Appendix 2

Listed Species Rationale for NO Effects When Action Area is Limited to Treated 

Agricultural Field –Accounting for Spray Drift Mitigation Labeling Restrictions. 

The spray drift (in-field buffer) and rainfast mitigations discussed in the cotton section 3 ecological risk 

assessment (D404823), the concurrently issued soybean addendum (D426789) and at the beginning of 

this assessment are anticipated to restrict dicamba and DCSA residues above any threshold toxicity values 

to the agricultural field. Therefore, the following table describes the habitat and rationale for all listed 

species that were determined to not use cotton and soybean fields or resources that may overlap with 

dicamba DGA uses.

Species Habitat Rationale Source 

Animals

Alabama beach 

mouse 

(Peromyscus 

polionotus 

ammobates)

Coastal sand dunes and

coastal scrub (USFWS 1987, 

p. 2), (USFWS 2007, p. 

4330); primary, secondary 

and interior or scrub dunes 

(USFWS 2009, p. 4, 11)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with sand 

dunes of coastal 

scrub. 

USFWS. 1987. Recovery plan for 

the Choctawhatchee, Perdido Key 

and Alabama Beach Mouse. U.S. 

Fish and Wildlife Service, Atlanta, 

Georgia. 45 pp. Available online 

at: 

http://ecos.fws.gov/docs/recovery_

plan/870812.pdf

Federal Register. 2007. 

Department of the Interior, Fish 

and Wildlife Service. 50 CFR Part 

17. Endangered and Threatened 

Wildlife and Plants; Designation 

of Critical Habitat for the Alabama 

Beach Mouse. Vol. 72, No. 19. 

January 30, 2007. Available 

online at: 

http://www.gpo.gov/fdsys/pkg/FR2007-01-30/pdf/07-

270.pdf#page=1

USFWS. 2009. Alabama beach 

mouse (Peromyscus polionotus 

ammobates, Bowen 1968), 5-Year 

Review: Summary and Evaluation. 

Daphne, Alabama. 34 pp. 

Available online at: 

http://ecos.fws.gov/docs/five_year

_review/doc2996.pdf.
44

Species Habitat Rationale Source 

Alabama Redbelly turtle

(Pseudemys 

alabamensis)

Streams, lakes and sloughs 

(USFWS, 1990, p. 1)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with 

streams, likes or 

sloughs.

USFWS. 1990. Recovery Plan for 

the Alabama Red-bellied Turtle. 

United States Fish and Wildlife 

Service. Available online at: 

http://ecos.fws.gov/docs/recovery_

plan/900108.pdf

Austin blind 

salamander 

(Eurycea 

waterlooensis)

Strictly aquatic and spend 

their entire lives 

submersed in water from the 

Barton 

Springs Segment of the 

Edwards Aquifer 

(Hillis et al. 2001, p. 

273)(Page 51340)

Rocky substrate, 

consisting of boulder, 

cobble, and 

gravel, with interstitial 

spaces that have 

minimal sediment (Page 

51341)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with water 

bodies. 

USFWS 2013. Designation of 

Critical Habitat for the Austin 

Blind and Jollyville Plateau 

Salamanders; Final Rule

Bachman's 

warbler 

(Vermivora 

bachmanii)

Breeds in palustrine forested 

wetlands; seen near longleaf 

pine forest near brackish 

marsh. (USFWS 2007)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with 

wetlands. 

USFWS 2007. Five Year Review: 

http://ecos.fws.gov/docs/five_year

_review/doc1037.pdf

Barton Springs 

salamander 

(Eurycea 

sosorum)

Aquatic.

Stenothermal spring flows, 

substrates are mixtures of 

gravel, cobble, aquatic 

plants, leaf litter and are free 

of sediment.

Pools and spring runs, 

subsurface portions of the 

aquifer (within water-bearing 

karst formations).

Found under boulder, cobble, 

gravel and plant (aquatic 

plants, leaf litter, woody 

debris) substrates.

(USFWS 2005)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies. 

USFWS. 2005. Barton Springs 

salamander (Eurycea sosorum) 

recovery plan. United States Fish 

and Wildlife Service. Available 

online at: 

http://ecos.fws.gov/docs/recovery_

plan/050921.pdf.
45

Species Habitat Rationale Source 

Bean, 

Cumberland 

(pearlymussel) 

(Villosa 

trabalis)

Restricted typically to 

tributary streams of the upper 

reaches of the Tennessee and 

Cumberland Rivers. This 

species is most often found 

associated with clean, fast 

flowing water in stable 

substrate, which contains 

relatively firm rubble, gravel, 

and sand swept-free from 

siltation. Typically, V.

trabalis is found buried in 

shallow riffle and shoal 

areas, often located under 

large rocks that must be 

removed by hand to inspect 

the habitat underneath. Ideal 

habitat conditions are 

difficult to find; much of the 

historical habitat for the 

species has likely been 

degraded and may be 

incapable of currently 

harboring the species (US 

FWS 2010, p. 7).

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 2010. 5 Year Review. 

http://ecos.fws.gov/docs/five_year

_review/doc3244.pdf

Rayed Bean 

(Villosa fabalis)

Generally known from 

smaller, headwater creeks, 

but occurrence records exist 

from larger rivers. Usually 

found in or near shoal or 

riffle areas and in the 

shallow, wave-washed areas 

of glacial lakes.

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 2012. Endangered and 

Threatened Wildlife and Plants; 

Determination of Endangered 

Status for the Rayed Bean and 

Snuffbox Mussels Throughout 

Their Ranges. 

http://www.gpo.gov/fdsys/pkg/FR2012-02-14/pdf/2012-2940.pdf

Black-capped 

vireo (Vireo 

atricapilla)

Insect-eating, migratory 

songbird. Arrive in Texas 

from mid-March to midApril, while those in 

Oklahoma arrive 

approximately 10 days later. 

Breeding habitat is quite 

variable across its range, but 

is generally shrublands with 

a distinctive patchy structure. 

The shrub vegetation is 

mostly deciduous and 

generally extends from the 

ground to about six feet 

above ground and covers 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with 

shrublands 

associated with 

rocky gullies, edges 

of ravines, or 

eroded slopes. 

USFWS. 2007. Five Year Review. 

http://ecos.fws.gov/docs/five_year

_review/doc1073.pdf 

USFWS. 1991. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/910930h.pdf 
46

Species Habitat Rationale Source 

about 30 to 60% of the total 

area. Open grassland 

separates the clumps of 

shrubs. (US FWS 2007, p. 7) 

From Oklahoma through 

most of Texas, this type of 

vegetational configuration 

occurs most frequently on 

rocky substrates with 

shallow soils, in rocky 

gullies, on edges of ravines, 

and on eroded slopes. (US 

FWS 1991, p. 20)

Butterfly, 

Karner blue 

(Lycaeides 

melissa 

samuelis)

Habitat is successional areas 

with wild lupines, such as 

open areas in and near forest 

stands, along with old fields, 

highway and powerline 

rights-of-way, and remnant 

barrens and savannas, having 

a broken or scattered tree or 

tall shrub canopy (US FWS, 

2003. pp.28-30)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with 

successional areas 

with lupines or 

other wildflowers.

USFWS. 2003. Recovery Plan.

http://ecos.fws.gov/docs/recovery_

plan/030919.pdf

Butterfly, 

Mitchell's satyr 

(Neonympha 

mitchellii 

mitchellii)

Mitchell’s satyr habitat is 

best characterized as a sedgedominated fen community; 

Known habitats are all 

peatlands but range along a 

continuum from prairie/bog 

fen to sedge meadow/swamp. 

However, certain attributes at 

each site remain fairly 

constant. All historical and 

active habitats have a 

herbaceous community 

which is dominated by 

sedges, usually Carex stricta, 

with scattered deciduous 

and/or coniferous trees, most 

often L. laricina or Juniperus 

virginiana (red cedar) (US 

FWS 1998, pp. 11-12). 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with 

wetlands or areas 

with sedge 

communities. 

USFWS 1998. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/980402.pdf

Chub, spotfin 

(Erimonax 

monachus)

The species is an insectivore, 

feeding diurnally presumably 

by both sight and taste in 

benthic areas of slow to swift 

current over various 

substrates with little siltation. 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1983. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/831121.pdf
47

Species Habitat Rationale Source 

Streams may range from 15-

60 m in width and, where 

occupied, 0.3-10.0 m in 

depth. Water temperature in 

their summer habitat usually 

reaches greater than 20°C, 

and submerged macrophytes 

are usually absent, 

occasionally common. The 

species has been observed 

associated with sand, gravel, 

rubble, boulder, and bedrock 

substrates (Jenkins and 

Burkhead, 1982) (US FWS 

1983, p. 15). 

Clubshell 

(Pleurobema 

clava)

Clubshell is generally found 

in clean, coarse sand and 

gravel in runs, often just 

downstream of a riffle, and 

cannot tolerate mud or 

slackwater conditions 

(USFWS, 1994).

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1994. Recovery Plan.

http://ecos.fws.gov/docs/recovery_

plan/940921.pdf

Clubshell, ovate 

(Pleurobema 

perovatum)

Sand/gravel shoals and runs 

of small rivers and large 

streams (US FWS 2000, p. 

56)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 2000. Recovery Plan.

http://ecos.fws.gov/docs/recovery_

plan/001117.pdf

Clubshell, 

southern 

(Pleurobema 

decisum)

Sand/gravel shoals and runs 

of small rivers and large 

streams (US FWS 2000, p. 

58)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 2000. Recovery Plan.

http://ecos.fws.gov/docs/recovery_

plan/001117.pdf

Combshell, 

Cumberlandian 

(Epioblasma 

brevidens)

This species inhabits 

medium-sized streams to 

large rivers on shoals and 

riffles in coarse, sand, gravel, 

cobble, and boulders. It is 

not associated with small 

stream habitats and tends not 

to extend as far upstream in 

tributaries (US FWS 2004, p. 

18). 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 2004. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/040524.pdf
48

Species Habitat Rationale Source 

Combshell,

southern 

(Epioblasma 

penita)

This species inhabits the 

Tombigbee River, which is a 

major western tributary of 

the Mobile Basin. It is 

characterized by an 

increasing number of sand 

and gravel shoals and 

decreasing channel size (US 

FWS, 1989, p. 1)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1989. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/891114e.pdf

Dace, blackside 

(Phoxinus 

cumberlandensi

s)

This species inhabits cool, 

small, upland streams with 

moderate flows. The fish is 

generally associated with 

undercut stream banks and 

large rocks, and it is usually 

found within well-vegetated 

watersheds with good 

riparian vegetation (US FWS 

1988, p. 6). 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1988. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/880817.pdf

Darter, amber 

(Percina 

antesella)

This species inhabits gentle 

riffle areas over sand, gravel, 

and cobble substrates. 

Aquatic vegetation that 

develops in riffles provides 

habitat for feeding and cover 

(US FWS, 1986, p. 6). 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1986. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/860620.pdf

Darter, boulder 

(Etheostoma 

wapiti)

This species inhabits warmwater riverine environments 

and has been found only in 

moderate to fast current over 

boulder/slab rock substrate in 

water over 2 feet deep (US 

FWS, 1989, p. 2). 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1989. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/890727.pdf

Darter, 

Cumberland 

(Etheostoma 

susanae)

This species inhabits pools or 

shallow runs of low to 

moderate gradient sections of 

streams with stable sand, silt, 

or sand-covered bedrock 

substrates (US FWS, 2012, 

p. 63605). 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 2012. Federal Register 

Notice: Designated Critical 

Habitat. 

http://www.gpo.gov/fdsys/pkg/FR2012-10-16/pdf/2012-24468.pdf

Darter, 

duskytail 

(Etheostoma 

percnurum)

This species inhabits rocky 

areas in gently flowing 

shallow pools and runs in 

large creeks and moderately 

large rivers in the Tennessee 

and Cumberland River 

Systems (US FWS, 1994, 

Executive Summary). 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1994. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/duskytaildarter_RP.pdf
49

Species Habitat Rationale Source 

Darter, 

slackwater 

(Etheostoma 

boschungi)

Nonbreeding habitat is small 

to moderately large streams. 

The current is usually slow, 

and under normal conditions, 

the flow ranges from still to 

0.34 m/sec. In small streams, 

the darters show no position 

preference; however, in large 

streams they seem to confine 

themselves to near the banks 

or to undercuts in the banks. 

They also occur on gravel 

infiltrated with silt, on silt 

and mud, or in a combination 

of these. The breeding 

habitat is seepage water in 

open fields and woods (US 

FWS, 1984, pp. 7-8).

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1984. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/840308.pdf

Darter, snail 

(Percina tanasi)

This species occupies seven 

of nine tributaries of the 

upper Tennessee River in 

Alabama, Georgia and 

Tennessee (US FWS, 2013, 

p. 10). 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 2013. Five Year Review. 

http://ecos.fws.gov/docs/five_year

_review/doc4136.pdf

Dragonfly, 

Hine's emerald 

(Somatochlora 

hineana)

The Hine’s emerald 

dragonfly occupies grass 

marshes and sedge meadows 

fed primarily by water from 

a mineral source or fens. 

Two important 

characteristics of the habitat 

appear to be groundwaterfed, shallow water slowly 

flowing through vegetation, 

and underlying dolomitic or 

limestone bedrock. Parts of 

the aquatic channels are 

typically covered by 

vegetation such as cattails or 

sedges. Soils can range from 

organic muck to mineral 

soils like marl. Two other 

important components are 

areas of open vegetation for 

foraging and forests, trees or 

shrubs that provide shaded 

areas for perching or 

roosting. Nearby adjacent 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with grass 

marshes, sedge 

meadows, forested 

areas, or other 

habitat where the 

Hine’s emerald 

dragonfly is 

expected to be 

found.

USFWS. 2001. Recovery Plan.

http://ecos.fws.gov/docs/recovery_

plan/010927.pdf
50

Species Habitat Rationale Source 

forests may be deciduous 

(Illinois) or conifer 

(Wisconsin and Michigan).

Larvae are usually found in 

small flowing streamlets 

within cattail marshes, sedge 

meadows, and hummocks. 

Places with silt, leaf litter, 

and decaying grasses as a 

substrate are often used (US 

FWS, 2001, p. 15-16.).

Critical Habitat of 26,531 

acres have been designated 

in Michigan, Illinois, 

Wisconsin, and Missouri. 

Almost half of this is 

Mackinac County, MI.

Elktoe, 

Appalachian 

(Alasmidonta 

raveneliana)

This species has been 

reported from relatively 

shallow medium-sized creeks 

and rivers with cool, welloxygenated, and moderateto fast-flowing water. It has 

been observed in gravelly 

substrata, often mixed with 

cobble and boulders; in 

cracks in bedrock; and 

occasionally in relatively 

silt-free, coarse, sandy 

substrata (US FWS, 1996, 

Executive Summary). 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1996. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/960826.pdf

False killer 

whale 

(Pseudorca 

crassidens)

Deep water: “They prefer 

tropical to temperate waters 

that are deeper than 

3,300 feet (1000 m).”

The proposed 

dicamba DGA uses 

are not expected to 

overlap with 

coastal waters. 

http://www.nmfs.noaa.gov/pr/speci

es/mammals/cetaceans/falsekillerw

hale.htm

Fanshell 

(Cyprogenia 

stegaria)

The fanshell inhabits gravel 

substrates in medium to large 

rivers of the Ohio River 

basin (US FWS, 1991, 

Executive Summary).

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1991. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/910709.pdf
51

Species Habitat Rationale Source 

Flattened musk 

turtle 

(Sternotherus 

depressus)

Streams, Lake margins 

(USFWS 1990, p 3); spend 

most of their time in benthic 

habitats (USFWS 1990, p 5)

Optimum habitat includes 

creeks and small rivers with 

vegetated areas with depth of 

3 - 600 cm (USFWS 1990, p 

3)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks or 

other water bodies. 

USFWS. 1990. Recovery Plan for 

the Flattened Musk Turtle. United 

States Fish and Wildlife Service. 

Available online at: 

http://ecos.fws.gov/docs/recovery_

plan/900226.pdf

Frosted 

Flatwoods 

salamander 

(Ambystoma 

cingulatum)

Fire-maintained, opencanopied, flatwoods and 

savannas dominated by 

longleaf pine (Pinus 

palustris), with naturally 

occurring slash pine (P. 

elliotti) in wetter areas.

Adults spend most of their 

lives underground.

Breed in small, isolated 

ephemeral ponds (USFWS 

2009)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with 

flatwoods or 

savannas. 

USFWS 2009. Federal Register, 

vol. 74, No. 62. 50 CFR 17. 

Endangered and threatened 

wildlife and plants; determination 

of endangered status of reticulated 

flatwoods salamander; designation 

of critical habitat for frosted 

flatwoods salamander and 

reticulated flatwoods salamander. 

United States Fish and Wildlife 

Service. Available on line at: 

http://www.gpo.gov/fdsys/pkg/FR2009-02-10/pdf/E9-

2403.pdf#page=1

Georgetown 

salamander 

(Eurycea 

naufragia)

Aquatic.

The Northern Segment of the 

Edwards Aquifer, which is a 

karst aquifer characterized 

by open chambers such as 

caves, fractures, and other 

cavities that were formed 

either directly or indirectly 

by dissolution of subsurface 

rock formations. (USFWS 

2014, Pg. 10237)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with cave 

aquifers. 

USFWS 2014. Determination of 

Threatened Species Status for the 

Georgetown Salamander and 

Salado Salamander Throughout 

Their Ranges; Final Rule 

Golden-cheeked 

warbler 

(Dendroica 

chrysoparia)

Forest (USFWS 1992, p. 7) The proposed 

dicamba DGA uses 

are not expected to 

overlap with forest. 

USFWS 1992. Species specific 

recovery plan available on FWS 

website.

http://ecos.fws.gov/docs/recovery_

plan/920930f.pdf

Heelsplitter, 

Alabama 

(=inflated) 

(Potamilus 

inflatus)

This species prefers a soft, 

stable substrate in slow to 

moderate currents. It has 

been found in sand, mud, silt 

and sandy-gravel, but not in 

large or armored gravel (US 

FWS, 1993, Executive 

Summary). 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1993. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/930413.pdf
52

Species Habitat Rationale Source 

Jollyville 

Plateau

salamander 

(Eurycea 

tonkawae)

Jollyville Plateau 

salamanders are 

strictly aquatic and spend 

their entire 

lives submersed in water 

sourced from 

the Northern Segment of the 

Edwards 

Aquifer, the Trinity Aquifer, 

and local 

alluvium (loose 

unconsolidated soils) 

(COA 2001, pp. 3–4; Bowles 

et al. 2006, 

p. 112; Johns 2011, p. 5–6). 

(Page 51340)

Rocky substrate, 

consisting of boulder, 

cobble, and 

gravel, with interstitial 

spaces that have 

minimal sediment (Page 

51341)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks or 

other water bodies. 

USFWS 2013. Designation of 

Critical Habitat for the Austin 

Blind and Jollyville Plateau 

Salamanders; Final Rule

Kidneyshell, 

fluted 

(Ptychobranchu

s subtentum)

Associated with the 

Cumberland and Tennessee 

River drainages. Generally 

live embedded in the bottom 

of stable streams and other 

bodies of water, and within 

riffle areas of sufficient 

current velocities to remove 

finer sediments and provide 

well oxygenated waters (US 

FWS, 2013, p. 59560)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 2013. Federal Register 

Notice: Designation of Critical 

Habitat. 

http://www.gpo.gov/fdsys/pkg/FR2013-09-26/pdf/2013-23357.pdf

Kidneyshell, 

triangular 

(Ptychobranchu

s greenii)

Sand/gravel shoals and runs 

of small rivers and large 

streams (US FWS 2000, p. 

60)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 2000. Recovery Plan.

http://ecos.fws.gov/docs/recovery_

plan/850702.pdf

Lampmussel, 

Alabama 

(Lampsilis 

virescens)

This species inhabits sand 

and gravel substrates in small 

to medium sized streams (US 

FWS, 1985, p. 9). 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1985. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/850702.pdf
53

Species Habitat Rationale Source 

Lilliput, pale 

(pearlymussel) 

(Toxolasma 

cylindrellus)

This species is observed in 

clean, fast-flowing water in 

substrates that contain 

relatively firm rubble, gravel, 

and sand substrates swept 

free from siltation. These 

mussels are usually found 

buried in the substrate in 

shallow riffle and shoal areas 

(US FWS, 1984, p. 5). 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1984. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/840822.pdf

Loggerhead sea 

turtle (Caretta 

Caretta)

Ocean, Beaches, Neritic zone 

(NMFS 2009, p I-20)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with 

coastal waters. 

NMFS and USFWS. 2009. 

Recovery Plan for the Northwest 

Atlantic Population of the 

Loggerhead Sea Turtle, Second 

Revision. US Department of 

Commerce, National Oceanic and 

Atmospheric Administration, 

National Marine Fisheries Service 

and United States Fish and 

Wildlife Service. Available online 

at: 

http://ecos.fws.gov/docs/recovery_

plan/090116.pdf

Logperch, 

Conasauga 

(Percina 

jenkinsi)

This species has been 

collected in deep shuts and 

flowing pools with clear, 

clean gravel and mixed 

rubble substrates in areas 

with moderate to swift 

currents (US FWS, 1986, p. 

8).

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1986. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/860620.pdf

Lynx, Canada

(Lynx 

canadensis)

PCE: Boreal forest 

landscapes with large 

populations of snowshoe 

hares. Distribution and 

abundance of prey and 

microclimate influence 

movement, hunting behavior, 

and den and resting site 

locations. Areas with dense 

cover. 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with boreal 

forests. The lynx’s 

prey, snowshoe 

hares, also do not 

overlap with the 

proposed dicamba 

DGA use sites.

USFWS. 2014. Federal Register 

Notice: Designation of Critical 

Habitat

http://www.gpo.gov/fdsys/pkg/FR2014-09-12/pdf/2014-21013.pdf

Manatee, West 

Indian 

(Trichechus 

manatus)

This species lives in 

freshwater, brackish and 

marine habitats (US FWS, 

2001, Executive Summary). 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 2001. Recovery PlanThird Revision. 

http://ecos.fws.gov/docs/recovery_

plan/011030.pdf
54

Species Habitat Rationale Source 

Mexican longnosed bat 

(Leptonycteris 

nivalis)

The Mexican long-nosed bat 

has evolved an apparent 

mutualistic association with 

Agave sp. The bat is 

principally a nectar feeder, 

foraging on the flowers of 

Agave, and in some minor 

proportions consuming the 

pollen, fruits, and any 

incidental insects associated 

with the flowers. The bats 

occupy mid- to highelevational desert scrub, 

open conifer-oak woodlands, 

and pine forest habitats in the 

Upper Sonoran and 

Transition Life Zones. 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with the 

desert scrub, open 

conifer-oak 

woodlands and pine 

forest habitats of 

the bat. The bat’s 

major resource 

need, Agave plants 

are not expected to 

be on soybean and 

cotton fields. 

USFWS. 1994. Recovery Plan.

https://ecos.fws.gov/docs/recovery

_plan/940908.pdf

Mexican 

spotted owl 

(Strix 

occidentalis 

lucida)

Forest and canyonlands in 

SW U.S. (USFWS 2011, p. 

7).

The proposed 

dicamba DGA uses 

are not expected to 

overlap with forests 

or Canyonlands. 

USFWS 2011. Species specific 

recovery plan available on FWS 

website. 

http://ecos.fws.gov/docs/recovery_

plan/FR00000557-

%20BP031995%20Draft%20MSO

%20Recovery%20Plan%20First%

20Revision.pdf

Moccasinshell, 

Alabama 

(Medionidus 

acutissimus)

Inhabits sand/gravel/cobble 

shoals with moderate to 

strong currents in streams 

and small rivers. (US FWS 

2000, p. 51)

The proposed 

dicamba DGA uses

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 2000. Recovery Plan.

http://ecos.fws.gov/docs/recovery_

plan/001117.pdf

Moccasinshell, 

Coosa 

(Medionidus 

parvulus)

Inhabits sand/gravel/cobble 

shoals with moderate to 

strong currents in streams 

and small rivers. (US FWS 

2000, p. 52)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 2000. Recovery Plan.

http://ecos.fws.gov/docs/recovery_

plan/001117.pdf

Monkeyface, 

Cumberland 

(pearlymussel) 

(Quadrula 

intermedia)

This species is most often 

observed in clean-fastflowing water in substrates 

that contain relatively firm 

rubble, gravel, and sand 

substrates swept free from 

siltation. These mussels are 

usually found buried in the 

substrate in shallow riffle 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1984. Recovery Plan.

http://ecos.fws.gov/docs/recovery_

plan/840709b.pdf
55

Species Habitat Rationale Source 

and shoal areas (US FWS, 

1984, p. 9). 

Mucket, 

orangenacre 

(Lampsilis 

perovalis)

Currently restricted to high 

quality stream and small 

river habitat, the species is 

found on stable 

sand/gravel/cobble substrate 

in moderate to swift currents 

(US FWS 2000, p. 55)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 2000. Recovery Plan.

http://ecos.fws.gov/docs/recovery_

plan/001117.pdf

Mucket, pink 

(pearlymussel) 

(Lampsilis 

abrupta)

The pink mucket may still 

exist in stretches of the lower 

Ohio River (US FWS, 1985, 

p. 10).

The pink mucket habitat is 

large rivers at least 60 feet 

wide, where it occurs at 

depths up to 25 feet deep. 

Currents are typically 

moderate to fast and 

substrates range from silt to 

boulders, rubble, gravel, and 

sand (US FWS, 1985, p. 11). 

The species seems to have 

adapted to living in 

impounded waters, at least in 

the upper reaches where the 

water is flowing (US FWS, 

1985, p. 10).

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1985. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/pink%20mucket%20rp.pdf

Mussel, oyster 

(Epioblasma 

capsaeformis)

This species is generally 

adapted to live in the gravel 

shoals of free-flowing rivers 

and streams (US FWS, 2004, 

Executive Summary). 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 2004. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/040524.pdf

Mussel, 

sheepnose 

(Plethobasus 

cyphyus)

The sheepnose is a largerstream species occurring 

primarily in shallow shoal 

habitats with moderate to 

swift currents over coarse 

sand and gravel. Habitats 

with sheepnose may also 

have mud, cobble, and 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 2012. Federal Register 

Notice: Final Rule. 

http://www.gpo.gov/fdsys/pkg/FR2012-03-13/pdf/2012-5603.pdf
56

Species Habitat Rationale Source 

boulders. Sheepnose in 

larger rivers may occur at 

depths exceeding 6 m (US 

FWS, 2012, p 14916).

Mussel, 

snuffbox 

(Epioblasma 

triquetra)

The habitat is described as 

swift currents and riffles, and 

shoals and wave-washed 

shores of lakes over gravel 

and sand with occasional 

cobble and boulders. They 

generally burrow deep into 

the substrate (US FWS, 

2010, p 67554). This 

constitutes a wide diversity 

of habitats. However, they 

do not occur in impounded 

areas or reservoirs (except 

tailwaters) (US FWS, 2012, 

p 8652).

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 2010. Federal Register 

Notice: Listing.

http://www.gpo.gov/fdsys/pkg/FR2010-11-02/pdf/2010-

27413.pdf#page=2

USFWS. 2012. Federal Register 

Notice: Final Rule.

http://www.gpo.gov/fdsys/pkg/FR2012-02-14/pdf/2012-2940.pdf

North Atlantic 

Right Whale 

(Eubalaena 

glacialis)

The North Atlantic right 

whale primarily occurs in 

coastal or shelf waters, but 

may go into deeper waters. 

(NMFS 2004, p. v)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with 

coastal waters. 

NMFS. 2004. Recovery plan for 

the north Atlantic right whale 

(Eubalaena glacialis). Available 

online at: 

http://ecos.fws.gov/docs/recovery_

plan/whale_right_northatlantic.pdf

Northern 

aplomado 

falcon (Falco 

femoralis 

septentrionalis)

Open terrain with scattered 

trees or shrubs.

Found along yacca covered 

sand ridges in coastal prairies

Riparian woodlands in open 

grasslands

Desert grasslands (USFWS 

1990, p. 13). 

Recommend offfield status for row 

crop agriculture. 

According to the 

Aplomado 

Recovery Plan 

(USFWS 1990), 

suitable habitat 

contains of terrain 

with inter-tree 

distances of 15 to 

45 m with a mean 

of 30 m and a 

woody plant 

density of 0.48 

tree/ha. The 

suitable land covers 

include yuccacovered ridges of 

coastal prairies, 

USFWS 1990. Species specific 

recovery plan available on FWS 

website. 

http://ecos.fws.gov/docs/recovery_

plan/900608.pdf
57

Species Habitat Rationale Source 

grasslands, prairies, 

desert grasslands, 

and riparian 

wooded areas near 

open grasslands. 

While the recovery 

plan is not specific 

as to row crop 

usage by the 

species, additional 

information on 

monitored 

individual falcons 

in Texas indicated 

that the only 

agricultural 

association with 

foraging falcons is 

for grazing lands 

and for fallow 

agricultural fields. 

(Perez et al. 1996)

Pearlymussel, 

dromedary 

(Dromus 

dromas)

This species is most often 

observed in clean, fastflowing water in substrates 

that contain relatively firm 

rubble, gravel and sand 

substrates swept free from 

siltation. These mussels are 

usually found buried in the 

substrate in shallow riffle 

and shoal areas (US FWS, 

1984, p. 8). 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1984. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/840709c.pdf

Pearlymussel, 

littlewing 

(Pegias fabula)

This species inhabits small to 

medium, low turbidity, coolwater, high to moderate 

gradient streams in the 

Cumberland and Tennessee 

River basins (US FWS, 

1989, p. 5).

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1989. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/890922.pdf

Pearlymussel, 

Slabside 

(Pleuronaia 

dolabelloides)

Associated with the 

Cumberland and Tennessee 

River drainages. Generally 

live embedded in the bottom 

of stable streams and other 

bodies of water, and within 

riffle areas of sufficient 

current velocities to remove 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 2013. Federal Register 

Notice: Designation of Critical 

Habitat. 

http://www.gpo.gov/fdsys/pkg/FR2013-09-26/pdf/2013-23357.pdf
58

Species Habitat Rationale Source 

finer sediments and provide 

well oxygenated waters (US 

FWS, 2013, p. 59560)

Perdido Key 

beach mouse 

(Peromyscus 

polionotus 

trissyllepsis)

Coastal sand dunes & coastal 

scrub (USFWS 1987, p. 2); 

primary, secondary and 

interior or scrub dunes 

(USFWS 2007, p. 9)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with sand 

dunes or coastal 

scrub. 

USFWS. 1987. Recovery plan for 

the Choctawhatchee, Perdido Key 

and Alabama Beach Mouse. U.S. 

Fish and Wildlife Service, Atlanta, 

Georgia. 45 pp. Available online 

at: 

http://ecos.fws.gov/docs/recovery_

plan/870812.pdf.

USFWS. 2007. Perdido Key Beach 

Mouse (Peromyscus polionotus 

trissyllepsis), 5-Year Review: 

Summary and Evaluation. Panama 

City, Florida. 24 pp. Available 

online at: 

http://ecos.fws.gov/docs/five_year

_review/doc1081.pdf.

Pigtoe, 

finerayed 

(Fusconaia 

cuneolus)

This species is typically a 

riffle species that inhabits 

ford and shoal areas in freeflowing streams of moderate 

gradient (US FWS, 1984, p. 

7). 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1984. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/fine%20rayed%20recov%20p

lan.pdf

Pigtoe, Georgia 

(Pleurobema 

hanleyianum)

This species requires flowing 

water, stable stream channels 

with minimal sediment and 

algae growth, and adequate 

water quality. It also requires 

a host fish, which is currently 

unknown (US FWS, 2013, 

Executive Summary). 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 2013. Draft Recovery 

Plan. 

http://ecos.fws.gov/docs/recovery_

plan/Hartfield%20and%20Powell

%202013%20Draft%20Three%20

Mollusks%20RP%20062813.pdf

Pigtoe, rough 

(Pleurobema 

plenum)

The rough pigtoe habitat is 

medium to large rivers, 60 

feet or wider, in sand and 

gravel substrates. Very 

limited collection 

information suggests it 

occurs below spillways, in 

transition zones, and in sand 

and gravel substrates (US 

FWS, 1984, p. 8).

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1984. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/840806.pdf
59

Species Habitat Rationale Source 

Pigtoe, shiny 

Entire 

(Fusconaia cor)

This species is typically a 

riffle species, found along 

fords and shoals of clear, 

moderate to fast-flowing 

streams and rivers with 

stable substrate. It does not 

inhabit deep pools or 

impounded areas. This 

species is usually found wellburied in the substrate during 

most of the year and is more 

readily visible in early 

summer (US FWS, 1984, p. 

8). 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1984. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/840709d.pdf

Pigtoe, southern 

(Pleurobema 

georgianum)

Sand/gravel shoals and runs 

of small rivers and large 

streams (US FWS 2000, p. 

59)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 2000. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/001117.pdf

Pimpleback, 

orangefoot 

(pearlymussel) 

(Plethobasus 

cooperianus)

The 1984 Recovery Plan 

indicated that the orange-foot 

pimpleback was known from 

the Tennessee, Cumberland, 

and lower Ohio Rivers (US 

FWS, 1984. p. 2). The 

habitat is described as 

medium to large rivers in 

sand and gravel substrates. 

In the Ohio River it was 

collected from 15-29 feet 

depths, but may have lived in 

shallower riffles (US FWS, 

1984, p. 6).

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1984. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/840930b.pdf

Plover, piping 

except Great 

Lakes 

watershed 

(Charadrius

melodus)

The northern Great Plains 

DPS of the piping plover 

utilizes four types of habitats 

for breeding: alkali lakes 

and wetlands, inland lakes 

(Lake of the Woods), 

reservoirs, and rivers. Most 

breeding occurs along

alkali lakes and wetlands, 

where nesting sites are 

generally wide, gravelly, salt 

encrusted beaches with 

minimal vegetation. At 

inland lakes, they use barren 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with 

shorelines, beaches, 

and sandbars of 

rivers and alkali 

wetlands. 

USFWS. 2002. Federal Register 

Notice.

http://ecos.fws.gov/docs/federal_re

gister/fr3943.pdf
60

Species Habitat Rationale Source 

to sparsely vegetated islands, 

beaches, and peninsulas. 

Sparsely vegetated sandbars 

and reservoir shorelines are 

preferred in riverine systems 

(US FWS, 2002, p. 57640).

Pocketbook, fat 

(Potamilus 

capax)

The fat pocketbook is a large 

river species requiring 

flowing water and a stable 

substrate, which can vary 

widely but is most likely a 

mixture of sand, silt and 

clay. It occurs in water from 

a few inches deep to at least 

8 feet. Habitat includes 

drainage ditches. (US FWS, 

1989, p. 6). Populations 

have been found in larger 

rivers in the Ohio River 

system, and it may occur as

deep as 20 feet (US FWS, 

2012, p. 7-8). It can also 

tolerate periods of high 

suspended sediments (US 

FWS, 2012, p. 11).

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1989. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/891114c.pdf

USFWS. 2012. Five Year Review.

http://ecos.fws.gov/docs/recovery_

plan/891114c.pdf

Pocketbook, 

finelined 

(Lampsilis 

altilis)

Live embedded in the bottom 

sand, gravel, and/or cobble 

substrates of rivers and 

streams (US FWS 2004, p. 

40097). 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks or 

other water bodies. 

USFWS. 2004. Federal Register 

Notice: Designation of Critical 

Habitat. 

http://www.gpo.gov/fdsys/pkg/FR2004-07-01/pdf/04-

14279.pdf#page=1

Purple Cat's 

paw (=Purple 

Cat's paw 

pearlymussel) 

(Epioblasma 

obliquata 

obliquata)

Inhabits boulder to sandy 

substrates in large rivers of 

the Ohio River basin (US 

FWS 1992, Executive 

summary). 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1992. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/920310.pdf

Rabbitsfoot 

(Quadrula 

cylindrica 

cylindrica)

“Rabbits foot is primarily an 

inhabitant of small to 

medium sized streams and 

some larger rivers. It usually 

occurs in shallow water areas 

along the bank and adjacent 

runs and shoals with reduced 

water velocity." They have 

been reported in deep water 

runs up to 12 feet depth. 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 2012. Federal Register 

Notice.

http://www.gpo.gov/fdsys/pkg/FR2012-10-16/pdf/2012-24151.pdf
61

Species Habitat Rationale Source 

"Bottom substrates generally 

include gravel and sand" (US 

FWS, 2012, p. 63446).

Red Hills 

salamander 

(Phaeognathus 

hubrichti)

Mesic ravine slopes and bluff 

sides (facing North) with 

hardwood trees.

Burrows within siltstone.

Usually found on sites with 

loamy, friable topsoils 

(USFWS 1983)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1983. Recovery plan for 

the red hills salamander 

(Phaeognathus hubrichti Highton). 

United States Fish and Wildlife 

Service. Available online at: 

http://ecos.fws.gov/docs/recovery_

plan/831123.pdf

Reticulated 

flatwoods 

salamander 

(Ambystoma 

bishopi)

Aquatic and terrestrial.

Longleaf pine ecosystems 

(Coastal Plain in what were 

historically longleaf pinewiregrass flatwoods and 

savannas).

Adults spend most of their 

lives underground.

Breed in small, isolated 

ephemeral ponds. (USFWS 

2009)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS 2009. Federal Register, 

vol. 74, No. 26. 50 CFR 17. 

Endangered and threatened 

wildlife and plants; determination 

of endangered status of reticulated 

flatwoods salamander; designation 

of critical habitat for frosted 

flatwoods salamander and 

reticulated flatwoods salamander. 

United States Fish and Wildlife 

Service. Available on line at: 

http://www.gpo.gov/fdsys/pkg/FR2009-02-10/pdf/E9-

2403.pdf#page=1

Riffleshell, 

northern 

(Epioblasma 

torulosa 

rangiana)

The habitat of the riffleshell 

occurs in packed sand and 

gravel in riffles and runs, and 

also in the western basin of 

Lake Erie where there is 

sufficient wave action to 

produce continuously 

moving water (US FWS, 

1994, p. 18). FWS further 

describes the habitat as 

medium to large rivers where 

they are often associated 

with high water velocities, 

although they have also been 

documented in Lake Erie and 

in deep more slow-flowing 

rivers down to 20 feet (US 

FWS, 2009. p. 9).

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1994. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/940921.pdf

USFWS. 2009. Five Year Review. 

http://ecos.fws.gov/docs/five_year

_review/doc3284.pdf
62

Species Habitat Rationale Source 

Riversnail, 

Anthony's 

(Athearnia 

anthonyi)

This species is typically 

found in large streams on 

large submerged objects 

(e.g., rocks and logs) or 

gravelly substrata in 

relatively shallow, 

moderately to fast-flowing 

water (US FWS, 1997). 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1997. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/970813.pdf

Roseate tern 

(Sterna 

dougallii 

dougallii)

Rocky offshore islands with 

sparse vegetation; although 

Northeastern Roseate tern 

nest under vegetation or 

some other shelter (USFWS 

1993, p. 3).

The proposed 

dicamba DGA uses 

are not expected to 

overlap with 

offshore islands.

USFWS 1993. Species specific 

recovery plan available on FWS 

website.

http://ecos.fws.gov/docs/recovery_

plan/930924_v2.pdf

Salado 

salamander 

(Eurycea 

chisholmensis)

Aquatic.

The Northern Segment of the 

Edwards 

Aquifer, which is a karst 

aquifer characterized by 

open chambers such as 

caves, fractures, and other 

cavities that 

were formed either directly 

or indirectly 

by dissolution of subsurface 

rock 

formations. (USFWS 2014, 

Pg. 10237)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS 2014. Determination of 

Threatened Species Status for the 

Georgetown Salamander and 

Salado Salamander Throughout 

Their Ranges; Final Rule 

San Marcos 

salamander 

(Eurycea nana)

Aquatic

Spring Lake.

Found among aquatic plants 

on the bottom of the lake.

Found under stones in sand 

and gravel areas.

Must have flowing water 

(from springs flowing into 

Spring Lake). (USFWS 

1996)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1996. San Marcos and 

Comal Springs and associated 

aquatic ecosystems (Revised) 

recovery plan. United States Fish 

and Wildlife Service. Available 

online at: 

http://ecos.fws.gov/docs/recovery_

plan/960214.pdf

Sea turtle, green 

(Chelonia 

mydas)

Green turtles are primarily 

restricted to tropical and 

subtropical waters. In U.S. 

Atlantic and Gulf of Mexico 

waters, green turtles are 

found from

Massachusetts to Texas and 

in the U.S. Virgin Islands 

and Puerto Rico...Seagrasses 

are the principal dietary 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with 

coastal waters.

NMFS, NOAA. 1998. Federal 

Register Notice: Designated 

critical habitat.

http://ecos.fws.gov/docs/federal_re

gister/fr3295.pdf
63

Species Habitat Rationale Source 

component of juvenile and 

adult green turtles 

throughout the Wider 

Caribbean region (Bjorndal, 

1995). (NMFS, NOAA 1998, 

p. 46694)

Sea turtle, 

hawksbill 

(Eretmochelys 

imbricata)

The hawksbill turtle occurs 

in tropical and subtropical 

waters of the Atlantic, 

Pacific, and Indian Oceans. 

Coral reefs, like those found 

in the waters surrounding 

Mona and Monito Islands, 

are widely recognized as the 

primary foraging habitat of 

juvenile, subadult, and adult 

hawksbill turtles. This 

habitat association is directly 

related to the species’ highly 

specific diet of sponges 

(Meylan, 1988). Hawksbills 

depend on coral reefs for 

food and shelter; therefore, 

the condition of reefs directly 

affects the hawksbill’s wellbeing. (NMFS, NOAA 

1998, p. 46695)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with 

coastal waters.

NMFS, NOAA. 1998. Federal 

Register Notice: Designated 

critical habitat. 

http://ecos.fws.gov/docs/federal_re

gister/fr3295.pdf

Sea turtle, 

Kemp's ridley 

(Lepidochelys 

kempii)

This life history pattern is 

characterized by three basic 

ecosystem zones: (1) 

Terrestrial zone 

(supralittoral) - the nesting 

beach where both oviposition 

and embryonic development 

occur; (2) Neritic zone - the 

nearshore (including bays 

and sounds) marine 

environment (from the 

surface to the sea floor) 

where water depths do not 

exceed 200 meters, including 

the continental shelf; and (3) 

Oceanic zone - the vast open 

ocean environment (from the 

surface to the sea floor) 

where water depths are 

greater than 200 meters. 

(NMFS, NOAA 2011, p. I-8)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with 

coastal waters.

NMFS, NOAA. 2011. Bi-national 

recovery plan for the kemp's ridley 

sea turtle.

http://ecos.fws.gov/docs/recovery_

plan/090116.pdf
64

Species Habitat Rationale Source 

Sea turtle, 

leatherback 

(Dermochelys 

coriacea)

Leatherbacks are able to take 

advantage of a wide variety 

of marine ecosystems 

(reviewed by Saba 2013; see 

NOAA large marine 

ecosystem website: 

http://www.lme.noaa.gov/). 

Within these ecosystems, 

various oceanic features such 

as water temperature, 

downwelling, Ekman 

upwelling, sea surface 

height, chlorophyll-a 

concentration, and mesoscale 

eddies affect the presence of 

leatherbacks (Bailey et al. 

2013; Benson et al. 2011). 

The physical characteristics 

observed within these marine 

ecosystems also affect the 

distribution and abundance 

of leatherback prey 

(reviewed by Saba 

2013). (NFMS, NOAA 2013, 

p. 20-22).

The proposed 

dicamba DGA uses 

are not expected to 

overlap with 

coastal waters.

NMFS, NOAA. 2013. Five Year 

Review. 

http://ecos.fws.gov/docs/recovery_

plan/090116.pdf

Shiner, 

Arkansas River 

(Notropis 

girardi)

Wilde et al. (2000) found no 

obvious selection for or 

avoidance of any particular 

habitat type (i.e., main 

channel, side channel, 

backwaters, and pools) by 

Arkansas River shiner. 

Arkansas River shiners did 

tend to select side channels 

and backwaters slightly more 

than expected based on the 

availability of these habitats 

(Wilde et al. 2000). 

Likewise, they appeared to 

make no obvious selection 

for, or avoidance of, any 

particular substrate type. 

Substrates (i.e., the river bed) 

in the Canadian River in 

New Mexico and Texas were 

predominantly sand, 

however, the Arkansas River 

shiner was observed to occur 

over silt slightly more than 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

US FWS. 2005. Federal Register 

Notice: Designation of Critical 

Habitat. 

http://ecos.fws.gov/docs/recovery_

plan/950830.pdf
65

Species Habitat Rationale Source 

expected based on the 

availability of this substrate 

(Wilde et al. 2000) ; 

preferred habitat for the 

Arkansas River shiner is the 

mainstem of larger plains 

rivers... historically inhabited 

the main channels of wide, 

shallow, sandy-bottomed 

rivers and larger streams of 

the Arkansas River basin 

(Gilbert 1980). Adults are 

uncommon in quiet pools or 

backwaters lacking 

streamflow, and almost never 

occurred in habitats having 

deep water and bottoms of 

mud or stone (Cross 1967) 

(US FWS 2005). 

Shiner, blue 

(Cyprinella 

caerulea)

The blue shiner primarily 

occupies second to fourth 

order, moderate gradient 

streams within the Ridge and 

Valley and Piedmont 

physiographic provinces of 

Alabama, Georgia, and 

Tennessee (Smith-Vaniz 

1968, Ramsey 1976, Krotzer 

1984, Ramsey and Pierson 

1986, Pierson and Krotzer 

1987, Mayden 1989, Pierson 

et al. 1989, Boschung 1992, 

Etnier and Starnes 1993, 

Dobson 1994). Most 

watersheds where it is found 

are predominately forested, 

and agriculture and urban 

development are minimal. 

For example in Alabama, 

land cover in the 

Choccolocco watershed is 66 

percent forest, 20 percent 

pasture, and 13 percent 

agriculture...It prefers a sand 

or sand and gravel substrate 

sometimes with cobble, low 

to moderate velocity current, 

and a depth of about 0.15 to 

1 meters (0.5 to 3 feet) 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

US FWS. 1995. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/950830.pdf
66

Species Habitat Rationale Source 

(Gilbert et al. 1979; Krotzer 

1984, Pierson and Krotzer 

1987, Dobson 1994) (US 

FWS 1995, p. 3-4)

Shiner, 

smalleye 

(Notropis 

buccula)

Occur in fairly shallow, 

flowing water, often less 

than 0.5 m deep with sandy 

substrates (US FWS 2014, p. 

45252)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 2014. Designation of 

Critical Habitat. 

http://www.gpo.gov/fdsys/pkg/FR2014-08-04/pdf/2014-17694.pdf

Snake, 

copperbelly 

water (Nerodia 

erythrogaster 

neglecta)

Copperbellies are generally 

affiliated with wetlands and 

prefer shallow wetlands, 

such as shrub-scrub wetlands 

dominated by

buttonbush (Cephalanthus 

occidentalis), emergent 

wetlands, or the margins of 

palustrine open water 

wetlands. Buttonbrush 

swamps are used as basking 

areas. Areas frequented by 

copperbellies generally have 

an open canopy, shallow 

water, and short dense 

vegetation. Uplands are also 

important. (US FWS, 2008, 

p. 17-18).

Critical Habitat has not been 

designated for the snake 

because of concerns related 

to illegal collection (US 

FWS, 2008. p. 20).

The proposed 

dicamba DGA uses 

are not expected to 

overlap with 

wetlands. 

USFWS. 2008. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/081223.pdf

Spectaclecase 

(mussel) 

(Cumberlandia 

monodonta)

The spectaclecase generally 

inhabits large rivers where it 

occurs in microhabitats 

sheltered from the main force 

of current. It occurs in a 

variety of substrates from 

mud and sand to gravel, 

cobble, and boulders in 

relatively shallow riffles and 

shoals with a slow to swift 

current. It is most often 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 2012. Federal Register 

Notice: Final Rule.

http://www.gpo.gov/fdsys/pkg/FR2012-03-13/pdf/2012-5603.pdf
67

Species Habitat Rationale Source 

found in firm mud between 

large rocks in quiet water 

very near the interface with 

swift currents (US FWS, 

2012, p 14916).

Spider, sprucefir moss 

(Microhexura 

montivaga)

Typical habitat appears to be 

associated with moist, welldrained moss mats growing 

on rocks and boulders in 

well-shaded situations in 

mature high-elevation 

conifer forests dominated by 

Fraser fir, Abiesfraseri, often 

with scattered red spruce, 

Picea rubens. (US FWS 

1998, p. iii)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with highelevation conifer 

forests. 

USFWS, 1998, Recovery Plan. 

http://www.gpo.gov/fdsys/pkg/FR2011-09-27/pdf/2011-24046.pdf

Southwestern 

willow 

flycatcher 

(Empidonax 

traillii extimus)

Breeding: Forested wetlands 

or scrub-shrub wetlandsdense riparian habitat of 

rivers, swamps, wetlands, 

lakes (USFWS 2002, p. iv).

Wintering: brushy savanna 

edges, second growth, 

shrubby clearings and 

pastures, woodlands near 

water (USFWS 2002, p. iv).

Recommend offfield status for row 

crop agriculture. 

According to the 

Critical Habitat 

designation 

document (USFWS 

2013) essential 

characteristics for 

southwestern will 

flycatcher habit 

include riparian 

areas for flowing 

stream that support 

expansive riparian 

vegetation areas. 

Riparian trees and 

understory species 

are viewed as 

essential elements 

of flycatcher 

habitat. Row crop 

soy and corn are 

monocultures of 

non-riparian 

vegetation and 

consequently not 

suitable habitat for 

this species.

USFWS 2002. Species specific 

recovery plan available on FWS 

website. 

http://ecos.fws.gov/docs/recovery_

plans/2002/020830c.pdf

USFWS. 2013. Designation of 

Southwestern Willow Flycatcher 

Critical Habitat: Final Rule. 

Federal Register Vol. 78 No.2.
68

Species Habitat Rationale Source 

Sperm whale 

(Physeter 

catodon 

(=macrocephal

us))

Ocean/ Water depth of 1968 

feet or more (NMFS 2012)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

NMFS. 2012. Sperm whales 

(Physeter catodon). National 

Marine Fisheries Service. 

Available online at: 

http://www.nmfs.noaa.gov/pr/speci

es/mammals/cetaceans/spermwhal

e.htm

Squirrel, 

Carolina 

northern flying 

(Glaucomys 

sabrinus 

coloratus)

Species composition of the 

occupied forest may vary in 

different locations, some 

combination of hardwoods 

and conifers (particularly 

spruce and fir) appears 

essential to support these 

animals...Food sources for 

the Carolina northern flying 

squirrel include fungi, 

lichens, staminate cones, 

insects, and other animal 

matter (US FWS 1990, p. 6-

7)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with 

hardwood and 

conifer forests. 

USFWS. 1990. Recovery Plan for 

Appalachian Northern Flying 

Squirrels. United States Fish and 

Wildlife Service. 

Stirrupshell 

(Quadrula 

stapes)

Habitat is the Tombigbee 

River, characterized by an 

increasing number of sand 

and gravel shoals and 

decreasing channel size in 

the upper portions (US FWS, 

1989). 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1989. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/891114e.pdf

Sturgeon, gulf 

(Acipenser 

oxyrinchus 

desotoi)

The Gulf sturgeon is an 

Anadromous fish which 

migrates from salt water into 

large coastal rivers to spawn

and spend the warm months. 

The majority of its life is 

spent in fresh water (US 

FWS, 1995). 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1995. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/950922.pdf

Sturgeon, pallid 

(Scaphirhynchu

s albus)

Habitat is the bottom in swift 

waters of large, turbid, freeflowing rivers, often over 

sand substrates, but other 

substrates include at least 

gravel and rock. Sloughs, 

chutes, and side channels 

that transition from 

floodplain to the main 

channels are apparently 

important as spawning, 

nursery, and feeding areas. 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 2014. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/Pallid%20Sturgeon%20Reco

very%20Plan%20First%20Revisio

n%20signed%20version%2001291

4_3.pdf

USFWS. 2007. Five Year Review. 

http://ecos.fws.gov/docs/five_year

_review/doc1059.pdf
69

Species Habitat Rationale Source 

Within the subject states, this 

habitat occurs in the 

Mississippi and Missouri 

rivers (US FWS, 1993, pp 6-

7). Within this habitat, they 

tend to select main channel 

habitats in the Mississippi 

River, and main channel 

habitats with islands or sand 

bars in the upper Missouri 

River (US FWS, 2007. p. 8). 

They do not typically occur 

in impounded areas due to 

lower flows and other 

hydrologic factors, nor where 

channel stabilization has 

reduced channel meandering 

and access to floodplain 

areas (US FWS, 2007, p. 38).

Tern, least 

interior pop. 

(Sterna 

antillarum)

Species is a piscivore, 

feeding in shallow waters of 

rivers, streams (USFWS, 

1990, p. 20). Beaches, sand 

pits, sandbars, islands and 

peninsulas are the principal 

breeding habitats of coastal 

areas and nesting can be 

close to water but is usually 

between the dune 

environment and the high 

tide line. Vegetation at 

coastal nesting areas is 

sparse, scattered and short. 

Riverine nesting areas are 

sparsely vegetated sand and 

gravel bars within a wide 

unobstructed river channel, 

or salt flats along lake 

shorelines. Nesting occurs 

along river banks (US FWS, 

1990, p. 20).

The proposed 

dicamba DGA uses 

are not expected to 

overlap with 

riparian areas, 

including coastal 

areas. 

USFWS. 1990. Recovery Plan.

http://ecos.fws.gov/docs/recovery_

plan/900919a.pdf

Texas blind 

salamander 

(Typhlomolge 

rathbuni)

Aquatic, subterranean 

(caves) (USFWS 1996)

The proposed 

dicamba DGA uses 

are not expected to 

overlap with rivers, 

streams, creeks, or 

other water bodies.

USFWS. 1996. San Marcos and 

Comal Springs and associated 

aquatic ecosystems (Revised) 

recovery plan. United States Fish 

and Wildlife Service. Available 

online at: 
70

Species Habitat Rationale Source 

http://ecos.fws.gov/docs/recovery_

plan/960214.pdf

Warbler, 

Kirtland’s 

(Setophaga 

kirtlandii)

Forests (US FWS 1985, p. 8)

During breeding, Kirtland’s 

warblers are located in 

Michigan. Its wintering 

grounds are located in the 

Bahamas, where it spends 8 

months of the year 

(September-April). (US FWS 

1985)

In migration, the bird travels 

a fairly direct route between 

its nesting and wintering 

ranges, entering and leaving 

the continent at the coast of 

North and South Carolina 

(USFWS 1985, p. 5).

With one or few exceptions, 

all nests have been found on 

Grayling sand soil (USFWS 

1985, p. 7).

The proposed 

dicamba DGA uses 

are not expected to 

overlap with 

forests.

USFWS. 1985 Kirtland's Warbler 

Recovery Plan, Updated.

http://ecos.fws.gov/docs/recovery_

plan/850930.pdf

Whale, finback 

(Balaenoptera 

physalus)

Fin whales are found in deep, 

offshore waters of all major 

oceans, primarily in 

temperate to polar latitudes, 

and less commonly in the 

tropics. They occur yearround in a wide range of 

latitudes and longitudes, but 

the density of individuals in 

any one area changes 

seasonally.

The proposed 

dicamba DGA uses 

are not expected to 

overlap with 

coastal waters.

http://www.nmfs.noaa.gov/pr/speci

es/mammals/cetaceans/finwhale.ht

m

Whale, 

humpback 

(Megaptera 

novaeangliae)

During migration, 

humpbacks stay near the 

surface of the ocean.

While feeding and calving, 

humpbacks prefer shallow 

waters. During calving, 

humpbacks are usually found 

The proposed 

dicamba DGA uses 

are not expected to 

overlap with 

coastal waters.

http://www.nmfs.noaa.gov/pr/speci

es/mammals/cetaceans/humpback

whale.htm
71

Species Habitat Rationale Source 

in the warmest waters 

available at that latitude. 

Calving grounds are 

commonly near offshore reef 

systems, islands, or 

continental shores.

Humpback feeding grounds 

are in cold, productive 

coastal waters. 

Wartyback, 

white 

(pearlymussel) 

(Plethobasus 

cicatricosus)

The white wartyback has 

undergone a substantial 

range reduction and is 

considered to be possibly 

extinct. It was historically 

distributed in the Wabash, 

Ohio, Kanawha, 

Cumberland, Holston, and 

Tennessee Rivers of the 

Ohio, Cumberland, and 

Tennessee River systems; 

however, no live specimens 

have been recovered from 

these drainages since the 

early 1900s). The white 

wartyback may still exist in a 

short reach of the Tennessee 

River below Pickwick Dam. 

No living populations have 

been found in numerous 

surveys conducted in the 

Tennessee River since the 

1960s; however, fresh dead 

specimens were collected in 

1979 and 1982 below 

Pickwick Dam near 

Savannah, Tennessee. If this 

species still exists, the 

viability of remaining 

populations is extremely 

threatened 

The white wartyback is a 

riffle species that is typically 

found in large rivers in 

gravel substrates.

The proposed 

dicamba DGA uses 

are not expected to 

overlap with 

coastal waters.

USFWS, 1984, Recovery Plan 

White Warty-backed Pearlymussel

http://ecos.fws.gov/docs/recovery_

plan/060313h.pdf

http://ecos.fws.gov/docs/life_histor

ies/F00M.html
72

Species Habitat Rationale Source 

Woodpecker, 

red-cockaded 

Entire (Picoides 

borealis)

Habitat: Forest, Savannah 

(open pine woodlands and 

savannahs with large old 

pines) (US FWS 2003, p. x)

Habitat size (home range): 

116 – 357 acres (US FWS 

2003, p. 49)

Proposed dicamba 

DGA uses are not 

expected to overlap 

with forest or 

savannah. 

USFWS. 2003. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/030320_2.pdf

Wood stork 

(Mycteria 

americana)

Freshwater and estuarine 

Wetlands. (US FWS 1986, p. 

iii).

Wood storks breed in FL, 

GA and SC. They migrate 

south in winter (US FWS 

1986, p. 2). 

Require a mosaic of wetlands 

with varying climatological 

and seasonal conditions 

around colonies and within 

the wintering habitat in the 

coastal plain of the Southeast 

U.S. (US FWS 2006, p. 12).

The proposed 

dicamba DGA uses 

are not expected to 

overlap with 

wetlands.

USFWS. 1986. Recovery Plan.

http://ecos.fws.gov/docs/recovery_

plan/970127.pdf

USFWS. 2006. Five year Review. 

http://ecos.fws.gov/docs/five_year

_review/doc1115.pdf

Noonday globe 

(Patera clarki 

nantahala)

Found mainly on the 

southeast side of the 

Nantahala River Gorge. 

Area is strikingly 

different than the 

surrounding area, very 

steep, with a mix of 

various hardwood trees 

and hemlock, and has a 

rich herbaceous 

undergrowth. The area 

is interrupted frequently 

by small streams, 

waterfalls, seeps, 

springs, and often 

shaded. The forest floor 

has a thick humus layer 

with much exposed 

rock, where the snail is 

most abundant on and 

around moist rock 

outcrops, but also found 

in thick leaf litter and 

humus layers around 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

forests. 

Noonday Globe Patera 

(=Mesodon) clarki nantahala 5-

Year Review: Summary and 

Evaluation, Page 4

Available at:

http://ecos.fws.gov/docs/five_year

_review/doc4295.pdf
73

the base of ferns and 

underneath 

rhododendron and dog 

hobbe, and other moist 

habitats. Moisture is 

key. 

Phantom 

springsnail 

(Pyrgulopsis 

texana)

The Phantom 

springsnail occurs only 

in the four remaining 

desert spring 

outflow channels 

associated with the 

San Solomon Spring 

system (San 

Solomon, Phantom, 

Giffin, and East 

Sandia springs). 

Habitat of the species is 

found on 

both soft and firm 

substrates on the 

margins of spring 

outflows (Taylor 1987, 

p. 41). They are also 

commonly found 

attached to plants, 

particularly in dense 

stands of submerged 

vegetation 

(Chara sp.). Field and 

laboratory experiments 

have suggested 

Phantom springsnails 

prefer substrates harder 

and larger in 

size (Bradstreet 2011, p. 

91). 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2013. Determination of 

Endangered Species Status for Six 

West Texas Aquatic Invertebrates: 

Final Rule. Page 41236.

Available at:

http://www.gpo.gov/fdsys/pkg/FR2013-07-09/pdf/2013-16222.pdf

Phantom 

tryonia (Tryonia 

cheatumi)

The Phantom tryonia 

occurs only in 

the four remaining 

desert spring outflow 

channels associated 

with the San 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2013. Determination of 

Endangered Species Status for Six 

West Texas Aquatic Invertebrates: 

Final Rule. Page 41236-41237.

Available at:

http://www.gpo.gov/fdsys/pkg/FR2013-07-09/pdf/2013-16222.pdf
74

Solomon Spring system 

(San Solomon, 

Phantom, Giffin, and 

East Sandia 

springs) (Taylor 1987, 

p. 40; Allan 2011, 

p. 1; Lang 2011, entire). 

The species is found on 

both soft and firm 

substrates on the 

margins of spring 

outflows (Taylor 1987, 

p. 41), and they are also 

commonly found 

attached to plants, 

particularly in dense 

stands of submerged 

vegetation (Chara sp.). 

Armored snail 

(Pyrgulopsis 

(=Marstonia) 

pachyta)

The armored snail

is currently only known 

from Limestone and 

Piney Creeks, 

Limestone County, 

Alabama, and appears 

to be most abundant in 

submerged root masses 

and bryophytes (nonvascular land plants, 

e.g. mosses) along the 

creek edges, but also 

may occur on rocks and 

leafy/woody debris, and 

on other aquatic 

macrophytes 

(aquatic plants) 

(Garner 2004a, 

Haggerty and Garner 

2007, 2008).

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2010. Armored Snail 

(Marstonia pachyta) 5-Year 

Review. Page 2.

Available at:

http://ecos.fws.gov/docs/five_year

_review/doc3288.pdf

Pecos assiminea 

snail (Assiminea 

pecos)

The Pecos assiminea 

requires saturated, 

moist soil at stream or 

spring- run margins and 

is found in wet mud or 

beneath mats of 

vegetation, usually 

within 1 inch (in) (2 to 

3 centimeters 

(cm)) of flowing water. 

Spring complexes that 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2011. Designation of 

Critical Habitat for Roswell 

Springsnail, Koster's Springsnail, 

Noel's Amphipod, and Pecos 

Assiminea; Final Rule. Page 

33039. Available at:

http://www.gpo.gov/fdsys/pkg/FR2011-06-07/pdf/2011-13227.pdf
75

contain flowing water 

create saturated soils 

that provide the specific 

habitat needed for 

population growth, 

sheltering, and normal 

behavior of the species. 

Although this snail 

seldom occurs 

immersed in water, the 

species cannot 

withstand permanent 

drying of springs or 

spring complexes. 

Consequently, wetland 

plant species are 

required to provide leaf 

litter (dead leaf 

material), shade, and 

appropriate 

microhabitat. Plant 

species such as 

Scirpus americanus 

(American threesquare), Eleocharis 

spp. (spike rush), 

Distichlis spicata 

(inland saltgrass), and 

Juncus spp. (rushes) 

provide the appropriate 

cover and shelter 

required by Pecos 

assiminea (NMDGF 

2005, p. 

13). 

Diamond Y 

Spring snail 

(Pseudotryonia

adamantina)

Habitat of the species is 

primarily soft 

substrates on the 

margins of small 

springs, seeps, and 

marshes in shallow 

flowing water 

associated with 

emergent bulrush 

(Scirpus americanus) 

and saltgrass (Distichlis 

spicata) 

(Taylor 1987, p. 38; 

Echelle et al. 2001, 

p.5). 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2013. Determination of 

Endangered Species Status for Six 

West Texas Aquatic Invertebrates: 

Final Rule. Page 41237.

Available at:

http://www.gpo.gov/fdsys/pkg/FR2013-07-09/pdf/2013-16222.pdf
76

Tulotoma snail 

(Tulotoma 

magnifica)

Tulotoma occur in cool, 

well-oxygenated, clean, 

free-flowing streams, 

including rivers and the 

lower portions of the 

rivers’ larger tributaries 

(Herschler et al. 1990, 

p. 822). This species is 

generally found in 

shoals (a shallow place 

in a body of water) and 

riffles (a rocky shoal 

lying just below the 

surface of the water) 

with moderate to strong 

currents. Although this 

species is typically 

associated with shoals 

and riffles, it inhabits 

rivers that rise and 

fall, and tulotoma have 

been collected at 

depths more than 5 

meters (m) (15 feet 

(ft)) (Hartfield 1991, p. 

7). The species is 

strongly associated with 

boulder, cobble, and 

bedrock stream bottoms 

and is generally found 

clinging tightly to the 

underside of large rocks 

or between cracks in 

bedrock (Christman et 

al. 1996, p. 28). 

Historical habitats 

included large coastal 

plain river, large highgradient rivers, and 

multiple upland 

tributary streams. 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2011. Final 

Reclassification of the Tulotoma 

Snail From Endangered to 

Threatened. Page 31867.

Available at:

http://www.gpo.gov/fdsys/pkg/FR2011-06-02/pdf/2011-13687.pdf

Gonzales 

springsnail 

(Tryonia 

circumstriata)

Habitat of the species is 

primarily soft substrates 

on the margins of small 

springs, seeps, and 

marshes in shallow 

flowing water 

associated with 

emergent bulrush and 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2013. Determination of 

Endangered Species Status for Six 

West Texas Aquatic Invertebrates: 

Final Rule. Page 41238.

Available at:

http://www.gpo.gov/fdsys/pkg/FR2013-07-09/pdf/2013-16222.pdf
77

saltgrass (Taylor 1987, 

p. 38; Echelle et al. 

2001, p. 5). 

Lacy elimia 

(snail) (Elimia 

crenatella)

Lacy elimia typically 

inhabit highly 

oxygenated waters on 

rock shoals and gravel 

bars. 

Currently, the lacy 

elimia is only known to 

survive in three Coosa 

River tributaries--

Cheaha, Emauhee, and 

Weewoka Creeks, 

Talladega County, 

Alabama (Bogan and 

Pierson, 1993a). 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers or other water 

bodies.

USFWS 2005. Final Recovery 

Plan for Six Mobile Basin Aquatic 

Snails. Page 8.

Available at:

http://ecos.fws.gov/docs/recovery_

plan/051202.pdf

Rough 

hornsnail 

(Pleurocera 

foremani)

Rough hornsnails are 

primarily found on 

gravel, cobble, bedrock, 

and mud in moderate 

currents. They have 

been collected at depths 

of 1 m (3.3 ft) to 3 m 

(9.8 ft) (Hartfield 2004, 

p. 132). The species 

appears to tolerate lowto- moderate levels of 

silt deposition (Sides 

2005, p. 127). 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2010. Determination of 

Endangered Status for the Georgia 

Pigtoe Mussel, Interrupted 

Rocksnail, and Rough Hornsnail 

and Designation of Critical 

Habitat; Final Rule. Page 67514.

Available at:

http://www.gpo.gov/fdsys/pkg/FR2010-11-02/pdf/2010-

27417.pdf#page=2

Cylindrical 

lioplax (snail) 

(Lioplax 

cyclostomaform

is)

The cylindrical lioplax 

is currently

known only from 

approximately 24 

kilometers (km) 

(15 miles (mi)) of the 

Cahaba River above the 

Fall Line in Shelby and 

Bibb counties, Alabama 

(Bogan and Pierson, 

1993b). 

Habitat for the 

cylindrical lioplax is 

unusual for the genus, 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2005. Final Recovery 

Plan for Six Mobile Basin Aquatic 

Snails. Page 4.

Available at:

http://ecos.fws.gov/docs/recovery_

plan/051202.pdf
78

as well as for other 

genera of viviparid 

snails. It lives in 

isolated mud deposits 

found under large rocks 

in the rapid flowing 

sections of stream and 

river shoals. 

Flat pebblesnail 

(Lepyrium 

showalteri)

The flat pebblesnail is 

currently known from

One site on the Little 

Cahaba River, Bibb 

County, and from

a single shoal series on 

the Cahaba River above 

the Fall Line, Shelby 

County, Alabama 

(Bogan and Pierson, 

1993b). 

The flat pebblesnail is 

found attached to clean, 

smooth stones in rapid 

currents of river shoals.

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2005. Final Recovery 

Plan for Six Mobile Basin Aquatic 

Snails. Page 6.

Available at:

http://ecos.fws.gov/docs/recovery_

plan/051202.pdf

Painted 

rocksnail 

(Leptoxis 

taeniata)

The painted rocksnail is 

currently known from 

the lower reaches of 

three Coosa River 

tributaries--

Choccolocco Creek, 

Talladega County; 

Buxahatchee Creek, 

Shelby County (Bogan 

and Pierson, 1993a); 

and Ohatchee Creek, 

Calhoun County, 

Alabama (Pierson in 

litt, 1993). 

Painted rocksnails are 

found attached to 

cobble, gravel, or other 

hard substrates in the 

strong currents of riffles 

(a shallow area in a 

streambed that causes 

ripples in the water) and 

shoals. Adult rocksnails 

move very little, and 

females probably glue 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2005. Final Recovery 

Plan for Six Mobile Basin Aquatic 

Snails. Page 10.

Available at:

http://ecos.fws.gov/docs/recovery_

plan/051202.pdf
79

their eggs to stones in 

the same habitat 

(Goodrich, 1922). 

Plicate 

rocksnail 

(Leptoxis 

plicata)

Plicate rocksnails 

inhabit shallow gravel 

and cobble shoals in 

flowing waters. 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2005. Final Recovery 

Plan for Six Mobile Basin Aquatic 

Snails. Page 14.

Available at:

http://ecos.fws.gov/docs/recovery_

plan/051202.pdf

Round rocksnail 

(Leptoxis 

ampla)

The round rocksnail is 

currently known from a 

shoal series in the 

Cahaba River, Bibb and 

Shelby counties, 

Alabama, and from the 

lower reach of the Little 

Cahaba River, and the 

lower reaches of Shade 

and Six-mile creeks in 

Bibb County, Alabama 

(Bogan and Pierson, 

1993b). 

Painted rocksnails are 

found attached to 

cobble, gravel, or other 

hard substrates in the 

strong currents of riffles 

(a shallow area in a 

streambed that causes 

ripples in the water) and 

shoals. Adult rocksnails 

move very little, and 

females probably glue 

their eggs to stones in 

the same habitat 

(Goodrich, 1922). 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2005. Final Recovery 

Plan for Six Mobile Basin Aquatic 

Snails. Page 12.

Available at:

http://ecos.fws.gov/docs/recovery_

plan/051202.pdf

Slender 

campeloma 

(Campeloma 

decampi)

Campeloma decampi is 

typically found 

burrowing in soft 

sediment (sand and/or 

mud) or detritus. It does 

not appear abundant at 

any site, and the spotty 

distribution appears 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

wetlands.

USFWS 2000. Endangered Status 

for the Armored Snail and Slender 

Campeloma; Final Rule. Page 

10034.

Available at:

http://ecos.fws.gov/docs/federal_re

gister/fr3525.pdf
80

consistent with other 

Campeloma 

species

Interrupted 

(=Georgia) 

Rocksnail 

(Leptoxis 

foremani)

Rocksnails live in 

shoals, riffles, and reefs 

(bedrock outcrops) of 

small to large rivers. 

Their habitats are 

generally subject to 

moderate currents 

during low flows and 

strong currents during 

high flows. These snails 

live attached to 

bedrocks, boulders, 

cobbles, and gravel and 

tend to move little, 

except in response to 

changes in water level. 

They lay their adhesive 

eggs within the same 

habitat (Johnson 2004, 

p.116). 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2010. Determination of 

Endangered Status for the Georgia 

Pigtoe Mussel, Interrupted 

Rocksnail, and Rough Hornsnail 

and Designation of Critical 

Habitat; Final Rule. Page 67513.

Available at:

http://www.gpo.gov/fdsys/pkg/FR2010-11-02/pdf/2010-

27417.pdf#page=2

Hungerford's 

crawling water 

Beetle 

(Brychius 

hungerfordi)

River/stream(moderate 

to fast flow), depth of 

few inches to few feet, 

inorganic substrate. 

(USFWS 2009, p 5)

1st, 2nd and 3rd order 

perennial streams 

(USFWS 2006, p 22)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

US FWS, Hungerford's crawling 

water Beetle (Brychius 

hungerfordi) 5 Year Review, 2009

Available at:

http://ecos.fws.gov/docs/five_year

_review/doc2584.pdf

US FWS, Hungerford's crawling 

water Beetle (Brychius 

hungerfordi) Recovery Plan, 2006

Available at:

http://ecos.fws.gov/docs/recovery_

plan/060928a.pdf

Coffin Cave 

mold beetle 

(Batrisodes 

texanus)

Troglobitic habitat 

includes caves and 

mesocavernous voids in 

karst limestone (a 

terrain characterized by 

landforms and 

subsurface features, 

such as sinkholes

The proposed dicamba 

DGA uses are not 

expected to overlap with 

caves.

US FWS-Coffin Cave Mold Beetle 

(Batrisodes texanus) 5-Year 

Review: Summary and Evaluation

Page 2

Available at:

http://ecos.fws.gov/docs/five_year

_review/doc3017.pdf
81

Kretschmarr 

Cave mold 

beetle 

(Texamaurops 

reddelli)

Their habitat includes 

caves and 

mesocavernous voids in 

karst limestone (a 

terrain characterized by 

landforms and 

subsurface features, 

such as sinkholes and 

caves, which are 

produced by solution of 

bedrock)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

caves.

US FWS-Tooth Cave Spider 

(Neoleptoneta 

myopica),Kretschmarr Cave Mold 

Beetle (Texamaurops reddelli), 

and Tooth Cave Pseudoscorpion 

(Tartarocreagris texana) 5-Year 

Review: Summary and Evaluation

Page 2

Available at:

http://ecos.fws.gov/docs/five_year

_review/doc3018.pdf 

Tooth Cave 

ground beetle 

(Rhadine 

persephone)

They spend their entire 

lives underground and 

are endemic to karst 

formations (caves, 

sinkholes, and other 

subterranean voids).

The proposed dicamba 

DGA uses are not 

expected to overlap with 

caves.

US FWS-Recovery Plan for 

Endangered Karst Invertebrates in 

Travis and Williamson Counties, 

Texas

Page III

Available at:

http://ecos.fws.gov/docs/recovery_

plan/940825.pdf

Comal Springs 

riffle beetle 

(Heterelmis 

comalensis)

High quality unpolluted 

groundwater and spring 

outflows that have low 

levels of salinity and 

turbidity. High-quality 

discharge water from 

springs and adjacent 

subterranean areas also 

help sustain habitat 

components, such as 

riparian vegetation that 

are essential to the 

Peck’s cave amphipod, 

Comal Springs dryopid 

beetle, and Comal 

Springs riffle beetle. 

The two beetle species 

are thought to require 

water with adequate 

levels of dissolved 

oxygen for respiration 

(Brown 1987, p. 260; 

Arsuffi 1993, p. 18).

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2006. Designation of 

Critical Habitat for the Peck's Cave 

Amphipod, Comal Springs 

Dryopid Beetle, and Comal 

Springs Riffle Beetle; Proposed 

Rule. Page 40592.

Available at:

http://www.gpo.gov/fdsys/search/c

itation.result.FR.action?federalReg

ister.volume=2006&federalRegiste

r.page=40588&publication=FR

Comal Springs 

dryopid beetle 

(Stygoparnus 

comalensis)

High quality unpolluted 

groundwater and spring 

outflows that have low 

levels of salinity and 

turbidity. High-quality 

discharge water from 

springs and adjacent 

subterranean areas also 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2006. Designation of 

Critical Habitat for the Peck's Cave 

Amphipod, Comal Springs 

Dryopid Beetle, and Comal 

Springs Riffle Beetle; Proposed 

Rule. Page 40592.

Available at:
82

help sustain habitat 

components, such as 

riparian vegetation that 

are essential to the 

Peck’s cave amphipod, 

Comal Springs dryopid 

beetle, and Comal 

Springs riffle beetle. 

The two beetle species 

are thought to require 

water with adequate 

levels of dissolved 

oxygen for respiration 

(Brown 1987, p. 260; 

Arsuffi 1993, p. 18).

http://www.gpo.gov/fdsys/search/c

itation.result.FR.action?federalReg

ister.volume=2006&federalRegiste

r.page=40588&publication=FR

Saint Francis' 

satyr butterfly 

(Neonympha 

mitchellii 

francisci)

The habitat occupied by 

this satyr consists 

primarily of wide wet 

meadows dominated by 

a high diversity of 

sedges (Carex spp.) and 

other wetland 

graminoids

The proposed dicamba 

DGA uses are not 

expected to overlap with 

wet meadows.

US FWS-Recovery Plan for Saint 

Francis' Satyr Butterfly

Page 2

Available at:

http://ecos.fws.gov/docs/recovery_

plan/960423.pdf 

[Unnamed] 

ground beetle 

(Rhadine 

infernalis)

Caves and 

mesocavernous voids in 

karst limestone 

(landforms and 

subsurface features, for 

example, sinkholes and 

caves, produced by 

dissolution of bedrock)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

caves.

U.S. Fish and Wildlife Service. 

2011. Bexar County Karst 

Invertebrates Recovery Plan. 

U.S. Fish and Wildlife Service, 

Albuquerque, NM. Page 

vi (comments - 7). Available at:

http://ecos.fws.gov/docs/recovery_

plan/Final%202001%20Bexar%20

Co%20Invertebrates%20Rec%20P

lan_1.pdf

Helotes mold 

beetle 

(Batrisodes 

venyivi)

Caves and 

mesocavernous voids in 

karst limestone 

(landforms and 

subsurface features, for 

example, sinkholes and 

caves, produced by 

dissolution of bedrock)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

caves.

U.S. Fish and Wildlife Service. 

2011. Bexar County Karst 

Invertebrates Recovery Plan. 

U.S. Fish and Wildlife Service, 

Albuquerque, NM. Page 

vi (comments - 7). Available at:

http://ecos.fws.gov/docs/recovery_

plan/Final%202001%20Bexar%20

Co%20Invertebrates%20Rec%20P

lan_1.pdf

[Unnamed] 

ground beetle 

(Rhadine exilis)

Caves and 

mesocavernous voids in 

karst limestone 

(landforms and 

subsurface features, for 

example, sinkholes and 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

caves.

U.S. Fish and Wildlife Service. 

2011. Bexar County Karst 

Invertebrates Recovery Plan. 

U.S. Fish and Wildlife Service, 

Albuquerque, NM. Page 

vi (comments - 7). Available at:
83

caves, produced by 

dissolution of bedrock)

http://ecos.fws.gov/docs/recovery_

plan/Final%202001%20Bexar%20

Co%20Invertebrates%20Rec%20P

lan_1.pdf

Bee Creek Cave 

harvestman 

(Texella 

reddelli)

Bee Creek Cave 

Harvestman inhabit 

limestone caves. They 

are only able to survive 

in caves that maintain 

stable temperatures and 

humidity (close to 

100%). They have been 

found in caves both on 

the north and south side 

of the Colorado river. 

They live in 'karst' type 

of terrain , which is 

formed by "dissolution 

of calcium carbonate 

from limestone bedrock 

by mildly acidic 

groundwater.

The proposed dicamba 

DGA uses are not 

expected to overlap with 

caves.

USFWS-Recovery Plan for 

Endangered Karst Invertebrates in 

Travis and Williamson Counties, 

Texas U.S. Fish and Wildlife 

Service

Page III

Available at:

http://ecos.fws.gov/docs/recovery_

plan/940825.pdf

Bone Cave 

harvestman 

(Texella reyesi)

Caves and 

mesocavernous voids in 

karst limestone

The proposed dicamba 

DGA uses are not 

expected to overlap with 

caves.

USFWS Bone Cave Harvestman 

5-Year Review

Page 2

Available at:

http://ecos.fws.gov/docs/five_year

_review/doc3016.pdf

Tooth Cave 

pseudoscorpion 

(Tartarocreagri

s texana)

Their habitat includes 

caves and 

mesocavernous voids in 

karst limestone (a 

terrain characterized by 

landformsand 

subsurface features, 

such as sinkholes and 

caves, which are 

produced by solution of 

bedrock). There are 

currently four caves that 

support the Tooth Cave 

pseudoscorpion 

(Tartarocreagris 

texana).

The proposed dicamba 

DGA uses are not 

expected to overlap with 

caves.

US FWS-Tooth Cave Spider 

(Neoleptoneta myopica), 

Kretschmarr Cave Mold Beetle 

(Texamaurops reddelli), and Tooth 

Cave Pseudoscorpion 

(Tartarocreagris texana) 5-Year 

Review: Summary and Evaluation 

Page 2

Available at:

http://ecos.fws.gov/docs/five_year

_review/doc3018.pdf
84

Tooth Cave 

Spider 

(Leptoneta 

myopica)

Their habitat includes 

caves and 

mesocavernous voids in 

karst limestone (a 

terrain characterized by 

landforms and 

subsurface features, 

such as sinkholes and 

caves, which are 

produced by solution of 

bedrock). There are 

currently six caves 

known to contain the

Tooth Cave spider 

(Neoleptoneta 

myopica).

The proposed dicamba 

DGA uses are not 

expected to overlap with 

caves.

US FWS Tooth Cave Spider, 

Kretschmarr Cave Mold Beetle, 

and Tooth Cave Pseudoscorpion 5-

Year Review

Page 2

Available at:

http://ecos.fws.gov/docs/five_year

_review/doc3018.pdf

Cokendolpher 

Cave 

Harvestman 

(Texella 

cokendolpheri)

Caves and 

mesocavernous voids in 

karst limestone 

(landforms and 

subsurface features, for 

example, sinkholes and 

caves, produced by 

dissolution of bedrock)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

caves.

U.S. Fish and Wildlife Service. 

2011. Bexar County Karst 

Invertebrates Recovery Plan. 

U.S. Fish and Wildlife Service, 

Albuquerque, NM.

Page vi

Available at:

http://ecos.fws.gov/docs/recovery_

plan/Final%202001%20Bexar%20

Co%20Invertebrates%20Rec%20P

lan_1.pdf

Government 

Canyon Bat 

Cave Spider 

(Neoleptoneta 

microps)

Caves and 

mesocavernous voids in 

karst limestone 

(landforms and 

subsurface features, for 

example, sinkholes and 

caves, produced by 

dissolution of bedrock)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

caves.

U.S. Fish and Wildlife Service. 

2011. Bexar County Karst

Invertebrates Recovery Plan. 

U.S. Fish and Wildlife Service, 

Albuquerque, NM.

Page vi

Available at:

http://ecos.fws.gov/docs/recovery_

plan/Final%202001%20Bexar%20

Co%20Invertebrates%20Rec%20P

lan_1.pdf

Madla's Cave 

Meshweaver 

(Cicurina 

madla)

Caves and 

mesocavernous voids in 

karst limestone 

(landforms and 

subsurface features, for 

example, sinkholes and 

caves, produced by 

dissolution of bedrock)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

caves.

U.S. Fish and Wildlife Service. 

2011. Bexar County Karst 

Invertebrates Recovery Plan. 

U.S. Fish and Wildlife Service, 

Albuquerque, NM.

Page vi

Available at:

http://ecos.fws.gov/docs/recovery_

plan/Final%202001%20Bexar%20

Co%20Invertebrates%20Rec%20P

lan_1.pdf
85

Robber Baron 

Cave 

Meshweaver 

(Cicurina 

baronia)

Caves and 

mesocavernous voids in 

karst limestone 

(landforms and 

subsurface features, for 

example, sinkholes and 

caves, produced by 

dissolution of bedrock)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

caves.

U.S. Fish and Wildlife Service. 

2011. Bexar County Karst 

Invertebrates Recovery Plan. 

U.S. Fish and Wildlife Service, 

Albuquerque, NM.

Page vi

Available at:

http://ecos.fws.gov/docs/recovery_

plan/Final%202001%20Bexar%20

Co%20Invertebrates%20Rec%20P

lan_1.pdf

Government 

Canyon Bat 

Cave 

Meshweaver 

(Cicurina 

vespera)

Caves and 

mesocavernous voids in 

karst limestone 

(landforms and 

subsurface features, for 

example, sinkholes and 

caves, produced by 

dissolution of bedrock)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

caves.

U.S. Fish and Wildlife Service. 

2011. Bexar County Karst 

Invertebrates Recovery Plan. 

U.S. Fish and Wildlife Service, 

Albuquerque, NM.

Page vi

Available at:

http://ecos.fws.gov/docs/recovery_

plan/Final%202001%20Bexar%20

Co%20Invertebrates%20Rec%20P

lan_1.pdf

Braken Bat 

Cave 

Meshweaver 

(Cicurina venii)

Caves and 

mesocavernous voids in 

karst limestone 

(landforms and 

subsurface features, for 

example, sinkholes and 

caves, produced by 

dissolution of bedrock)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

caves.

U.S. Fish and Wildlife Service. 

2011. Bexar County Karst 

Invertebrates Recovery Plan. 

U.S. Fish and Wildlife Service, 

Albuquerque, NM.

Page vi

Available at:

http://ecos.fws.gov/docs/recovery_

plan/Final%202001%20Bexar%20

Co%20Invertebrates%20Rec%20P

lan_1.pdf

Peck's cave 

amphipod 

(Stygobromus 

(=Stygonectes) 

pecki)

High quality unpolluted 

groundwater and spring 

outflows that have low 

levels of salinity and 

turbidity. High-quality 

discharge water from 

springs and adjacent 

subterranean areas also 

help sustain habitat 

components, such as 

riparian vegetation that 

are essential to the 

Peck’s cave amphipod, 

Comal Springs dryopid 

beetle, and Comal 

Springs riffle beetle. 

The two beetle species 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2006. Designation of 

Critical Habitat for the Peck's Cave 

Amphipod, Comal Springs 

Dryopid Beetle, and Comal 

Springs Riffle Beetle; Proposed 

Rule. Page 40592.

Available at:

http://www.gpo.gov/fdsys/search/c

itation.result.FR.action?federalReg

ister.volume=2006&federalRegiste

r.page=40588&publication=FR
86

are thought to require 

water with adequate 

levels of dissolved 

oxygen for respiration 

(Brown 1987, p. 260; 

Arsuffi 1993, p. 18).

Alabama cave 

shrimp 

(Palaemonias 

alabamae)

Silt-bottomed cave 

pools (USFWS 1997)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

US FWS, Alabama Cave Shrimp 

(Palaemonias_alabamae) 5 year 

review, 2006. Available at:

http://ecos.fws.gov/docs/five_year

_review/doc747.pdf

US FWS, Alabama Cave Shrimp 

(Palaemonias_alabamae) recovery 

plan, 1997. Available at:

http://ecos.fws.gov/docs/recovery_

plan/970904.pdf

Kentucky cave 

shrimp 

(Palaemonias 

ganteri)

Very specific habitat 

requirements- large, 

base level passages of 

caves characterized by 

slow flow, abundant 

organic matter, and 

coarse to fine grain 

sand and coarse silt 

sediments.

The proposed dicamba 

DGA uses are not 

expected to overlap with 

caves.

US FWS, Kentucky Cave shrimp 

completed 5-year review, 2010. 

Page 5.

Available at:

http://ecos.fws.gov/docs/five_year

_review/doc3203.pdf

Diminutive 

Amphipod 

(Gammarus 

hyalleloides)

Amphipods in the 

Gammarus pecos 

species complex occur 

only in desert 

spring outflow channels 

on substrates, 

often within interstitial 

spaces on and 

underneath rocks and 

within gravels 

(Lang et al. 2003, p. 49) 

and are most commonly 

found in microhabitats 

with flowing water. 

They are also 

commonly found in 

dense stands of 

submerged vegetation 

(Cole 1976, p. 80). 

Because of 

their affinity for 

constant water 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2013. Determination of 

Endangered Species Status for Six 

West Texas Aquatic Invertebrates: 

Final Rule. Page 41238.

Available at:

http://www.gpo.gov/fdsys/pkg/FR2013-07-09/pdf/2013-16222.pdf
87

temperatures, they are 

most common in 

the immediate spring 

outflow channels, 

usually only a few 

hundred meters

downstream of spring 

outlets. 

Alabama 

pearlshell 

(Margaritifera 

marrianae)

The Alabama pearlshell 

typically inhabits small 

headwater streams with 

mixed sand and gravel 

substrates, occasionally 

in sandy mud, with 

slow to moderate 

current.

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2012. Determination of 

Endangered Species Status for the 

Alabama Pearlshell, Round 

Ebonyshell, Southern Kidneyshell, 

and Choctaw Bean, and 

Threatened Species Status for the 

Tapered Pigtoe, Narrow Pigtoe, 

Southern Sandshell, and Fuzzy 

Pigtoe, and Designation of Critical 

Habitat: Final rule. Page 61667

Altamaha 

Spinymussel 

(Elliptio 

spinosa)

This spinymussel is 

considered a ‘‘big 

river’’ species; is 

associated with stable, 

coarse-to-fine sandy 

sediments of sandbars, 

sloughs, and midchannel islands; and 

appears to be restricted 

to swiftly flowing water 

(Sickel 1980, p. 12).

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2011. Endangered Status 

for the Altamaha Spinymussel and 

Designation of Critical Habitat; 

Final Rule. Page 62928

Carolina 

heelsplitter 

(Lasmigona 

decorata)

It has been recorded 

from a variety of 

substrates (including 

mud, clay, sand, gravel, 

and cobble/boulder/ 

bedrock) without 

significant silt 

accumulations, along 

stable, well-shaded 

stream banks (Keferl

and Shelly 1988, Keferl

1991). However, 

individuals have also 

been found near the 

center of the stream 

channel in relatively 

silt-free substrates 

comprised primarily of 

a mixture of sand, 

gravel, and cobble, with 

scattered areas of 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

http://ecos.fws.gov/docs/life_histor

ies/F02L.html
88

exposed boulders/ 

bedrock (J. Fridell 

personal observation, 

1995).

Chipola 

slabshell 

(Elliptio 

chipolaensis)

The Chipola slabshell 

inhabits silty sand 

substrates of large 

creeks and the main 

channel of the Chipola 

River in slow to 

moderate current 

(Williams and Butler 

1994). Specimens are 

generally found in 

sloping bank habitats. 

Nearly 70 percent of the 

specimens found during 

the status survey were 

associated with a sandy 

substrate (Brim Box 

and Williams 2000).

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2003. Recovery Plan for 

7 mussels. Page 43.

http://ecos.fws.gov/docs/recovery_

plan/030930.pdf

Choctaw bean 

(Villosa 

choctawensis)

It is found in medium 

creeks to medium rivers 

in stable substrates of 

silty sand to sandy clay 

with moderate current.

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2012. Determination of 

Endangered Species Status for the 

Alabama Pearlshell, Round 

Ebonyshell, Southern Kidneyshell, 

and Choctaw Bean, and 

Threatened Species Status for the 

Tapered Pigtoe, Narrow Pigtoe, 

Southern Sandshell, and Fuzzy 

Pigtoe, and Designation of Critical 

Habitat: Final rule. Page 61669

Cracking 

pearlymussel 

(Hemistena 

lata)

The cracking 

pearlymussel inhabits 

streams of moderate 

size on gravel riffles 

where it is often deeply 

buried in the substrate 

(Bogan and Parmalee 

1983). Substrate 

preferences include 

sand, gravel, and cobble 

in high velocity areas 

and mud and sand in 

slower moving waters 

(Gordon and Layzer 

1989).

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

http://ecos.fws.gov/docs/life_histor

ies/F01X.html
89

Cumberland 

elktoe 

(Alasmidonta 

atropurpurea)

This species inhabits 

medium-sized rivers 

and may extend into 

headwater streams 

where it is often the 

only mussel present 

(Gordon and Layzer 

1989, Gordon 1991). 

Gordon and Layzer 

(1989) reported that the 

species appears to be 

most abundant in flats, 

which were described 

by Gordon (1991) as 

shallow pool areas

lacking the bottom 

contour development of 

typical pools, with sand 

and scattered 

cobble/boulder 

material, relatively 

shallow depths, and 

slow (almost 

imperceptible) currents. 

They also report the 

species from swifter 

currents and in areas 

with mud, sand, and 

gravel substrates.

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2004. Cumberland and 

Tennessee River Mussels (5 spp.)

Page 18.

Dark pigtoe 

(Pleurobema 

furvum)

Sand/gravel/cobble 

shoals and rapids in 

small rivers and large 

streams.

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2000. Recovery Plan for 

the Mobile River Basin (15 

species). Page 53

Dwarf 

wedgemussel 

(Alasmidonta 

heterodon)

The dwarf wedge 

mussel lives on muddy 

sand, sand, and gravel 

bottoms in creeks and 

rivers of varying sizes, 

in areas of slow to 

moderate current and 

little silt deposition.

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 1993. Dwarf Wedge 

Mussel recovery plan. Page 3.

Fat three-ridge 

(mussel) 

(Amblema 

neislerii)

The fat threeridge 

inhabits the main 

channel of small to 

large rivers in slow to 

moderate current. 

Substrate used by this 

mussel varies from 

gravel to cobble to a 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2003. Recovery Plan for 

7 mussels. Page 42.

http://ecos.fws.gov/docs/recovery_

plan/030930.pdf
90

mixture of sand and 

sandy mud (Williams 

and Butler 1994). Brim 

Box and Williams 

(2000) found 60 percent 

of the specimens were 

located in a sandy silt 

substrate.

Flat pigtoe 

(Pleurobema 

marshalli)

The flat pigtoe, like 

other Tombigbee River 

system mussels, 

inhabits moderate to 

large rivers with 

moderate to swift 

current. Its preferred 

habitat is riffle-run or 

shoal areas with stable 

substrates ranging from 

sandy gravel to gravelcobble (Stanbery 1976, 

1980, 1983). Unionids 

collected from the 

Tombigbee River 

system have been 

collected in water up to 

0.7 meters deep 

(USFWS 1987).

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

http://ecos.fws.gov/docs/life_histor

ies/F013.html

Fuzzy pigtoe 

(Pleurobema 

strodeanum)

The fuzzy pigtoe is 

found in medium creeks 

to medium rivers in 

stable substrates of sand 

and silty sand with slow 

to moderate current. 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2012. Determination of 

Endangered Species Status for the 

Alabama Pearlshell, Round 

Ebonyshell, Southern Kidneyshell, 

and Choctaw Bean, and 

Threatened Species Status for the 

Tapered Pigtoe, Narrow Pigtoe, 

Southern Sandshell, and Fuzzy 

Pigtoe, and Designation of Critical 

Habitat: Final rule. Page 61673

Gulf 

moccasinshell 

(Medionidus 

penicillatus)

The Gulf moccasinshell 

inhabits the channels of 

small to medium-sized 

creeks to large rivers 

with sand and gravel or 

silty sand substrates in 

slow to moderate 

currents (Williams and 

Butler 1994; Garner, 

pers. comm. 2003). 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2003. Recovery Plan for 

7 mussels. Page 43.

http://ecos.fws.gov/docs/recovery_

plan/030930.pdf
91

Heavy pigtoe 

(Pleurobema 

taitianum)

The heavy pigtoe, like 

other Tombigbee River 

system mussels, 

inhabits moderate to 

large rivers with 

moderate to swift 

current. Its preferred 

habitat is riffle-run or 

shoal areas with stable 

substrates ranging from 

sandy gravel to gravelcobble (Stanbery 1976, 

1980, 1983). Unionids

collected from the 

Tombigbee River 

system have been 

collected in water up to 

0.7 meters deep 

(USFWS 1987).

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

http://ecos.fws.gov/docs/life_histor

ies/F014.html

James 

spinymussel 

(Pleurobema 

collina)

This species lives in 

stream sites that vary in 

width from 10-75 feet 

and depth of 1/2 to 3 

feet. It requires a slow 

to moderate water 

current with clean sand 

and cobble bottom 

sediments. The James 

spinymussel is limited 

to areas of unpolluted 

water, and may be more 

susceptible to 

competition from exotic 

clam species when its 

habitat is disturbed 

(Clark and Neves 1984, 

USFWS 1990).

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

http://ecos.fws.gov/docs/life_histor

ies/F025.html

Narrow pigtoe 

(Fusconaia 

escambia)

It is found in medium 

creeks to medium 

rivers, in stable 

substrates of sand, sand 

and gravel, or silty 

sand, with slow to 

moderate current. 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2012. Determination of 

Endangered Species Status for the 

Alabama Pearlshell, Round 

Ebonyshell, Southern Kidneyshell, 

and Choctaw Bean, and 

Threatened Species Status for the 

Tapered Pigtoe, Narrow Pigtoe, 

Southern Sandshell, and Fuzzy 

Pigtoe, and Designation of Critical 

Habitat: Final rule. Page 61671
92

Ochlockonee 

moccasinshell 

(Medionidus 

simpsonianus)

The Ochlockonee

moccasinshell inhabits 

large creeks and the 

Ochlockonee River 

main stem in areas with 

current. Typical 

substrates are sand with 

some gravel (Williams 

and Butler 1994).

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2003. Recovery Plan for 

7 mussels. Page 43.

http://ecos.fws.gov/docs/recovery_

plan/030930.pdf

Oval pigtoe 

(Pleurobema 

pyriforme)

The oval pigtoe occurs 

in small to mediumsized creeks to small 

rivers where it inhabits 

silty sand to sand and 

gravel substrates, 

usually in slow to 

moderate current 

(Williams and Butler

1994; Garner, pers. 

comm. 2003). Stream 

channels appear to offer 

the best habitat for this 

species.

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2003. Recovery Plan for 

7 mussels. Page 43.

http://ecos.fws.gov/docs/recovery_

plan/030930.pdf

Purple 

bankclimber 

(mussel) 

(Elliptoideus 

sloatianus)

The purple bankclimber 

inhabits small to large 

river channels in slow 

to moderate current 

over sand or sand 

mixed with mud or 

gravel substrates 

(Williams and Butler 

1994). 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2003. Recovery Plan for 

7 mussels. Page 43.

http://ecos.fws.gov/docs/recovery_

plan/030930.pdf

Ring pink 

(mussel) 

(Obovaria 

retusa)

The ring pink inhabits 

gravel and sandy 

substrates in large rivers 

of the Ohio River basin

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS, 1991. Ring Pink Mussel 

Recovery Plan. Page 4. 

http://ecos.fws.gov/docs/recovery_

plan/910325.pdf

Round 

Ebonyshell 

(Fusconaia

rotulata)

It occurs in small to 

medium rivers, 

typically in stable 

substrates of sand, 

small gravel, or sandy 

mud in slow to 

moderate current. 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2012. Determination of 

Endangered Species Status for the 

Alabama Pearlshell, Round 

Ebonyshell, Southern Kidneyshell, 

and Choctaw Bean, and 

Threatened Species Status for the 

Tapered Pigtoe, Narrow Pigtoe, 

Southern Sandshell, and Fuzzy 

Pigtoe, and Designation of Critical 

Habitat: Final rule. Page 61668
93

Shinyrayed 

pocketbook 

(Lampsilis 

subangulata)

The shinyrayed 

pocketbook inhabits 

small to medium-sized 

creeks, to rivers in clean 

or silty sand substrates 

in slow to moderate 

current (Williams and 

Butler 1994; Garner, 

pers. comm. 2003). 

Specimens are often 

found in the interface of 

stream channel and 

sloping bank habitats, 

where sediment particle 

size and current 

strength are transitional. 

Clench and Turner 

(1956) noted it 

preferred small creeks 

and spring-fed rivers. 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2003. Recovery Plan for 

7 mussels. Page 42.

http://ecos.fws.gov/docs/recovery_

plan/030930.pdf

Southern 

acornshell 

(Epioblasma 

othcaloogensis)

The southern acornshell 

was historically 

restricted to shoals in 

small rivers to

Small streams above the 

Fall Line. It was found 

on stable 

sand/gravel/cobble 

substrate in moderate to 

swift currents.

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2000. Recovery Plan for 

the Mobile River Basin (15 

species). Page 57

Southern 

kidneyshell 

(Ptychobranchu

s jonesi)

It is typically found in 

medium creeks to small 

rivers in firm sand 

substrates with slow to 

moderate current 

(Williams et al. 2008, 

pp. 625).

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2012. Determination of 

Endangered Species Status for the 

Alabama Pearlshell, Round 

Ebonyshell, Southern Kidneyshell, 

and Choctaw Bean, and 

Threatened Species Status for the 

Tapered Pigtoe, Narrow Pigtoe, 

Southern Sandshell, and Fuzzy 

Pigtoe, and Designation of Critical 

Habitat: Final rule. Page 61668

Southern 

sandshell 

(Hamiota 

(=Lampsilis) 

australis)

The southern sandshell 

is typically found in 

small creeks and rivers 

in stable substrates of 

sand or mixtures of 

sand and fine gravel, 

with slow to moderate 

current. 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2012. Determination of 

Endangered Species Status for the 

Alabama Pearlshell, Round 

Ebonyshell, Southern Kidneyshell, 

and Choctaw Bean, and 

Threatened Species Status for the 

Tapered Pigtoe, Narrow Pigtoe, 

Southern Sandshell, and Fuzzy 

Pigtoe, and Designation of Critical 

Habitat: Final rule. Page 61672
94

Tapered pigtoe 

(Fusconaia 

burkei)

The tapered pigtoe is 

found in medium creeks 

to medium rivers in 

stable substrates of 

sand, small gravel, or 

sandy mud, with slow 

to moderate current 

(Williams et al. 2008, p. 

296). 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2012. Determination of 

Endangered Species Status for the 

Alabama Pearlshell, Round 

Ebonyshell, Southern Kidneyshell, 

and Choctaw Bean, and 

Threatened Species Status for the 

Tapered Pigtoe, Narrow Pigtoe, 

Southern Sandshell, and Fuzzy 

Pigtoe, and Designation of Critical 

Habitat: Final rule. Page 61670

Tar River 

spinymussel 

(Elliptio 

steinstansana)

The preferred habitat of 

the Tar spinymussel 

appears to be relatively 

fast-flowing, 

well-oxygenated water, 

in sites with a substrate 

comprised of relatively 

silt-free, uncompacted 

gravel and coarse sand 

(USFWS 1992).

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

http://ecos.fws.gov/docs/life_histor

ies/F015.html

Upland 

combshell 

(Epioblasma 

metastriata)

Restricted to shoals in 

rivers and large streams 

above the Fall Line. It 

was found on stable

sand/gravel/cobble

substrate in moderate to 

swift currents.

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2000. Recovery Plan for 

the Mobile River Basin (15 

species). Page 61

Yellow blossom 

(pearlymussel) 

(Epioblasma 

florentina 

florentina)

Riverine and typically 

found in streams which 

are shallow with sandygravel substrate with 

rapid currents 

(Stansbery, 1971)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 1985. Recovery plan for 

three mussels. Page 20.

http://ecos.fws.gov/docs/recovery_

plan/850125.pdf

Alabama 

cavefish 

(Speoplatyrhinu

s poulsoni)

The only known 

locality at which the 

Alabama cavefish 

occurs is Key Cave in 

Lauderdale county, 

Alabama. Low 

temperature and 

periodic flooding are 

characteristic of the 

aquatic habitat in caves 

(USFWS 1990)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 1990. Alabama cavefish 

recovery plan. Page 2. Available 

online at:

http://ecos.fws.gov/docs/recovery_

plan/901025.pdf
95

Alabama 

sturgeon 

(Scaphirhynchu

s suttkusi)

Very little is known of 

the habitat requirements 

of the Alabama 

Sturgeon. Based on 

capture data, it inhabits 

the main channel of 

large coastal plain 

rivers of the Mobile 

River Basin. Most 

specimens have been 

taken in moderate to 

swift current at depths 

of 6 to 14 m, over sand, 

gravel or mud bottom 

(Williams and Clemmer 

1991). (USFWS 2013)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2013. Recovery Plan for 

the Alabama Sturgeon 

(Scaphirhynchus suttkusi). Page 

13.

Big Bend 

gambusia 

(Gambusia 

gaigei)

The Big Bend gambusia 

is restricted to small, 

desert spring habitats. 

The spring ponds at Rio 

Grande Village that 

harbor the fish are clear 

warm water, 

stenothermal (constant 

temperature) springs. 

Hubbs (2001, pp. 315-

316) documented the 

average outflow 

temperatures of Spring 

4 and Spring 1 as 34.9 

oC (95oF) and 33.1oC 

(92oF), respectively, 

with very low 

variability. The Big 

Bend gambusia is often 

found associated with 

dense stands of Chara 

spp. (submerged plant) 

and emergent 

vegetation in the refuge 

ponds (Hubbs et al. 

2002, p. 82).

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2012. Big Bend gambusia 

- 5 year review. Page 8.

Cahaba shiner 

(Notropis 

cahabae)

The habitat of the 

Cahaba shiner appears 

to be large shoal areas 

in the main channel of 

the Cahaba river 

(Howell et al. 1982). 

The species is found in 

the quieter waters, less 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 1992. Cahaba shiner 

(Notropis cahabae) Recovery plan. 

Pages 1-3. Available at:

http://ecos.fws.gov/docs/recovery_

plan/920423.pdf
96

than 1.6 feet (0.5 

meters) deep, just 

below swift riffle areas 

(Howell et al. 1982). 

The Cahaba shiner 

seems to prefer sandy 

patches in gravel beds 

or downstream of larger 

rocks and boulders. The

species is generally

found in relatively 

clear, well oxygenated 

water. It probably

requires a river with 

sufficient small 

crustaceans, insect 

larvae, and algae for 

food, similar to its close 

relatives (Gilbert and 

Burgess 1980). 

(USFWS 1992)

Cape Fear 

shiner (Notropis 

mekistocholas)

The Cape Fear shiner is 

generally associated 

with gravel, cobble, and 

boulder substrate, and it 

has been observed 

inhabiting slow pools, 

riffles, and slow runs 

often associated with 

water willow (Justicia) 

beds (Palmer and 

Braswell, North 

Carolina State Museum 

of Natural History, 

personal 

communication, 1986; 

Pottern and Huish 1985, 

1986; Snelson 1971).

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 1988. Cape Fear shiner 

Recovery Plan. Page 1.

Available at:

http://ecos.fws.gov/docs/recovery_

plan/060313.pdf

Cherokee darter 

(Etheostoma 

scotti)

Cherokee darters 

inhabit small to medium 

size warm-water creeks 

of moderate gradient 

with predominantly 

rocky bottoms. They 

are usually found in 

shallow water sections 

of reduced currents 

typically in areas above 

and below riffles and at 

the ecotones of riffles 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 1994. ETWP; 

Determination of Threatened 

Status for the Cherokee Darter and 

Endangered Status for the Etowah 

Darter. Page 65506.
97

and backwaters. 

Moreover, this species 

as associated with large 

gravel, cobble, and 

small boulder 

substrates, and is 

uncommonly, or rarely 

found over bedrock, 

fine gravel, or sand. It is 

most abundant in 

stream sections with 

relatively clear water 

and clean substrates 

(little Silt deposition). 

(USFWS 1994)

The Cherokee darter is 

endemic to the Etowah 

River system in north 

Georgia where it is 

primarily restricted to 

streams draining the 

Piedmont physiographic 

province, and to a lesser 

extent, the Blue Ridge 

physiographic province. 

(USFWS 1994)

Clear Creek 

gambusia 

(Gambusia 

heterochir)

This species is 

restricted to the Clear 

Creek headspring pool 

that is characterized as 

clear, stenothermal, low 

pH (6.1 - 6.5) water 

with abundant aquatic 

vegetation composed 

mostly of an endemic, 

undescribed morph of 

Ceratophyllum sp.

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 1982. Recovery Plan for 

Clear Creek Gambusia. Pages 2-3.

Life Histories: Clear Creek 

Gambusia (Gambusia heterochir). 

http://ecos.fws.gov/docs/life_histor

ies/E005.html

Comanche 

Springs pupfish 

(Cyprinodon 

elegans)

The present habitat of 

the species consists 

mostly of a system of 

earthen and concrete 

irrigation canals. The 

water from Phantom 

Lake Spring is diverted 

into agricultural fields 

or sometimes flows 

down Phantom Lake 

Canal to merge with the 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 1981. Recovery Plan for 

the Comanche Springs Pupfish. 

Page 2.

Available at:

http://ecos.fws.gov/docs/recovery_

plan/051221a.pdf
98

flow from San Solomon 

Spring.

Devils River 

minnow 

(Dionda 

diaboli)

(1) Streams 

characterized by: 

a. Areas with slow to 

moderate water 

velocities between 10 

and 40 cm/second 

(4 and 16 in/second) in 

shallow to moderate 

water depths between 

approximately 10 cm (4 

in) and 1.5 m (4.9 ft), 

near vegetative 

structure, such as 

emergent or submerged 

vegetation or stream 

bank riparian vegetation 

that 

overhangs into the 

water column; 

b. Gravel and cobble 

substrates ranging in 

diameter between 2 and 

10 cm (0.8 and 4 in) 

with low or moderate 

amounts of fine 

sediment (less than 65 

percent stream bottom 

coverage) and low or 

moderate amounts of 

substrate 

embeddedness; and 

c. Pool, riffle, run, and 

backwater components 

free of artificial 

instream structures that 

would prevent 

movement of fish 

upstream or 

downstream. 

(2) High-quality water 

provided by permanent, 

natural flows from 

groundwater springs 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2008. Designation of 

Critical Habitat for the Devils 

River Minnow; Final rule. 73 FR 

46988 47026. Page 47001.

Available at:

http://www.gpo.gov/fdsys/pkg/FR2008-08-12/pdf/E8-

17985.pdf#page=1
99

and seeps characterized 

by: 

a. Temperature ranging 

between 17°C and 

29°C; 

b. Dissolved oxygen 

levels greater 

than 5.0 mg/l; 

c. Neutral pH ranging 

between 7.0 and 

8.2; 

d. Conductivity less 

than 0.7 mS/cm 

and salinity less than 1 

ppt; 

e. Ammonia levels less 

than 0.4 mg/l; and 

f. No or minimal 

pollutant levels for 

copper, arsenic, 

mercury, and cadmium; 

human and animal 

waste products; 

pesticides; fertilizers; 

suspended sediments; 

and petroleum 

compounds and 

gasoline or diesel fuels. 

(3) Abundant aquatic 

food base consisting of 

algae; attached to 

stream substrates; and 

other microorganisms 

associated with stream 

substrates. 

(4) Aquatic stream 

habitat either 

devoid of nonnative 

aquatic species 

(including fish, plants, 

and invertebrates) or in 

which such nonnative 

aquatic species are at 

levels that allow for 

healthy populations of 

Devils River minnows. 

(5) Areas within stream 

courses that may be 

periodically dewatered 

for short time periods, 
100

during seasonal 

droughts, but otherwise 

serve as connective 

corridors between 

occupied or seasonally 

occupied areas through 

which the species 

moves when the area is 

wetted. (USFWS 2008)

Etowah darter 

(Etheostoma 

etowahae)

The Etowah darter 

inhabits warm and cool, 

medium and large 

creeks or small rivers 

that are moderate or 

high gradient with 

rocky bottoms and 

relatively shallow 

riffles and large gravel, 

cobble, and small 

boulder substrates. 

(USFWS 1994)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

1994. USFWS ETWP; 

Determination of Threatened 

Status for the Cherokee Darter and 

Endangered Status for the Etowah 

Darter. Page 65506. 

Available at:

http://ecos.fws.gov/docs/federal_re

gister/fr2753.pdf

Fountain darter 

(Etheostoma 

fonticola)

The fountain darter 

requires: 1) undisturbed 

stream floor habitats 

(including runs, riffles, 

and pools), 2) a mix of 

submergent vegetation 

(algae, mosses, and 

vascular plants) in part 

for cover, 3) clear and 

clean water, 4) constant 

water temperatures 

within the natural and 

normal river gradients, 

and 5) most 

importantly, adequate 

springflows. In general, 

E. fonticola prefers 

vegetated stream-floor 

habitats with constant 

water temperature. 

Higher densities of the 

fish are found in mats 

of the filamentous green 

algae (Rhizoclonium 

sp.) and the moss 

Riccia. It is 

occasionally found in 

areas lacking 

vegetation. Fountain 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks,

or other water bodies.

USFWS 1996. San Marcos and 

Comal springs and associated 

aquatic ecosystems (revised) 

recovery plan. Page 33. Available 

at:

http://ecos.fws.gov/docs/recovery_

plan/960214.pdf
101

darters have also been 

observed among leaf 

litter in the Comal 

River. (USFWS 1996)

Goldline darter 

(Percina 

aurolineata)

Prefers a moderate to 

swift current and water 

depths greater than 2 

feet (Howell et al. 

1982). It is found over 

sand or gravel substrate 

interspersed among 

cobble and small 

boulders. (USFWS 

1992)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

1992. USFWS ETWP; Threatened 

Status for Two Fish, the Goldline 

Darter (Percina aurolineata) and 

Blue Shiner (Cyprinella caerulea). 

Page 14786. 

http://ecos.fws.gov/docs/federal_re

gister/fr2036.pdf

Leon Springs 

pupfish 

(Cyprinodon 

bovinus)

The Leon Springs 

pupfish inhabits highly 

saline habitat preferring 

quiet waters near the 

edge of shallow pools 

with a minimal growth 

of vegetation. (USFWS 

1980)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

1980. USFWS ETWP; Listing of 

Leon Springs pupfish as 

endangered with critical habitat. 

Page 14786. 

http://ecos.fws.gov/docs/federal_re

gister/fr457.pdf

Palezone shiner 

(Notropis 

albizonatus)

The palezone shiner 

occurs in flowing pools 

and runs of upland 

streams that have 

permanent flow, clear 

water, and substrates 

composed of bedrock, 

cobble, pebble, and 

gravel mixed with clean 

sand (USFWS 1997). In 

May 1990, Warren et 

al. (1994) collected the 

species in the PRR from 

pools (60-75 cm depth) 

over fine to coarse 

gravel mixed with sand. 

In June 1990, Warren et 

al. (1994) observed the 

species in shallow (30-

45 cm, 1.2-1.8 in) runs 

and pools of the Little 

South Fork that were 

underlain by fractured 

bedrock and scattered 

gravel patches. In 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2014. Palezone shiner 

(Notropis albizonatus) 5-year 

review: summary and evaluation. 

US Fish and Wildlife Service 

Southest Region Kentucky 

Ecological Services Field Office 

John C. Watts Federal Building 

330 West Broadway, Room 265 

Frankfort Kentucky, 40601. Page 

8.

http://ecos.fws.gov/docs/five_year

_review/doc4374.pdf
102

August 1990, they 

collected individuals in 

the Little South Fork 

from pools and runs 

with current velocities 

ranging from 0.6-4.5 

cm/sec (0.02-0.15 

feet/sec) and mean 

depth of 59 cm (2.3 in). 

Substrates varied from 

sand mixed with fine 

and coarse gravel to 

bedrock. Shepard et al. 

(1997) reported the 

species from pools and 

runs of the PRR that 

had substrates 

composed of a mixture 

of cobble, gravel, and 

sand. Water depths 

ranged from 30.5-76.2 

cm (12-30 in). (USFWS 

2014)

Pecos gambusia 

(Gambusia 

nobilis)

Gambusia nobilis

occurs abundantly in 

springheads and spring 

runs. Moderately 

abundant populations 

are also known from 

areas with little spring 

influence, but with 

abundant overhead 

cover, sedge covered 

marshes, and gypsum 

sinkholes. G. nobilis

has been observed to 

occur from the surface 

to depths of three meter. 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS ECOS Life Histories for 

the Pecos gambusia (Gambusia 

nobilis)

http://ecos.fws.gov/docs/life_histor

ies/E00V.html

Pygmy Sculpin 

(Cottus paulus 

(=pygmaeus))

Gravel and sand 

substrate. Habitat also 

contains large rocks 

where the spring boils 

occur. 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

Life Histories: Pygmy sculpin 

(Cottus paulus (=pygmaeus)).

http://ecos.fws.gov/docs/life_histor

ies/E01L.html

Relict darter 

(Etheostoma 

chienense)

Adults are concentrated 

in headwaters of 

streams in slow flowing 

pools (0.2-0.6 m/sec), 

usually over gravel 

mixed with sand and 

under or near cover 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

2013. US Fish and Wildlife 

Service Southeast Region, Relict 

darter (Etheostoma chienense) 

Five Year Review Summary and 

Evaluation, Page 8.
103

such as fallen tree 

branches, undercut 

banks, or overhanging 

riparian vegetation. 

(USFWS 2013)

https://ecos.fws.gov/docs/five_yea

r_review/doc4178.pdf

Rush Darter 

(Etheostoma 

phytophilum)

Habitats tend to be 

shallow, clear, and cool, 

with moderate current 

and substrates 

composed of a 

combination of sand 

with silt, muck, gravel 

or bedrock. (USFWS 

2012)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

Fish and Wildlife Service 

Department of the Interior, 2012, 

Endangered and Threatened 

Wildlife and Plants; Designation 

of Critical Habitat for the 

Cumberland darter, Rush darter, 

Yellowcheek darter, Chucky 

madtom, and Laurel dace, Volume 

77 No. 200, Page 63605

http://www.gpo.gov/fdsys/pkg/FR2012-10-16/pdf/2012-24468.pdf

San Marcos 

gambusia 

(Gambusia 

georgei)

The San Marcos 

gambusia apparently 

prefers quiet waters 

adjacent to sections of 

moving water, but 

seemingly of greatest 

importance, thermally 

constant waters. G. 

georgei is found mostly 

over muddy substrates 

but generally not silted 

habitats, and shade 

from over-hanging 

vegetation or bridge 

structures is a factor 

common to all sites 

along the upper San 

Marcos River where 

apparently suitable 

habitats for this species 

occur (Hubbs and 

Peden 1969, Edwards 

et. al. 1980).

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 1996. San Marcos and 

Comal springs and associated 

aquatic ecosystems (revised) 

recovery plan. Page 29. Available 

at:

http://ecos.fws.gov/docs/recovery_

plan/960214.pdf

Sharpnose 

Shiner 

(Notropis

oxyrhynchus)

Sharpnose shiners occur 

in fairly 

shallow, flowing water, 

often less than 

0.5 m (1.6 ft) deep with 

sandy substrates...

minimum estimated 

reach length 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS 2014. Designation of 

Critical Habitat for Sharpnose 

Shiner and Smalleye Shiner; Final 

Rule. Page 45250.
104

requirements for similar 

species and current 

modeling efforts for this 

species indicate an 

unobstructed reach 

length of greater than 

275 km (171 mi) is 

likely required to 

complete the species’ 

life history. 

Shortnose 

sturgeon 

(Acipenser 

brevirostrum)

Shortnose sturgeon are 

found in rivers, 

estuaries, and the sea, 

but populations are 

confined mostly to

natal rivers and 

estuaries. The species 

appears to be estuarine 

anadromous in the 

southern part of its

range, but in some 

northern rivers it is 

"freshwater 

amphidromous", i.e., 

adults spawn in 

freshwater but regularly 

enter saltwater habitats 

during their life (Kieffer 

and Kynard 1993). 

Adults in southern 

rivers forage at the 

interface of fresh tidal 

water and saline 

estuaries and enter the 

upper reaches of rivers 

to spawn in early spring 

(Savannah River: Hall 

et al. 1991; Altamaha 

River: Heidt and Gilbert 

1979; Flouronoy et al. 

1992, Rogers and 

Weber 1995a; 

Ogeechee River: Weber 

1996). 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

NMFS 1998. Final Recovery Plan 

for the Shortnose Sturgeon 

(Acipenser brevirostrum). Page 25. 

Available at:

http://ecos.fws.gov/docs/recovery_

plan/sturgeon_shortnose_1.pdf
105

Smalltooth 

sawfish (Pristis 

pectinata)

Generally inhabit the 

shallow coastal waters 

of bays, banks, estuaries 

and river mouths, 

particularly shallow 

mud banks and 

mangrove habitats. 

Larger animals can be 

found in the same 

habitat, but are also 

found offshore at depths 

up to least 122 meters.

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

National Marine Fisheries Service, 

2009, Smalltooth sawfish 

Recovery Plan. Page v.

http://ecos.fws.gov/docs/recovery_

plan/smalltoothsawfish.pdf

Sunfish, spring 

pygmy 

(Elassoma 

alabamae)

Clear to slightly stained 

spring water, occurring 

within spring heads 

(where cool water 

emerges from the 

ground), spring pools 

(water pool at spring 

head), spring runs 

(stream or channel 

downstream of spring 

pool), and associated 

spring-fed wetlands... 

occupying depths from 

13 to 102 cm (in water 

column)... prefers 

patches of dense

filamentous submergent 

vegetation

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

Endangered and Threatened 

Wildlife and Plants; Threatened 

Species Status for Spring Pygmy 

Sunfish, Federal Register, 2013, 

78(191): 60766-60783. Page 

60768.

http://www.gpo.gov/fdsys/pkg/FR2013-10-02/pdf/2013-23726.pdf

Vermilion 

darter 

(Etheostoma 

chermocki)

Small to medium-sized 

clear streams, with 

gravel riffles and 

moderate currents 

(Kuehne and Barbour, 

1983; Etnier and 

Starnes, 1993). 

Boschung et al. (1992) 

described the stream 

habitat for vermilion 

darters as 3 to 20 m 

wide, 0.01 to more than 

0.5 m in depth, with 

pools of moderate 

current alternating with 

riffles of moderately 

swift current, and low 

water turbidity. Blanco 

and Mayden (1999) 

found this species 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

Daniel J Drennen and the 

Vermilion Darter Recovery Team / 

US Fish and Wildlife Service 

Department of Interior, 2007, 

Recovery Plan Vermilion Darter, 

Page 11

http://ecos.fws.gov/docs/recovery_

plan/070802.pdf
106

primarily in areas 

dominated by fine 

gravel with some coarse 

gravel or cobble. This 

species is absent in 

habitats with only a 

bedrock bottom, but has 

been found on bedrock 

with sand and 

gravel...This species is 

generally not found in 

deeper pool habitats.

Waccamaw 

silverside 

(Menidia 

extensa)

The species is usually 

found in schools near 

the surface. It forages 

in areas of shallow, 

open water over a clean, 

dark sand substrate with 

no vegetation and 

spawn in open-water 

areas near the shoreline.

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS Life histories document. 

http://ecos.fws.gov/docs/life_histor

ies/E01P.html

Watercress 

darter 

(Etheostoma 

nuchale)

Prefer deeper, slow 

moving backwater areas 

of springs that are 

choked with aquatic 

vegetation such as 

watercress 

(Nasturtium), and algae 

(Chara and Spirogyra).

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS Life Histories Watercress 

darter (Etheostoma nuchale)

http://ecos.fws.gov/docs/life_histor

ies/E00U.html

Species Habitat Rationale Source 

Plants

Avens, 

spreading 

(Geum 

radiatum)

This species grows in 

full sun on the shallow 

acidic soils of highelevation cliffs, rocky 

outcrops, steep slopes, 

and on gravelly talus 

(US FWS, 1993).

The proposed dicamba 

DGA uses are not 

expected to overlap with 

high-elevation cliffs, 

rocky outcrops, steep 

slopes or gravelly talus. 

USFWS. 1993. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/930428.pdf

Bluet, Roan 

Mountain 

(Hedyotis 

purpurea var. 

montana)

This species grows in 

shallow soils and 

crevices of cliffs and 

outcrops and on thin 

rocky soils of grassy 

balds (US FWS, 1996). 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

cliffs and outcrops. 

USFWS. 1996. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/960513.pdf
107

Species Habitat Rationale Source 

Chaffseed, 

American 

(Schwalbea 

americana)

Habitats described as 

pine flatwoods, firemaintained savannas, 

ecotonal areas between 

peaty wetlands and 

xeric sandy soils, and 

other open grass-sedge 

systems (US FWS, 

1995).

The proposed dicamba 

DGA uses are not 

expected to overlap with 

pine flatwoods, firemaintained savannas, 

wetland or sedge 

dominated systems. 

USFWS. 1995. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/950929c.pdf

Clover, running 

buffalo 

(Trifolium 

stoloniferum)

Running buffalo clover 

occurs in mesic habitats 

of partial to filtered 

sunlight, where there is 

a prolonged pattern of 

moderate periodic 

disturbance, such as 

mowing, trampling, or 

grazing. It is most 

often found in regions 

underlain with 

limestone or other 

calcareous bedrock. 

Specific habitats 

include mesic 

woodlands, savannahs, 

floodplains, stream 

banks, sandbars, grazed 

woodlots, mowed paths 

(e.g. cemeteries, parks), 

old logging roads, jeep 

trails, ATV trails, skid 

trails, mowed wildlife 

openings within mature 

forest, and steep 

ravines. It has been 

suggested that the 

original habitat may 

have been open woods 

or savannah, and bison 

herbivory on associated 

species may have kept 

the habitats open (US 

FWS, 2007, p. 12.).

The proposed dicamba 

DGA uses are not 

expected to overlap with 

mesic habitats where the 

clover is expected to be 

found. 

USFWS. 2007. Recovery Plan.

http://ecos.fws.gov/docs/recovery_

plan/070627.pdf
108

Species Habitat Rationale Source 

Daisy, Lakeside 

(Hymenoxys 

herbacea)

Although historical 

habitats include 

outcrops of dolomite or 

limestone bedrock, dry, 

gravelly prairies on 

terraces or hills 

associated with major 

river systems, rocky 

shores, sandy fields and 

alvars, the Lakeside 

daisy in the U. S. is 

now restricted to dry, 

thin-soiled, degraded 

prairies in which 

limestone or dolomite 

bedrock is at or near the 

surface. Habitats are 

alkaline, seasonally wet 

in spring and fall, and 

are moderately to 

extremely droughty in 

summer. Typically, 

habitats have little 

topographic relief, are 

relatively open at the 

ground surface, and 

vegetation density and 

diversity are relatively 

low. Within these 

habitats, lakeside daisy 

occurs in open patches 

of ground, occupies the 

dry to mesic portions of 

the soil moisture 

continuum and has a 

highly aggregated 

distribution. This 

species is either absent 

or infrequently found in 

shaded or densely 

vegetated areas (US 

FWS, 1990, pp. 20-21).

The proposed dicamba 

DGA uses are not 

expected to overlap with 

quarries and dry prairies.

USFWS. 1990. Recovery Plan.

http://ecos.fws.gov/docs/recovery_

plan/900919b.pdf

Fern, American 

hart's-tongue 

(Asplenium 

scolopendrium 

var. 

americanum)

Early successional 

habitats Northern 

populations occur in 

forests of secondary 

growth where canopy 

openings are abundant. 

New York populations 

The proposed dicamba 

DGA uses are not 

expected to overlap early 

successional forests, 

conifer forests or 

bryophyte beds where 

the species is found.

http://ecos.fws.gov/docs/recovery_

plan/930915.pdf
109

Species Habitat Rationale Source 

occur in conifer forests. 

Bryophyte beds are an 

important substrate.

Fleshy-fruit 

gladecress 

(Leavenworthia 

crassa) 2

PCEs: (1) Shallow-soiled, 

open areas with exposed 

limestone bedrock or 

gravel that are dominated 

by herbaceous vegetation 

characteristic of glade 

communities. (2) Open or 

well-lighted areas of 

exposed limestone 

bedrock or gravel that 

ensure fleshy-fruit 

gladecress plants remain 

unshaded for a significant 

portion of the day. (3) 

Glade habitat that is 

protected from both native 

and invasive, nonnative 

plants to minimize 

competition and shading 

of fleshy-fruit gladecress.

Technical consultation with 

USFWS biologist indicated 

that this species will not 

persist in soy or cotton 

fields due to the competing 

vegetation.

http://ecos.fws.gov/speciesProfile/prof

ile/speciesProfile.action?spcode=Q12

K#crithab

http://www.gpo.gov/fdsys/pkg/FR2014-08-26/pdf/2014-19558.pdf

Email communication (Holbrook, S. 

(2015, June 17). 

Geocarpon 

minimum (No 

common name)

This species grows on 

sandstone glades and 

outcrops as well as 

bare, sparsely vegetated 

areas where the soil 

contains relatively large 

amounts of magnesium 

and sodium salts (US 

FWS, 1993). 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

the sandstone glades and 

outcrops where this 

species is expected to be 

found. 

USFWS. 1993. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/930726.pdf

Goldenrod, 

Blue Ridge 

(Solidago 

spithamaea)

This species grows on 

rock outcrops and 

vertical to near vertical 

cliffs in southern 

Appalachians of 

western North Carolina 

and extreme eastern 

TN. Rocky summits 

and cliffs usually 

appear as smaller-scale 

patchy habitats 

embedded in larger 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rock outcrops and 

vertical cliffs. 

USFWS. 1987. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/blueridge%20goldenrod%20r

p.pdf

 2 Bold text indicates the four species with effects determination “may affect, likely to adversely affect”.
110

Species Habitat Rationale Source 

forest consisting of 

spruce-fir or northern

hardwoods or 

occasionally high 

elevation red oak forest 

(US FWS, 1987). 

Grass, 

Tennessee 

yellow-eyed 

(Xyris 

tennesseensis)

Xyris tennessensis is a 

rare perennial monocot 

that is an obligate 

wetland plant that 

prefers relatively high 

pH seeps and 

streambanks. An 

Obligate wetland plant 

that is restricted to 

calcareous seeps, fens, 

and spring runs (US 

FWS, 2014). 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

wetlands. 

USFWS. 2014. Five Year Review. 

http://ecos.fws.gov/docs/five_year

_review/doc4360.pdf

Harperella 

(Ptilimnium 

nodosum)

Harperella is known 

from only two locations 

in North Carolina. One 

population occurs in the 

Tar River in Granville 

County. Another 

population was 

reintroduced to the 

Deep River recently 

after the original 

population known from 

that area disappeared. 

This population occurs 

in Chatham County, but 

the river serves as the 

divide between 

Chatham and Lee 

counties (US FWS, 

1991). 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

river habitats. 

USFWS. 1991. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/910305b.pdf

Iris, dwarf lake 

(Iris lacustris)

The dwarf lake iris 

grows along the 

northern shorelines of 

lakes Michigan and 

Huron in Wisconsin, 

Michigan and Ontario, 

Canada. It typically 

occurs in shallow soil 

over moist calcareous 

sands, gravel and beach 

rubble. Sunlight is one 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

shoreline coniferous 

forests.

USFWS. 2013. Recovery Plan.

http://ecos.fws.gov/docs/recovery_

plan/

DLI%20RP%20FINAL%20AUG2

013_1.pdf
111

Species Habitat Rationale Source 

of the most critical 

factors to the growth 

and reproduction of the 

species and partly 

shaded or sheltered 

forest edges are optimal 

for sexual reproduction. 

Some form of 

disturbance is also 

required to maintain the 

forest openings that 

provide these partial 

shade conditions. The 

species is most often 

associated with 

shoreline coniferous 

forests dominated by 

northern white cedar 

and balsam fir. The 

principal limiting factor 

for dwarf lake iris is the 

availability of this 

suitable shoreline 

habitat (US FWS, 2013, 

pp. 6-7).

Lichen, rock 

gnome 

(Gymnoderma 

lineare)

Rock gnome lichen is 

primarily limited to 

vertical rock faces 

where seepage water 

from forest soils above 

flows during (and only 

during) very wet times. 

It appears the species 

needs a moderate 

amount of light, but that 

it cannot tolerate highintensity solar radiation. 

It does well on moist, 

generally open, sites, 

with northern 

exposures, but needs at 

least partial canopy 

coverage where the 

aspect is southern or 

western

Rock gnome lichen is 

known from the 

Southern Appalachian 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

high elevation vertical 

rock faces where the 

species occurs.

http://www.fws.gov/raleigh/specie

s/es_rock_gnome_lichen.html
112

Species Habitat Rationale Source 

Mountains of North 

Carolina and South 

Carolina, Tennessee, 

and Georgia, in areas of 

high humidity, either at 

high elevations, where 

it is frequently bathed 

in fog, or in deep 

gorges at lower 

elevations.

Lyrate 

bladderpod 

(Lesquerella 

lyrata)

Limestone glades Technical consultation with 

USFWS biologist indicated 

that this species will not 

occur in corn, soy, or 

cotton fields within the

range

http://ecos.fws.gov/docs/recovery_pla

n/961017.pdf

Email communication (Holbrook, S. 

(2015, June 17). 

Orchid, eastern 

prairie fringed 

(Platanthera 

leucophaea)

The eastern prairie 

fringed orchid occurs in 

a wide variety of 

habitats, from mesic 

prairie to wetland 

communities such as 

sedge meadows, marsh 

edges and even fens and 

sphagnum bogs. It 

requires full sunlight for 

optimum growth and 

flowering, which 

restricts it to grass- and 

sedge-dominated plant 

communities. The 

substrate of the sites 

where it occurs ranges 

from more or less 

neutral to mildly 

calcareous, typically 

glacial soils. It is often 

early successional, but 

can be maintained in 

mid- to late

successional wetlands 

that remain open and 

sunny (US FWS, 1999, 

pp. 6-7).

The proposed dicamba 

DGA uses are not 

expected to overlap with 

grass or sedgedominated plant 

communities.

USFWS. 1999. Recovery Plan.

http://ecos.fws.gov/docs/recovery_

plan/990929.pdf
113

Species Habitat Rationale Source 

Pogonia, small 

whorled (Isotria 

medeoloides)

The small whorled 

pogonia occurs on 

upland sites in mixeddeciduous or mixed 

deciduous/coniferous 

forests that are 

generally in second- or 

third-growth 

successional stages. It 

occurs on both fairly 

young and maturing 

forest stands. Most 

occurrences include 

sparse to moderate 

ground cover in the 

species’ microhabitat, a 

relatively open 

understory canopy, and 

proximity to features 

that create long 

persisting breaks in the 

forest canopy. Soils at 

most sites are highly 

acidic and nutrient 

poor, with moderately 

high soil moisture 

values. Light 

availability could be a 

limiting factor for this 

species. The one 

Illinois site is unusual 

in being on a dry, steep, 

thinly forested slope 

atop a vertical 

sandstone bluff. The 

one Ohio site is along 

the Ohio River in a 

typical Appalachiantype forest association 

(US FWS, 1992, pp. 

23-24).

The proposed dicamba 

DGA uses are not 

expected to overlap with 

mixed 

deciduous/coniferous 

forests.

USFWS. 1992. Recovery Plan.

http://ecos.fws.gov/docs/recovery_

plan/921113b.pdf

Pondberry 

(Lindera 

melissifolia)

Associated with 

seasonally flooded 

wetlands. Found on 

wet edges of sandy 

sinks, ponds, and 

swampy depressions. 

Shade tolerant (US 

FWS, 1993). 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

wetlands. 

USFWS. 1993. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/930923a.pdf
114

Species Habitat Rationale Source 

Potato-bean, 

Price's (Apios 

priceana)

Found in open forests 

along the edges of 

forests, creeks, and 

rivers (US FWS, 1993, 

p. executive summary).

The proposed dicamba 

DGA uses are not 

expected to overlap with 

forests, or water bodies.

USFWS. 1993. Recovery Plan

http://ecos.fws.gov/docs/recovery_

plan/930210.pdf

Prairie-clover, 

leafy (Dalea 

foliosa)

Leafy prairie-clover is 

found only in open 

limestone cedar glades, 

limestone barrens, and 

dolomite prairies which 

have shallow, silt to 

silty clay loam soils 

over flat and often 

highly fractured, 

horizontally bedded 

limestone or dolomite 

with frequent expanses 

of exposed bedrock at 

surface. Elevations are 

typically between 550 

and 700 feet. These 

habitats experience high 

surface and soil 

temperatures, generally 

have low soil moisture 

but are wet in the spring 

and fall and become 

droughty in summer. 

The distribution of 

glade, barren, and dry 

to wet dolomite prairie 

at any particular site 

varies and leads to a 

mosaic of soils and 

their associated plant 

communities (USFWS, 

1996, p.13).

The proposed dicamba 

DGA uses are not 

expected to overlap with 

prairies or areas with 

visible bedrock.

USFWS. 1996. Recovery Plan.

http://ecos.fws.gov/docs/recovery_

plan/900919b.pdf

Quillwort, 

Louisiana 

(Isoetes 

louisianensis)

This species grows in 

sandy soils and gravel 

bars in or near shallow 

blackwater streams and 

overflow channels in 

riparian woodland. 

bayhead forests of fine 

flatwoods and upland

longleaf pine (USFWS, 

1996). 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

streams, overflow 

channels, or riparian 

woodlands. 

USFWS. 1996. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/960930b.pdf
115

Species Habitat Rationale Source 

Rock-cress, 

Braun's (Arabis 

perstellata)

Braun’s rockcress 

occurs on the slopes of 

calcareous mesophytic 

and sub-xeric forest 

types. The occurrence 

of this species does not 

appear to be limited to a 

particular slope aspect, 

elevation, or moisture 

regime within the slope 

forests. It is, however, 

sun intolerant and 

always occurs in at least 

partial shade. The 

largest and most 

vigorous populations 

occur on moist mid- to 

upper slope sites. Plants 

are often found around 

rock outcrops, protected 

sites on the downslope 

side of tree bases, and 

sites of natural 

disturbance, such as 

talus slopes and animal 

trails. It is rarely found 

growing among the

Leaf litter and 

herbaceous cover of the 

forest floor (US FWS, 

1997). 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

calcareous mesophytic 

and sub-xeric forested 

systems. 

USFWS. 1997. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/970722.pdf

Rosemary, 

Cumberland 

(Conradina 

verticillata)

This species is found on 

rocky river bars 

composed of unsorted 

boulders, cobbles, 

gravel and sand, with 

the largest populations 

occurring in open, 

washed-out areas near 

the centers of these 

bars. The essential 

habitat requirements of 

this species are: open to 

barely shaded sites; 

moderately deep, sandy, 

well-drained soils with 

no visible organic 

matter; periodic 

forceful flooding to 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers. 

USFWS. 2011. Five Year Review. 

http://ecos.fws.gov/docs/five_year

_review/doc3629.pdf
116

Species Habitat Rationale Source 

maintain openness; 

topographic features to 

enhance sand 

deposition; and, 

perhaps, periods of 

inundation of at least 

two weeks to induce 

rooting at the lower 

nodes (pg. 8) (US FWS, 

2011). 

Sandwort, 

Cumberland 

(Arenaria 

cumberlandensi

s)

This species is 

restricted to sandstone 

rock houses, ledges, and 

solution pockets on 

sandstone rock faces; 

The species is found on 

the sandy floors of rock 

houses, in solution 

pockets on the face of 

sandstone cliffs, and on 

ledges beneath 

overhanging sandstone 

(pg. 4) (US FWS, 

1996). 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

sandstone rock houses, 

ledges, or rock faces. 

USFWS. 1996. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/960620.pdf

Skullcap, largeflowered 

(Scutellaria 

montana)

This species occurs in 

slope, ravine, and 

stream-bottom forests 

in northwestern Georgia 

and adjacent 

southeastern Tennessee. 

Habitat loss and lack of 

information on 

appropriate 

management are the 

factors limiting the 

number of viable 

populations (US FWS, 

1996). 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

ravine and streambottom forests. 

USFWS. 1996. Recovery Plan. 

http://ecos.fws.gov/docs/recovery_

plan/960515.pdf

Spiraea, 

Virginia 

(Spiraea 

virginiana)

Spiraea virginiana is 

found along the banks 

of high gradient 

sections of second and 

third order streams, or 

on meander scrolls and 

point bars, natural 

levees, and other 

braided features of 

lower reaches (often 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rivers, streams, creeks, 

or other water bodies.

USFWS. 1992. Recovery Plan.

http://ecos.fws.gov/docs/recovery_

plan/921113a.pdf
117

Species Habitat Rationale Source 

near the stream mouth). 

The habitat is in oftdisturbed early 

successional areas. 

Occasional flood 

scouring reduces 

shading and seems to be 

essential, although the 

spiraea can tolerate 

some overstory growth 

(US FWS, 1992, pp.17-

18.).

Sunflower, 

whorled 

(Helianthus 

verticillatus)

This species

occurs in remnant 

prairie habitats found

in uplands and swales 

of headwater

streams in the Coosa 

River watershed in

Georgia and Alabama 

and in the East

Fork Forked Deer and 

Tuscumbia

Rivers’ watersheds in 

Tennessee.

(US FWS 2014, p. 

50993)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

prairie habitats.

USFWS. 2014. Federal Register: 

Designation of Critical Habitat. 

http://www.gpo.gov/fdsys/pkg/FR2014-08-26/pdf/2014-19558.pdf

Thistle, 

Pitcher's 

(Cirsium 

pitcheri)

It occurs on nonforested sand dunes of 

several types (grassland 

dunes, simple linear 

beach foredunes, 

continuous and 

discontinuous dune 

complexes), sand 

beaches, and sandy 

blowouts, primarily 

occurring around the 

Great Lakes (US FWS, 

2002, p. 23-27).

The proposed dicamba 

DGA uses are not 

expected to overlap with 

sand dunes, sand 

beaches, or sandy 

blowouts.

USFWS. 2002. Recovery Plan.

http://ecos.fws.gov/docs/recovery_

plan/020920b.pdf

Alabama 

canebrake 

pitcher-plant 

(Sarracenia 

rubra 

alabamensis)

Occurs in sandhill 

seeps, swamps, and 

bogs along the fall-line 

of central Alabama. 

Colony sites are wet 

much of the year and 

are often characterized 

as wet bogs or wet 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

seeps, swamps or bogs. 

1992 USFWS Recovery Plan: 

Alabama Canebrake Pitcher Plant

2012 USFWS Alabama Canebrake 

Pitcher-Plant

(Sarracenia rubra ssp. 

alabamensis)
118

Species Habitat Rationale Source 

flatwoods. Within this 

general habitat type, 

colony health seems to 

be a function of 

unaltered hydrology 

and maintenance of an 

early successional stage 

in which competing 

woody vegetation is 

limited. Naturally 

occurring fires and 

hydrological conditions 

control the pioneering 

of woody species on 

these sites (USFWS 

1992)

5-Year Review:

Summary and Evaluation

Alabama leather 

flower 

(Clematis 

socialis)

Occurs in mesic flats,

specifically in right-ofways, bush-hogged 

areas, forests that have 

been selectively logged 

(USFWS 1989)

Open grass-seed-rush 

prairie areas and 

adjoining hardwood 

swamp forests

(USFWS 2010)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

mesic flats or forests.

1989 USFWS Alabama leather 

flower recovery plan

2010 USFWS Alabama leather 

flower 5-year review

Alabama streaksorus fern 

(Thelypteris 

pilosa var. 

alabamensis)

All known Alabama 

occurrences of the 

Alabama streak-sorus 

fern are found on 

Pottsville sandstone, 

where plants grow in 

crevices and rough 

surfaces on the 

roofs and floors of 

sandstone rockhouses 

formed along these 

cliffs (Watkins and 

Farrar 2002). 

The plants typically 

occur on moist, shady 

sites such as ceilings of 

rockhouses, ledges 

beneath sandstone 

overhangs, and on 

exposed cliff faces 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

sandstone rockhouses. 

2014 USFWS Alabama streaksorus fern (Thelypteris 

burksiorum) 5-year Review:

Summary and Evaluation. Page 7.

Available at:

http://ecos.fws.gov/docs/five_year

_review/doc4363.pdf
119

Species Habitat Rationale Source 

(USFWS 1996). 

Locations vary in slope 

aspect and shade 

coverage, from 

completely shaded to 

partially sunny on 

exposed bluff faces. 

Sites are usually 

directly above or a short 

distance from the river, 

are shaded to partially 

sunny, and have 

substrates that are kept 

moist by water vapor 

from the river and upslope runoff over the 

sandstone (USFWS

1996). (USFWS 2014)

Ashy dogweed 

(Thymophylla 

tephroleuca)

Occurs in the cenizablackbrushcreosotebush brush 

community in the South 

Texas Plains vegetation 

area; however, this site 

may have originally 

been grassland. Noted 

to grow in open areas 

on fine-sandy loam, 

however the only 

known population 

occurs on MaverickCaterina soil 

association, which is 

clayey, saline, deep to 

shallow, fine textured, 

and slowly permeable. 

Underlying geology is 

the Laredo Formation, 

composed of Eocene 

sandstones and clays. 

The habitat probably 

once supported a 

greater diversity of 

plants, but dominant 

plants now are 

buffelgrass (Cenchrus 

ciliaris), mequite 

(Prosopis glandulosa), 

goatbush (Castela 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

plains. 

1987 USFWS Ashy Dogweed 

(Thymophylla tephroleuca) 

Recovery Plan 
120

Species Habitat Rationale Source 

texana), Cenizo 

(Leucophyllum 

frutescens), anacahuita 

(Cordia boissieri), 

yucca (yucca spp), and 

javelina brush 

(Microrhamnus 

ericoides) (USFWS 

1987)

Black lace 

cactus 

(Echinocereus 

reichenbachii 

var. albertii)

This species is found in 

the vicinity of dense 

brush, but grows in 

mostly open, unshaded 

areas (USFWS 2009)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

areas of dense brush. 

2009 USFWS Black Lace Cactus

(Echinocereus reichenbachii var. 

albertii)

5-year Review:

Summary and Evaluation

Black spored 

quillwort 

(Isoetes 

melanospora)

Black-spored quillwort 

is restricted to shallow, 

flat bottomed 

depressions on granitic 

outcrops in the 

piedmont region of 

Georgia. Depressions 

are entirely rock 

rimmed and generally 

occur near the summit, 

with most water 

accumulating from 

direct rainfall and little 

flowing water to 

provide nutrient input. 

(USFWS 2008)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

wetlands. 

2008 USFWS Granite Outcrop 

Plants 5-year Review. Page 8. 

Available at:

http://ecos.fws.gov/docs/five_year

_review/doc1987.pdf

Bunched 

arrowhead 

(Sagittaria 

fasciculata)

Obligate wetland 

species. Saturated to 

flooded soils. 

Undisturbed sites are 

typically located just 

below the origin of 

slow, continuous seeps 

on gently sloping 

terrain in deciduous 

woodlands (USFWS 

1983)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

wetlands. 

1983 USFWS Bunched Arrowhead 

Recovery Plan.

Bunched cory 

cactus 

(Coryphantha 

ramillosa)

The species grows on 

limestone in 

xerophyllous scrub and 

in the desert on bare 

rock, talus, or scree. 

Coryphantha ramillosa

also grows in 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

desert. 

1989 USFWS Bunched Cory 

Cactus (Cory Dhantha ramillosa)

Recovery Plan
121

Species Habitat Rationale Source 

Chihuahuan Desert 

succulent scrub on 

rocky slopes, ledges, 

and gravelly flats on 

Santa Elena or 

Boquillas limestones

(USFWS 1989)

Canby's 

dropwort 

(Oxypolis 

canbyi)

Coastal plains -

specifically in pond 

cypress savannas, the 

shallows and edges of 

cypress pond/pine 

sloughs, and wet pine 

savannas. These are 

shallowly flooded, open 

habitats. Found in 

natural ponds 

dominated by cypress, 

grass-sedge dominated 

Carolina bays.

(USFWS 1990)

Wetlands (USFWS 

2010)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

wetlands. 

1990 USFWS Canby's dropwort 

recovery plan

2010 USFWS Canby's dropwort 5-

year review

Chisos 

Mountain 

hedgehog 

Cactus 

(Echinocereus 

chisoensis var. 

chisoensis)

Alluvial flats with 

Chihuahuan desert 

scrub vegetation 

(USFWS 1993)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

deserts.

1993 USFWS Chisos Mountain 

hedgehog cactus recovery plan

Cooley's 

meadowrue 

(Thalictrum 

cooleyi)

Grassland/herbaceous, 

woody wetland, and 

herbaceous wetlands (p. 

i). (USFWS 1994)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

wetlands. 

1994 USFWS Recovery Plan

Davis' green 

pitaya 

(Echinocereus 

viridiflorus var. 

davisii)

Chichuahuan desert in a 

semi-arid grassland. 

(USFWS 1984)

Outcrops of Caballos 

Novaculite Formation; 

found in cracks and 

crevices. (USFWS 

2012)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

desert. 

1984 USFWS 5-Year Reviews of 

23 Southwestern Species

2012 USFWS Davis' green pitaya 

and Nellie's cory cactus 5-year 

review
122

Species Habitat Rationale Source 

Dwarf-flowered 

heartleaf 

(Hexastylis 

naniflora)

Along bluffs and northfacing slopes, boggy 

areas along streams, 

and adjacent hillsides 

and ravines with acid, 

sandy loam soils in 

deciduous forests

The proposed dicamba 

DGA uses are not 

expected to overlap with 

wetlands or bluffs. 

USFWS NC State Herbarium Fact 

Sheet - Dwarf-flowered heartleaf

Florida torreya 

(Torreya 

taxifolia)

The Florida torreya is a 

dioecious coniferous 

tree found in the slope 

forest (FNAI 2010) that 

cover hammocks, steep, 

deeply shaded 

limestone slopes and 

wooded ravines along 

the east side of the 

Apalachicola River in 

Florida (Fig. 1), and 

adjacent Lake Seminole 

in Georgia. Soils in 

these areas are within 

the orders Alfisols and 

Mollisols. 

(USFWS 2010)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

forests.

USFWS 2010. Torreya taxifolia 

(Florida torreya) 5-Year Review. 

Page 13.

Available at:

http://ecos.fws.gov/docs/five_year

_review/doc3258.pdf

Fringed 

campion (Silene 

polypetala)

Occurs in hardwood 

forests in bottomland 

and ravines. It is often 

on fairly steep slopes of 

deep ravines or northfacing hillsides, 

sometimes on nearly 

level ground, 

particularly in 

flatwoods developed on

Iredell soils. Occurs 

mainly in small isolated 

patches of rich 

hardwood. The great 

majority of populations 

occur in the watershed 

of the Apalachicola 

River and its tributary, 

the Flint River. 

(USFWS 1996)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

forests. 

1996 USFWS Technical Agency 

Draft Recovery Plan for Fringed 

Campion (Salene polypetula)

USFWS Species Profile: Fringed 

campion (Silene polypetala)

(http://ecos.fws.gov/speciesProfile/

profile/speciesProfile.action?spcod

e=Q21P)
123

Species Habitat Rationale Source 

Gentian 

pinkroot 

(Spigelia 

gentianoides)

Well drained upland 

pinelands; longleaf 

pine-wiregrass 

ecosystem (USFWS 

2012)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

forests.

2012 US FWS Gentian pinkroot 

5-Year Review

Golden sedge 

(Carex lutea)

The land surface is 

characterized by large 

areas of broad, level 

flatlands and shallow 

stream basins. Golden 

sedge grows in sandy 

soils overlying coquina 

limestone deposits, 

where the soil pH is 

unusually high for this 

region, typically 

between 5.5 and 7.2. 

Soils supporting the 

species are very wet to 

periodically shallowly 

inundated. The species 

prefers the ecotone 

(narrow transition zone 

between two diverse 

ecological 

communities) between 

the pine savanna and 

adjacent wet hardwood 

or hardwood/conifer 

forest. Most plants 

occur in the partially 

shaded savanna/swamp 

where occasional to 

frequent fires favor an 

herbaceous ground 

layer and suppress 

shrub dominance. Other 

species with which this 

sedge grows include 

tulip poplar 

(Liriodendron 

tulipifera), pond 

cypress (Taxodium 

ascendens), red maple 

(Acer rubrum var. 

trilobum), wax myrtle 

(Myrica cerifera var. 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

wetlands.

2009 USFWS Golden Sedge 

(Carex lutea) Five-Year Review: 

Summary and Evaluation
124

Species Habitat Rationale Source 

cerifera), colic root 

(Aletris farinosa), and 

several species of 

beakrush 

(Rhynchospora spp.). 

At most sites, golden 

sedge shares its habitat 

with Cooley's 

meadowrue (Thalictrum 

cooleyi), another 

federally endangered 

plant species, and with 

Thorne's beakrush 

(Rhynchospora 

thornei), a species of 

concern to us. (USFWS 

2009)

Bat, gray 

(Myotis 

grisescens)

Gray bats are year 

round cave dwellers, 

although they may also 

use mines. They 

hibernate from as late 

as November 10 to late 

March or early April. 

At other times, they 

forage from late 

afternoon through early 

morning within 12-20 

miles of their caves, 

most often within 4 

miles of their caves. 

Foraging habitat is 

strongly correlated with 

open waters (rivers, 

lakes, reservoirs) (US 

FWS, 2009, pp. 6-7). 

Historically, rivers near 

caves provided both 

foraging habitat and 

riparian tree vegetation 

that provided cover. 

Small lakes and 

reservoirs where cover 

is not too distant also 

provide foraging 

habitat. Bats will 

opportunistically forage 

in riparian and upland 

areas, particularly when 

The proposed dicamba 

DGA uses are not 

expected to encompass 

caves or the forest/open 

water areas where bats 

forage.

USFWS. 1982. Recovery Plan.

http://ecos.fws.gov/docs/recovery_

plan/820701.pdf

USFWS. 2009. 5-Year Review.

http://ecos.fws.gov/docs/five_year

_review/doc2625.pdf
125

Species Habitat Rationale Source 

migrating (US FWS, 

1982. pp. 6-7).

Green pitcherplant 

(Sarracenia 

oreophila)

Habitats can be 

generally grouped into 

two types: stream banks 

(considered ephemeral) 

and upland bogs. 

Upland bogs, fire 

dependent, range from 

open to forested, 

underlain by semiimpervious clay layers 

(USFWS 2013)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

wetlands. 

2013 US FWS Green pitcher plant 

(Sarracenia oreophila) 5-Year 

Review: Summary and Evaluation

Hairy 

rattleweed 

(Baptisia 

arachnifera)

22 extant populations 

occur entirely in Lower 

Coastal Plain of 

Georgia, 125 square 

miles over northern 

Brantley County and 

southeastern corner of 

Wayne County. 

Longleaf slash-pine 

flatwoods with sparse 

canopy, fewer larger 

shrubs, greater light 

penetration and greater 

cover of herbs (mainly 

wiregrass) and low 

shrubs of the Lower 

Coastal Plain of 

Georgia. Early 

successional 

characteristics of open 

canopy and low 

abundance of larger 

shrubs. Mesic pine 

lowland forest or pine 

flatwoods. Also occurs 

in floristically similar 

but more open pinewire grass (Aristida 

stricta) shrub 

woodlands with 

occasional oaks 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

the margins of cultivated 

land. 

2011 USFWS Hairy Rattleweed 

(Baptisia arachnifera) 5-Year 

Review: Summary and Evaluation

1984 USFWS Recovery Plan for 

Hairy Rattleweed (Baptisia 

arachnifera)
126

Species Habitat Rationale Source 

(Quercus laevis, Q. 

virginiana, Q. nigra). 

Fire adapted 

communities that would 

naturally burn every 2-4 

years. Most abundant 

in communities with the 

early successional 

characteristics of open 

canopy and low 

abundance of larger 

shrubs. Presently 

occurs in slash-pine 

plantations within its 

range, also along 

highway/utility/logging 

road ROWs and some 

natural communities 

(longleaf pinewiregrass-shrub 

communities), and 

margins of cultivated 

land (generally corn, 

tobacco, and pasture). 

Level to gently sloping 

land. Often adjacent 

to/grades into pocosin 

or bay swamp habitats 

scrub-shrub wetlands 

toward the wetter end 

of spectrum to habitats 

typical of longleaf pineturkey oak communities 

towards the drier end. 

(USFWS 2011)

Heller's 

blazingstar 

(Liatris helleri)

Heller’s blazing star 

habitat consists of rock 

outcrops, ledges, cliffs, 

and balds at high

elevations (USFWS 

1989)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

rock outcrops or cliffs. 

1989 USFWS Recovery Plan

for Liatris helleri (Heller’s Blazing 

Star)

Hinckley oak 

(Quercus 

hinckleyi)

Quercus hincklevi

occurs in an arid 

subtropical climate. 

Climatologists place it 

in the Trans-Pecos 

climatic area of Texas, 

which is extremely 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

forests. 

1991 USFWS Hinckley Oak

(Quercus hinckleyi)

5-Year Review:

Summary and Evaluation 
127

Species Habitat Rationale Source 

variable because of 

topographic differences. 

The area generally has 

great daily temperature 

fluctuations and an arid 

profile where 

evaporation exceeds 

precipitation. The 

average temperature is 

approximately 30.40°C 

(86.80°F), with an 

average

precipitation of 23.4 cm 

(9.2 inches) (USFWS 

1991)

Houghton's 

goldenrod 

(Solidago 

houghtonii)

This plant grows on the 

shores of the Great 

Lakes, mainly Lake 

Huron and Lake 

Michigan, at the 

Michigan-Ontario 

border. (USFWS 2011)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

shores. 

2011 US FWS Houghton’s 

Goldenrod (Solidago houghtonii

A. Gray, Asteraceae)

5-Year Review:

Summary and Evaluation 

Johnston's 

frankenia 

(Frankenia 

johnstonii)

Open or sparsely 

vegetated rocky 

gypsum hillsides or 

saline flats. In Texas, 

occur in mesquite 

blackbrush community 

(USFWS 1988)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

saline flats. 

1988 USFWS Johnston's 

Frankenia (Frankenia johnstonii) 

Recovery Plan

2003 USFWS Endangered and 

Threatened Wildlife and Plants; 

Delisting the plant Frankenia 

johnstonii (Johnston's frankenia) 

and Notice of Petition Finding.68 

FR 27961

Kentucky glade 

cress 

(Leavenworthia 

exigua 

laciniata)

Leavenworthia exigua 

var. laciniata

is typically found in 

cedar or limestone 

glades (Baskin and 

Baskin 1981, p. 243), 

which are described by 

Baskin and Baskin 

(1999, p. 206) as ‘‘open 

areas of rock pavement, 

gravel, flagstone, and/or 

shallow soil in which 

occur natural, longpersisting (edaphic 

climax) plant 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

wetlands. 

USFWS 2014. Designation of 

Critical Habitat for Leavenworthia 

exigua var. laciniata (Kentucky 

Glade Cress); Final rule. Page 

25691.

Available at:

http://www.gpo.gov/fdsys/pkg/FR2014-05-06/pdf/2014-10050.pdf
128

Species Habitat Rationale Source 

communities dominated 

by angiosperms and/or 

cryptogams.’’ 

L. exigua var. laciniata 

is also known from 

gladelike areas such as 

overgrazed pastures, 

eroded shallow soil 

areas with exposed 

bedrock, and areas 

where the soil has 

been scraped off the 

underlying bedrock 

(Evans and Hannan 

1990, p. 8). These 

disturbed areas are 

gladelike in the 

shallowness or nearabsence of their soils, 

saturation, and/or 

inundation during the 

wet periods of late fall, 

winter, and early spring 

and then frequently dry 

below the permanent 

wilting point during the 

summer (Baskin and 

Baskin 2003, p. 101). 

(USFWS 2014, 

p25691) 

Kral's waterplantain 

(Sagittaria 

secundifolia)

This taxon typically 

occurs on frequently 

exposed shoals or 

rooted among loose 

boulders in quiet pools 

up to 1 meter (3.3 feet) 

in depth. The plant is 

found in the Little

River drainage in 

Dekalb and Cherokee 

counties, the Town 

Creek drainage in 

Dekalb County, and in 

the West Sipsey Fork in

Winston County in 

Alabama. (USFWS 

1991)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

water bodies.

1991 USFWS Kral’s WaterPlantain (Saciittaria secundifolia) 

Recovery Plan
129

Species Habitat Rationale Source 

Large-fruited 

sand-verbena 

(Abronia 

macrocarpa)

Post oak savanna region 

of eastern Texas. 

Documented wild 

populations occur in 

acid, relatively infertile 

sandy soils of the 

Arenosa, SilsteadPadina, Pickton, and

Wolfpen series lie 79-

127 cm deep over sandy 

clay loam. (USFWS 

2010)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

post oak savanna. 

2010 USFWS 5-year review 

Large-fruited Sand-verbena 

(Abronia macrocarpa galloway)

Little Aguja 

(=Creek) 

Pondweed 

(Potamogeton 

clystocarpus)

Grows in alluvial 

substrates of shallow, 

protected area of Little 

Aguja Creek. Species 

located in pools along 

the streambed. Flash 

floods and drought are 

part of the normal 

stream ecology 

(USFWS 1994)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

alluvial areas around 

creeks. 

1994 USFWS Little Aguja 

pondweed recovery plan 

(Potamogeton clystocarpus).

Little 

amphianthus 

(Amphianthus 

pusillus)

On granitic outcrops in 

the Piedmont 

physiographic region of 

the southeastern United 

States generally in 

eroded depressions or, 

rarely, quarry pools 

fanned on flat- to 

doming granite 

outcrops. Occur in 

shallow flat-bottomed 

pools on the crest or 

flattened slopes of 

unquarried outcrops. 

Pools might be several 

meters in diameter. 

(USFWS 2008)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

granitic outcrops.

2008 USFWS Granite Outcrop 

Plants 5-year Review

Lloyd's 

Mariposa cactus 

(Echinomastus 

mariposensis)

Hills and lower slopes 

of mesas. Occur in full 

sun on patches of 

limestone chips. 

Chihuahauan desert 

scrub community. 

(USFWS 1990)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

desert.

1990 USFWS Lloyd’s

Mariposa Cactus (Neolioydia

mariposensis) Recovery Plan

U.S. Fish and Wildlife Service 

Albuquerque, New Mexico 
130

Species Habitat Rationale Source 

Mat-forming 

quillwort 

(Isoetes 

tegetiformans)

Mat-forming quillwort 

is restricted to shallow, 

flat bottomed 

depressions on granitic 

outcrops in the 

piedmont region of 

Georgia. Depressions 

are entirely rock 

rimmed and generally 

occur near the summit, 

with most water 

accumulating from 

direct rainfall and little 

flowing water to 

provide nutrient input. 

(USFWS 2008)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

depressions on granitic 

outcrops.

2008 USFWS Granite Outcrop 

Plants 5-year Review. Page 8. 

Available at:

http://ecos.fws.gov/docs/five_year

_review/doc1987.pdf

Miccosukee 

gooseberry 

(Ribes 

echinellum)

Mixed mesophytic 

hardwoods (USFWS 

2008)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

forests. 

2008 US FWS Miccosukee 

Gooseberry 5-Year Review

Michaux's 

sumac (Rhus 

michauxii)

It is endemic to the 

inner coastal plain and 

piedmont of the 

Carolinas, Georgia, and 

Florida, where it 

occupies sandy or rocky 

open woods. It appears 

to depend upon some 

form of disturbance to 

maintain the open 

quality of its habitat. 

(USFWS 1993)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

sandy or rocky open 

woods. 

1993 USFWS RECOVERY PLAN

for Michaux’s Sumac (Rhus 

michauxii) Sargent

Michigan 

monkey-flower 

(Mimulus 

michiganensis)

Aquatic to semi-aquatic 

habitat. It is restricted to 

cold, alkaline spring 

seepages and streams, 

usually in association 

with northern white 

cedar (Thuja 

occidentalis) swamps 

formed in drainages 

found at the base of 

relatively steep, 

morainic slopes and 

bluff. Within its habitat, 

it generally flourishes 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

wetlands. 

2011 USFWS Michigan Monkeyflower (Mimulus michiganensis) 5-

Year Review: Summary and 

Evaluation

1997 USFWS Recovery Plan for 

Michigan Monkey-flower 

(Mimulus glabratus var. 

michiganensis)
131

Species Habitat Rationale Source 

best in tree canopy 

openings, along forest 

edges, or along streams 

adjacent to open, 

meadow-like areas and 

flowers abundantly 

when growing in full 

sunlight. However, it 

mostly persists as sterile 

colonies when growing 

under heavy tree 

canopy cover. (USFWS 

2011)

Surveys of some 

locations found water 

temperature ranging 

from 8.7 to 16.6° C, pH 

ranging from 7.66-8.4, 

conductivity ranging 

from 190 to more than 

300 umhos and high 

concentrations of 

ammonium, nitrate, and 

phosphorus. (USFWS 

1997)

Mohr's Barbara 

button 

(Marshallia 

mohrii)

Marshallia mohrii

typically occurs in 

moist, prairie-like 

openings in woodlands 

and along shale-bedded 

streams. (USFWS 

1991)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

wetlands. 

1991 USFWS RECOVERY PLAN

for Mohr’s Barbara’s buttons 

Marshallia mohrii Beadle & F.E. 

Boynton

Mountain 

golden heather 

(Hudsonia 

montana)

Fire maintained, keeps 

woody trees and shrubs 

down. (USFWS 2012)

Limited to chilhowee 

quartzite ledges and 

outcrops found along 

Linville Gorge. In 

watershed of the 

Linville River. Ledge 

habitats exposed to 

direct sunlight. 

Edaphically maintained 

ecotone between bare 

rock and 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

outcrops and ledges. 

2012 USFWS Mountain Golden 

Heather (Hudsonia montana) 5-

Year Review: Summary and 

Evaluation 

1983 USFWS Mountain Golden 

Heather (Hudsonia montana) 

Recovery Plan 
132

Species Habitat Rationale Source 

pine/ericaceous shrub 

community, with mtn 

golden heather local 

dominant in the 

ecotone. 

(USFWS 1983)

Mountain sweet 

pitcher-plant 

(Sarracenia 

rubra ssp. 

jonesii)

It is found in the wetter 

parts of boggy areas in 

the coastal plain from 

southern Georgia and 

northern Florida to 

southern Mississippi. 

Quite often the plants 

can be found near the 

waterline. They may 

occasionally be 

submerged. While 

submerged, it will 

capture water 

arthropods and 

tadpoles. (USFWS 

2013)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

wetlands. 

2013 USFWS Mountain sweet

pitcher plant

(Sarracenia rubra ssp. jonesii)

5-Year Review:

Summary and Evaluation

Morefield's 

leather flower 

(Clematis 

morefieldii)

It occurs in patches near 

seeps and springs in 

rocky limestone woods, 

typically at elevations 

of 800 to 11 feet, on the 

south and wouthwest 

facing slopes of 

mountains in open to 

dense juniperhardwoods 

communities

The proposed DGA uses 

are not expected to 

overlap with rocky 

limestone wood habitat 

on mountains.

1994 USFWS. Recovery Plan for 

Morefield’s leather flower 

(Clematis morefieldii). Atlanta, 

Georgia. 15 pp.

http://ecos.fws.gov/docs/recovery_

plan/940503.pdf

Navasota 

ladies'-tresses 

(Spiranthes 

parksii)

Clearly associated with 

the Post Oak Savanna 

vegetation type of eastcentral Texas. Highest 

numbers of individuals 

found in lightly 

wooded, lightly grazed 

stream banks of minor 

tributaries associated 

with the Navosta and 

Brazos drainages (2, 

p.10-11). Oak Savanna 

associates – Quercus 

stellata, Q. nigra, Q 

marilandica, Ulmus 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

savanna. 

1984 USFWS Navasota Ladies'-

tresses (Spiranthes parksii) 

Recovery Plan 
133

Species Habitat Rationale Source 

alata, Celtis laevigata, 

Ilex vomitoria, 

Forestiera ligustrina, 

Callicarpa americana, 

Ascyrum hypericoides, 

Stillingria sylvatica, 

and numerous herbs 

(USFWS 1984)

Neches River 

rose-mallow 

(Hibiscus 

dasycalyx)

Intermittent or 

perennial wetlands 

within the Neches, 

Sabine, and Angelina 

River floodplains or 

Mud and Tantabogue 

Creek basins that 

contain: 

(a) Hydric alluvial soils 

and the potential for 

flowing water when 

found in depressional 

sloughs, oxbows, 

terraces, side channels, 

or sand bars; 

(b) Native woody or 

associated herbaceous 

vegetation, largely with 

an open canopy 

providing partial to full 

sun exposure with low 

levels or no 

nonnative species. 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

wetlands. 

USFWS 2013. Designation of 

Critical Habitat for Texas Golden 

Gladecress and Neches River 

Rose-Mallow; Final Rule. Page 

56093.

Available at:

http://www.gpo.gov/fdsys/pkg/FR2013-09-11/pdf/2013-22083.pdf

Nellie cory 

cactus 

(Coryphantha 

minima)

Desert grassland. 

Restricted to the 

Caballos Naviculite 

Formation, a quartz 

formation that forms 

low-lying ridges that 

are highly resistant to 

erosion. The Nellie 

Cory cactus is usually 

found growing among 

the chips of weathered 

and physically fractured 

novaculite, often 

associated with 

spikemoss (Selaginella 

sp.). The plants follow 

the cracks in the 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

desert grassland. 

1984 USFWS Recovery Plan for 

the Nellie Cory Cactus

2012 USFWS Davis's Green 

Pitaya Echinocereus viridiflorus 

var. davisii Houghton and Nellie 

Cory Cactus Escobaria minima

(Baird) D.R. Hunt (Syn. 

Coryphantha minima Baird) Five 

Year Review 
134

Species Habitat Rationale Source 

formation (USFWS 

1984)

Has a very clumped 

distribution, caespitose, 

plants not evenly 

distributed. (USFWS 

2012)

Pecos (=puzzle, 

=paradox) 

sunflower 

(Helianthus 

paradoxus)

Pecos sunflower is a 

wetland plant that 

grows on wet, alkaline 

soils at spring seeps, 

wet meadows, stream

courses and pond 

margins. It has seven 

widely spaced 

populations in westcentral and eastern New 

Mexico and adjacent 

Trans-Pecos Texas. 

These populations are 

all dependent upon 

wetlands from natural 

groundwater deposits. 

Incompatible land uses, 

habitat degradation and 

loss, and groundwater 

withdrawals are historic 

and current threats to 

the survival of Pecos 

sunflower. (USFWS 

2005)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

wetlands. 

USFWS 2005 Final Pecos 

Sunflower Recovery Plan

Available at:

http://www.fws.gov/southwest/es/

documents/r2es/pecos_sunflower_

final_recovery_plan.pdf

Persistent 

trillium 

(Trillium 

persistens)

Found in deciduous or 

conifer deciduous forest 

of steep ravines and 

gorges, bouldered 

slopes; predominantly 

mesic slopes, but some 

dry exposed slopes. 

Wide variety of habitat 

conditions – noted to 

occur generally under a 

well developed 

overstory but also in 

open or closed canopies 

dominated by hemlock, 

hemlock-white pine, 

hemlock-beech, white 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

forests. 

1984 USFWS Persistemt Trillium 

(Trillim persistens) Recovery Plan 
135

Species Habitat Rationale Source 

pine, chestnut oakwhite oak, black-oakchestnut oak, with open 

or nearly closed shrub

cover of Rhododendron 

minus, Rhododendron 

maximum, Leucothoe 

axillaris, and all 

combinations of the 

above, including with 

no shrubs or deciduous 

shrubs only. (USFWS 

1984)

Relict trillium 

(Trillium 

reliquum)

This species is typically 

found in mature and 

undisturbed hardwood 

stands. (USFWS 1991)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

forests. 

1991 USFWS Recovery Plan

for Relict Trillium (Trillium 

reliauum Freeman)

Rough-leaved 

loosestrife 

(Lysimachia 

asperulaefolia)

Found in ecotone 

between longleaf pine 

or oak savannahs and 

wetter shrubby plant 

communities. Coastal 

plains and sandhills. 

Requires moist, open 

habitat. Associated 

with 6 different 

community types: low 

pocosin, high pocosin, 

wet pine flatwoods, 

pine savanna, 

streamhead pocosin, 

and sandhill seep. 

(USFWS 1995)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

longleaf pine or oak 

savannas.

1995 USFWS Rough-leaved 

loosestrife recovery plan

Schweinitz's 

sunflower 

(Helianthus 

schweinitzii)

Currently known from 

roadsides, power line 

clearings, old pastures, 

woodland openings, and 

other sunny to semisunny situations. 

Formerly, it probably 

occurred in prairie-like 

habitats or post oakblackjack oak savannas 

maintained by fires set 

by lightning and Native 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

prairie-like habitats. 

1994 USFWS Recovery Plan
136

Species Habitat Rationale Source 

Americans (p. i). 

(USFWS 1994)

Seabeach 

amaranth 

(Amaranthus 

pumilus)

Barrier island beaches 

of the Atlantic coast, 

inlets, temporary 

habitats, may move as 

areas become suitable 

or unsuitable habitat. 

Overwash flats at 

accreting ends of 

islands, lower foredunes 

and upper strands of 

noneroding beaches 

(landward of the 

wrackline). Does not 

occur on well-vegetated 

sites. (USFWS 1996)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

beaches. 

1996 Weakley, Bucher, Murdock 

U.S. Fish and Wildlife Service. 

1996. Recovery Plan for Seabeach 

Amaranth.(Amaranthuspumilius) 

Rafinesque). Atlanta, Georgia. 

http://ecos.fws.gov/docs/recovery_

plan/961112b.pdf.

2007 USFWS Seabeach Amaranth 

Five-Year Review; 

http://ecos.fws.gov/docs/five_year

_review/doc1068.pdf

Sensitive jointvetch 

(Aeschynomene 

virginica)

Occurs in fresh to 

slightly brackish tidal 

river systems, within 

the intertidal zone 

where populations are 

flooded twice daily. 

Typically occur in the 

estuarine meander zone 

of tidal rivers where 

sediments transported 

from upriver settle out 

and extensive marshes 

form. Need 

disturbed/open habitats 

such as: accreting point 

bars that have not yet 

been colonized by 

perennial species, low 

swales within extensive 

marshes, areas of 

nutrient deficiencies in 

saturated organic 

sediments, or areas of 

muskrat herbivory. 

(USFWS 1995)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

wetlands. 

1995 USFWS Sensitive joint-vetch 

recovery plan

2012 USFWS Sensitive joint-vetch 

5-year review
137

Species Habitat Rationale Source 

Majority are found in 

natural tidal marsh 

habitats, but also a few 

documented cases of a 

pocket marsh wetland, 

edge of a moist soybean 

field, and a mowed 

grassy strip between a 

manmade drainage 

channel and dirt road. 

(USFWS 2012)

Short's 

bladderpod 

(Physaria 

globosa)

Soils and outcrops of 

calcareous geologic 

formations along the 

mainstem or tributaries 

of the Kentucky and 

Cumberland rivers. The 

species inhabits these 

outcrops and soils 

where they occur on 

steeply sloped bluffs or 

hillsides. The 

combination of 

calcareous outcrops and 

shallow soils, steep 

slopes, and hot and dry 

conditions regulates the 

encroachment of 

herbaceous and woody 

species that exclude 

Short’s bladderpod 

from vegetation 

communities present on 

more mesic sites. 

The proposed dicamba 

DGA uses are not 

expected to occur in 

areas where calcareous 

outcrops, shallow soils, 

steep slopes and hot and 

dry conditions prevent 

the encroachment of 

herbaceous and woody 

species such as soybean 

and cotton.

2014. USFWS. Designation of 

Critical Habitat for Physaria 

globosa (Short's bladderpod), 

Helianthus verticillatus (whorled 

sunflower), and Leavenworthia 

crassa (fleshy-fruit gladecress) 

Final Rule. Federal Register 

Federal Register Volume 79 

Number 165 August 26, 2014

http://www.gpo.gov/fdsys/pkg/FR2014-08-26/pdf/2014-19558.pdf

Short's 

goldenrod 

(Solidago 

shortii)

The habitat of Short's 

goldenrod is open areas 

in full sun or partial 

shade. Known 

occurrences are in 

limestone cedar glades, 

open eroded areas, 

edges, of open oakhickory woods, cedar 

thickets, pastures, old 

fields, power line 

rights-of-way and rock 

ledges along rights-ofway. Cedar glades and 

The proposed dicamba 

DGA salt uses are not 

expected to overlap with 

glades, woodland edges, 

pastures, or other habitat 

favorable for goldenrod 

growth.

1988 USFWS. Recovery Plan for 

Short’s Goldenrod. U.S. Fish and 

Wildlife Service, Atlanta, Georgia. 

27 pp. 

http://ecos.fws.gov/docs/recovery_

plan/shortsgrodRP.pdf

USFWS. 2007. 5-Year Review.

http://ecos.fws.gov/docs/five_year

_review/doc1609.pdf
138

Species Habitat Rationale Source 

woodland edges appear 

to be the natural habitat. 

Short's goldenrod was 

known historically and 

currently only from 

Kentucky when the 

Recovery Plan was 

written in 1988 (US 

FWS, pp. 3-4). An 

Indiana occurrence was 

located in 2001 along 

the Blue River in 

riparian habitat (US 

FWS, 2007, p. 6).

Slender rushpea 

(Hoffmannseggi

a tenella)

Occurs in patches of 

native short and midgrass prairie 

(specifically associated 

with buffalograss, 

Texas wintergrass 

(Stipa leucotrica) and 

Texas grama 

(Bouteloua rigidiseta) 

adjacent to 

watercourses, such as 

permanent or 

intermittent creeks. 

Restricted to the Texas 

Coastal Bend counties 

of Nueces and Kleberg. 

Eco-region is Gulf 

Prairies and Marshes 

biotic zone. Occurs on 

slopes (20 degrees 

max), along drainages, 

usually located in areas 

of short or sparse 

vegetation since it can't 

compete with taller 

grasses. Has been found 

on slopes close to 

mesquite-granjeno 

woodland areas and 

where shrubs are low. 

(USFWS 2008)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

prairie. 

2008 USFWS Slender Rush-pea 

(Hoffmannseggia tenella) 5 Year 

Review: Summary and Evaluation 
139

Species Habitat Rationale Source 

Small-anthered 

bittercress 

(Cardamine 

micranthera)

Native to small 

streambank seeps, 

adjacent sandbars, and 

stream edges in the Dan 

River drainage of the 

North Carolina and 

Virginia piedmont. 

(USFWS 1991)

This plant occurs in 

moist and wet, shady 

areas near streams and 

in dim woodlands. 

Small-anthered 

bittercress is known 

only from the Dan 

River basin in northcentral North Carolina 

(Stokes County) and 

south-central Virginia 

(Patrick County). 

(USFWS 1998)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

stream edges. 

1991 USFWS Recovery Plan for 

the Small-anthered bittercress 

Cardamine micranthera

1998 USFWS Recovery Plan for 

the Cardamine micranthera

Smooth 

coneflower 

(Echinacea 

laevigata)

The habitat of smooth 

coneflower consists of 

open woods, cedar 

barrens, roadsides, 

clearcuts, dry limestone 

bluffs, and power line 

rights-of-way, usually 

on magnesium- and 

calcium-rich soils 

associated with 

amphibolite, dolomite, 

or limestone (USFWS 

2011)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

open woods, barrens, or 

bluffs. 

2011 USFWS Smooth Coneflower 

(Echinacea laevigata) 5-Year 

Review: Summary and Evaluation

Sneed 

pincushion 

cactus 

(Coryphantha 

sneedii var. 

sneedii)

The Sneed and Lee 

pincushion cacti grow 

in semi-desert grassland 

(Brown, 1982). The 

Sneed pincushion 

cactus is restricted to 

limestone and grows in 

cracks on vertical cliffs 

or ledges. The Sneed 

pincushion cactus 

grows at an elevation of 

1,200-2,350 m in areas 

where the average 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

semi-desert grasslands. 

1986 USFWS Recovery Plan for 

the Sneed and Lee Pincushion

Cacti. Pages 8-9. Available at:

http://ecos.fws.gov/docs/recovery_

plan/860321b.pdf
140

Species Habitat Rationale Source 

precipitation varies 

from 19.7 to 40 cm per 

year. Edaphic 

requirements are poorly 

understood. (USFWS 

1986)

South Texas 

ambrosia 

(Ambrosia 

cheiranthifolia)

Grows in the Gulf 

coastal grasslands of 

southern Texas. The 

plant is found in 

grassland and mesquite 

shrubland habitat on 

various soils. 

Associated with sites 

where native shortgrass prairie species 

persist. Also on 

moderately disturbed 

sites such as cemeteries, 

right-of-ways, 

roadsides, parkfields, 

and eroded areas along 

creeks. (USFWS 2010)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

grasslands. 

2010 USFWS South Texas 

Ambrosia (Ambrosia 

cheiranthifolia) 5-Year Review: 

Summary and Evaluation

Star cactus 

(Astrophytum 

asterias)

Star cactus grows on 

sparsely vegetated areas 

in gravelly, saline clays 

or loams at low 

elevations in the Rio 

Grande Plains.

(USFWS 2013)

This species grows in 

grasslands and thorn 

shrub of the Rio Grande 

(US FWS 2003)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

grasslands or thorn 

shrub. 

USFWS 2013. Star Cactus

(Astrophytum asterias) 5-Year 

Review: Summary and Evaluation

Available at:

http://www.fws.gov/southwest/es/

Documents/R2ES/Star_Cactus_5-

yr_Review_FINAL_June2013.pdf

US FWS 2003. Recovery Plan. 

Available at: 

http://ecos.fws.gov/docs/recovery_

plan/031106.pdf

Swamp pink 

(Helonias 

bullata)

Swamp pink is found in 

a variety of wetland 

habitats, including 

swampy forested 

wetlands bordering 

small streams; 

headwater wetlands; 

sphagnous, hummocky, 

dense Atlantic white 

cedar swamps; Blue 

Ridge swamps;

The proposed dicamba 

DGA uses are not 

expected to overlap with 

wetlands. 

1991 USFWS Swamp Pink

(Helonias bullata)

Recovery Plan

Available at:

http://ecos.fws.gov/docs/recovery_

plan/910930c.pdf
141

Species Habitat Rationale Source 

meadows; bogs; and 

spring seepage areas 

(USFWS 1991)

Terlingua Creek 

cat's-eye 

(Cryptantha 

crassipes)

Grows on xeric, barren, 

gypsiferous, low 

rounded hills and gentle 

slopes composed of 

small platelets of stilty 

limestone in the TransPecos shrub savanah (p. 

iii). Obligate upland (p. 

iii). 

(USFWS 1994)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

shrub savanna. 

1994 USFWS Recovery Plan

Available at:

http://ecos.fws.gov/docs/recovery_

plan/940405.pdf

Texas ayenia 

(Ayenia 

limitaris)

This species is 

associated with forest 

and scrubland of river 

flood plains and deltas 

in south Texas and 

northern Mexico. 

Occurs in open ground 

or under an open 

canopy, within or on the 

edges of thickets, on 

dry, alluvial clay soils. 

(USFWS 2010)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

forests or scrubland. 

2010 USFWS Texas Ayenia 

(Tamaulipan Kidneypetal), Ayenia 

limitaris Cristóbal, 5-Year Review

Available at:

http://ecos.fws.gov/docs/five_year

_review/doc3241.pdf

Texas Golden 

Gladecress 

(Leavenworthia 

texana)

Open, sunny exposures 

of Weches outcrops 

within Weches glade 

plant communities that 

are characterized by the 

species listed in 

Table 1, with relatively 

thin, rocky soils that are 

classified within 

Nacogdoches, 

Trawick, or Bub soils 

mapping units as 

identified by the NRCS 

soil survey maps. There 

must be bare, exposed 

bedrock on top-level 

surfaces or rocky ledges 

with very shallow 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

Weches outcrops. 

USFWS 2013. Designation of 

Critical Habitat for Texas Golden 

Gladecress and Neches River 

Rose-Mallow; Final Rule. Page 

56087.

Available at:

http://www.gpo.gov/fdsys/pkg/FR2013-09-11/pdf/2013-22083.pdf
142

Species Habitat Rationale Source 

depressions where 

rainwater can pool or 

seepage can collect. 

(USFWS 2013)

Texas poppymallow 

(Callirhoe 

scabriuscula)

Rolling Plains 

Vegetation zone of 

Texas. Deep, alluvial 

sands deposited in 

Runnels County, Texas 

(USFWS 1985)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

the Rolling Plans. 

1985 USFWS Texas poppymallow (Callirhoe scabriuscula): 

Recovery Plan

Texas prairie 

dawn-flower 

(Hymenoxys 

texana)

This plant grows only 

in the grasslands of the 

Gulf Coastal Plain in 

Texas. It can be found 

on open, barren 

stretches of saline sandy 

soil at the base of Mima 

mounds. (USFWS 

1989)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

grasslands. 

1989 USFWS Hymenoxys texana

Recovery Plan

Texas 

snowbells 

(Styrax texanus)

Endemic to cliffs along 

rivers, streams, and dry 

creek beds in the 

Edwards Plateau. 

Grows in limestone 

crevices of creek and 

river bluffs. Elevations 

are 30m to 914 m. 

Shallow soils, wide 

range of textures. 

Lightly wooded vertical 

limestone and dolomite 

cliffs, mapped as 

Segovia and Fort 

Terrett members of the 

Edwards Limestone, the 

Devil’s River 

Limestone, and the 

Glen Rose Formation. 

Numerous trees, shrubs, 

and herbs associated. 

(USFWS 1987)

Moist habitats like river 

drainages, canyons, and 

draws, which are 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

cliffs. 

1987 USFWS Texas Snowbells 

(Styrax texana) Recovery Plan 

2008 USFWS Texas Snowbells 

(Styrax platanifolius ssp. Texanus) 

5-Year Review Summary and 

Evaluation 
143

Species Habitat Rationale Source 

abundant in the 

Edwards Plateau. 

Surface water may not 

be present, but sites 

have subsurface water 

or collect runoff. Most 

plants are found where 

they get at least partial 

shade during the day 

from surrounding 

vegetation. Many occur 

on level terrain, but are 

most often described on 

vertical cliffs possibly 

because of herbivory on 

more accessible terrain. 

(USFWS 2008)

Texas trailing 

phlox (Phlox 

nivalis ssp. 

texensis)

Sandy soils of open 

pine woodlands. 

Pineywoods 

vegetational area. May 

also be associated with 

the Gulf Prairies and 

Marshes vegetational 

areas, but this is not 

confirmed by historical 

or extant records. 

Plant prefers open 

canopy and at least 

some ground cover, and 

intermediate seral 

stages in community 

succession. (USFWS

1995)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

pine woodlands. 

1995 USFWS Texas trailing phlox 

recovery plan

Texas wild-rice 

(Zizania texana)

This plant grows in 

clear flowing spring-fed 

waters. (USFWS 2008)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

water bodies. 

2008 USFWS 5-Year Reviews of 

28 Southwestern Species

Tobusch 

fishhook cactus 

(Sclerocactus 

brevihamatus 

ssp. tobuschii)

The cacti occur in 

gravelly soils along 

rivers and plants are 

periodically disturbed 

by flooding. Severe 

floods will destroy 

plants but some 

disturbance appears to 

benefit the species 

because non-flooded 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

streams, rivers or other 

water bodies. 

USFWS 1987. Tobusch fishhook 

cactus recovery plan.

Available at:

http://ecos.fws.gov/docs/recovery_

plan/870318a.pdf

USFWS 2010. Tobusch Fishhook 

Cactus Completed 5-Year Review. 

Page 27. Available at:
144

Species Habitat Rationale Source 

areas become very 

grassy which tends to 

crowd out the cacti 

(USFWS 1987). 

However by the early 

1990s many new 

locations had been 

discovered, and the 

species was known 

from eight counties. 

Most sites were no 

longer in the floodplain, 

but found from lower 

slopes to ridge tops 

(USFWS 2010)

http://ecos.fws.gov/docs/five_year

_review/doc3073.pdf

Walker's 

manioc 

(Manihot 

walkerae)

An understory species 

that inhabits open 

brushlands in the Lower 

Rio Grande Valley of 

Texas and adjacent 

mexico (p. i). Most 

manihot species are 

found in relatively dry 

regions, and only a few 

are typically found in 

rain forest regimes. 

Those species found in 

rain forest are typically 

found in openings in the 

forest... these 

considerations lead us 

the hypothesis that most 

species are heliophiles 

capable of growth only 

when there is no 

shading, and that many 

of them are "weedy" 

types, capable of 

invasion into open areas 

(p. 6). (USFWS 2007)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

open brushlands. 

2007 USFWS Recovery Plan

White 

bladderpod 

(Lesquerella 

pallida)

The plant grows on 

openings in oak, 

hickory, and pine 

woods. It is limited to a 

part of the Piney Woods 

region on the Gulf 

The proposed dicamba 

DGA uses are not 

expected to overlap with 

forests. 

1992 USFWS White Bladderpod 

(Lesquerella padilla) recovery 

plan
145

Species Habitat Rationale Source 

Coastal Plain. (USFWS 

1992)

White irisette 

(Sisyrinchium 

dichotomum)

This rare herb is

typically found in open 

dry to mesic oakhickory forests on midelevation mountain 

slopes and on open, 

disturbed sites, such as 

woodland edges and 

roadsides. (USFWS 

1995)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

forests. 

1995 US FWS RECOVERY 

PLAN for White Irisette 

(Sisyrinchitan dichoixirun) 

Bicknell

White-haired 

goldenrod 

(Solidago 

albopilosa)

Grows in sandy soil 

behind the drip line of 

sandstone rock-shelters 

and on rock ledges. It is 

very rarely found in 

open sunlight and is 

never found in the 

darkest recesses of 

rock-shelters (p. i). 

(USFWS 1993)

The proposed dicamba 

DGA uses are not 

expected to overlap with 

sandstone rock shelters. 

1993 USFWS Recovery Plan

Zapata 

bladderpod 

(Lesquerella 

thamnophila)

Zapata bladderpod is 

known to occur on 

graveled to sandy-loam

upland terraces above 

the Rio Grande flood 

plain. The known 

populations of Zapata 

bladderpod are

associated with highly 

calcareous sandstones 

and clays, and occur 

within a community of 

shrub species. Zapata 

bladderpod occurs as an 

herbaceous component 

of an open 

Leucophyllum 

frutescens (cenizo) -

Acacia berlanderi

(guajillo) shrubland

alliance (Nature Serve 

2002) (Figure 4). Both

The proposed dicamba 

DGA uses are not 

expected to overlap with 

shrubland. 

2004 USFWS Zapata Bladderpod 

(Lesquerella thamnophilia) 

Recovery Plan
146

Species Habitat Rationale Source 

plant communities 

dominate upland 

habitats on shallow 

soils near the Rio 

Grande (Diamond et al. 

1987). These shrub 

lands are sparsely 

vegetated due to the 

shallow, fast-draining, 

highly erosional

soils and semi-arid 

climate. (USFWS 2004)
147

Appendix 3

Input parameters for TIM simulation for calculating mortality to Eskimo curlew exposed 

to dicamba

Parameter Value Comments

pesticide name dicamba none

crop name Corn, soybean and 

cotton

none

species name Eskimo curlew

Generic bird # (values of 1-30 are generic, 0 = 

custom) 0

Passerine ? (yes=1, no = 0) 0

nest type (0 =altricial, 1 = precocial) 1

Number of birds (trials) simulated 10,000

Flock size 50 Most recent estimate of population 

size

Random number seed (Enter 0 if user does not select a 

seed) 0

Turns QC reports on (1) or off (0) 0

Turns TIM executable call for user input on (1) or off 

(0) 0

Turns MCnest outputs on (1) or off (0) 0

Food switch 1

Drinking water puddle switch 1

Drinking water dew switch 1

Inhalation vapor switch 0

The maximum vapor concentration at 

saturation (calculated by STIR) is 

2.14e-3 mg/L. Since the available rat 

inhalation toxicity data did not 

establish an LC50 at a level that is 

orders of magnitude higher (i.e., 5.3 

mg/L, MRID 00263861), this route 

of exposure is not considered of 

toxicological concern.

Inhalation spray switch 1 This is automatically turned off by 

the model due to the crop height.

Dermal contact switch 1

Dermal spray switch 1 This is automatically turned off by 

the model due to the crop height.

Spray drift switch 0 Spray drift mitigations in place

Number of days simulated

3 Assume that while the birds are 

moving through the area during 

migration, they will stop and forage 

in an area for 3 d.

Number of applications 1 Assume that birds land in field on 

day of application

Rate of application #1 (lb a.i./A) 1.0 Proposed label

Interval between app1 and 2 (days) 0
148

Parameter Value Comments

Rate of application #2 (lb a.i./A) 0

Interval between app2 and 3 (days) 0

Rate of application #3 (lb a.i./A) 0

Interval between app3 and 4 (days) 0

Rate of application #4 (lb a.i./A) 0

Interval between app 4 and 5 (days) 0

Rate of application #5 (lb a.i./A) 0

Time of first application (hour) 8 Assume that application is made in 

the morning.

Application method (1 = Air, 2 = Ground Broadcast, 3 

= Ground Banded, 4 = Ground infurrow, 5 = 

Airblast)

2 Proposed label

droplet spectrum for air and ground, (1= very fine to 

fine, 2 = fine to medium, 3 = medium to coarse (air 

only), 4 = coarse to very coarse (air only))

1 Since spray drift switch is turned off, 

this parameter value does not impact 

the model’s results.

Spray height (m) 0.61 Assume 24” boom height.

Spray duration (min) 0.5 Default

Crop height (m)

0.127 Assumed height at time of 3rd

application (4 weeks after 

emergence).

Plant(crop) mass (kg/ha) 1 Default value. Not used because 

inhalation routes are turned off.

Crop type, (1= field, 2= orchard, 3= vineyard) 1

Fraction of edge habitat receiving drift 0

Fraction of organic carbon in soil 0.015 Default

Bulk density of soil (kg/L) 1.5 Default

Morning feeding start times: min and max 4 5

Default (Lebanon KS) Morning feeding end times: min and max 6 10

afternoon feeding start times: min and max 16 19

afternoon feeding end times: min and max 20 21

Proportion of daily feeding taking place in morning: 

min and max 0.4 0.6

Varying proportions of food 

distributed between morning and 

afternoon.

Gorging factor 3

Assume that birds gorge when they 

land. Factor of 3x normal feeding 

based on ECOFRAM 

recommendation.

Body weight (g): mean, sd, min, max 362, 36, 273, 454 Dunning 1984

feeding category: 

(1 = insectivore, 2 = herbivore, 3 = granivore, 4 = 

omnivore)

1

Fraction of each food item: insects, seeds, fruit, grass, 

broadleaf 1.0, 0, 0, 0, 0 Recovery plan
149

Parameter Value Comments

For juveniles: fraction of each food item: insects, 

seeds, fruit, grass, broadleaf 1.0, 0, 0, 0, 0

Note that although there are juvenile 

parameters included here, these 

values are not the focus of this report. 

The juvenile parameters are used by 

the MCnest model. 

Resident status (1=field, 0 = edge) 0

Frequency on field: mean, min, max 0.1, 0, 1

Mean frequency on field of species is 

unknown. Mean values of 10% and 

90% used to bound risk.

Fidelity factor (Q), (edge residents = 0.6, field 

residents = 0.8) 0.6 Default

Contaminated fraction of food 1.0, 1.0, 1.0, 1.0, 1.0

Food item half-lives (days) 8.5 8.5 8.5 8.5 8.5 Foliar dissipation half-life used for 

all food items.

Aerobic soil metabolism half-life (days) 18 Aerobic soil metabolism half-life. 

Stable to hydrolysis.

Koc (L/kg-oc) 13.4 MRID 42774101

Kow 0.71 Based on LogD

Henry’s law constant (atm/m3-mol) 1.17e-9

Solubility in water (mg/L) 6100 SANDZONE Safety Data Sheet (Nov 

1989)

Dislodgable foliar residue adjustment factor 0. 48 default

Dermal adsorption fraction 1 default

avian acute oral LD50 (mg a.i./kg-bw) 188 From bobwhite quail study.

Slope of avian oral LD50 4.5 No value is available. Assume 

default.

Avian acute inhalation LD50 (mg a.i./kg-bw) 0 Not available.

Rat inhalation LD50 (mg a.i./kg-bw) >594 Value converted from LC50 value. 

(MRID 00263861)

Rat acute oral LD50 (mg a.i./kg-bw) 2740 MRID 00078444

Respiratory physiology adjustment factor 3.2 Default for bird body weight.

Chemical specific avian dermal LD50 (enter 0 if no 

value is available)

0 None

Food matrix adjustment factor 1 No data are available. Assume 

default.

Fraction of pesticide retained from one hour to the 

next

0.99 MRID 43245202

ratio of juvenile to adult toxicity 1 No data are available. Assume 

default.
150

Appendix 4

Bird Species County Land cover Information

Eskimo Curlew
151
152

Appendix 5

Critical Habitat Designations and PCE Descriptions
153

Summary of 14 Listed Species Identified as being on Agricultural Fields with and without Critical Habitat 

Designations for AL, GA, KY, MI, NC, SC and TX Assessed for dicamba DGA salt

Species Name Primary Constituent Elements (PCE) Source

Species with Critical Habitat Designations (5 Species)3

Houston toad (Bufo 

houstonensis)

Bastrop and Burleson Counties, Texas. Primary Constituent 

Elements not identified.

http://ecos.fws.gov/specie

sProfile/profile/speciesPr

ofile.action?spcode=D004

#crithab

http://ecos.fws.gov/docs/f

ederal_register/fr179.pdf

Indiana bat (Myotis 

sodalis)

Critical habitat designations are either mines or caves. http://ecos.fws.gov/docs/f

ederal_register/fr161.pdf

Louisiana black 

bear (Ursus 

americanus luteolus)

PCE: Relatively inaccessible terrain, thick understory 

vegetation and abundant food sources in the form of shrubs 

or tree borne soft or hard mast. Currently found in 

bottomland hardwood forest communities. Home range very 

dependent on forest cover.

http://www.gpo.gov/fdsys

/pkg/FR-2009-03-

10/pdf/E9-

4536.pdf#page=1

Virginia big-eared 

bat (Corynorhinus 

(=Plecotus) 

townsendii 

virginianus)

Critical habitat designations are caves. http://ecos.fws.gov/specie

sProfile/profile/speciesPr

ofile.action?spcode=A080

#crithab

http://ecos.fws.gov/docs/f

ederal_register/fr366.pdf

Whooping crane 

(Grus americana)

PCE: All areas proposed in this rule would provide food, 

water, and other nutritional or physiological needs of the 

whooping crane during spring or fall migration. 

Consumption of some cereal crops in adjacent croplands 

during migration period. Direct relatable resources to 

agricultural field possibly treated with 2,4-D choline.

http://ecos.fws.gov/docs/f

ederal_register/fr237.pdf

Species without critical habitat designations (10 species)

American burying 

beetle (Nicrophorus 

americanus)

None http://ecos.fws.gov/specie

sProfile/profile/speciesPr

ofile.action?spcode=I028

#crithab

Attwater's greater 

prairie-chicken 

(Tympanuchus 

cupido attwateri)

None http://ecos.fws.gov/specie

sProfile/profile/speciesPr

ofile.action?spcode=B00

O#crithab

Eastern indigo 

snake (Drymarchon 

corais couperi)

None http://ecos.fws.gov/specie

sProfile/profile/speciesPr

ofile.action?spcode=C026

#crithab

Eskimo curlew 

(Numenius borealis)

None http://ecos.fws.gov/specie

sProfile/profile/speciesPr

ofile.action?spcode=B01

A#crithab

 3 Critical habitat designation status determined using U.S. Fish & Wildlife Service’s Environmental Conservation 

Online System (ECOS) species profiles.
154

Gopher tortoise 

(Gopherus 

polyphemus)

None http://ecos.fws.gov/specie

sProfile/profile/speciesPr

ofile.action?spcode=C044

#crithab

Gulf Coast 

jaguarundi 

(Herpailurus 

(=Felis) 

yagouaroundi 

cacomitli)

None http://ecos.fws.gov/specie

sProfile/profile/speciesPr

ofile.action?spcode=A05

H#crithab

Lesser prairiechicken 

(Tympanuchus 

pallidicinctus)

None http://ecos.fws.gov/specie

sProfile/profile/speciesPr

ofile.action?spcode=B0A

Z#crithab

Ocelot (Leopardus 

(Felis) pardalis)

None http://ecos.fws.gov/specie

sProfile/profile/speciesPr

ofile.action?spcode=A084

#crithab

Red wolf (Canis 

rufus)

None http://ecos.fws.gov/specie

sProfile/profile/speciesPr

ofile.action?spcode=A00

F#crithab

Summary of 292 Listed Species Identified as being off Agricultural Fields with and without 

Critical Habitat Designations for AL, GA, KY, MI, NC, SC and TX Assessed for dicamba DGA 

salt

Critical Habitat Designation Species Name

Species with Critical Habitat 

Designations (113 Species)4

[Unnamed] ground beetle (Rhadine exilis)

[Unnamed] ground beetle (Rhadine infernalis)

Alabama beach mouse (Peromyscus polionotus ammobates)

Alabama cavefish (Speoplatyrhinus poulsoni)

Alabama moccasinshell (Medionidus acutissimus)

Alabama pearlshell (Margaritifera marrianae)

Alabama sturgeon (Scaphirhynchus suttkusi)

Altamaha Spinymussel (Elliptio spinosa)

Amber darter (Percina antesella)

Appalachian elktoe (Alasmidonta raveneliana)

Arkansas River shiner (Notropis girardi)

Austin blind salamander (Eurycea waterlooensis)

Braken Bat Cave Meshweaver (Cicurina venii)

Braun's rock-cress (Arabis perstellata)

Cahaba shiner (Notropis cahabae)

Canada lynx (Lynx canadensis)

Cape Fear shiner (Notropis mekistocholas)

Carolina heelsplitter (Lasmigona decorata)

Chipola slabshell (Elliptio chipolaensis)

 4 Critical habitat designation status determined using U.S. Fish & Wildlife Service’s Environmental Conservation 

Online System (ECOS) species profiles. 
155

Choctaw bean (Villosa choctawensis)

Cokendolpher Cave Harvestman (Texella cokendolpheri)

Comal Springs dryopid beetle (Stygoparnus comalensis)

Comal Springs riffle beetle (Heterelmis comalensis)

Conasauga logperch (Percina jenkinsi)

Coosa moccasinshell (Medionidus parvulus)

Cumberland darter (Etheostoma susanae)

Cumberland elktoe (Alasmidonta atropurpurea)

Cumberlandian combshell (Epioblasma brevidens)

Dark pigtoe (Pleurobema furvum)

Devils River minnow (Dionda diaboli)

Diamond Y Spring snail (Pseudotryonia adamantina)

Diminutive Amphipod (Gammarus hyalleloides)

Fat three-ridge (mussel) (Amblema neislerii)

Finelined pocketbook (Lampsilis altilis)

Fleshy-fruit gladecress (Leavenworthia crassa)

Fluted kidneyshell (Ptychobranchus subtentum)

Fountain darter (Etheostoma fonticola)

Frosted Flatwoods salamander (Ambystoma cingulatum)

Fuzzy pigtoe (Pleurobema strodeanum)

Georgetown salamander (Eurycea naufragia)

Georgia pigtoe (Pleurobema hanleyianum)

Golden sedge (Carex lutea)

Goldline darter (Percina aurolineata)

Gonzales springsnail (Tryonia circumstriata)

Government Canyon Bat Cave Meshweaver (Cicurina vespera)

Government Canyon Bat Cave Spider (Neoleptoneta microps)

Green sea turtle (Chelonia mydas)

Gulf moccasinshell (Medionidus penicillatus)

Gulf sturgeon (Acipenser oxyrinchus desotoi)

Hawksbill sea turtle (Eretmochelys imbricata)

Helotes mold beetle (Batrisodes venyivi)

Hine's emerald dragonfly (Somatochlora hineana)

Interrupted (=Georgia) Rocksnail (Leptoxis foremani)

Jollyville Plateau salamander (Eurycea tonkawae)

Karner blue butterfly (Lycaeides melissa samuelisY)

Kentucky cave shrimp (Palaemonias ganteri)

Kentucky glade cress (Leavenworthia exigua laciniata)

Leatherback sea turtle (Dermochelys coriacea)

Leon Springs pupfish (Cyprinodon bovinus)

Loggerhead sea turtle (Caretta caretta)

Madla's Cave Meshweaver (Cicurina madla)

Mexican spotted owl (Strix occidentalis lucida)

Mountain golden heather (Hudsonia montana)

Narrow pigtoe (Fusconaia escambia)

Neches River rose-mallow (Hibiscus dasycalyx)
156

North Atlantic Right Whale (Eubalaena glacialis)

Ochlockonee moccasinshell (Medionidus simpsonianus)

Oval pigtoe (Pleurobema pyriforme pyriforme)

Ovate clubshell (Pleurobema perovatum)

Oyster mussel (Epioblasma capsaeformis)

Peck's cave amphipod (Stygobromus (=Stygonectes) pecki)

Pecos (=puzzle, =paradox) sunflower (Helianthus paradoxus)

Pecos assiminea snail (Assiminea pecos)

Perdido Key beach mouse (Peromyscus polionotus trissyllepsis)

Phantom springsnail (Pyrgulopsis texana)

Phantom tryonia (Tryonia cheatumi)

Piping Plover (Charadrius melodus)

Purple bankclimber (mussel) (Elliptoideus sloatianus)

Pygmy Sculpin (Cottus paulus (=pygmaeus))

Rabbitsfoot (Quadrula cylindrica cylindrica)

Reticulated flatwoods salamander (Ambystoma bishopi)

Robber Baron Cave Meshweaver (Cicurina baronia)

Rough hornsnail (Pleurocera foremani)

Round Ebonyshell (Fusconaia rotulata)

Rush Darter (Etheostoma phytophilum)

Salado salamander (Eurycea chisholmensis)

San Marcos gambusia (Gambusia georgei)

San Marcos salamander (Eurycea nana)

Sharpnose Shiner (Notropis oxyrhynchus)

Shinyrayed pocketbook (Lampsilis subangulata)

Short's bladderpod (Physaria globosa)

Slabside Pearlymussel (Pleuronaia dolabelloides)

Slackwater darter (Etheostoma boschungi)

Smalleye Shiner (Notropis buccula)

Snail darter (Percina tanasi)

Southern acornshell (Epioblasma othcaloogensis)

Southern clubshell (Pleurobema decisum)

Southern kidneyshell (Ptychobranchus jonesi)

Southern pigtoe (Pleurobema georgianum)

Southwestern willow flycatcher (Empidonax traillii extimus)

Spotfin Chub (Erimonax monachus)

Spruce-fir moss spider (Microhexura montivaga)

Sunfish, spring pygmy (Elassoma alabamae)

Tapered pigtoe (Fusconaia burkei)

Texas Golden Gladecress (Leavenworthia texana)

Texas wild-rice (Zizania texana)

Triangular Kidneyshell (Ptychobranchus greenii)

Upland combshell (Epioblasma metastriata)

Vermilion darter (Etheostoma chermocki)

Waccamaw silverside (Menidia extensa)

West Indian Manatee (Trichechus manatus)
157

Whorled Sunflower (Helianthus verticillatus)

Zapata bladderpod (Lesquerella thamnophila)

Species without Critical Habitat 

Designations (179 species)

Alabama (=inflated) heelsplitter (Potamilus inflatus)

Alabama canebrake pitcher-plant (Sarracenia rubra 

alabamensis)

Alabama cave shrimp (Palaemonias alabamae)

Alabama lampmussel (Lampsilis virescens)

Alabama leather flower (Clematis socialis)

Alabama red-belly turtle (Pseudemys alabamensis)

Alabama streak-sorus fern (Thelypteris pilosa var. 

alabamensis)

American chaffseed (Schwalbea americana)

American hart's-tongue fern (Asplenium scolopendrium var. 

americanum)

Anthony's riversnail (Athearnia anthonyi)

Armored snail (Pyrgulopsis (=Marstonia) pachyta)

Ashy dogweed (Thymophylla tephroleuca)

Bachman's warbler (=wood) (Vermivora bachmanii)

Barton Springs salamander (Eurycea sosorum)

Bee Creek Cave harvestman (Texella reddelli)

Big Bend gambusia (Gambusia gaigei)

Black lace cactus (Echinocereus reichenbachii var. albertii)

Black spored quillwort (Isoetes melanospora)

Black-capped Vireo (Vireo atricapilla)

Blackside dace (Phoxinus cumberlandensis)

Blue Ridge goldenrod (Solidago spithamaea)

Blue shiner (Cyprinella caerulea)

Bone Cave harvestman (Texella reyesi)

Boulder darter (Etheostoma wapiti)

Bunched arrowhead (Sagittaria fasciculata)

Bunched cory cactus (Coryphantha ramillosa)

Canby's dropwort (Oxypolis canbyi)

Carolina northern flying squirrel (Glaucomys sabrinus 

coloratus)

Cherokee darter (Etheostoma scotti)

Chisos Mountain hedgehog Cactus (Echinocereus chisoensis 

var. chisoensis)

Clear Creek gambusia (Gambusia heterochir)

Clubshell (Pleurobema clava)

Coffin Cave mold beetle (Batrisodes texanus)

Comanche Springs pupfish (Cyprinodon elegans)

Cooley's meadowrue (Thalictrum cooleyi)

Copperbelly water snake (Nerodia erythrogaster neglecta)

Cracking pearlymussel (Hemistena lata)

Cumberland bean (pearlymussel) (Villosa trabalis)
158

Cumberland monkeyface (pearlymussel) (Quadrula 

intermedia)

Cumberland rosemary (Conradina verticillata)

Cumberland sandwort (Arenaria cumberlandensis)

Cylindrical lioplax (snail) (Lioplax cyclostomaformis)

Davis' green pitaya (Echinocereus viridiflorus var. davisii)

Dromedary pearlymussel (Dromus dromas)

Duskytail darter (Etheostoma percnurum)

Dwarf lake iris (Iris lacustris)

Dwarf wedgemussel (Alasmidonta heterodon)

Dwarf-flowered heartleaf (Hexastylis naniflora)

Eastern prairie fringed orchid (Platanthera leucophaea)

Etowah darter (Etheostoma etowahae)

False killer whale (Pseudorca crassidens)

Fanshell (Cyprogenia stegaria)

Fat pocketbook (Potamilus capax)

Finback whale (Balaenoptera physalus)

Finerayed pigtoe (Fusconaia cuneolus)

Flat pebblesnail (Lepyrium showalteri)

Flat pigtoe (Pleurobema marshalli)

Flattened musk turtle (Sternotherus depressus)

Florida torreya (Torreya taxifolia)

Fringed campion (Silene polypetala)

Gentian pinkroot (Spigelia gentianoides)

Golden-cheeked warbler (=wood) (Dendroica chrysoparia)

Gray bat (Myotis grisescens)

Green pitcher-plant (Sarracenia oreophila)

Hairy rattleweed (Baptisia arachnifera)

Harperella (Ptilimnium nodosum)

Heavy pigtoe (Pleurobema taitianum)

Heller's blazingstar (Liatris helleri)

Hinckley oak (Quercus hinckleyi)

Houghton's goldenrod (Solidago houghtonii)

Humpback whale (Megaptera novaeangliae)

Hungerford's crawling water Beetle (Brychius hungerfordi)

James spinymussel (Pleurobema collina)

Johnston's frankeni (Frankenia johnstonii)

Kemp's ridley sea turtle (Lepidochelys kempii)

Kirtland's Warbler (Setophaga kirtlandii)

Kral's water-plantain (Sagittaria secundifolia)

Kretschmarr Cave mold beetle (Texamaurops reddelli)

Lacy elimia (snail) (Elimia crenatella)

Lakeside daisy (Hymenoxys herbacea)

Large-flowered skullcap (Scutellaria montana)

Large-fruited sand-verbena (Abronia macrocarpa)

Leafy prairie-clover (Dalea foliosa)
159

Least tern (Sterna antillarum)

Little Aguja (=Creek) Pondweed (Potamogeton clystocarpus)

Little amphianthus (Amphianthus pusillus)

Littlewing pearlymussel (Pegias fabula)

Lloyd's Mariposa cactus (Echinomastus mariposensis)

Louisiana quillwort (Isoetes louisianensis)

Lyrate bladderpod (Lesquerella lyrata)

Mat-forming quillwort (Isoetes tegetiformans)

Mexican long-nosed bat (Leptonycteris nivalis)

Miccosukee gooseberry (Ribes echinellum)

Michaux's sumac (Rhus michauxii)

Michigan monkey-flower (Mimulus michiganensis)

Mitchell's satyr Butterfly (Neonympha mitchellii mitchellii)

Mohr's Barbara button (Marshallia mohrii)

Morefield's leather flower (Clematis morefieldii)

Mountain sweet pitcher-plant (Sarracenia rubra ssp. Jonesii)

Navasota ladies'-tresses (Spiranthes parksii)

Nellie cory cactus (Coryphantha minima)

No common name (Geocarpon minimum)

Noonday globe (Patera clarki nantahala)

Northern aplomado falcon (Falco femoralis septentrionalis)

Northern riffleshell (Epioblasma torulosa rangiana)

Orangefoot pimpleback (pearlymussel) (Plethobasus 

cooperianus)

Orangenacre mucket (Lampsilis perovalis)

Painted rocksnail (Leptoxis taeniata)

Pale lilliput (pearlymussel) (Toxolasma cylindrellus)

Palezone shiner (Notropis albizonatus)

Pallid sturgeon (Scaphirhynchus albus)

Pecos gambusia (Gambusia nobilis)

Persistent trillium (Trillium persistens)

Pink mucket (pearlymussel) (Lampsilis abrupta)

Pitcher's thistle (Cirsium pitcheri)

Plicate rocksnail (Leptoxis plicata)

Pondberry (Lindera melissifolia)

Price's potato-bean (Apios priceana)

purple cat's paw (=purple cat's paw pearlymussel) (Epioblasma 

obliquata obliquata)

Rayed Bean (Villosa fabalis)

Red Hills salamander (Phaeognathus hubrichti)

Red-cockaded woodpecker (Picoides borealis)

Relict darter (Etheostoma chienense)

Relict trillium (Trillium reliquum)

Ring pink (mussel) (Obovaria retusa)

Roan Mountain bluet (Hedyotis purpurea var. montana)

Rock gnome lichen (Gymnoderma lineare)
160

Roseate tern (Sterna dougallii dougallii)

Rough pigtoe (Pleurobema plenum)

Rough-leaved loosestrife (Lysimachia asperulaefolia)

Round rocksnail (Leptoxis ampla)

Running buffalo clover (Trifolium stoloniferum)

Saint Francis' satyr butterfly (Neonympha mitchellii francisci)

Schweinitz's sunflower (Helianthus schweinitzii)

Seabeach amaranth (Amaranthus pumilus)

Sensitive joint-vetch (Aeschynomene virginica)

Sheepnose Mussel (Plethobasus cyphyus)

Shiny pigtoe (Fusconaia cor)

Shortnose sturgeon (Acipenser brevirostrum)

Short's goldenrod (Solidago shortii)

Slender campeloma (Campeloma decampi)

Slender rush-pea (Hoffmannseggia tenella)

Small whorled pogonia (Isotria medeoloides)

Small-anthered bittercress (Cardamine micranthera)

Smalltooth sawfish (Pristis pectinata)

Smooth coneflower (Echinacea laevigata)

Sneed pincushion cactus (Coryphantha sneedii var. sneedii)

Snuffbox mussel (Epioblasma triquetra)

South Texas ambrosia (Ambrosia cheiranthifolia)

Southern combshell (Epioblasma penita)

Southern sandshell (Hamiota (=Lampsilis) australis)

Spectaclecase (mussel) (Cumberlandia monodonta)

Sperm whale (Physeter catodon (=macrocephalus))

Spreading avens (Geum radiatum)

Star cactus (Astrophytum asterias)

Stirrupshell (Quadrula stapes)

Swamp pink (Helonias bullata)

Tar River spinymussel (Elliptio steinstansana)

Tennessee yellow-eyed grass (Xyris tennesseensis)

Terlingua Creek cat's-eye (Cryptantha crassipes)

Texas ayenia (Ayenia limitaris)

Texas blind salamander (Typhlomolge rathbuni)

Texas poppy-mallow (Callirhoe scabriuscula)

Texas prairie dawn-flower (Hymenoxys texana)

Texas snowbells (Styrax texanus)

Texas trailing phlox (Phlox nivalis ssp. texensis)

Tobusch fishhook cactus (Sclerocactus brevihamatus ssp. 

tobuschii)

Tooth Cave ground beetle (Rhadine persephone)

Tooth Cave pseudoscorpion (Tartarocreagris texana)

Tooth Cave Spider (Leptoneta myopica)

Tulotoma snail (Tulotoma magnifica)

Virginia spiraea (Spiraea virginiana)
161

Walker's manioc (Manihot walkerae)

Watercress darter (Etheostoma nuchale)

White bladderpod (Lesquerella pallida)

White irisette (Sisyrinchium dichotomum)

White wartyback (pearlymussel) (Plethobasus cicatricosus)

White-haired goldenrod (Solidago albopilosa)

Wood stork (Mycteria americana)

Yellow blossom (pearlymussel) (Epioblasma florentina 

florentina)
162

Appendix 6

U.S. Fisk and Wildlife Service Concurrence Memo for Eskimo Curlew Effects Determination
163

From: Swem, Ted [mailto:ted_swem@fws.gov] 

Sent: Monday, May 11, 2015 5:40 PM

To: Wagman, Michael

Subject: Re: Eskimo Curlew (Dicamba ESA assessment)

Dear Mr. Wagman

Regrettably, we do concur with your determination. Although we prefer to hold out hope and 

have not removed the Eskimo Curlew from the list of Threatened and Endangered Species, we 

consider it to be "presumed extinct." We believe therefore that there are none left to encounter 

pesticides applied anywhere, and thus agree that the effects of the proposed action are 

discountable.

Thank you for checking in, though.

Ted Swem

On Mon, May 11, 2015 at 1:33 PM, Wagman, Michael <Wagman.Michael@epa.gov> wrote:

Ted Swem, Chief, 

Endangered Species Branch, 

Fairbanks Fish and Wildlife Field Office,

US Fish and Wildlife Service (907) 456-0441 

Dear Mr. Swem

The USEPA Office of Pesticide Programs is in the process of making an effects determination 

for the registration of the herbicide dicamba diglycolamine (DGA) salt on cotton and soybean 

fields in Texas, Nebraska and Oklahoma. Use of the pesticide will be limited to ground spray 

application using a formulation and specific spray equipment in combination to spray drift 

setbacks that result in pesticide application areas of concern limited to only the actual on-field 

treatment site (the targeted cotton or soybean field itself).

Our review of available species location information suggests a potential for a migrant Eskimo 

curlew (Numenius borealis) passing through Texas, Nebraska and Oklahoma to encounter a 

treated field with dicamba DGA residues. Our analysis indicates that if such an encounter 

occurred, the residue levels that would trigger a concern for adverse effects to the 

bird. However, in reviewing the available information on the status of the Eskimo curlew1

, we 

have determined that individuals of the species are extremely rare. This rarity of individuals 
164

indicates to us that the chance of an individual curlew to encounter a dicamba DGA treated 

cotton or soybean field would be extremely unlikely to occur. Therefore any effects of dicamba 

DGA salt to an Eskimo curlew would be extremely unlikely to occur.

An effect that is extremely unlikely to occur would be considered discountable in regards to an 

effects determination and would be consistent with a determination of Not Likely to Adversely 

Affect. We therefore have determined that the proposed use of dicamba DGA salt on cotton and 

soybeans in Texas, Nebraska and Oklahoma will Not Likely to Adversely Affect individual 

Eskimo curlews.

Does the United States Fish and Wildlife Service concur with our effects determination?

Sincerely, 

Michael Wagman

Biologist, Environmental Risk Branch VI

Environmental Fate and Effects Division

Office of Pesticide Programs

United States Environmental protection Agency

703-347-0198

1 Eskimo Curlew (Numenius borealis) 5-Year Review: Summary and Evaluation, August 31, 

2011, U.S. Fish and Wildlife Service, Fairbanks Fish and Wildlife Field Office, Fairbanks 

Alaska