Viability Analyses for Vascular Plant Species within 

Prescott National Forest, Arizona

Dr. Marc Baker 

Compiled January 2011 with 

January 2014 updates 

for

Forest Plan Revision 

Environmental Impact Statements 
2

Part 1. Description of Ecological Context (Adapted from: Ecological 

Sustainability Report, Prescott National Forest, Prescott, Arizona, April 

2009) 

Description of the Planning Unit 

Prescott National Forest (PNF) includes mostly mountains and associated 

grassy valleys of central Arizona that lie between the forested plateaus to the 

north and the arid desert region to the south. Elevations range between 3,000 

feet above sea level along the lower Verde Valley to 7,979 feet at the top of 

Mount Union, the highest natural feature on the Forest. 

Roughly half of the PNF occurs west of the city of Prescott, Arizona, in the 

Juniper, Santa Maria, Sierra Prieta, and Bradshaw Mountains. The other half of 

the PNF lies east of Prescott and takes in the terrain of Mingus Mountain, the 

Black Hills, and Black Mesa. 

The rugged topography of the PNF provides important watersheds for 

both the Verde and Colorado Rivers. Within these watersheds are many 

important continuously or seasonally flowing stream courses and drainages. A 

portion of the Verde River has been designated as part of the National Wild and 

Scenic Rivers System. 

Vegetation within PNF is complex and diverse: Sonoran Desert, 

dominated by saguaro cacti and paloverde trees, occurs to the south of 

Bradshaw Mountains; and cool mountain forests with conifer and aspen trees 

occur within as few as 10 miles upslope from the desert . In between, there are a 

variety of plant and animal habitats including grasslands, hot steppe shrub, 

chaparral, pinyon-juniper woodlands, and ponderosa pine forests. 

There are eight designated wilderness areas comprising more than 

104,000 acres, located entirely or partially within the PNF. Portions of the PNF 

are located less than 90 miles from the Phoenix metropolitan area – a source of 

regional haze and wind-borne pollutants. 

The degree to which the PNF can provide for a diversity of ecosystems 

and species relative to the surrounding area is known as ‘ecological niche’. The 

ecological niche of the PNF can be defined by its location within the broader 

landscape and by examining the various ecological communities and processes 

that are represented within and outside the boundaries of the planning unit. 

Using the national ecological hierarchy, ecosystems can be mapped and 

described as a series of nested units based on similar environmental factors. 

Ecoregions are areas of regional extent that share common climatic and 

vegetation characteristics. Areas within an ecoregion are sub-divided into 

provinces. Provinces are controlled primarily by continental weather patterns 

such as length of dry season and duration of cold temperatures. Provinces are 

also characterized by similar soil orders and dominant potential natural 

vegetation. Figure 2 shows the location of the PNF in relation to the ecological 

provinces identified for the state of Arizona. 

 
3

Figure 2. The ecological provinces of Arizona 

 

Areas within a province are sub-divided into sections. Sections describe 

broad areas of similar sub-regional climate, geologic origin, composition, and 

development, local topography, and drainage networks. Figure 3 identifies the 

nine ecological sections nested within the four provinces of Arizona. For 

example, the Colorado Plateau Semi-Desert province includes the Grand 

Canyon, Painted Desert, Navajo Canyonlands, and Tonto Transition sections. 

As shown in figure 3, almost all PNF lands (92 percent) are found in the Tonto 

Transition section of the Colorado Plateau Semi-Desert province. The remaining 

portion of the PNF (eight percent) is shared between the Mojave Desert and the 

White Mountains-San Francisco Peaks-Mongollon Rim ecological sections. 

This means that the primary niche of the PNF is providing sustainable 

conditions for the ecological communities and processes that represent the Tonto 

Transition and secondarily protecting the additional ecosystem diversity within 

the PNF as represented by the other two ecological sections. 

 
4

Figure 3. Ecological sections associated with 

the PNF 

Ecological Sections		

The following paragraphs characterize the three ecological sections found 

on the PNF and surrounding landscapes and are summarized in Table 1 below. 

Table 1. Proportion of PNF lands within the ecological sections of central 

Arizona. 

Ecological Section Name Section 

Total 

Section 

Acres 

Off-PNF 

Acres PNF Acres PNF 

Percent 

Tonto Transition 313C 7,555,169 6,402,655 1,152,514 15.3 

White Mountains-San 

Francisco Peaks-Mogollon Rim M313A 13,475,096 13,405,710 69,386 0.5 

Mojave Desert 322A 33,376,908 33,342,889 34,019 0.1 

Grand Totals: 54,407,173 53,151,254 1,255,919 2.3 

 
5

Tonto Transition Section (describes 92% of PNF)  

Geomorphology. The Tonto Transition section is located in the highlands of 

central Arizona below the Colorado Plateau and above the basins of the Sonoran 

Desert. Volcanic activity and sedimentary deposition were major geomorphic 

processes. Lava flows, plugs, dikes, and relatively flat sedimentary deposits 

resulted. Major landforms are mountains, hills, scarps, and some plains. Major 

landform features include the Mazatzal Mountains, Black Hills, Aquarius 

Mountains, Bradshaw Mountains, and the Superstition Mountains. Elevation 

ranges from 3,000 to 7,400 ft (915 to 2,255 m). 

 

Climate. Precipitation ranges from 10 to 25 in (250 to 635 mm) annually, with 

more than half of the precipitation falling during the winter. Winters are mild 

below about 6,800 ft (2,075 m) and cold at higher elevations. The growing 

season lasts 70 to 170 days. 

 

Vegetation. Vegetation consists of interior chaparral (mix of deciduous and 

evergreen shrubs) on coarse igneous parent materials and steep slopes. There 

are pinyon-juniper woodlands on elevations higher than about 4,200 ft (1,280 m); 

ponderosa pine occurs in frigid and limited mesic soil temperature regimes at 

higher elevations. Low elevation vegetation consists of semi-arid grasslands and 

desert shrub-scrub communities. 

 

Disturbances. The natural fire frequency is highly variable, ranging from 2 to 

100 years, depending on aspect, elevation, soil moisture, and plant composition. 

Flash floods and droughts are common. 

White Mountain‐San Francisco Peaks‐Mogollon Rim Section (describes 5%

of PNF)  

Geomorphology. Located on the Colorado Plateau, this section is in central and 

eastern-central Arizona and west-central New Mexico. Geomorphic processes 

active in this section involve recent volcanism, including basaltic lava flows, 

cinder cone eruptions, and volcanic ash. Major landforms include mountains, 

plains, plateaus, and hills. Major landform features include the San Francisco 

Mountains, White Mountains, and Jemez and Mogollon Mountains. Elevation 

ranges from 6,000 to over 12,600 ft (1,820 to 3,860 m). 

 

Climate. Precipitation ranges from 20 to over 32 in (500 to over 800 mm) 

annually, with more than half of the precipitation falling during the winter. The 

growing season ranges from less than 50 to 110 days, and winters are cold. 

 

Vegetation. Plant communities vary over a soil temperature and moisture 
6

gradient with ponderosa pine and Gambel’s oaks on the relatively warm and dry 

sites; white fir and Douglas-fir forests on cool, moist sites; and Engelmann 

spruce and corkbark fir on the coldest, wettest sites. 

Disturbances. Natural fires occurred in ponderosa pine about every 3 to 10 

years, but have mostly been prevented during the 20

th

 century. This has led to a 

higher canopy cover and increased fuel loads, resulting in a less resilient 

ecosystem and increased hazard of wildfire. 

 

Mohave Desert Section (describes 3% of PNF)  

Geomorphology. This area comprises widely separated short ranges in desert 

plains located in Nevada, Utah, California, and in a small portion of westnorthwest Arizona. It contains isolated mountains, plateaus, alluvial fans, playas, 

basins, and dunes. Elevation ranges from 300 ft below sea level (Death Valley) 

to 11,000 ft above sea level (-91 to 3,344 m). 

 

Climate. Precipitation ranges from 3 to 10 in (80 to 250 mm). It mostly occurs as 

scattered high intensity storms of short duration. The growing season lasts 200 to 

300 days. 

 

Vegetation. Plant communities include creosote bush, blackbush, greasewood 

and saltbush on basins, plains, and hills; Joshua tree-dominated communities 

occur on plains and hills; and basin sagebrush, western juniper and pinyon pine 

communities occur on mountains. 

 

Disturbances. Areas with less than about 8 in (200 mm) of rainfall rarely support 

enough vegetation to carry a fire. Fire occurrence in areas receiving more than 

about 8 in (200 mm) has been influenced by introduced grasses. Fires are 

variable in frequency and intensity. Flash floods are commonly associated with 

the irregular occurrence of precipitation events. Table 1 displays the relationship 

of the PNF to the three ecological sections found in central Arizona. Overall, the 

sections total nearly 54.4 million acres (column three). The PNF occupies only 2 

percent of these three sections as presented in column six. 

Potential Natural Vegetation Types (PNVT)		

The sustainability of vegetation and soil resources was assessed by 

evaluating ecosystem characteristics within the above-mentioned ecological 

sections using potential natural vegetation types (PNVTs). PNVTs are coarsescale groupings of non-contiguous land that share similar aspect, elevation, 

vegetation, soil parent material, and historic disturbances such as fire, frost and 

drought cycles, and insect and disease outbreaks at a landscape scale. 
7

PNVTs represent the vegetation type and characteristics that would occur 

when natural disturbance regimes and biological processes prevail. It is 

important not to confuse PNVTs with existing vegetation types. The PNVT 

classifications weredeveloped from data available in the Terrestrial Ecosystem 

Survey of the Prescott NF (Robertson et al., 2000) and from information on 

vegetation dynamics and natural variability compiled by The Nature 

Conservancy1 and the Landscape Fire and Resource Management Planning 

Tools Project2 (commonly called LANDFIRE). 

Initial identification and classification of PNVTs resulted in 13 categories 

as reported in the Prescott NF Ecological Sustainability Report (Forest Service, 

2009). Additional data gathering and assessment since 2009 resulted in a 

refinement of the PNVT classification for the Prescott NF. Based on updated 

midscale vegetation inventory, field visits, data review, and bio-physical model 

fitting, the number of PNVTs identified on the Prescott NF was adjusted from 13 

to 10. Table 2 lists these 10 PNVTs and their proportional area. 

 

Refinements in the identification and classification of PNVTs included: 

 The Colorado Plateau Grassland PNVT also known as Colorado 

Plateau/Great Basin Grassland3 was shortened in name to Great Basin 

Grassland PNVT to acknowledge the fact that the Prescott NF does not 

reside on the Colorado Plateau. The Riparian Forest PNVT4 was renamed 

Riparian Gallery Forest PNVT in recognition of the long and narrow patterns 

that this PNVT forms along perennial and intermittent streams found on the 

Prescott NF. 

 The Mixed-Conifer with Frequent Fire PNVT (6,600 acres) was combined with 

the Ponderosa Pine Forest PNVT because they are described by the same 

biophysical setting model (e.g., vegetation structure and disturbance regime) 

developed by the Nature Conservancy5. The Ponderosa Pine Forest PNVT 

was later renamed as Ponderosa Pine-Gambel Oak PNVT. 

 The Mixed-Conifer with Aspen PNVT (80 acres) was determined to be a misidentification and the acres were added to the Ponderosa Pine-Gambel Oak 

PNVT. 

 

1 http://azconservation.org/downloads/category/southwest_regional/

2 www.landfire.gov

3 LANDFIRE biopysical setting model #1511350 “Inter-Mountain Basins Semi-Desert 

Grassland” 

4 LANDFIRE biophysical setting model #1511552 “North American Warm Desert Riparian 

Systems” 

5 TNC biophysical setting model “Ponderosa Pine/Bunchgrass” 
8

 The Madrean Encinal Woodland PNVT (5,500 acres) map units were grouped 

with adjoining PNVT units because of concerns about their identification. Most 

of the indicator species describing this PNVT, with the exception of the 

Mexican pines, were observed during field visits to the small and scattered 

map units assigned to this PNVT. These units were found to be interspersed 

with Interior Chaparral and Ponderosa Pine-Evergreen Oak PNVTs, 

suggesting the possibility that multiple fire disturbance regimes existing in 

close proximity to one another could account for the observed variations in 

vegetation composition and structure. There is uncertainty in how much the 

observed vegetation structure may reflect recent land use and/or disturbance 

history versus the presence of a distinct PNVT. Until additional information is 

available to address the uncertainty associated with identification of the 

Madrean Encinal Woodland PNVT, it was decided to manage the vegetation 

of these map units based on their adjoining PNVT. 

Table 2. Potential Natural Vegetation Types (PNVTs) of the Prescott NF 

PNVT Name 

Prescott National Forest 

Acres Percent

Semi-Desert Grassland 125,712 10 %

Great Basin Grassland 38,389 3 %

Juniper Grassland 137,274 11 %

Piñon-Juniper Evergreen Shrub 463,296 37 %

Interior Chaparral 315,445 25 %

Ponderosa Pine-Evergreen Oak 63,539 5 %

Ponderosa Pine-Gambel Oak 49,052 4 %

Piñon-Juniper Woodland 36,263 3 % 

Desert Communities 5,919 < 1 %

Riparian Gallery Forest 12,439 1 %

Total 1,247,328 100 %

 
9

Potential natural vegetation types within Prescott National Forest and 

occurrences of vascular plant taxa for which there is a viability concern 

 Following are descriptions of the number and diversity of vascular plant 

taxa (species, varieties, and subspecies) of viability concern (VPTVC) within 

each of the vegetation types listed in Table 2. It should be noted that occurrences 

of plant species in general are more a function of habitat type (primarily 

topography, substrate, percent canopy, and proximity to water) than to vegetation 

types (See Table 5, page 68, for a summary of VPTVC associated with habitat 

types within PNF). 

Semi‐Desert Grasslands

 Semi-desert grassland is often difficult to define because of humancaused changes over the past two centuries. Much of the semi-desert grassland, 

such as tobosa grassland, has been converted into scrubland with juniper and 

mesquite at higher elevations and creosote-cactus scrub at lower elevations. 

Fortunately, the most important habitat within semi-desert grassland, the Verde 

Formation, appears to been affected less than habitats with more fertile 

substrates, at least with respect to the occurrence of VPTVC. A large percentage 

of the Verde Formation within the PNF supports one or more VPTVC. The small 

amount of Verde Formation within PNF combined with the large number of 

VPTVC that occur there highlight the importance of management within the 

Verde Formation. A more detailed account of the Verde Formation and 

recommended conservation strategies is provided under Habitats of Special 

Concern, page 67. 

Great Basin and Pinyon Juniper Grasslands		

 Grasslands within PNF are the most variable of the vegetation types, 

especially in terms of values of vegetation parameters, including plant cover and 

diversity. Several VPTVC are represented in PNF grasslands, some of which 

could be indicators of grassland health as measured in terms of total diversity 

and abundance of organisms, and annual production of biomass. To date, there 

is little or no evidence that management efforts to facilitate the viability of VPTVC 

within grasslands is incompatible with efforts to maintain or increase grazing 

potential. 

 Certain substrates and topographies within the grasslands of PNF, notably 

calcareous alluvial soils and cobbly ridges and hillsides, support the majority of 

VPTVC. 
10

Pinyon‐Juniper Evergreen Shrub and Pinyon‐Juniper Woodlands

 In general, these habitats support little plant diversity except where they 

possess rare to infrequent habitat types, such as cliff faces and riparian areas. 

Several VPTVC occur primarily within both of these habitat types. 

Interior Chaparral

 Interior chaparral within PNF supports a low diversity of plant species and 

is not the primary habitat for any VPTVC. To date, there are no occurrences of 

VPTVC within the habitat, and there are only two taxa for which their occurrence 

is either likely or possible. 

Ponderosa Pine‐Evergreen Oak and Ponderosa Pine Gambel Oak Forests

 None of these vegetation types support a high diversity or abundance of 

VPTVC except where there are infrequent habitat types. Most of the VPTVC that 

occur in PNF forests are associated with riparian areas; moist, north-facing 

slopes; and rock faces, ledges, and outcroppings. 

Desert Communities

 There are no VPTVC that are known to occur within the true desert 

communities of PNF (excluding disclimax grassland). 

Riparian Forest

 Several VPTVC are associated with riparian forests within PNF, although 

most records are from where there is a fairly open canopy. Based on the habitat 

descriptions for records, the occurrences of VPTVC is related more to the 

presence of perennial water flow and less so to the presence of the riparian 

forest. 

 
11

Part 2. Identification of vascular plant taxa for which there is a viability 

concern 

Of the 55 vascular plant taxa (including species, varieties and subspecies) 

listed as a species of conservation concern (Species of Concern or Interest in the 

Prescott National Forest Ecological Sustainability Report) within the Prescott 

National Forest, 24 species are considered to have a viability concern. The 

remaining 31 taxa do not have an immediate viability concern because they re 

geographically widespread and common; have not yet been found within Forest 

boundaries; and/or occur in naturally well-protected habitats or in habitats 

resistant to grazing, fire, and other potential threats. Specific reasons for 

excluding these 31 taxa as viability concerns are given in Appendix A. In 

general, these species should remain on species of conservation concern lists 

and considered as target species whenever general rare plant surveys are 

conducted. 

In 2014, one additional plant taxa was assessed in response to updates to 

the Regional Forester’s sensitive species list for the National Forests within 

Arizona and New Mexico, published in the fall of 2013. Information about Greene 

milkweed (Ascepias uncialis) was added to Table 3 below and Appendix A of this 

report.

Table 3. Vascular plant taxa of conservation concern for Prescott National Forest, from: 

Prescott National Forest Ecological Sustainability Report 2009 (table updated in 2014) 

Taxon Common name 

Immediate 

viability 

concern Justification 

Abronia nana Dwarf sand verbena No Widespread and fairly 

common, collected only once 

in PNF but at edge of range 

Agastache rupestris Thread-leaf gianthyssop 

No Locality uncertain in PNF, 

widespread in AZ, NM 

Agave phillipsiana Phillip’s agave Yes Geographically limited, few 

individuals 

Agave delamateri Tonto basin agave Yes Geographically limited, few 

individuals 

Allium bigelovii Bigelow's onion No None, widespread in AZ, NM; 

habitat non-specific 

Anulocaulis leiosolenus var. 

leiosolenus 

Southwestern 

ringstem 

Yes Limited habitat and small 

populations 

Apodanthera undulata Melon-loco No Apparently a Chihuahuan 

Desert species that occurs in 

PNF at the edge of its range 

Arenaria aberrans Mt. Dellenbaugh 

sandwort 

Yes Limited range 

Asclepias unicialis Greene milkweed No Natural rarity/limited range Not 

yet found in Yavapai County 
12

Table 3. Vascular plant taxa of conservation concern for Prescott National Forest, from: 

Prescott National Forest Ecological Sustainability Report 2009 (table updated in 2014) 

Taxon Common name 

Immediate 

viability 

concern Justification 

Astragalus troglodytus Creeping milk-vetch Yes Limited distribution, sporadic 

occurrence 

Astragalus calycosus var. 

scaposus

King's milk-vetch No Many collections from AZ, NM, 

UT; common over large range 

Carex ultra Cochise sedge No Has not been found on Forest 

Cleome lutea var. jonesii Jones' spider-flower No Widespread in AZ, somewhat 

weedy in nature 

Cupressus arizonicus 

(pygmy) 

Arizona cypress 

pygmy form 

No Occurs within habitat that is 

not threatened by human or 

natural disturbances 

Cystopteris utahensis Utah bladder fern Yes Widespread over several 

states but considered rare 

Desmodium metcalfei Metcalfe's ticktrefoil Yes Limited range and distribution 

Draba asprella var. stelligera Rough whitlow-grass No Has not been found on the 

Forest but needs taxonomic 

verification 

Echinocereus yavapaiensis Yavapai claret-cup No Occurs primarily in protected 

habitats; common and 

abundant within its limited 

range. 

Ephedra fasciculata Nevada Mormon-tea No Widespread and common 

Erigeron saxatilis Cliff Fleabane No Occurs primarily in protected 

habitats 

Erigeron anchana Mogollon fleabane No Has not been found on Forest 

Eriogonum corymbosum var. 

glutinosum 

Wild buckwheat No Has not been found on Forest 

Eriogonum ripleyi Ripley's wildbuckwheat 

Yes Limited range and habitat 

Eriogonum ericifolium (E. 

ericifolium var. ericifolium) 

Heathleaf wild 

buckwheat 

Yes Limited range and habitat 

Eriogonum pulchrum (E. 

ericifolium var. pulchrum) 

Yavapai wild 

buckwheat 

No Has not been found on Forest 

Eriogonum arizonicum Arizona wildbuckwheat 

Yes Limited range and distribution 

and populations on somewhat 

restricted soil types 

Eriogonum heermannii var. 

floccosum 

Heermann's woolly 

wild-buckwheat 

No Occurs on protected habitat or 

at least where there are 

probably no conservation 

options 

Fremontodendron 

californicum 

California flannelbush No Although rare within PNF, wide 

ranging elsewhere; occurs in 

chaparral and is fire-tolerant 

Hedeoma diffusum Flagstaff pennyroyal Yes Limited range, populations in 

PNF may represent a new 

species 
13

Table 3. Vascular plant taxa of conservation concern for Prescott National Forest, from: 

Prescott National Forest Ecological Sustainability Report 2009 (table updated in 2014) 

Taxon Common name 

Immediate 

viability 

concern Justification 

Heuchera novamexicana New Mexico alumroot 

Yes Widespread in NM but very 

limited in AZ 

Heuchera eastwoodiae Eastwood alum-root Yes Limited range and habitat 

Lepidium montanum var. 

glabrum 

Mountain 

pepperweed 

No Has not been found on Forest 

Leptodactylon caespitosum 

(var. or sp. nov.) 

Matted prickly-phlox No Occurs primarily in protected 

habitats 

Lesquerella arizonica

(Physaria arizonica) 

Arizona bladderpod No Has not been found on Forest 

Lesquerella cinerea

(Physaria cinerea) 

Basin bladder-pod Yes Limited range and habitat 

Lesquerella pinetorum

(Physaria pinetorum) 

White Mountain 

bladderpod 

Yes Widespread in AZ, NM but not 

common 

Lotus mearnsii var. mearnsii Mearns lotus Yes Limited range and habitat 

Lupinus latifolius ssp. 

leucanthus 

Broadleaf lupine Yes Llimited distribution and 

habitat, current habitat fragile 

Margaranthus solanaceus Netted globecherry No Although rare within PNF, wide 

ranging especially in SE AZ 

Mertensia macdougalii Macdougal's 

bluebells 

Yes Limited distribution, many 

collections but often from 

same locality 

Nicotiana quadrivalvis var.

bigelovii 

Native tobacco No Not known to occur on Forest 

land, widespread in CA, OR 

Pediomelum mephiticum 

(PNF populations = P. 

verdiensis) 

Skunk-top scurfpea Yes Limited range and habitat, 

PNF populations being 

described as a new species 

Penstemon oliganthus Apache beardtongue No Fairly widespread with many 

localities, 1 locality within PNF 

but at SW edge of range 

Penstemon nudiflorus Flagstaff beardtongue No Limited distribution but 

common within its range, 

especially within PNF 

Perityle congesta Compacted rock 

daisy 

No Has not been found on Forest 

Phacelia rupestris Rock scorpionweed No Rare in AZ but widespread in 

NM, TX, and Mexico 

Phlox amabilis Arizona phlox Yes Limited range and distribution 

Polygala rusbyi Hualapai milkwort Yes Limited range and distribution 

Puccinellia parishii Parish's alkali grass No Has not been found on Forest 

Salvia dorrii ssp. mearnsii Mearns sage Yes Limited range and distribution 

Sporobolus interruptus Black dropseed Yes Limited distribution, possible 

importance as grazing 

indicator 

Stachys rothrockii Rothrock's hedgenettle 

No Has not been found on Forest 
14

Table 3. Vascular plant taxa of conservation concern for Prescott National Forest, from: 

Prescott National Forest Ecological Sustainability Report 2009 (table updated in 2014) 

Taxon Common name 

Immediate 

viability 

concern Justification 

Talinum validulum Western flame-flower No Occurs primarily in habitats 

little effected by grazing, fire, 

and other potential threats 

Thelypodiopsis ambigua var.

ambigua 

Long Valley 

tumblemustard 

No Has not been found on Forest 

Thelypteris puberula Showy maidenfern No Not known to occur within PNF 

Triteleia lemmoniae Oak creek triteleia Yes Limited range and distribution 

 
15

3. Life history, distribution and abundance, habitats, and 

potential threats for species for which there is a viability 

concern 

Agave delamateri 

Species overview

Populations of this species are largely clonal and thought to have 

originally been cultivated by pre-European cultures (Hodgson 1999). This brings 

into question its taxonomic validity and suggests that populations in the United 

States represent gametes brought from other regions (probably Mexico). The 

cultural significance of the species, therefore, may exceed its biological 

significance. 

Life history

Agave delamateri is a long-lived perennial with a basal rosette of semisucculent leaves. Stems generally take ten or more years to flower and then the 

central shoot dies. Clonal offshoots from the stem, however, continue to mature 

and produce additional offshoots. A single clone, therefore, lives indefinitely until 

it is killed by disease or some other natural or human-caused occurrence. Seeds 

for the species are unknown and, with without sexual reproduction, the species is 

almost certainly an evolutionary dead end. Gene flow, however, may occur 

between individuals of this species and A. chrysantha, which suggests that pollen 

of the former is viable (Hodgson 1999). In general, the nectar of agave flowers is 

an important food source for bats. 

Distribution and abundance

The species is endemic to Coconino, Gila, Maricopa, Pinal and Yavapai 

counties, Arizona with 101 occurrences listed in Seinet and two localities from 

additional sources. The total distribution range for Agave delamateri is 180 km. In 

Coconino County there are four localities (two of which are clones with same 

locality data) in the southern portion ranging only 5 km; in Gila County there are 

51 occurrences in the west-central portion, ranging 50 km; in Maricopa County 

there are three occurrences in the northern portion, ranging only 1km; and in 

Yavapai County there are 36 occurrences in the eastern portion, ranging 60 km. 

The remaining four collections do not have locality data. 
16

Five locations are listed for PNF ranging 61km, with two locations within a 

meter of each other. 

Habitat

Individuals of the species occur along drainages and ridges; with 

substrates including granite, red-brown silt, sandstone, limestone, and basalt 

rocks. Elevation ranges between 370m (1200ft) and 1601m (5250ft) with a mean 

elevation of 981m (3220ft). Vegetation types include high desert, desert 

grasslands, desert scrub, Juniper grassland, piñon-juniper woodland, and 

riparian areas. 

Known and potential threats

 There is no mention of threats for the species in Seinet. Agaves in 

general, however, are favorite food for javelina. Fire may be a threat in areas 

where vegetation is relatively dense. Given that the plants are probably subject to 

herbivory and the lack of seed production, the few individuals that occur within 

the Forest will probably be extirpated, if not through herbivory, then through 

attrition. How long these clones will survive in the wild is highly speculative and 

may range between a few years to a few centuries. 

Recommended conservation strategies

1. Surveys for new individuals 

Surveys within the general area of occurrence in the Forest would help determine 

a better estimate of individuals. Because new individuals may be found, this may 

be an important step prior to any further conservation or monitoring efforts. 

2. Propagation from offshoots 

Propagation from offshoots would be simple and ramets could be planted at 

various easily monitored sites. Since individuals often produce a large number of 

offshoots, there would probably be little damage to the longevity of the plant if 

some were taken for purposes of propagation. Clones could be established in 

test plots and public gardens in order to insure the genetic survival of the 

species. Although transplanting rare species is not generally recommended, this 

species may be an exception owing to its suspected history as a cultivar. 
17

3. Javelina deterrents 

Because deterring javelina may not be practicable, individuals of Agave 

delamateri within the Forest should first be monitored in order to determine 

whether there indeed is a problem. The purpose of fencing off individuals would 

be to deter herbivores such as javelina. Since there are only a few individuals 

known within the Forest, the amount of fence would not be extensive. Because of 

the cultural significance of the species, it may be possible to commandeer 

volunteers from, for example, the Highlands Center. The fence recommended by 

the Arizona Game and Fish Department is an electric one and, therefore, 

probably not practical for several reasons on Forest lands. Anti-javelina pellets 

are also available from nurseries. 

4. Fire management 

In the unlikely event that monitoring suggests fire may damage individuals, then it 

may be useful to remove some of the vegetation in the vicinity of the agave 

plants. Since these agaves generally occur in areas of sparse vegetation, efforts 

would probably be minimal. 

Recommended monitoring

After surveys have been done to determine whether additional clones exist within 

the Forest, occasional monitoring of individuals (every 5-10 years) would help 

determine the rate of attrition within the Forest and, therefore, aid in conservation 

efforts. Initial baseline data that would be helpful would include locations and 

number of individuals; stage of maturation (presence or absence of flowering 

stalks); presence or absence of seeds (presently unknown); evidence of 

herbivory, disease, die-off caused by drought or fire; evidence of off-road vehicle 

travel or other human disturbances. 

References

Hodgson, W. 1999. Agavaceae, agave family, part one. Journal of the ArizonaNevada Academy of Science 32(1):1-21. 

Agave phillipsiana 

Species overview
18

Like Agave delamateri, populations of this species are largely, if not 

entirely clonal, and were probably brought into the region as cultivars (Hodgson 

2001). Thus, many of the processes associated with the evolution and 

geographic distribution of natural populations are lacking in A. phillipsiana as 

well. 

Life history

Agave phillipsiana is a long-lived perennial with a basal rosette of semisucculent leaves. Stems generally take ten or more years to flower and then the 

central shoot dies. Clonal offshoots from the stem, however, continue to mature 

and produce additional offshoots. A single clone, therefore, lives indefinitely until 

it is killed by disease or some other natural or human-caused occurrence. 

Flowers open in September. Capsules and seeds were unknown when the 

species was published (Hodgson 2001). 

Distribution and abundance

The species is endemic to Yavapai, Coconino, and Gila County, Arizona 

with 38 occurrences listed in Seinet. The total distribution range for Agave 

phillipsiana is 314 km. In Coconino County, there are 15 localities in the 

northwest portion ranging 56 km; in Yavapai County, 21 localities in the northeast 

to the south-central portion of ranging 89 km, and in Gila County, two localities in 

the west-central portion ranging 21 km. Individuals per site vary from one to few 

with probably fewer than 100 individuals known for the species. 

Within the PNF, clones of this species occur primarily south of Wilhoit 

along the Hassayampa River and its tributaries. Twelve occurrences are spread 

over a distance of less than five km with some within 100 meters of one another. 

Clones of A. delamateri have been confused with those of A. phillipsiana and 

sightings south of Wilhoit listed as A. delamateri are probably for those of A. 

phillipsiana. 

Habitats

Individuals of the species occur on slopes, hilltops, and ridgelines; with 

substrates including granitic grus, and limestone or Basalt rocks. In elevation, 

they range between 700m (2290ft) and 1500m (4920ft) with a mean of 1120m 

(3650ft). Vegetation types include desert scrub, desert grassland, open piñon 

pine grassland, and Juniper grassland. 
19

Known and potential threats

 There is no mention of threats for the species in Seinet. Agaves in 

general, however, are favorite food for javelina. Fire may be a threat in areas 

where vegetation is relatively dense. Given that the plants are probably subject to 

herbivory and the lack of seed production, the few individuals that occur within 

the Forest will probably be extirpated, if not through herbivory, then through 

attrition. 

Recommended conservation strategies

1. Surveys for new individuals 

Surveys within the general area of occurrence in the Forest would help determine 

a better estimate of individuals. Because new individuals may be found, this may 

be an important step prior to any further conservation or monitoring efforts. 

2. Propagation from offshoots 

Propagation from offshoots would be simple and ramets could be planted at 

various easily monitored sites. Since individuals often produce a large number of 

offshoots, there would probably be little damage to the longevity of the plant if 

some were taken for purposes of propagation. Clones could be established in 

test plots and public gardens in order to insure the genetic survival of the 

species. Although transplanting rare species is not generally recommended, this 

species may be an exception owing to its suspected history as a cultivar. 

3. Javelina deterrents 

Because deterring javelina may not be practicable, individuals of Agave 

phillipsiana within the Forest could first be monitored in order to determine 

whether there indeed is a problem. The purpose of fencing off individuals would 

be to deter herbivores such as javelina. Since there are only a few individuals 

known within the Forest, the amount of fence would not be extensive. Because of 

the cultural significance of the species, it may be possible to commandeer 

volunteers from, for example, the Highlands Center. The fence recommended by 

the Arizona Game and Fish Department is an electric one and, therefore, 

probably not practical for several reasons on Forest lands. Anti-javalina pellets 

are also available from nurseries. 

4. Fire management 

In the unlikely event that monitoring suggests fire may damage individuals, then it 

may be useful to remove some of the vegetation in the vicinity of the agave 
20

plants. Since these agaves generally occur in areas of sparse vegetation, efforts 

would probably be minimal. 

Recommended monitoring

After surveys have been done to determine whether additional clones exist within 

the Forest, occasional monitoring of individuals (every 5-10 years) would help 

determine the rate of attrition within the Forest and, therefore, aid in conservation 

efforts. Initial baseline data that would be helpful would include locations and 

number of individuals; stage of maturation (presence or absence of flowering 

stalks); presence or absence of seeds (presently unknown); evidence of 

herbivory, disease, die-off caused by drought or fire; evidence of off-road vehicle 

travel or other human disturbances. 

References

Hodgson, W. C. 2001. Novelties in American Agave (Agavaceae). Novon,11 (4) 

410-416. 

Anulocaulis leiosolenus var. leiosolenus 

Species overview

 This is a taxonomically unique species and, although is one of the species 

that occurs on the Verde Formation, it is also known from a variety of other soils. 

It is a tall herb with large basal leaves and a few smaller stem leaves. The 

branches of the inflorescence are long and thin, bearing scattered large delicate 

white to pink flowers with long pink-purple stamens. 

Life history

Anulocaulis leiosolenus var. leiosolenus is probably a long-lived perennial 

herb from a large vertical tuberous taproot. The flowers emerge between late 

spring and early fall and, like many species within the family, are closed during 

mid-day. 

Distribution and abundance
21

 Populations of the taxon occur in Coconino, Mohave, and Yavapai 

counties, Arizona, westward into Nevada and eastward into New Mexico, Texas, 

and Chihuahua (Brian 2000). There are only twelve occurrences listed in Seinet. 

In Coconino County there are five occurrences in the west-central portion, 

ranging 109km, there is one occurrence on the east-central border of Mohave 

and Coconino counties, and in Yavapai County there are five occurrences in the 

east-central portion, ranging 39km, Two occurrences are recorded for PNF near 

road 136 near Lucky Canyon, 6km SW of Camp Verde (Seinet, Envirosystems 

Management, Inc. 2003). 

Habitats

 In Arizona, individuals occur on east-facing slopes; with substrates 

including calcareous clays and shales, gypsum, talus, limestone, zoraster 

granite, gray-white volcanic tuft, and vishnu schist. Elevation ranges between 

390m (1300ft) and 1500m (4920ft) with a mean elevation of 947m (3110ft). 

Vegetation types include desert scrub and desert riparian, and Aristida purpurea

grassland. 

Known and potential threats

 Because of it uniqueness, the species tends to be overcollected by 

botanists. This threat is exacerbated by the fact that there are often only a few 

individual per population. Species in the family are generally subject to 

herbivory. Because of its delicate nature, individuals of this taxon are particularly 

susceptible to herbivory and physical damage from human activities. 

Since, at least within PNF, it is known only to occur in the Verde Formation, 

threats to this habitat apply to this species (See discussion under habitats, p. 59). 

Recommended conservation strategies

 Like other taxa that occur primarily on the Verde Formation, conservation 

of habitat is of primary concern to the viability of the populations. For a more 

detailed account of the Verde Formation (p. 59) 

1. Surveys for new individuals 

Surveys within areas where the Verde formation occurs in the Forest would help 

ascertain the presence of any additional populations. Surveys for individuals of 

this taxon can be conducted concurrently with those for other taxa that occur 

within similar habitat. 
22

2. Prevention of off-road vehicle traffic 

Impediments to off-road use in areas where individuals of the taxon occurs are of 

primary importance. Closing two-tracks and minor Forest roads with large 

boulders and/or other vehicle-proof structures at access points may be effective 

in this regard. Signs suggesting alternate and legal ORV areas in the vicinity 

may be useful. 

4. Grazing management 

Although restricting cattle grazing may benefit populations of the taxon, wasted 

efforts in this regard may be avoided if populations are first monitored in order to 

ascertain if grazing is indeed a negative influence. In addition, if cattle are eating 

the plants, then other animals are probably eating them as well. If elk, for 

example, are impacting the site, then stronger fencing may need to be erected. 

4. Fire management 

Although historically habitats within the Verde Formation are not subject to fire, in 

years where non-native weeds, such as Bromus rubens (cheatgrass), are 

abundant, fire may be a problem. During such years, removal of weeds near 

individuals of Anulocaulis may be preventative. 

Recommended monitoring

Baseline data that recorded the presence or absence of impacts caused by 

grazing, browsing and other forms of herbivory; off-road vehicle use, weeds, fire, 

and other factors would be useful in determining better regime of conservation 

strategies. The interval of monitoring may also depend on baseline data. For 

example, if individuals of Anulocaulis appear to be healthy with no impacts, then 

monitoring could probably done less frequently. 

 

References

Brian, Nancy J. 2000. A field guide to the special status plants of Grand Canyon 

national Park. Science Center, Grand Canyon National Park, Arizona. 

Envirosystems Management, Inc. 2003. Rare plant and noxious weed survey on 

the Verde Ranger District, Prescott National Forest. 

Flora of North America Editorial Committee. 2003. Flora of North America. 4:29-

30 
23

Arenaria aberrans 

Species overview

 This species belongs to a somewhat taxonomically ambiguous group and, 

therefore, data should be regarded as tenuous until adequate diagnostic 

characters become available. In Kearney and Peebles (1960) the species is 

separated from its relatives by the bluntness of its sepals. 

Life history

 Very little is known about the life history of this perennial herb. The 

flowers are rather showy (ca. 1cm broad) and are open during the day from May 

to July (Kearney & Peebles 1960). 

Distribution and abundance

 The species is endemic to Apache, Coconino, Gila Mohave, and Yavapai 

counties with 25 occurrences listed in Seinet and four localities listed from 

additional sources. The total distribution range for Arenaria aberrans is 414km. In 

Apache County there is one occurrence in the south-central portion; in central 

Coconino County there are seven occurrences, ranging 85km, in central-west 

Gila County there is a single occurrence; in central Yavapai County there are 13 

occurrences, ranging 99km; and in Mohave County there are two occurrences, 

ranging 151km. The remaining five collections do not have locality data. Six 

locations are found in PNF ranging 47km, with three locations are within 1km of 

each other. 

Habitats

 Populations of the species tend to occur on south, north and northeastfacing slopes; with substrates including granite, Quaternary alluvial, basaltic soil, 

rich organic soil, and sandy soils. Elevation ranges between 1694m (5557ft) and 

2772m (7325ft) with a mean elevation of 2232m (7325ft). Vegetation types 

include chaparral, oak woodland, sagebrush community, and pine forest. 

Known and potential threats
24

 Most populations are recorded from habitats where fire is common but the 

effects of fire on the species are unknown. Being primarily herbaceous, plants 

are probably grazed by cattle. 

Recommended conservation strategies

1. Identification criteria 

Because the species appears morphological similar to its closest relatives, such 

as A. eastwoodiae, which also occur within the Forest, good diagnostic 

descriptions, including photographs would enable personnel to more easily 

identify the species. 

2. Surveys for new individuals 

Surveys for the species within in the Forest would help ascertain the presence of 

any additional populations. Because taxonomic identification is difficult, 

populations within the Forest presently thought to be Arenaria aberrans should 

be verified, then specific habitat criteria from those populations could be used to 

identify other potential areas of occurrence. 

3. Fire management 

Habitats where Arenaria aberrans occurs are subject to fire but the effects of fire 

on the species are undocumented. Initial and repeat monitoring may provide 

some insight into whether fire management would enhance the viability of this 

species. 

4. Grazing management 

Although the habitat for this species suggests that grazing probably does not 

impart a negative influence on populations, impacts of grazing should be tested 

through initial monitoring efforts. 

5. Prevention of off-road vehicle traffic 

As with grazing, this species occurs within habitats where off-road travel would 

not generally affect plants. 

Recommended monitoring

 Baseline data that record the presence or absence of impacts caused by 

grazing, browsing and other forms of herbivory; off-road vehicle use, weeds, fire, 
25

and other factors would be useful in determining better regime of conservation 

strategies. The interval of monitoring may also depend on baseline data. For 

example, if individuals of Arenaria aberrans appear to be healthy with no 

impacts, then monitoring could probably done less frequently. 

References

Arizona Game and Fish Department. 2004. Plant abstract for Arenaria aberrans. 

Phoenix, Arizona. 

Kearney, Thomas H., and Robert H. Peebles. 1960. Arizona Flora. University of 

California Press, Berkeley, California. 

Astragalus troglodytus 

Species overview

 A low herbaceous perennial with a loose rosette of basal leaves ca. 10cm 

long. It is a distinct species that is easily identified by its lack of an elongated 

stem, simple hairs, large (to 12mm) red-purple flowers, and the one-celled, 

nearly spherical fruits that occur in a cluster at the end of the fruiting stalk 

(Arizona Game and Fish Department 2004). 

Life history

 Individuals occur in local populations that are often widespread from one 

another. It is unknown whether this is a short-lived or long-lived perennial. 

Flowers develop from April to August. 

Distribution and abundance

 Astagalus troglodytus is endemic to Coconino and Yavapai Counties, 

Arizona, ranging only 140km; 48 occurrences are listed in Seinet and four 

localities listed from additional sources. In Yavapai County, there are ten 

occurrences in the central and east-central portions, ranging 133km; in southern 

Coconino County there are 42 occurrences, ranging 70km. Three locations are 

recorded from PNF within 1km of each other. 

Habitats

 Individuals of the species tend to occur on flats and southeast-facing 

slopes; with substrates including basalt rocks, gravel, other volcanic materials, 
26

rocky malapai soil, clay, sand, and loam. Elevation ranges between 1280m 

(4200ft) and 2400m (8198ft) with a mean elevation of 1889m (6199ft). Vegetation 

types include Bouteloua gracilis grassland, pine forests, piñon-juniper forests, 

and chaparral. 

Known and potential threats

 There are probably few, if any threats to populations of this species. 

Because of its low habit, it is probably not heavily grazed and belongs to a genus 

that is generally not palatable to cattle. Fire may have some effects on 

populations but individuals often occur in rocky substrate where fires are not 

prevalent. 

Recommended conservation strategies

1. Surveys for new individuals 

Surveys for the species within in the Forest would help ascertain the presence of 

any additional populations. Because the habitat for Astragalus troglodytus is 

widespread, surveys specific to the species should be done in the general vicinity 

of the known populations within the Forest. 

2. Fire management 

Habitats where Astragalus troglodytus occurs are subject to fire but the effects of 

fire on the species is undocumented. Initial and repeat monitoring may provide 

some insight into whether fire management would enhance the viability of this 

species. 

5. Prevention of off-road vehicle traffic 

Since habit for the species is often in level area with few trees and shrubs, offroad travel could impact individuals. Initial monitoring efforts may shed light on 

whether off-road vehicle travel has a negative impact on the viability of the 

species. If there are signs of off-road vehicle damage, then closing minor Forest 

roads or restricting nearby woodcutting activities may reduce effects. 

4. Grazing management 

Although species of this genus are not generally palatable to cattle, impacts of 

grazing should be considered during initial monitoring efforts. 
27

Recommended monitoring

 Baseline data that record the presence or absence of impacts caused by 

grazing, browsing and other forms of herbivory; off-road vehicle use, weed 

infestation, fire, and other factors would be useful in determining better regime of 

conservation strategies. Although the interval of monitoring may depend on 

baseline data, every three to five years would probably suffice for this species. 

References

Arizona Game and Fish Department. 2004. Plant abstract for Astragalus 

troglodytus. Pheonix, Arizona. 

Cystopteris utahensis 

Species overview

 A fairly distinctive fern, which was recently described (1991), is 

distinguished from its relatives by having elongate triangular leaves to 45cm long 

that are minutely glandular; dark brown somewhat lattice-like rhizome scales; and 

green or straw-colored petioles (Flora of North America Editorial Committee 1993).

Life history

 A delicate perennial herb spreading by rhizomes. The leaves die back in 

winter or during times of drought. 

Distribution and abundance

 A fairly wide-ranging species occurring in Utah (Grand, Kane, Utah and 

Washington counties), Arizona, Colorado (Moffat Co., Dinosaur National Monument), 

and disjunct in western Texas, and New Mexico (Arizona Game and Fish 

Department 2005). There are 44 records of the species in Seinet with a range of 

630km. In Arizona there are 33 localities ranging 369km; in north-central Apache 

County there are seven occurrences ranging 30km; in central and southern 

Coconino County there are 25 localities; and in northwest Yavapai County, there 

is one occurrence. The one occurrence in Yavapai County is from the northwest 

end of Juniper Mountain Wilderness Area and is the only site known for PNF. 
28

Habitats

 Individuals of the species tend to occur on west and north-facing slopes, 

ledges, crevices, cliff bases, seeps and rocky washes; with substrates including 

limestone, sandstone, dacite, talus deposits, limestone, chert, and silt. Elevation 

ranges between 1300m (4265ft) and 2615m (8580ft) with a mean elevation of 

1975m (6422ft). Vegetation types include oak-Juniper woodlands, riparian areas, 

hanging garden communities, spruce and fir forest in seeps, and Bouteloua 

grassland. 

Known and potential threats

 There are no known threats for this species. The population in PNF 

occurs in rock crevices at the base of a limestone cliff where grazing would be 

limited. 

Recommended conservation strategies

1. Identification criteria 

Because the species appears morphological similar to other ferns that occur 

within the Forest, good diagnostic descriptions, including photographs would 

enable personnel to more easily identify the species. 

2. Surveys for new individuals 

Surveys for the species within in the Forest would help ascertain the presence of 

any additional populations. Because the habitat for Cystopteris utahensis is 

widespread, surveys specific to the species should be done in the general vicinity 

of the known population within the Forest. 

3. Fire management 

Habitats where Cystopteris utahensis occurs are probably not frequented by fire. 

Monitoring, however, may provide some insight into whether fire management 

would enhance the viability of this species. 

4. Grazing management 

Although the habitat for this species suggests that grazing probably does not 

impart a negative influence on populations, impacts of grazing should be tested 

through initial monitoring efforts. 
29

5. Prevention of off-road vehicle traffic 

As with grazing, this species occurs within habitats where off-road travel would 

not generally affect plants. 

Recommended monitoring

 Baseline data that record the presence or absence of impacts caused by 

grazing, browsing and other forms of herbivory; off-road vehicle use, weeds, fire, 

and other factors would be useful in determining better regime of conservation 

strategies. Although the interval of monitoring may depend on baseline data, 

every three to five years would probably suffice for this species. 

References

Arizona Game and Fish Department. 2005. Plant abstract for Cystopteris 

utahensis. Phoenix, Arizona. 

Flora of North America Editorial Committee. 1993. Flora of North America. 2:267 

Desmodium metcalfei 

Species overview

 A fairly distinctive herbaceous perennial with thin weak stems, small pinkpurple flowers, and fruits that stick to socks and other means of dispersion. The 

leaves are trifoliate and mostly without hairs. 

Life history

 This low (generally less than 10cm tall) perennial often occurs in patches 

in the shade of riparian areas. The flowers emerge between August and 

October. 

Distribution and abundance

 The species has a wide range from Arizona to New Mexico and south into 

Sinaloa, Mexico, ranging over 1300km. There are16 occurrences listed in Seinet 

(15 in Arizona). In Arizona, it ranges over 450km; in Cochise County there are 

three occurrences in the central to south portion, ranging 113km; in south 
30

Coconino County, there is one locality; in Gila County there are five localities in 

the central and northern portions, ranging 135km, in southwest Pima County 

there is one locality; in Santa Cruz County there are three localities in the central 

and southwest portions, ranging 35km, and in southern Yavapai County there is 

one locality. There is one collection in Seinet that does not have locality data. 

The one occurrence in Yavapai County is southeast of Crown King in the 

Bradshaw Mountains and is also the only location known in PNF. 

Habitats

 Populations of the species tend to occur along washes; with substrates 

including limestone, granite, and limy shale. Elevation ranges between 822m 

(2700ft) and 2438m (8000ft) with a mean elevation of 1630m (5350ft). Vegetation 

types include ponderosa forest, riparian areas, grasslands, mixed 

evergreen/oak/riparian area, and mesquite washes. 

Known and potential threats

 Although there are no known threats to the species, very little is known 

about the autoecology of its populations. Desmodium is often considered a weed 

because of the fruits that cling to clothing. 

Recommended conservation strategies

1. Surveys for new individuals 

Surveys for the species within in the Forest would help ascertain the presence of 

any additional populations. Because the habitat for Desmodium metcalfei is 

widespread, surveys specific to the species should be done in the general vicinity 

of the known population within the Forest. 

2. Fire management 

Habitats where Desmodium metcalfei occurs are subject to fire but the effects of 

fire on the species is undocumented. Initial and repeat monitoring may provide 

some insight into whether fire management would enhance the viability of this 

species. 

3. Grazing management 
31

Although riparian habitats often incur heavy grazing, which could have a negative 

impact on populations, impacts of grazing should be tested through initial 

monitoring efforts. If grazing does negatively affect the viability of the species, 

then removing cattle from the drainage may be an option. 

4. Prevention of off-road vehicle traffic 

As with grazing, this species occurs within habitats where off-road travel may 

affect plants. Blocking access for motor vehicles to the drainage(s) where 

populations of Desmodium metcalfei occur may facilitate the viability of the 

species. 

Recommended monitoring

 Baseline data that record the presence or absence of impacts caused by 

grazing, browsing and other forms of herbivory; off-road vehicle use, weeds, fire, 

and other factors would be useful in determining better regime of conservation 

strategies. The interval of monitoring may also depend on baseline data. For 

example, if individuals of Desmodium metcalfei appear to be healthy with no 

impacts, then monitoring could probably done less frequently. Considering the 

exceptionally wide range of the species, preserving populations on the Forest 

may not greatly facilitate the viability of the species as a whole. 

References

Bleakly, David. 2009. New Mexico Rare Plant Taxon Report for Desmodium 

metcalfei. New Mexico Rare Plant Technical Council, New Mexico. 

Eriogonum arizonicum 

Species overview

Eriogonum arizonicum is not an official species of concern for the State of 

Arizona. It is a small perennial herb and, except for being confused with a more 

rare species, E. capillare, it is fairly distinctive. 

Life history

 Its small stature would suggest that individuals are short-lived. Flowers 

emerge March through June and again in August through November, depending 
32

on rains. Although it is a perennial, individuals may flower their first year (Flora 

of North America Editorial Committee 2005). 

Distribution and abundance

Endemic to Arizona, Eriogonum arizonicum has a range of 369km in 

Coconino, Gila, Maricopa, Mohave, Pima, Pinal, and Yavapai counties. There 

are 49 occurrences listed in Seinet and six localities listed from additional 

sources. In west-central Coconino County there is a single occurrence; in central 

Gila County there are two occurrences within a range of 1km; in northeast 

Maricopa County, there are twelve localities, ranging 74km; in southeast Mohave 

County there are five occurrences ranging 15km, in east-central Pima County 

there is one occurrence; in east-central Pinal County there are nine occurrences 

from the northern to the southeastern portion, ranging 114km, and in Yavapai 

County there are ten occurrences in the central and eastern portions, ranging 

104km. There are nine collections from Seinet that do not have adequate locality 

data. Within PNF there are five occurrences ranging 81km, with the closest two 

locations within 8km of each other. 

Habitats

 Populations of the species tend to occur on north, west and east-facing 

slopes, along washes, and above underground springs; with substrates including 

gravel, sand, cobble, basaltic hills, limestone, volcanic tuff, and agglomerate. 

Vegetation tends to be short and sparse. Elevation ranges between 390m 

(1300ft) and 3600m (11000ft) with a mean elevation of 1874m (6150ft). 

Vegetation types include southern desert scrub, chaparral, riparian, and 

roadsides. 

Known and potential threats

 The primary threat to individuals of the species is probably off-road traffic, 

since populations are often in areas where vegetation cover is low. For the same 

reason, fire is probably not a concern since there would be little fuel to carry it. 

Areas where the species occurs do not appear to be heavily grazed. 

Recommended conservation strategies

1. Prevention of off-road vehicle traffic 
33

Impediments to off-road use in areas where individuals of the species occurs 

may prove necessary depending on data gathered during initial monitoring 

efforts. The closing two-tracks and minor Forest roads with large boulders and/or 

other vehicle-proof structures at access points may be effective in this regard. 

For roadside populations, such management may be counter-productive, since 

individuals of Eriogonum arizonicum would probably not have been there in the 

first place if were not for the road. After initial observations of a population in 

question, it may be surmised whether the road or the plant population occurred 

first. 

2. Fire management 

Since habitats where Eriogonum arizonicum occur are generally not subject to 

fire, it may be expedient to consider fire management only after any effects of fire 

are documented by monitoring of populations. 

3. Grazing management 

As with fire, since habitats where Eriogonum arizonicum occur are generally not 

subject heavy grazing, it may also be expedient to consider range management 

only after any effects of cattle grazing are documented by monitoring of 

populations. 

Recommended monitoring

 Baseline data that record the presence or absence of impacts caused by 

grazing, browsing and other forms of herbivory; off-road vehicle use, weeds, fire, 

and other factors would be useful in determining better regime of conservation 

strategies. Although the interval of monitoring may depend on baseline data, 

every three to five years would probably suffice for this species. 

References

Flora of North America Editorial Committee. 2005. Flora of North America. 5:392 

Eriogonum ericifolium 

Species overview

 A distinctive perennial herb that looks like a stunted heather. Until 

recently, the species was thought to include E. ericifolium var. pulchrum but the 
34

authority has recently elevated the latter to its own species, E. pulchrum. In any 

case, the two taxa are very distinct from one another, the leaves of E. ericifolium

being glabrous on the upper surface and those of E. pulchrum short floccose. 

There are no populations of E. pulchrum known from PNF. 

Life history

 Individuals occur in sometimes dense and very localized populations. 

Flowers emerge between August and November. The leaves remain green 

throughout the winter. In terms of number and distribution of populations, this 

may be the rarest species that occurs on the Forest. 

Distribution and abundance

 The species is endemic to Mohave, and Yavapai counties, Arizona, with 

12 occurrences listed in Seinet and 13 localities listed from additional sources. 

The total distribution rang for Eriogonum ericifolium is 219km with, one locality is 

located in the northern portion of Mohave County, and the remaining 22 localities 

are located in the eastern portion of Yavapai County ranging 31km. One location 

is found in PNF, in the White Hills, SE of Cottonwood. 

Habitats

 Individuals of the species tend to occur on north, west and south-facing 

slopes, along washes, and in shallow pockets of sandy soil; with substrates 

including gravel, sand, basalt, limestone, sandstone, chert, silt, and calcareous 

substrate. Elevation ranges between 1067m (3500ft) and 1770m (5807ft) with a 

mean elevation of 1418m (4635ft). Vegetation types include high desert, and 

piñon Juniper woodlands. In PNF, the population occurs on the Verde 

Formation. 

Known and potential threats

 There are no known threats and few potential threats for the species. 

Since, at least within PNF, it is known only to occur in the Verde Formation, 

threats to this habitat apply to this species (See discussion under habitats). 

Recommended conservation strategies
35

 Like other taxa that occur primarily on the Verde Formation, conservation 

of habitat is of primary concern to the viability of the populations. Fortunately, 

since populations include large numbers of individuals, occasional mortality of a 

few individuals would probably not be as important as it would be for certain 

other taxa, such as Anulocaulis leiosolenus. 

1. Surveys for new individuals 

Surveys within areas where the Verde formation occurs in the Forest would help 

ascertain the presence of any additional populations. Surveys for individuals of 

this taxon can be conducted concurrently with those for other taxa that occur 

within similar habitat, primarily the Verde Formation. 

2. Prevention of off-road vehicle traffic 

Impediments to off-road use in areas where individuals of the taxon occurs are of 

primary importance. Closing two-tracks and minor Forest roads with large 

boulders and/or other vehicle-proof structures at access points may be effective 

in this regard. Signs suggesting alternate and legal ORV areas in the vicinity 

may be useful. 

4. Grazing management 

Although restricting cattle grazing may benefit populations of the species, wasted 

efforts in this regard may be avoided if populations are first monitored in order to 

ascertain if grazing is indeed a negative influence. In addition, if cattle are eating 

the plants, then other animals are probably eating them as well. If elk, for 

example, are impacting the site, then stronger fencing may need to be erected. 

4. Fire management 

Although historically habitats within the Verde Formation are not subject to fire, in 

years where non-native weeds, such as Bromus rubens (cheatgrass), are 

abundant, fire may be a problem. During such years, removal of weeds near 

individuals of Eriogonum ericifolium may be preventative. 

Recommended monitoring

 Baseline data that recorded the presence or absence of impacts caused 

by grazing, browsing and other forms of herbivory; off-road vehicle use, weeds, 

fire, and other factors would be useful in determining better regime of 

conservation strategies. The interval of monitoring may also depend on baseline 

data. For example, if individuals of Eriogonum ericifolium appear to be healthy 

with no impacts, then monitoring could probably done less frequently. 
36

References

Flora of North America Editorial Committee. 2005. Flora of North America. 5:254-

255, 

Eriogonum ripleyi 

Species overview

Eriogonum ripleyi is a distinctive perennial herb or subshrub with the 

appearance of a bonsai conifer. Similar in habit to E. ericifolium but the upper 

surfaces of the leaves in E. ripleyi are short and densely hairy. Populations are 

generally rare and widespread, even within its most frequent habitat, the Verde 

Formation. Individuals of the species are often locally abundant. 

Life history

 Although individuals of Eriogonum ripleyi appear to be long-lived, there is 

no supporting data to this effect in the literature. The somewhat showy clusters 

of flowers emerge between March and June. The leaves remain green 

throughout the winter. 

Distribution and abundance

 The species is endemic to Maricopa, Mohave, and Yavapai counties 

Arizona, with 29 occurrences listed in Seinet and 15 localities listed from 

additional sources. The total distribution range for Eriogonum ripleyi is 321km; in 

north-central Maricopa County there are seven occurrences, ranging 10km; in 

northern Mohave County there is one occurrence (type locality); and in northwest 

and east-central Yavapai County there are 28 localities, ranging 160km. The 

remaining eight collections from Seinet have insufficient locality data. Six 

occurrences for the species are spread over PNF ranging 41 km, with five within 

1km or each other. 

Habitats

 Individuals of the Eriogonum ripleyi tend to occur on south-facing slopes; 

with substrates including white chalky carbonate, gravel silt, gypsum, tertiary lake 

beds (Verde Formation), volcanic tuff, ash, and sandstone. Elevation ranges 
37

between 616m (2000ft) and 1848m (6062ft) with a mean elevation of 1232m 

(4041ft). Vegetation types include piñon-juniper and desert scrub. 

Known and potential threats

 There are no known threats and few potential threats for the species. 

Since, at least within PNF, it is known only to occur in the Verde Formation, 

threats to this habitat apply to this species (See discussion under habitats). 

Individuals of Eriogonum ripleyi occur abundantly on disturbed soils of the 

abandoned U. S. Mine in PNF. 

Recommended conservation strategies

 Like other taxa that occur primarily on the Verde Formation, conservation 

of habitat is of primary concern to the viability of the populations. Fortunately, 

since populations include large numbers of individuals, occasional mortality of a 

few individuals would probably not be as important as it would be for certain 

other taxa, such as Anulocaulis leiosolenus. 

1. Surveys for new individuals 

Surveys within areas where the Verde formation occurs in the Forest would help 

ascertain the presence of any additional populations. Surveys for individuals of 

Eriogonum ripleyi can be conducted concurrently with those for other taxa that 

occur within similar habitat, primarily the Verde Formation. 

2. Prevention of off-road vehicle traffic 

Impediments to off-road use in areas where individuals of the taxon occurs are of 

primary importance. Closing two-tracks and minor Forest roads with large 

boulders and/or other vehicle-proof structures at access points may be effective 

in this regard. Signs suggesting alternate and legal ORV areas in the vicinity 

may be useful. For example, the population at the US mine are easily 

assessable to ORV’s but simple steps could be taken (probably a strong gate 

and minimum fencing) to keep vehicles from entering the area. 

4. Grazing management 

Although restricting cattle grazing may benefit populations of the species, wasted 

efforts in this regard may be avoided if populations are first monitored in order to 

ascertain if grazing is indeed a negative influence. In addition, if cattle are eating 

the plants, then other animals are probably eating them as well. If elk, for 

example, are impacting the site, then stronger fencing may need to be erected. 
38

4. Fire management 

Although historically habitats within the Verde Formation are not subject to fire, in 

years where non-native weeds, such as Bromus rubens (cheatgrass), are 

abundant, fire may be a problem. During such years, removal of weeds near 

individuals of Eriogonum ripleyi may be preventative. 

Recommended monitoring

 Baseline data that recorded the presence or absence of impacts caused 

by grazing, browsing and other forms of herbivory; off-road vehicle use, weeds, 

fire, and other factors would be useful in determining better regime of 

conservation strategies. The interval of monitoring may also depend on baseline 

data. For example, if individuals of Eriogonum ripleyi appear to be healthy with 

no impacts, then monitoring could probably done less frequently. 

References

Flora of North America Editorial Committee. 2005. Flora of North America. 5:253. 

Hedeoma diffusum 

Species overview

Hedeoma diffusum is a small perennial herb that often forms low dense 

mats, has simple, entire leaves, and bears rather showing pink-purple flowers 

that are hairy on the inside. It is easily distinguished from its closest relative, H. 

nanum, by its larger flowers, turpentine-like odor, and pubescent winter leaves. 

Another close relative, H. drummondii, has an odor of mint and glabrous winter 

leaves. The only other Hedeoma sympatric with H. diffusum is H. oblongifolium, 

which has a similar odor to H. diffusum but has strict (erect and straight) stems, 

often dentate leaves, and a corolla with essentially no hairs inside. Individuals of 

typical H. diffusum, however, differ in habit and flower characteristics from those 

recorded by Baker & Wright (1993) from PNF. The population from PNF, 

therefore, may belong to their own undescribed species. 

Life history
39

 Stems and leaves of Hedeoma diffusum persist throughout the winter, 

although its winter leaves are generally more pubescent and crowded than its 

warm-season leaves. Flowers emerge between May and August. 

Distribution and abundance

Hedeoma diffusum is endemic to Coconino, Mohave, Pima, and Yavapai 

counties, Arizona, with 56 occurrences listed in Seinet and 14 localities from 

additional sources. The total distribution range for H. diffusum is 468km; in southcentral Coconino County, there are 43 occurrences, ranging 38km; in northeast 

Mohave County, there is one occurrence; in northern Pima County, there is one 

occurrence; and in northeastern Yavapai County, there are 20 occurrences, 

ranging 29km. The remaining five records from Seinet have insufficient locality 

data. 

Habitats

 Populations Individuals of Hedeoma diffusum tend to occur on north and 

east-facing slopes, bottom of ravines, and cliffs; with substrates including 

cobbles, and sandstone. Elevation ranges between 1386m (4547ft) and 2131m 

(6991ft) with a mean elevation of 1758m (5756ft). Vegetation types include oak, 

juniper-piñon woodland, and ponderosa pine forest. 

Known and potential threats

 Most populations are recorded from habitats where fire is common but the 

effects of fire on the species are unknown. The generally rocky micro-habitat of 

the species may protect individuals from most fires, as well as off-road vehicle 

use, and cattle grazing. Within PNF, populations generally occur in wilderness 

areas that are far removed from human influence. There is some concern of 

potential impacts of invasive weeds, such as Linaria dalmatica (Arizona Game 

and Fish Department (2003). 

Recommended conservation strategies

1. Taxonomic studies 

Because of the taxonomic confusion between the typical Hedeoma diffusum and 

populations within PNF, a taxonomic comparison between the two forms is 

needed in order to establish which populations actually belong to H. diffusum and 
40

to the potentially new taxon. It may be that, after review, individuals of one of the 

taxa are extremely rare and deserve heightened conservation efforts in order to 

insure viability of the species. A simple classical approach to the problem my 

suffice and would include a preliminary morphological comparison based on 

herbarium material and then visits to selected population sites in the late spring, 

when morphological measurements and more adequate photographs could be 

made of fresh material, and material collected for chromosomes counts. 

2. Fire management 

It has been suggested that at least for some populations, prescribed burning may 

facilitate the maintenance of populations by reducing overstory and litter (Arizona 

Game and Fish Department (2003). Prescribed burning may also act as a 

deterrent to catastrophic fires.

3. Grazing management 

Although the habitat for this species suggests that grazing probably does not 

impart a negative influence on populations, impacts of grazing should be tested 

through initial monitoring efforts. 

2. Surveys for new individuals 

Since several populations of, at least the new taxon, are known within PNF, 

specific surveys for the species are not immediately necessary in order to 

evaluate the populations taxonomically and to begin monitoring them. 

5. Prevention of off-road vehicle traffic 

For populations recorded within PNF, it is doubtful that off-road vehicle traffic is a 

conservation consideration. However, it would be expedient to include notes on 

any evidence of ORV impacts during monitoring. 

Recommended monitoring

 Baseline data that record the presence or absence of impacts caused by 

grazing, browsing and other forms of herbivory; off-road vehicle use, weeds, fire, 

and other factors would be useful in determining better regime of conservation 

strategies. In addition, because of the taxonomic confusion concerning the 

species, morphological data should also be recorded. The interval of monitoring 

may also depend on baseline data. For example, if individuals of appear to be 

healthy with no impacts, then monitoring could probably done less frequently. 
41

References

Arizona Game and Fish Department. 2003. Plant abstract for Hedeoma diffusum. 

Phoenix, Arizona. 

Baker, M. and T. Wright. 1993. A Botanical survey of the Apache Creek, Juniper 

Mesa, Sycamore Canyon and Woodchute wilderness areas of the Prescott 

National Forest. Report for the Chino Valley Ranger District of Prescott National 

Forest, Arizona. 

Heuchera eastwoodiae 

Species overview

Heuchera eastwoodiae is a unique species within the genus with six 

sepals. It is therefore, easily identified in the field with a hand lens. It is a low 

herb with attractive dark green, often mottled, suborbicular (nearly circular) 

leaves. Unlike many of its relatives that are grown in horticulture for both their 

attractive leaves and showy flowers, H. eastwoodiae flowers are comparatively 

inconspicuous with no or a very reduced corolla. 

Life history

 Although the leaves of Heuchera eastwoodiae persist through the winter, 

they often turn purple or red. Flowers appear between May and August (Flora of 

North America Editorial Committee 2009). 

Distribution and abundance

Heuchera eastwoodiae is endemic to Coconino, Gila, Maricopa, and 

Yavapai counties, Arizona, with 24 occurrences listed in Seinet and 26 localities 

from additional sources. The total distribution range for H. eastwoodiae is 255km; 

in east-central Coconino County, there is one occurrence; in north, central, and 

west Gila County there are four occurrences, ranging 112km; in east Maricopa 

County, there is one occurrence; throughout Yavapai County, there are 43 

occurrences, ranging 157km. The remaining record from Seinet has insufficient 

locality data. Thirty-three occurrences for the species are wide spread over PNF, 

ranging 79km. 
42

Habitats

 Individuals of the species tend to occur on North, Southwest and Eastfacing slopes, and along ridges; with substrates including basalt, granite, and 

granite schist. Elevation ranges between 1280m (4200ft) and 2400m (7870ft) 

with a mean elevation of 1839m (6035ft). Vegetation types include mixed 

Conifer, Aspen forests, and Highland forests. 

Known and potential threats

 Most populations are recorded from habitats where fire is common but the 

effects of fire on the species are unknown. Although these delicate herbs are 

probably grazed by cattle, they generally occur in microhabitats that are 

inaccessible. 

Recommended conservation strategies

1. Fire management 

Habitats where Heuchera eastwoodiae occurs are subject to fire but the effects 

of fire on the species are undocumented. Prescribed burning may facilitate the 

maintenance of populations by reducing overstory and litter. Prescribed burning 

may also act as a deterrent to catastrophic fires. Initial and repeat monitoring 

may provide some insight into whether fire management would enhance the 

viability of this species. 

2. Surveys for new individuals 

Surveys for the species within in the Forest would help ascertain the presence of 

any additional populations. Such knowledge would aid in assessing the rarity of 

the species and in turn its priority in Forest management. 

4. Grazing management 

Although the habitat for this species suggests that grazing probably does not 

impart a negative influence on populations, impacts of grazing should be tested 

through initial monitoring efforts. 

5. Prevention of off-road vehicle traffic 

As with grazing, this species occurs within habitats where off-road travel would 

not generally affect plants. 
43

Recommended monitoring

 Baseline data that record the presence or absence of impacts caused by 

grazing, browsing and other forms of herbivory; off-road vehicle use, weeds, fire, 

and other factors would be useful in determining better regime of conservation 

strategies. Although the interval of monitoring may also depend on baseline 

data, monitoring selected populations every three to five years would probably be 

sufficient to detect new threats and address the viability of the species. 

References

Flora of North America Editorial Committee. 2009. Flora of North America. 8:102 

Heuchera novamexicana 

Species overview

Heuchera novamexicana is similar in habit and leaf morphology to other 

species of the genus within PNF. Like H. eastwoodiae, it has short stamens 

(shorter than the sepals) and short pistils. The most common species in the 

forest, H. rubescens has long stamens and pistils. The flowers of both H. 

novamexicana and H. rubescens differ from those of H. eastwoodiae in being five 

parted and possessing a showy corolla. 

Life history

 Although the leaves of Heuchera novamexicana persist through the 

winter, they often turn purple or red. Flowers generally appear in June (Flora of 

North America Editorial Committee 2009). 

Distribution and abundance

Heuchera novamexicana has a range from Arizona to New Mexico, 

ranging 638km. There are 67 occurrences listed in Seinet and four localities from 

additional sources. In Arizona, H. novamexicana, has ten occurrences, ranging 

328km; in south Apache County, there are two occurrences, ranging 33km; in 

south central Coconino County, there are three occurrences, ranging 2km; in 

south Gila County, there are four occurrences, ranging 19km; and south Graham 

County, there is one occurrence. In New Mexico, H. novamexicana, has 57 

occurrences, ranging 351km; throughout Catron County, there are ten 

occurrences, ranging132km; in northern Cibola County, there is one occurrence; 
44

in central Dona Ana County, there are three occurrences, ranging 5km; in north 

central Grant County, there are eight occurrences, ranging 60km; in central 

Lincoln County, there is one occurrences; in north Luna County, there is one 

occurrence; in east and west Sierra County, there are eight occurrences, ranging 

137km; and in south and central Socorro County, there are six occurrences, 

ranging 62km. The remaining 12 occurrences have insufficient locality data. 

Three occurrences for the species are in PNF, ranging 2km; all three 

occurrences are in the vicinity of Tule Canyon, 25km northeast of Sedona. 

Habitats

 Individuals of the species tend to occur on southwest and north-facing 

steep slopes, above riparian areas, and at base of boulders; with substrates 

including granite, sandstone, sandy soil, and deep humus. Elevation ranges 

between 883m (2900ft) and 3350m (11000ft) with a mean elevation of 2438m 

(8000ft). Vegetation types include pine/oak forest, piñon-juniper communities, 

Douglas fir and ponderosa pine forests. 

Known and potential threats

 Most populations of Heuchera novamexicana are recorded from habitats 

where fire is common but the effects of fire on the species are unknown. 

Although these delicate herbs are probably grazed by cattle, they generally occur 

in microhabitats that are inaccessible. 

Recommended conservation strategies

1. Fire management 

Habitats where populations of Heuchera novamexicana occur are subject to fire 

but the effects of fire on the species are undocumented. Prescribed burning may 

facilitate the maintenance of populations by reducing overstory and litter. 

Prescribed burning may also act as a deterrent to catastrophic fires. Initial and 

repeat monitoring may provide some insight into whether fire management would 

enhance the viability of this species within the Forest. 

2. Surveys for new individuals 

Surveys specific for Heuchera novamexicana within in the Forest would help 

ascertain the presence of any additional populations. Such knowledge would aid 
45

in assessing the rarity of the species and in turn its priority in Forest 

management. 

4. Grazing management 

Although the habitat for this species suggests that grazing probably does not 

impart a negative influence on populations, impacts of grazing should be tested 

through initial monitoring efforts. 

5. Prevention of off-road vehicle traffic 

As with grazing, this species occurs within habitats where off-road travel would 

not generally affect plants. 

Recommended monitoring

 Baseline data that record the presence or absence of impacts caused by 

grazing, browsing and other forms of herbivory; off-road vehicle use, weeds, fire, 

and other factors would be useful in determining better regime of conservation 

strategies. Although the interval of monitoring may also depend on baseline 

data, monitoring selected populations every three to five years would probably be 

sufficient to detect new threats and address the viability of the species. 

References

Flora of North America Editorial Committee. 2009. Flora of North America. 8:103 

Lesquerella cinerea (Physaria cinerea) 

Species overview

Lesquerella cinerea is a small gray-green densely pubescent perennial 

from a short, branched caudex (thickened stem that occurs below on near the 

soil surface). Its leaves are ovate to suborbicular, which is usually broad for the 

genus. The fruits are pubescent and are borne on fairly straight pedicels. In 

Lesquerella arizonica, which also occurs on the Forest, the fruits are also 

pubescent but, unlike L. cinerea, the basal leaves are similar in shape to the 

stems leaves and the leaves are not well differentiated from their petioles. 

Life history
46

 Although, the herbage of Lesquerella cinerea often remains green and 

visible during the winter, individuals are generally short-lived. Flowers appear 

between March and May. 

Distribution and abundance

Lesquerella cinerea is endemic to Coconino, Maricopa, Mohave, and 

Yavapai counties, Arizona, with 58 occurrences listed in Seinet and five 

occurrences from additional sources. The total distribution range for L. cinerea is 

293km; in north central and south Coconino County, there are eleven 

occurrences, ranging 202km; in south Coconino County and along the border of 

Coconino and Yavapai counties, there are eleven occurrences, ranging 11km; 

along the northern border of Maricopa County, there are eight occurrences, 

ranging 2km; in southeast Mohave County, there are seven occurrences, ranging 

59km, and in south and central Yavapai county, there are 38 occurrences, 

ranging 140km. Ten occurrences for the species are spread over PNF, ranging 

75km; three occurrences are in the vicinity of Juniper Mesa, five occurrences are 

in the vicinity of the Black Hills east of Cottonwood, and two occurrences are in 

the vicinity of the Antelope Hills north of Cottonwood. 

Habitats

 Individuals of the species tend to occur on east-facing rocky slopes and 

ridgelines; with substrates including limestone, sandstone cobble, calcareous 

soils, gypsum soils, fossiliferous chert, and white lacustrine outcrops. Elevation 

ranges between 539m (1770ft) and 1889m (6200ft) with a mean elevation of 

1889m (914ft). Vegetation types include piñon-Juniper, pine forest, Sonoran 

Desert, and chaparral. 

Known and potential threats

 Because individuals of Lesquerella cinerea occur in a variety of habitats 

and their habit is rather low and inconspicuous, threats to populations are 

probably minor and of little concern with respect to Forest management. Threats 

that could potential impact individuals are off-road vehicle use, herbivory, 

including grazing, and fire. Because they are short-lived, any individuals killed by 

occasional off-road use are probably not critical to viability of a population. The 

same could be said about grazing. In addition, the species being fairly common 

in grasslands where both grazing and fire occurs suggested that it has adapted 

to these impacts. 
47

Recommended conservation strategies

 Because of the varied habitats and large geographical distribution of 

Lesquerella cinerea within PNF, the following recommended conservation might 

be considered a low priority with respect to efforts centering on more rare and 

potentially threatened species, at least until occasional monitoring suggests 

otherwise. 

1. Prevention of off-road vehicle traffic 

Off-road vehicle use is probably the most important potential impact on 

individuals of Lesquerella cinerea. The impact, however, may have more to do 

with the general health of the habitat verses the impact to specific individuals. 

Since some populations do occur within the Verde Formation, efforts to protect 

that habitat would facilitate the efforts to enhance the viability of this species as 

well. Since the health of grasslands is of primary concern to the Forest, 

grassland management where populations of L. cinerea occur may be of 

particular concern. Perhaps it would be helpful to entertain the question as to 

whether L. cinerea is an indicator of healthy grassland, at least on certain soil 

types. In any case, impacts of off-road vehicle use should be reviewed through 

initial monitoring efforts. 

2. Grazing management 

Although the nature of habitats for this species suggests that grazing could have 

a negative influence on populations, they could just as easily have a positive 

influence. In this respect, occasional monitoring would be very useful in 

determining the effects of grazing. See also the discussion of grasslands under 

off-road vehicle use. 

3. Fire management 

Fire management for this species probably parallels that for grazing management 

and efforts would be greatly facilitated by first monitoring selected populations . 

4. Surveys for new individuals 

Because of the rather large geographical distribution and variety of habitats of 

Lesquerella cinerea within PNF, there are probably sufficient populations to 

initiate monitoring of the species. 

Recommended monitoring
48

 Baseline data that record the presence or absence of impacts caused by 

grazing, browsing and other forms of herbivory; off-road vehicle use, weeds, fire, 

and other factors would be useful in determining better regime of conservation 

strategies. Although the interval of monitoring may also depend on baseline 

data, monitoring selected populations every three to five years would probably be 

sufficient to detect new threats and address the viability of the species. 

References

Flora of North America Editorial Committee. 2010. Flora of North America. 7:631-

632 

Lesquerella pinetorum (Physaria pinetorum) 

Species overview

Lesquerella pinetorum is a small gray-green densely pubescent perennial 

from a short, branched caudex with one to several stems. Its basal leaves are 

rhombic to elliptic, unlike the broad leaves of L. cinerea. Also unlike L. cinerea, 

the fruits of L. pinetorum are glabrous and are borne on mostly curved or even 

sigmoid pedicels. In Lesquerella arizonica, which also occurs on the Forest, the 

fruits are pubescent and the basal leaves are similar in shape to the stems 

leaves and the leaves are not well differentiated from their petioles. 

Life history

 Although, the herbage of Lesquerella pinetorum often remains green and 

visible during the winter, individuals are generally short-lived. Flowers appear 

between April and June (Flora of North America Editorial Committee 2010). 

Distribution and abundance

 Lesquerella pinetorum has a wide range from Arizona to New Mexico and 

into Texas, ranging 771km. There are 38 occurrences listed in Seinet and one 

occurrence from an additional source. In Arizona, L. pinetorum, has 23 

occurrences, ranging 558km; in south Apache County, there is one occurrence; 

in east central Cochise County, there is one occurrence; in north, central, and 

south Coconino County, there are six occurrences, ranging 226km; in north Gila 

County, there are two occurrences, ranging 2km; in central and west Graham 

County, there are four occurrences, ranging 59km; in west central Pinal County, 
49

there is one occurrence; and in north Yavapai County, there are eight 

occurrences, ranging 148km. In New Mexico, L. pinetorum, has 12 occurrences, 

ranging 315km; in east Bernalillo County, there is one occurrence; in central 

Grant County, there are three occurrences, ranging 29km; in southwest Lincoln 

County, there are two occurrences, ranging only 2km; in east Sierra County, 

there is one occurrence; and east central Otero County, there are five 

occurrences, ranging 29km. In Texas there is only one occurrence in north 

Hudspeth County. Three occurrences for the species are in PNF, ranging 15km; 

all three occurrences are in the vicinity of Prescott. 

Habitats

 Individuals of Lesquerella pinetorum occur on various slope aspects along 

riparian banks; with substrates that include sandy gravel, igneous, and limestone 

cobble. Elevation ranges between 1300m (4590ft) and 2400m (7870ft) with a 

mean elevation of 2051m (6730ft). Vegetation types include mixed conifer-oak 

forest, pine forest, (open meadows in forest), and Pseudotsuga menziesii forest 

habitats. 

Known and potential threats

 Because individuals of Lesquerella pinetorum occur in a variety of habitats 

and their habit is rather low and inconspicuous, threats to populations are 

probably minor and of little concern with respect to Forest management. Threats 

that could potential impact individuals are off-road vehicle use, herbivory, 

including grazing, and fire. Because they are short-lived, any individuals killed by 

occasional off-road use or grazing are probably not critical to viability of a 

population. 

Recommended conservation strategies

 Because of the varied habitats and large geographical distribution of 

Lesquerella cinerea within PNF, the following recommended conservation might 

be considered a low priority with respect to efforts centering on more rare and 

potentially threatened species, at least until occasional monitoring suggests 

otherwise. 

Recommended conservation strategies

1. Fire management 
50

Habitats where populations of Lesquerella pinetorum occur are subject to fire but 

any potential effects of fire on the species are undocumented. Prescribed 

burning may facilitate the maintenance of populations by reducing overstory and 

litter. Prescribed burning may also act as a deterrent to catastrophic fires. Initial 

and repeat monitoring may provide some insight into whether fire management 

would enhance the viability of this species within the Forest. 

2. Surveys for new individuals 

Surveys specific for Lesquerella pinetorum within in the Forest would help 

ascertain the presence of any additional populations. Such knowledge would aid 

in assessing the rarity of the species and in turn its priority in Forest 

management. 

4. Grazing management 

Although there is a potential for grazing within habitats for this species, the low 

stature of individuals of Lesquerella pinetorum may reduce its susceptibility. In 

any case, impacts of grazing should be tested through initial monitoring efforts. 

5. Prevention of off-road vehicle traffic 

As with grazing, this species occurs within habitats where off-road travel might 

affect plants but any impacts should be documented through the monitoring of 

selected populations before management practices are considered. 

Recommended monitoring

 Baseline data that record the presence or absence of impacts caused by 

grazing, browsing and other forms of herbivory; off-road vehicle use, weeds, fire, 

and other factors would be useful in determining better regime of conservation 

strategies. Although the interval of monitoring may also depend on baseline 

data, monitoring selected populations every three to five years would probably be 

sufficient to detect new threats and address the viability of the species. 

References

Flora of North America Editorial Committee. 2010. Flora of North America. 7:658 

Lotus mearnsii var. mearnsii 
51

Species overview

Lotus mearnsii var. mearnsii is a gray-green, low growing perennial herb 

with silvery pubescence. It is easily distinguished from its closest relative on the 

Forest, L. wrightii, by its long peduncles (inflorescence stalks), which greatly 

exceed the length of the leaves, distinct rachis of its pinnate leaves, and silvery 

(sericeous) pubescence. In contrast, the peduncles of L. wrightii are generally 

shorter than its leaves, the leaves appear digitate and appear green to yellowgreen, without silvery pubescence. Hybrids, however, have been reported 

between the two species in Yavapai and other counties (Kearney and Peebles 

1960). It should be noted that the much more rare variety, L. mearnsii var. 

mearnsii, occurs on Verde Formation just south of Yavapai County and should be 

sought on similar habitat within PNF. 

Life history

 Shoots of Lotus mearnsii var. mearnsii arise from deep-seated 

underground rhizomes and generally occur in small clones. This suggests that 

individuals may be long-lived. Flowers emerge between March and August. 

Distribution and abundance

 Lotus mearnsii var. mearnsii has a wide range from Arizona to New 

Mexico, ranging 700km. There are 84 occurrences listed in Seinet. In Arizona, L. 

mearnsii var. mearnsii, has 83 localities, ranging 610km; in south and central 

Cochise County, there are two occurrences, ranging 68km; in north, south, and 

central Coconino County, there are13 occurrences, ranging 214km; in north 

Maricopa County, there are seven occurrences, ranging 69km, in north and eastcentral Mohave County, there are five occurrences, ranging 227km; in south 

Navajo County, there are three occurrences, ranging 32km; in south and east 

Graham County, there are two occurrences, ranging 52km; in south Gila County, 

there is one occurrence; and in central Yavapai County, there are 50 

occurrences, ranging 145km. In New Mexico, L. mearnsii var. mearnsii, has one 

occurrence in south Hildago County. Thirteen occurrences for the taxon are wide 

spread over PNF, ranging 92km. 

Habitat

 Lotus mearnsii var. mearnsii occurs in streambeds and on various aspects 

of dry rocky slopes and ridgelines. Substrates include limestone, clay, 

calcareous sand, gravel, and deep sand. Elevation ranges between 985m 
52

(3231ft) and 1380m (4527ft) with a mean elevation of 1182m (3877ft). Vegetation 

types include piñon-Juniper woodland, blue grama grassland, and high desert 

grassland. 

Known and potential threats

 There are probably few threats to populations of Lotus mearnsii var. 

mearnsii within the Forest. Severe degradation of grasslands caused by overgrazing is probably the most viable threat, followed by off-road vehicle damage. 

Fire probably poses little danger to individuals of the taxon considering that the 

rhizomes probably survive the types of fires that occur in grasslands and 

woodlands. 

Recommended conservation strategies

 Because of the varied habitats and large geographical distribution of Lotus 

mearnsii var. mearnsii within PNF, the following recommended conservation 

might be considered a low priority with respect to efforts centering on more rare 

and potentially threatened species, at least until occasional monitoring suggests 

otherwise. 

1. Grazing management 

Although the nature of habitats for Lotus mearnsii var. mearnsii suggests that 

grazing could have a negative influence on populations, the rhizomatous nature 

and low habit of the taxon provides at least some resistance to grazing. The 

impact of grazing on populations of the taxon, however, may have more to do 

with its influence on the general health of the grassland rather than grazing of 

specific individuals. Since some populations do occur within the Verde 

Formation, efforts to protect that habitat would facilitate the efforts to enhance the 

viability of this species as well. Since the health of grasslands is of primary 

concern to the Forest, grassland management where populations of this taxon 

occur may be of particular concern. Perhaps it would be helpful to entertain the 

question as to whether Lotus mearnsii var. mearnsii, like Lesquerella cinerea is 

an indicator of healthy grassland, at least on certain soil types. In this respect, 

occasional monitoring would be very useful in determining the effects of grazing. 

1. Prevention of off-road vehicle traffic 

Off-road vehicle use is potentially the most damaging impact to populations of 

the taxon, especially where it causes erosion that leads to severe soil loss from 

habitats. Impacts of off-road vehicle use should be reviewed through initial 
53

monitoring efforts. See also the discussion of grasslands under grazing 

management. 

3. Fire management 

Although fire is probably not an important factor in considering the viability of the 

taxon, specific management decisions would be greatly facilitated by first 

monitoring selected populations. 

4. Surveys for new individuals 

Because of the rather large geographical distribution and variety of habitats of 

Lotus mearnsii var. mearnsii within PNF, there are probably sufficient populations 

to initiate monitoring of the species. 

Recommended monitoring

 Baseline data that record the presence or absence of impacts caused by 

grazing, browsing and other forms of herbivory; off-road vehicle use, weeds, fire, 

and other factors would be useful in determining better regime of conservation 

strategies. Although the interval of monitoring may also depend on baseline 

data, monitoring selected populations every three to five years would probably be 

sufficient to detect new threats and address the viability of the species. 

References

Kearney, Thomas H., and Robert H. Peebles. 1960. Arizona Flora. University of 

California Press, Berkeley, California. 

Lupinus latifolius var. leucanthus 

Species overview

 Although not strictly a wetland taxon as defined by the USDA, populations 

of Lupinus latifolius var. leucanthus within PNF nearly always occur along 

perennial streams or where the soil is wet all or most of the year. The stems are 

stout and often numerous from branched caudices. Healthy stands can be 

several meters broad and up to 2m tall. Unlike any of the other lupine species in 

the Forest, the flowers of Lupinus latifolius var. leucanthus are always nearly 

white with only a faint cast of color, except for a pale yellow-brown spot in the 

center of the upper petal (banner).
54

Life history

 Although probably a long-lived perennial, the delicate herbage (the mostly 

green stems and leaves) dies back in during the winter, then resprouts in the 

early spring and grows rapidly. Flowers emerge between May and July. 

Distribution and abundance

 Lupinus latifolius var. leucanthus occurs in southern Utah and in Mohave, 

Gila, and Yavapai counties, Arizona, with 18 occurrences listed in Seinet and 

seven localities listed from additional sources. Depending on the taxonomic 

treatment, there may also be populations in Nevada, New Mexico, and California. 

The total distribution range for L. latifolius var. leucanthus is 278 km; in southeast 

Mohave County, there are two occurrences, ranging less than 1km; in north and 

central Gila County, there are three occurrences, ranging 56km; and in central 

Yavapai County, there are 21 occurrences, ranging 82km. Nineteen occurrences 

for the species are wide spread over PNF, ranging 72km. 

Habitats

Populations of Lupinus latifolius var. leucanthus tend to occur on northfacing slopes, along streams, and near springs; with substrates including granite, 

granite cobble, and basalt. Elevation ranges between 1299m (4265ft) and 2099m 

(6889ft) with a mean elevation of 1699m (5577ft). Vegetation types include 

ponderosa pine forest, chaparral, mixed conifer forest, and riparian woodlands. 

Known and potential threats

 The primary threat to populations of Lupinus latifolius var. leucanthus is 

wetland degradation. Healthy populations of the taxon occur where there is a 

stable source of flowing water. Both drying of soil and severe flooding can kill 

entire stands. There is no evidence that grazing negatively affects plants and, 

because of the perennial nature of its underground stems, most fires probably do 

not kill individuals. Severe fires could kill stands by impacting wetland stability. 

Weed infestations are becoming an increasingly important problem within the 

Forest, especially along streams. Encroaching weeds, especially those with 

perennial rhizomes, are capable of crowding out native species. 
55

Recommended conservation strategies

 Because of the high correlation between healthy perennial streams and 

occurrences of Lupinus latifolius var. leucanthus, conservation strategies should 

focus on maintaining stability of perennial streams where populations of the 

taxon occur. Because streams are affected by influences to their entire 

watershed, the lower the habitat is downstream, the more area there is to 

manage. It this regard, focusing first on populations of Lupinus latifolius var.

leucanthus that occur in the upper reaches of channels, especially those that 

occur at or near springs may facilitate conservation efforts. 

 An iterative approach to the conservation of Lupinus latifolius var.

leucanthus populations is emphasized here because of the importance and 

dynamic nature of the wetland habitat. A cyclic regime of population 

assessment, monitoring, conservation efforts, and reassessment may be the only 

means of successfully insuring the viability of the taxon. 

1. Identification of manageable populations 

Using a GIS layer of known populations, sites could be prioritized as to their 

management practicability. Those populations, for example, higher in the 

watershed and occurring at springs might be assessed a higher priority. Ground 

truthing could then be used to further assess populations based on vigor and 

abundance of individuals, and nature of microhabitat. 

2. Fencing of springs 

The fencing of springs to prevent elk, cattle, and burros from denuding vegetation 

may help maintain flow within the spring itself and downstream. The protection 

of springs has many auxiliary benefits, including the protection of habitat for other 

important wetland flora and fauna that may include T&E animal species, 

increased availability of clean water downstream to cattle and native fauna, and 

enhanced recreational use. 

3. Fire management 

Reducing the risk of catastrophic fires within the surrounding watershed would 

also reduce the risk of catastrophic flooding. Catastrophic flooding not only kills 

individuals of Lupinus latifolius var. leucanthus but also often destroys habitat by 

altering topographic, downcutting channels, and removing perennial forbs and 

grasses that slow water flow. In this regard, control burns and other means of 

removing excess fuel in the watershed may facilitate the viability of the taxon. 

4. Grazing management 
56

Since heavy grazing can reduce plant cover and increase runoff, an assessment 

of the degree of grazing could improve watershed conditions. 

5. Revegetation 

Reseeding and replanting perennial forbs and grasses that have been lost or 

reduced by grazing, fire, and flooding may be a viable conservation strategy 

under certain conditions. In this regard, healthy watersheds that are similar with 

respect to topography, soil type, and elevation could be used to determine which 

plant species would be best used to revegetate an area of conservation concern. 

6. Weed removal 

There are several species of invasive weeds that are newly invading streams 

within PNF. Many of these may still be controllable. The identification and 

removal of populations of these weeds is of immediate importance, especially in 

areas of recent disturbance. 

Recommended monitoring

 Baseline data recorded from selected populations could be used to assess 

the presence or absence of impacts caused by grazing, browsing and other 

forms of herbivory; off-road vehicle use; weed infestation; fire; and other factors. 

Because of the somewhat volatile nature of stream habitat, yearly monitoring 

may be necessary to assess populations and their surrounding habitat. 

References

Arizona Game and Fish Department. 2005. Plant abstract for Lupinus latifolius 

var. leucanthus. Phoenix, Arizona. 

Mertensia macdougalii 

Species overview

Mertensia macdougalii is a glabrous gray-green perennial herb with showy 

purple-blue, pendent, funnelform flowers. The nutlets possess a distinct lobed 

margin (Kearney and Peebles 1960). Populations of this unique species are 

often widely-spaced, especially within PNF. It is an attractive plant and gardenworthy. Although seeds are available from Europe, it does not seem to be in 

general cultivation. 
57

Life history

 Although no information was found on the root system of Mertensia 

macdougalii, other species within the genus possess rhizomes. If this is also true 

of M. macdougalii, then it could be more long-lived than if it possessed a simple 

taproot. The flowers emerge between April and June. 

Distribution and abundance

 Mertensia macdougalii is endemic to Coconino, Maricopa, Mohave, Gila, 

and Yavapai counties, Arizona, with 72 occurrences listed in Seinet. The total 

distribution range for M. macdougallii is 404km; in south and central Coconino 

County there are 63 occurrences, ranging 211km; in central Maricopa County 

there is one occurrence; in north Mohave County there are two occurrences, 

ranging 67km; in north Gila County there is one occurrence; and in north and 

central Yavapai County there are five occurrences, ranging 104km. Three 

occurrences for the species are located in PNF, ranging 86km; one occurrence in 

the vicinity of Prescott, and two occurrences in the vicinity of the Santa Maria 

mountains located 53km northeast of Prescott.

Habitats

Populations of Mertensia macdougalii occur on south and southwestfacing slopes with substrates that include sandstone cobble, clay loam, and red 

soil, sand, and duff. Elevation ranges between 1300m (4265ft) and 2500m 

(8200ft) with a mean elevation of 2137m (7014ft). Vegetation types include 

Artemisia scrub, blue grama grassland, oak woodland, and pine forest. 

Individuals tend to occur in open areas with low plant cover. 

Known and potential threats

 Species within the family (Boraginaceae) generally do not possess many 

plant secondary compounds to ward off herbivores. In this regard, individuals of 

Mertensia macdougalii are probably susceptible to herbivory and grazing. Fire is 

prevalent in all habitats in which it occurs. At least some of its populations are 

accessible to off-road vehicles. 
58

Recommended conservation strategies

1. Grazing management 

Since known populations within PNF inhabit small widely spaced sites, 

exclosures could be a cost-effective means of protecting individuals of the 

species from grazing. It is unknown, however, if grazing negatively impacts 

populations and, therefore, conservation efforts in this regard would be best 

served after initial monitoring of populations. 

2. Fire management 

Habitats where populations of Mertensia macdougalii occur are subject to fire but 

any potential effects of fire on the species are undocumented. Prescribed 

burning may facilitate the maintenance of populations by reducing overstory and 

litter; and act as a deterrent to catastrophic fires. Initial and repeat monitoring 

may provide some insight into whether fire management would enhance the 

viability of this species within the Forest. 

2. Prevention of off-road vehicle traffic 

Off-road vehicle use is potentially damaging to populations of the taxon, 

especially where it causes erosion that leads to severe soil loss from habitats. 

Impacts of off-road vehicle use should be reviewed through initial monitoring 

efforts. 

4. Surveys for new individuals 

Because populations of Mertensia macdougalii occur in common, widespread 

habitats, specific surveys for additional populations may not be practical, except 

perhaps within the immediate areas of known populations. 

Recommended monitoring

 Baseline data that record the presence or absence of impacts caused by 

grazing, browsing and other forms of herbivory; off-road vehicle use, weeds, fire, 

and other factors would be useful in determining better regime of conservation 

strategies. Although the interval of monitoring may also depend on baseline 

data, monitoring selected populations every three to five years would probably be 

sufficient to detect new threats and address the viability of the species. 
59

References

Kearney, Thomas H., and Robert H. Peebles. 1960. Arizona Flora. University of 

California Press, Berkeley, California. 

Pediomelum mephiticum 

Species overview

 Apparently, at least some, if not all populations of Pediomelum within PNF 

now belong to a newly described and more rare species, P. verdiensis (Welsh & 

Licher 2010). Both P. mephiticum and P. verdiensis are low perennial herbs from 

a deep, vertical, tuberous taproot. 

Life history

 Because of the large size of their taproot, individuals are probably longlived. The flowers emerge between April and June, and again after summer 

rains. 

Distribution and abundance

 Pediomelum mephiticum has a wide range from Arizona to Utah and 

Nevada, ranging 643km. There are 82 occurrences listed in Seinet. In Arizona, 

P. mephiticum, has 52 occurrences, ranging 448km; in south Apache County, 

there is one occurrence; in north and south Coconino County, there are four 

occurrences, ranging 249km; in central Gila County, there is one occurrence; in 

north and east Maricopa County, there are two occurrences, ranging 122km; in 

north and central Mohave County, there are 32 occurrences, ranging 225km; and 

in north Yavapai County, there are 12 occurrences, ranging 77km. In New 

Mexico, P. mephiticum, has 14 occurrences, ranging 457km; along the eastern 

border of Grand County, there is one occurrence, and throughout Washington 

County, there are 13 occurrences, ranging 90km. In Nevada, P. mephiticum, has 

one occurrence in central Lincoln County. The remaining 17 occurrences have 

insufficient locality data. Eight occurrences for the species spread over PNF, 

ranging 107km. Although herbarium specimens annotated by the authors of P. 

verdiensis were collected primarily from the Verde Formation in the Verde Valley, 

there were at least two collections annotated as P. verdiensis from near 

Perkinsville (Welsh & Licher 2010). 
60

Habitats

Populations of Pediomelum mephiticum tend to occur on south-facing 

slopes, in open areas, and near drainages; with substrates including calcareous, 

sand, gravely limestone, gravely-loam, and basalt. Elevation ranges between 

1542m (5000ft) and 1667m (5500ft) with a mean elevation of 1596m (5230ft). 

Vegetation types include desert foothills, Sonoran desert scrub, juniper-piñon 

pine woodlands, and Great Basin conifer forest. 

Known and potential threats

 There are probably few threats to populations of Pediomelum mephiticum

within the Forest. Severe degradation of habitats caused by over-grazing is 

probably the most viable threat, followed by off-road vehicle damage. Fire 

probably poses little danger to individuals of the taxon considering that the 

rhizomes probably survive the types of fires that occur in grasslands and 

woodlands. 

Recommended conservation strategies

 At least some of the known populations occur on the Verde Formation 

those populations could be included in the umbrella protection of that habitat. 

1. Taxonomic identification of populations 

Because of the new taxonomic circumscription of the populations within PNF, it 

would be impractical to implement conservation strategies until each known 

population is identified as to which species it belongs. This might simply be done 

by reviewing herbarium material, much of which has already been annotated by 

the authors of P. verdiensis. 

2. Surveys for new individuals 

Because neither species has been on a target species list during rare plant 

surveys, at least in the areas where they occur, additional populations might 

easily be found with minimum effort. Surveys within the general area of 

occurrence in the Forest would help determine a better estimate of individuals. 

Because new individuals may be found, this may be an important step prior to 

any further conservation or monitoring efforts. 

3. Grazing management 
61

Although the nature of habitats for Pediomelum mephiticum suggests that 

grazing could have a negative influence on populations, the rhizomatous nature 

and low habit of the taxon provides at least some resistance to grazing. 

4. Prevention of off-road vehicle traffic 

Off-road vehicle use is potentially the most damaging impact to populations of 

the either taxon, especially where it causes erosion that leads to severe soil loss 

from habitats. Impacts of off-road vehicle use should be reviewed through initial 

monitoring efforts. 

5. Fire management 

Although fire is probably not an important factor in considering the viability of the 

taxon, specific management decisions would be greatly facilitated by first 

monitoring selected populations. 

Recommended monitoring

 Baseline data that record the presence or absence of impacts caused by 

grazing, browsing and other forms of herbivory; off-road vehicle use, weeds, fire, 

and other factors would be useful in determining better regime of conservation 

strategies. Although the interval of monitoring may also depend on baseline 

data, monitoring selected populations every three to five years would probably be 

sufficient to detect new threats and address the viability of the species. 

References

Kearney, Thomas H., and Robert H. Peebles. 1960. Arizona Flora. University of 

California Press, Berkeley, California. 

Welsh, S. L. and M. Licher. 2010. Pediomelum Rydberg (Leguminosae) in 

Arizona and two previously undescribed species. Western North American 

Naturalist 70(1):9-18. 

Phlox amabilis 

Species overview

Phlox amabilis is a low perennial herb with showy pink flowers. It is 

probably common in PNF but the ambiguity of the taxonomy of it and its close 
62

relatives makes identification very difficult. It differs from its closest relative only 

in the length of its stamens and styles. 

Life history

 It is not clear if individuals of Phlox amabilis possess a taproot or spread 

by rhizomes. It is possible that young plants possess taproots and develop 

rhizomes afterwards. The flowers emerge between March and May. 

Distribution and abundance

 Phlox amabilis is endemic to Coconino, Maricopa, Mohave, and Yavapai 

counties, Arizona, with 52 occurrences listed in Seinet. The total distribution 

range for P. amabilis is 371km; throughout Coconino County, there are 17 

occurrences, ranging 274km; in north Maricopa County, there is on occurrence; 

in north central Mohave County, there are seven occurrences, with a range of 

162km; and throughout Yavapai County, there are 27 occurrences, ranging 

131km. Nine occurrences for the species spread over PNF, ranging 74km. 

Habitats

Populations of Phlox amabilis tend to occur on north, west, and eastfacing slopes and in open areas; with substrates that include limestone, 

fosslilferous chert, basalt, and granite. Elevation ranges between 1078m (3500ft) 

and 2734m (8970ft) with a mean elevation of 1960m (6430ft). Vegetation types 

include pine-juniper woodland, riparian areas, and deserts. 

Known and potential threats

 Most populations of Phlox amabilis are recorded from habitats where fire 

is common but the effects of fire on the species are unknown. Being primarily 

herbaceous, plants are probably grazed by cattle. There is some potential from 

ORV activity. 

Recommended conservation strategies

1. Identification criteria 
63

Because the species appears morphological similar to its closest relatives, 

several of which are also recorded for the Forest, good diagnostic descriptions, 

including photographs would enable personnel to more easily identify the 

species. Special attention should be paid to underground parts and longitudinal 

sections of flowers. The type locality is near Prescott and should be sampled, 

along with several nearby populations in order to document morphological 

variation within the species. 

2. Surveys for new individuals 

Surveys for the species within in the Forest would help ascertain the presence of 

any additional populations. Because Phlox amabilis is apparently common, at 

least in the vicinity of Prescott, finding new populations may take a minimum 

amount of effort. Additional populations would greatly aid determining the 

taxonomic status and validity of the species, as well as facilitating the continued 

viability of the species, assuming it is valid. 

3. Fire management 

Habitats where Phlox amabilis occurs are subject to fire but the effects of fire on 

the species are undocumented. Initial and repeat monitoring may provide some 

insight into whether fire management would enhance the viability of this species. 

4. Grazing management 

Although the habitat for this species suggests that grazing probably does not 

impart a negative influence on populations, impacts of grazing should be tested 

through initial monitoring efforts. 

5. Prevention of off-road vehicle traffic 

As with grazing, this species occurs within habitats where off-road travel would 

not generally affect plants. 

Recommended monitoring

 Baseline data that record the presence or absence of impacts caused by 

grazing, browsing and other forms of herbivory; off-road vehicle use, weeds, fire, 

and other factors would be useful in determining better regime of conservation 

strategies. The interval of monitoring may also depend on baseline data. For 

example, if individuals of Phlox amabilis appear to be healthy with no impacts, 

then monitoring could probably done less frequently. 
64

References

Arizona Game and Fish Department. 2005. Plant abstract for Phlox amabilis. 

Phoenix, Arizona. 

Kearney, Thomas H., and Robert H. Peebles. 1960. Arizona Flora. University of 

California Press, Berkeley, California. 

Polygala rusbyi 

Species overview

Polygala rusbyi is a unique species; a low perennial with several short 

stems from deep-seated rhizomes. It differs from the other species in our area 

by its habit, rather wide pilose leaves, and large purple flowers with a yellow 

beak. It should be noted that its rhizomes are not described in the literature 

(Arizona Game and Fish Department 2003, Kearney & Peebles 1960). The 

flowers emerge between April and July. 

Life history

 Because of their deep rhizomes, individuals of Polygala rusbyi are 

probably long-lived in spite of the small size of their shoots. The flowers emerge 

between April and July. 

Distribution and abundance

 Polygala rusbyi is endemic to Maricopa, Mohave, and Yavapai counties, 

Arizona, with 83 occurrences listed in Seinet and eight localities from additional 

sources. The total distribution range for P. rusbyi is 382 km; in north Maricopa 

County, there are four occurrences, ranging 24km; in central Mohave County, 

there are five occurrences, ranging 31km; and in northeast and central Yavapai 

County, there are 78 occurrences, ranging 164km. Twenty occurrences for the 

species are spread over PNF, ranging 81km; there are six occurrences in the 

vicinity of Cottonwood and 14 in the vicinity of Paulden. 

Habitats

Populations of Polygala rusbyi tend to occur on ridge tops and open 

mesas; with substrates including powdery gypsiferous limestone of tertiary 
65

lakebed deposits (Verde Formation), red-wall limestone, and limestonesandstone. Elevation ranges between 1000m (3280ft) and 1500m (4921ft) with a 

mean elevation of 1250m (8200ft). Vegetation types include pine-juniper 

woodlands and semi-desert shrub. 

Known and potential threats

 There are probably few threats to populations of Polygala rusbyi within the 

Forest. Severe degradation of grasslands caused by over-grazing is probably the 

most viable threat, followed by off-road vehicle damage. Fire probably poses 

little danger to individuals of the taxon considering that the rhizomes probably 

survive the types of fires that occur in grasslands and woodlands. At least some 

populations of the species occur in areas of the Verde Formation and thus should 

be included within the conservation of that habitat. 

Recommended conservation strategies

 Because of the varied habitats and large geographical distribution of 

Polygala rusbyi within PNF, the following recommended conservation might be 

considered a low priority with respect to efforts centering on more rare and 

potentially threatened species, at least until occasional monitoring suggests 

otherwise. 

1. Grazing management 

Although the nature of habitats for Polygala rusbyi suggests that grazing could 

have a negative influence on populations, the rhizomatous nature and low habit 

of its individuals provide at least some resistance to grazing. The impact of 

grazing on populations of the taxon, however, may have more to do with its 

influence on the general health of the grassland rather than grazing of specific 

individuals. Since the health of grasslands is of primary concern to the Forest, 

grassland management where populations of this taxon occur may be of 

particular concern. Perhaps it would be helpful to entertain the question as to 

whether Polygala rusbyi, like Lotus mearnsii var. mearnsii and Lesquerella 

cinerea, is an indicator of healthy grassland, at least on certain soil types. In this 

respect, occasional monitoring would be very useful in determining the effects of 

grazing. 

1. Prevention of off-road vehicle traffic 

Off-road vehicle use is potentially the most damaging impact to populations of 

the species, especially where it causes erosion that leads to severe soil loss from 

habitats. Impacts of off-road vehicle use should be reviewed through initial 
66

monitoring efforts. See also the discussion of grasslands under grazing 

management. 

3. Fire management 

Although fire is probably not an important factor in considering the viability of the 

species, specific management decisions would be greatly facilitated by first 

monitoring selected populations. 

4. Surveys for new individuals 

Because of the rather large geographical distribution and variety of habitats of 

Polygala rusbyi within PNF, there are probably sufficient populations to initiate 

monitoring of the species. 

Recommended monitoring

 Baseline data that record the presence or absence of impacts caused by 

grazing, browsing and other forms of herbivory; off-road vehicle use, weeds, fire, 

and other factors would be useful in determining better regime of conservation 

strategies. Although the interval of monitoring may also depend on baseline 

data, monitoring selected populations every three to five years would probably be 

sufficient to detect new threats and address the viability of the species. 

References

Arizona Game and Fish Department. 2003. Plant abstract for Polygala rusbyi. 

Phoenix, Arizona. 

Kearney, Thomas H., and Robert H. Peebles. 1960. Arizona Flora. University of 

California Press, Berkeley, California. 

Salvia dorrii var. mearnsii 

Species overview

Salvia dorrii var. mearnsii is a handsome shrub with savory, gray-green 

leaves and rather showy pale purple flowers. Often individuals are stunted with 

old, twisted stems giving the plants a bonsai appearance. The taxon differs from 

its closest relative, Salvia dorrii var. mearnsii, by its much wider leaves. 
67

Life history

 Individuals of Salvia dorrii var. mearnsii give the appearance of being very 

old. Individuals in cultivation in Chino Valley, thus far, have lived over ten years 

in pots. Flowers emerge between April and May. 

Distribution and abundance

 Salvia dorrii var. mearnsii is endemic to Yavapai County, Arizona, with 31 

occurrences listed in Seinet and 43 localities from additional sources. The total 

distribution range for S. dorrii var. mearnsii is 68 km; with 38 occurrences of the 

species spread over PNF ranging 62km; 29 occurrences are in the vicinity of 

Paulden and nine occurrences are in the vicinity of Cottonwood. 

Habitats

Individuals of the species tend to occur on various aspects of rocky slopes and 

ridgelines; with substrates including Limestone, sandstone, tan soil, Verde 

Formation, and Calcareous ridge tops. Elevation ranges between 1000m (3280ft) 

and 1500m (4921ft) with a mean elevation of 1250m (8200ft). Vegetation types 

include Pinus edulis-Juniperus woodlands, and semi-desert shrub. 

Known and potential threats

 Since individuals are restricted to the Verde Formation and certain other 

soils, primarily with a mixture of sandstone and limestone alluvium, the areas in 

which plants occur are restricted geographically. Plant densities tend to be low 

on these soils, with few large shrubs and cacti, making the sites attractive to offroad vehicles. Apparently, plants do not grow back in areas where surface 

disturbance has occurred (Arizona Game and Fish Department 2002). Individuals 

of the taxon do not appear palatable to livestock and no direct impacts from cattle 

have been recorded. Also, since cover is low within these soils, cattle do not 

seems to linger long enough to cause much damage. No damage from fire has 

been reported for the species 

Recommended conservation strategies

 Like other taxa that occur on the Verde Formation, conservation of habitat 

is of primary concern to the viability of the populations. For a more detailed 

account of the Verde Formation, see page 59. 
68

1. Prevention of off-road vehicle traffic 

Impediments to off-road use in areas where individuals of the taxon occurs are of 

primary importance. Closing two-tracks and minor Forest roads with large 

boulders and/or other vehicle-proof structures at access points may be effective 

in this regard. Signs suggesting alternate and legal ORV areas in the vicinity 

may be useful. 

2. Surveys for new individuals 

Surveys within areas where appropriate soils occur in the Forest would help 

ascertain the presence of any additional populations. Since much of the potential 

habitat for the taxon has been surveyed, at least within PNF, survey efforts may 

be minimal. Also, surveys for individuals of this taxon can be conducted 

concurrently with those for other taxa that occur within similar habitats. 

3. Fire management 

Although historically habitats within the Verde Formation and other soils where 

Salvia dorrii var. mearnsii occur are not subject to fire, in years where non-native 

weeds, such as Bromus rubens (cheatgrass), are abundant, fire may be a 

problem. During such years, removal of weeds near individuals of Salvia dorrii 

var. mearnsii may be preventative. 

4. Grazing management 

Until such time as negative grazing efforts are record for individuals of the taxon, 

conservation efforts centering on grazing management are not recommended. 

Recommended monitoring

Baseline data that recorded the presence or absence of impacts caused by 

grazing, browsing and other forms of herbivory; off-road vehicle use, weeds, fire, 

and other factors would be useful in determining better regime of conservation 

strategies. The interval of monitoring may also depend on baseline data. For 

example, if individuals of Salvia dorrii var. mearnsii appear to be healthy with no 

impacts, then monitoring could probably done less frequently. 

References

Arizona Game and Fish Department. 2002. Plant abstract for Salvia dorrii var. 

mearnsii. Phoenix, Arizona. 

Kearney, Thomas H., and Robert H. Peebles. 1960. Arizona Flora. University of 

California Press, Berkeley, California. 
69

Sporobolus interruptus 

Species overview

Sporobolus interruptus is a handsome bunchgrass with short rhizomes 

that is rarely seen within PNF. The evolutionary biology of the species is 

confusing in that it is thought to be a triploid suggesting plants are sexually 

sterile. If this is true, then the species is clonal, producing seeds apomictically. 

Often, triploids are products of hybridization, which would help explain the 

infrequent occurrence of populations. There is no mention, however, in the Flora 

of North America of this possibility and there are no other rhizomatous species of 

Sporobolus in our area (Flora of North America Editorial Committee. 2010). 

Life history

 The presence of rhizomes suggests that individuals of Sporobolus 

interruptus may be longer-lived than at least some dropseeds, such as S. 

cryptandrus. However, it is probably not as long-lived as the more robust 

dropseeds, such as S. arioides. Flowers emerge between July and October. 

Distribution and abundance

 Sporobolus interruptus is endemic to Apache, Coconino, Gila, Maricopa, 

Navajo, and Yavapai counties, Arizona, with 83 occurrences listed in Seinet. The 

total distribution range for S. interruptus is 378km; in south Apache County, there 

are two occurrences, ranging 4km; throughout Coconino County, there are 55 

occurrences, ranging 244km; in north and central Gila County, there are twelve 

occurrences, ranging 133km; in west Maricopa County, there is one occurrence; 

and in south and central Yavapai County, there are six occurrences, ranging 

84km. The remaining seven occurrences have insufficient locality data. There are 

five occurrences for the species spread over PNF, ranging 36km. 

Habitats

Populations of Sporobolus interruptus tend to occur on southwest-facing 

slopes, mesa tops, and flat exposures; with substrates that include basalt, clay 

loam, and limestone. Elevation ranges between 1090m (3576ft) and 2340m 

(7677ft) with a mean elevation of 1750m (5741ft). Vegetation types include 

pine/juniper forest, oak woodland, and Poa pratensis grassland. 
70

Known and potential threats

Sporobolus interruptus is highly relished by livestock (United States 

Department of Agriculture 1937) and fire is prevalent in all habitats in which it 

occurs. The presence of rhizomes, however, may offer some resistance to both 

grazing and fire impacts. At least some of its populations are accessible to offroad vehicles. 

Recommended conservation strategies

1. Grazing management 

Since known populations within PNF inhabit small widely spaced sites, a limited 

degree of grazing management might be needed to insured their continued 

viability. Limiting grazing on sites where the species occurs until after plants 

have set seed might be effective. Any more drastic conservation measures 

should probably wait until at least some monitoring of populations has been 

done. 

2. Fire management 

Habitats where populations of Sporobolus interruptus occur are subject to fire but 

any potential effects of fire on the species are undocumented. Most species of 

the genus respond well to occasional fires. Prescribed burning may facilitate the 

maintenance of populations by reducing overstory and litter and act as a 

deterrent to catastrophic fires. Initial and repeat monitoring may provide some 

insight into whether fire management would enhance the viability of this species 

within the Forest. 

2. Prevention of off-road vehicle traffic 

Off-road vehicle use is potentially damaging to populations of the taxon, 

especially where it causes erosion that leads to severe soil loss from habitats. 

Impacts of off-road vehicle use should be reviewed through initial monitoring 

efforts. 

4. Surveys for new individuals 

Because habitats where Sporobolus interruptus occurs are common and 

widespread, specific surveys for additional populations may not be practical, 

except perhaps within the immediate areas of known populations. 
71

Recommended monitoring

 Baseline data that record the presence or absence of impacts caused by 

grazing, browsing and other forms of herbivory; off-road vehicle use, weeds, fire, 

and other factors would be useful in determining better regime of conservation 

strategies. Although the interval of monitoring may also depend on baseline 

data, monitoring selected populations every three to five years would probably be 

sufficient to detect new threats and address the viability of the species. 

References

Flora of North America Editorial Committee. 2003. Flora of North America. 

25:133-134. 

United States Department of Agriculture. 1937. Range Plant Handbook. United 

States Government Printing Office, Washington, DC 

Triteleia lemmoniae 

Species overview

Triteleia lemmoniae a unique scapose perennial herb with bright yellow to 

orange turbinate flowers. It has 1-3 basal, grass-like leaves to 40cm long and is 

the only species of the genus in Arizona. Although it is most similar 

mophologically to T. hyacinthina, which occurs in the northwestern U. S., 

molecular data suggest that it is related to T. montana, which occurs in the Sierra 

Nevada of California. (Flora of North America Editorial Committee. 2002) 

Life history

 Leaves and flowering shoots emerge in the spring from a fibrous-coated 

corm similar to many native onions. Flowers open between May and August. 

Distribution and abundance

Triteleia lemmoniae is endemic to Coconino, Gila, Navajo, and Yavapai 

counties, with 41 occurrences listed in Seinet. Its total distribution range is 

221km; in south and southeast Coconino County, there are 23 occurrences, 

ranging 231km; in north and west Gila County, there are thirteen occurrences, 

ranging 70km; in south Navajo County, there is one occurrence; and in southcentral Yavapai County, there is one occurrence. The remaining three 
72

occurrences have insufficient locality data to map. There are no occurrences in 

PNF but there are two records within 2km of the northern boundary at Lake 

Pocket. 

Habitats

Populations of Triteleia lemmoniae occur in open areas, near ponds, and 

on rocky hillsides; with substrates that include sandstone and volcanic soils. 

Elevation ranges between 980m (3215ft) and 2340m (7677ft) with a mean 

elevation of 1660m (5446ft). Vegetation types are pine and oak woodlands. 

Known and potential threats

 Because of its habit, Triteleia lemmoniae is probably not directly effected 

by either grazing or fire. Its leaves are inconspicuous and somewhat hidden 

among other herbs and grasses. Also the bulk of its energy stores are in the 

underground corm, which is protected from grazing and most fires. Impacts from 

fire and grazing, therefore, would primarily occur when they lead to soil damage 

and severe reduction in the amount of herbaceous cover. Some populations of 

the species are probably accessible to off-road vehicles. 

Recommended conservation strategies

1. Surveys for populations within Prescott National Forest 

Because there are no populations of the species within the Forest boundaries, 

surveys specific to the species must be conducted in order to ascertain if 

populations do occur within the Forest. Because of the apparent common nature 

of habitats for Triteleia lemmoniae, it may prove most efficient to begin surveys in 

the general areas where populations are known. 

2. Grazing management 

Impacts of grazing on populations of Triteleia lemmoniae may probably has more 

to do with their influence on the general health of the grassland rather than 

grazing of specific individuals. Since the health of grasslands is of primary 

concern to the Forest, grassland management where populations of this taxon 

occur may be of additional concern. For example, recruitment of individuals may 

be facilitated by limiting grazing until after plants have set seed. More drastic 

conservation measures should probably wait until at least some monitoring of 

populations has been done. 
73

3. Fire management 

Habitats where populations of Triteleia lemmoniae occur are subject to fire but 

any potential effects of fire on the species are undocumented. Prescribed 

burning may facilitate the maintenance of populations by reducing overstory and 

litter; and act as a deterrent to catastrophic fires. Initial and repeat monitoring 

may provide some insight into whether fire management would enhance the 

viability of this species within the Forest. 

4. Prevention of off-road vehicle traffic 

Off-road vehicle use is potentially damaging to populations of the taxon, 

especially where it causes erosion that leads to severe soil loss from habitats. 

Impacts of off-road vehicle use should be reviewed through initial monitoring 

efforts. 

Recommended monitoring

 Baseline data that record the presence or absence of impacts caused by 

grazing, browsing and other forms of herbivory; off-road vehicle use, weeds, fire, 

and other factors would be useful in determining better regime of conservation 

strategies. Although the interval of monitoring may also depend on baseline 

data, monitoring selected populations every three to five years would probably be 

sufficient to detect new threats and address the viability of the species. 

References

Arizona Game and Fish Department. 2004. Plant abstract for Triteleia 

lemmoniae. Phoenix, Arizona. 

Flora of North America Editorial Committee. 2002. Flora of North America. 

26:345. 
74

Part 3. Habitats of Special Concern 

Verde Formation

 Because of the particular importance of the Verde Formation habitats with 

respect to rare species within the Forest, threats to this habitat and conservation 

recommendations are presented in more detail below. 

 

 The Verde Formation is composed of tertiary lake bed deposits of 

powdery calcareous and gypseous soils from secondary deposition of limestone 

and dolomite alluvium, often mixed with red-brown clayey and sandy soils. Areas 

of Verde Formation within PNF are limited both in acreage and geography and 

occur along the easternmost boundary of the Forest. Outside the Forest, the 

Verde Formation habitat is threatened by gypsum quarries, urban development, 

utility right-of-ways, and off-road vehicle use. Some combination of these threats 

probably exists on Forest. 

A list of taxa of conservation concern known to occur on Verde Formation habitat 

within PNF is provided in Table 4. 

Table 4. Vascular plant taxa of conservation concern known to occur on Verde Formation 

habitat within PNF. All species listed are considered here an immediate viability concern. 

Taxon Common name 

Occurs only on Verde 

Formation, at least within 

PNF? 

Anulocaulis leiosolenus var. 

leiosolenus 

Southwestern ringstem Yes 

Eriogonum ripleyi Ripley's wild-buckwheat Yes 

Eriogonum ericifolium (E. ericifolium

var. ericifolium) 

Heathleaf wild 

buckwheat 

Yes 

Eriogonum arizonicum Arizona wild-buckwheat No, occurs in similar soil 

types over a large range 

Lesquerella cinerea (Physaria cinerea) Basin bladder-pod No, also occurs in other 

limestone soils 

Lotus mearnsii var. mearnsii Mearns lotus No, also occurs in other 

limestone soils 

Pediomelum mephiticum 

P. verdiensis 

Skunk-top scurfpea 

Verde breadroot 

No, although the newly 

described species, P. 

verdiensis is mostly limited 

to the Verde Formation 

Polygala rusbyi Hualapai milkwort No, also occurs in other 

limestone soils 

Salvia dorrii ssp. mearnsii Mearns sage No but occurs on similar 

soils to the west 
75

Recommended conservation strategies

1. Prevention of off-road vehicle traffic 

Impediments to off-road use in areas of the Verde Formation is of primary 

conservation concern. Soils within the Verde Formation are loose and fragile. 

Vehicles tend to make deep and lasting tracks and vegetation is easily uprooted. 

The closure of two-tracks and minor Forest roads in the vicinity of the Verde 

Formation might solve the problem. Because Forest visitors do not always obey 

signs, blocking access with large boulders and/or other vehicle-proof structures 

at access points may be necessary. A single off-road vehicle could cause 

damage that might take decades to heal. In addition, signs posted at block roads 

that suggest alternate and legal ORV areas in the vicinity may a viable deterrent. 

2. Conservation designation 

Any conservation designation that would reduce the risk of gypsum mines, pipelines, power poles, and other projects that would severely disturb habitats within 

the Verde Formation would provide additional protection for rare species that 

occur there. 

3. Grazing management 

Although restricting cattle grazing may benefit populations of the rare taxa that 

occur within the Verde Formation, wasted efforts in this regard may be avoided if 

rare plant populations are first monitored in order to ascertain if grazing by both 

cattle an elk is indeed a negative influence. If grazing is a problem, then perhaps 

the areas could be excluded from the grazing allotment by exclosures. If grazing 

by elk is also of concern, then stronger fencing would be required. 

4. Weed management 

The spread of invasive plants species is an increasing throughout the Forest. It 

may be of particular concern on the loose soils of the Verde Formation. For 

example, two species of invasive exotic species have recently become a problem 

within soils of the Verde Valley. One of these, Centaurea solstitialis (yellow 

starthistle), is a spiny cool season annual with bright yellow flowers. It can be 

fatal horses that feed on it. The other species, Centaurea diffusa (diffuse 

knapweed) is generally a biennial with white to lavender flowers. Both species, 

one established can be very difficult to eradicate and can severely alter the 

ecology of an infested area. Fortunately, both of the aforementioned weeds do 

not possess rhizomes and can be easily pulled out. Eradication, however, takes 

repeated treatments over several years. Probably the best management advice 

would be to try to catch infestations early on. 
76

5. Fire management 

Although historically habitats within the Verde Formation are not subject to fire, in 

years where non-native weeds, such as Bromus rubens (cheatgrass), are 

abundant, fire may be a problem. During such years, removal of such weeds 

from critical areas may be preventative. 

Recommended monitoring

 Because populations of several rare taxa occur within the Verde 

Formation, monitoring of several of these populations could be done 

concurrently. Recommended frequency of monitoring would, of course, depend 

on the types of impacts detected during initial data collection. Data collected 

should include date of collection, time of day, GPS coordinates of individuals or 

at least populations; numbers of individuals; size of individuals; stage of 

maturation; state of phenology (buds, flowers, fruits); overall herb cover; overall 

shrub and tree cover; percent covers of duff, soil, cobbles, rocks, boulders, and 

bedrock; presence of weed species, types of human impacts, signs of herbivory 

and disease, signs of grazing and associated impacts, signs of fire and 

associated impacts, and signs of flooding and/or erosion and associated impacts. 

Part 4. Species Viability Summaries 

Associated Habitats 

A summary of all vascular plant species of viability concern and their associated 

habitats within Prescott National Forest boundaries is provided in Table 5. 

Risk Factors 

An overview of their risk factors is presented in Table 6. 

Viability Ratings 

Tables 7, 8, and 9 list the plant species by low, moderate and high at-risk 

viability. For the species that are at low risk for viability, the implementation of 

coarse filter plan components (e.g. desired conditions that apply to all vegetation 

types) should assure their continued viability. For species that are at moderate or 

high risk for viability, additional fine filter plan components (standards, guidelines) 

are necessary to assure their continued viability. Specific coarse and fine filter 

plan components are listed after each table. 
77

Table 5. Vascular plant species of viability concern and their associated habitats within Prescott National Fore

Taxon 

Habitat type 

Grasslands, 

including P- J 

grasslands 

Ponderosa Pine 

and Douglas Fir 

Forests 

Riparian and 

springs 

Moist, northfacing slopes 

Rock cliffs, 

ledges, and 

outcroppings 

Verde 

Formation 

Calcareous 

alluvial soils, 

except Verde 

Formation 

Cobbly ridges 

and hillsides 

Agave phillipsiana Mostly Agave delamateri Mostly Anulocaulis leiosolenus Mostly Arenaria aberrans Mostly Astragalus troglodytus Mostly Cystopteris utahensis Mostly Mostly Desmodium metcalfei Mostly Mostly Eriogonum ericifolium Always Eriogonum arizonicum Often Often Eriogonum ripleyi Mostly Often Hedeoma diffusum Mostly Often Mostly Heuchera novamexicana Mostly Heuchera eastwoodiae Mostly Mostly Lesquerella cinerea Often Often Often Lesquerella pinetorum Mostly Often Lotus mearnsii var. mearnsii Often Often Often Lupinus latifolius ssp. 

leucanthus 

 Mostly Possibly 

Mertensia macdougalii Often Often Often Pediomelum mephiticum Often Often Often Often Pediomelum verdiensis Mostly Phlox amabilis Often Often Often Polygala rusbyi Mostly Mostly Often Salvia dorrii ssp. mearnsii Often Often Often Sporobolus interruptus Often Often Triteleia lemmoniae Possibly Possibly 
78

Table 6. Vascular plant species of viability concern and their associated risk factors within Prescott National F

Taxon 

Risk Factors 

Off-road 

vehicle traffic 

Grazing 

Mining 

Fire 

Logging, 

thinning 

Weed 

invasion 

Flooding 

Cllti

Agave phillipsiana Negative Unknown Negative Unknown Neutral Negative Neutral UAgave delamateri Negative Unknown Negative Unknown Neutral Negative Neutral UAnulocaulis leiosolenus Negative Negative Negative Unknown Neutral Negative Neutral NArenaria aberrans Negative Unknown Negative Unknown Unknown Negative Neutral NAstragalus troglodytus Negative Unknown Negative Unknown Unknown Negative Neutral NCystopteris utahensis Unknown Neutral Unknown Unknown Unknown Negative Neutral NDesmodium metcalfei Negative Unknown Negative Unknown Unknown Negative Unknown NEriogonum ericifolium Negative Unknown Negative Unknown Neutral Negative Neutral NEriogonum arizonicum Negative Unknown Negative Unknown Neutral Negative Neutral NEriogonum ripleyi Negative Unknown Negative Unknown Neutral Negative Neutral NHedeoma diffusum Negative Unknown Negative Unknown Unknown Negative Neutral NHeuchera novamexicana Negative Unknown Negative Unknown Unknown Negative Neutral NHeuchera eastwoodiae Negative Unknown Negative Unknown Unknown Negative Neutral NLesquerella cinerea Negative Unknown Negative Unknown Neutral Negative Neutral NLesquerella pinetorum Negative Unknown Negative Unknown Unknown Negative Neutral NLotus mearnsii var. mearnsii Negative Unknown Negative Unknown Neutral Negative Neutral NLupinus latifolius ssp. 

leucanthus 

Negative Unknown Negative Unknown Unknown Negative Negative N

Mertensia macdougalii Negative Unknown Negative Unknown Unknown Negative Neutral NPediomelum mephiticum / Pediomelum verdiensis 

Negative Unknown Negative Unknown Neutral Negative Neutral N

Phlox amabilis Negative Unknown Negative Unknown Neutral Negative Neutral NPolygala rusbyi Negative Unknown Negative Unknown Neutral Negative Neutral NSalvia dorrii ssp. mearnsii Negative Unknown Negative Unknown Neutral Negative Neutral NSporobolus interruptus Negative Unknown Negative Unknown Unknown Negative Neutral NTriteleia lemmoniae Negative Unknown Negative Unknown Unknown Negative Neutral N
79

Table 7. List of Vascular Plants on the Prescott NF having Low Risk to Viability. 

Name Status Known Populations Habitat Association Viability Risk Factors Viability Risk Plan c

Tonto Basin Agave 

(Agave delamateri) S 

Coconino County: 4 

Yavapai County: 36 

PNF: 5 

Cobbly ridges/ hills Fire Low 

Coa

Desire

Phillips' Agave 

(Agave phillipsiana) S 

Coconino County: 15 

Yavapai County: 21 

PNF: 12 

Cobbly ridges/ hills Fire Low 

Mt. Dellenbaugh Sandwort 

(Arenaria aberrans) S 

Coconino County: 7 

Yavapai County: 13 

PNF: 6 

Moist, north-facing 

slopes Fire Low 

Creeping Milkvetch 

(Astragalus troglodytus) O 

Coconino County: 42 

Yavapai County: 10 

PNF: 3 

Grasslands No known threats Low 

Utah Bladder Fern (Cystopteris 

utahensis) O 

Coconino County: 25 

Yavapai County: 1 

PNF: 1 

Rock cliffs & ledges No known threats Low 

Metcalfe's Ticktrefoil 

(Desmodium metcalfei) S 

Coconino County: 1 

Yavapai County: 1 

PNF: 1 

Ponderosa pine forests No known threats Low 

Flagstaff Pennyroyal (Hedeoma 

diffusum) S 

Coconino County: 43 

Yavapai County: 20 

PNF: 2 

Rock cliffs & ledges Weed invasion Low 

Eastwood Alum-root (Heuchera 

eastwoodiae) S 

Coconino County: 1 

Yavapai County: 43 

PNF: 33 

Moist, north-facing 

slopes Fire Low 

New Mexico Alum-root 

(Heuchera novomexicana) O 

Coconino County: 3 

Yavapai County: 3 

PNF: 3 

Moist, north-facing 

slopes Fire Low 

Oak Creek Triteleia 

(Triteleia lemmoniae) O 

Coconino County: 23 

Yavapai County: 5 

PNF: 0 

Grasslands; 

Ponderosa pine forests 

Not known to occur 

on PNF Low 
80

Prescott NF coarse-filter plan components developed to reduce plant viability concerns: DCEcosystem Resilience - 1 

 Ecosystems retain all of their essential components, processes, and functions under changing and unc

environmental conditions. These resilient ecosystems provide a wide range of ecosystem services for 

needs. 

 Prescott NF landscapes retain capacity to survive natural disturbances and threats to sustainability su

climate change and an increasing human population. 

 Ecosystem functions (e.g., nutrient cycling, water infiltration, and carbon sequestration) are sustained 

grasslands, and desert communities adapt to changing conditions. 

 Ecosystems are resilient or adaptive to changing natural disturbance regimes (e.g., drought, wind, fire

pathogens), allowing for shifting of plant communities, structure, and ages across the landscape. 

 Ecological conditions for habitat quality, distribution, and abundance contribute to self-sustaining po

and aquatic plants and animals. Conditions provide for the life history, distribution, and natural popul

species within the capability of the ecosystem. 

DC-Veg-1 

 Diverse vegetation structure, species composition, and densities, provide quality habitat for native an

plant and animal species throughout their life cycle and at multiple spatial scales. Landscapes provide ecosystem diversity at multiple scales, including habitats for those species associated with old growth 

 Native plant communities dominate the landscape, while nonnative invasive species are nonexistent o

quantities. Establishment of invasive plant species new to the Prescott NF is prevented. Existing inva

prioritized for eradication, containment, or control. 

DC-Veg-4  Ecological conditions provide suitable habitat for plants identified as Southwestern Region sensitive DC-Veg-5 

 Locally endemic plant communities are intact and functioning. 

 Unique plant community habitats (e.g., limestone cliffs, margins of seeps and springs, Verde Valley F

flows/cinders, calcareous soil/alkaline clay, canyons/cliffs and ledges, granitic soils/igneous rocks, sariparian forest) are present to maintain well distributed populations of associated native plant species

 Native plants provide nectar, floral diversity, and pollen throughout the seasons that pollinator specie

habitat conditions promote pollinator success and survival. 

 Species identified as culturally important are valued and, therefore, enhanced and protected. 
81

Table 8. List of Vascular Plants on the Prescott NF having Some Risk to Viability. 

Name RFSS Status? Known Populations Habitat Association Viability Risk Factors Viability Risk Plan c

Arizona Wild Buckwheat 

(Eriogonum arizonicum) No 

Coconino County: 1 

Yavapai County: 10 

PNF: 5 

Cobbly ridges/ hills; 

Calcareous alluvial 

soils 

OHV use Some 

Coar

Desire

Desir

Fin

St

Guide-P

4, Gu

M

*Guid

Basin Bladderpod 

(Lesquerella cinerea) No

Coconino County:11 

Yavapai County: 38 

PNF: 10 

Cobbly ridges/ hills; 

Calcareous alluvial 

soils 

OHV use Some 

White Mountain Bladderpod 

(Lesquerella pinetorum) No

Coconino County: 6 

Yavapai County: 8 

PNF: 3 

Calcareous alluvial 

soils OHV use Some 

Mearns Lotus 

(Lotus mearnsii var. mearnsii) No

Coconino County: 13 

Yavapai County: 50 

PNF: 13 

Grasslands; 

Calcareous alluvial 

soils 

OHV use Some 

Broadleaf Lupine 

(Lupinus latifolius var. 

leucanthus) 

Yes 

Coconino County: 0 

Yavapai County: 21 

PNF: 19 

Perennial streams, 

seeps and springs 

Weed invasion, 

Wetland degradation* Some 

Macdougal's Bluebells 

(Mertensia macdougalii) No

Coconino County: 63 

Yavapai County: 5 

PNF: 3 

Grasslands; 

Ponderosa pine forests OHV use Some 

Skunk-top Scurfpea 

(Pediomelum mephiticum) No

Coconino County: 4 

Yavapai County: 12 

PNF: 8 

Grasslands; 

Verde Formation OHV use Some 

Arizona Phlox 

(Phlox amabilis) Yes 

Coconino County: 17 

Yavapai County: 27 

PNF: 9 

Cobbly ridges/hills OHV use Some 

Hualapai Milkwort 

(Polygala rusbyi) Yes 

Coconino County: 0 

Yavapai County: 78 

PNF: 20 

Grasslands; 

Verde Formation 

OHV use, weed 

invasion Some 

Mearns Sage 

(Salvia dorrii ssp. Mearnsii) Yes 

Coconino County: 0 

Yavapai County: 74 

PNF: 38 

Cobbly ridges/ hills; 

Verde Formation 

OHV use, weed 

invasion Some 

Black Dropseed 

(Sporobolus interruptus) No 

Coconino County: 55 

Yavapai County: 6 

PNF: 5 

Ponderosa pine forests OHV use Some 
82

Prescott NF fine-filter plan components developed to reduce plant viability concerns: Standard-Plants-1 Collection of Southwestern Region Sensitive Plants shall occur for research or scientific purposes onGuide-Plants-1 Design features and/or mitigation measures should be incorporated in all Forest Service projects, as n

Southwestern Region Sensitive Plant Species do not trend toward listing as threatened or endangered

Guide-Plants-2 

Applicable design features in appendix B—Design Features, Best Management Practices, Required P

Mitigation Measures—from the “Final Environmental Impact Statement for Integrated Treatment of 

Weeds” (Forest Service, 2005a) or more current direction—should be followed in treating nonnative and for managing site disturbing projects and maintenance. 

Guide-Plants-3 

Efforts to improve severely disturbed sites, especially those within the vicinity of occupied Southwes

Plant Species habitat, should be undertaken to reduce non-native invasive plant species colonization, 

improve watershed condition. 

Guide-Plants-5 In cases where plant collection permits are issued, collecting seeds or cuttings should be encouraged

physically removing whole plants should be discouraged. 

Guide-Range-4 Livestock salting should be located away from known locations of Southwestern Region Sensitive P

plants are not adversely affected by associated trampling. 

Standard-Rec-1 Only designated roads, motorized trails, and motorized use areas as depicted and described on the M

Map are open to public motorized vehicle use. 

Guide-Rec-5 Unauthorized travel routes should be returned to natural conditions to discourage continued use. Guide-Minerals Materials-5 

Occupied Southwestern Region sensitive species habitat should be avoided during development of n

extraction sites. Heavy equipment use and material removal should not take place in occupied Southwsensitive species habitat within current or new permitted sandstone or dolomitic limestone quarries. 
83

Fine-filter plan components developed to reduce viability concerns for plants found near streams, seepGuideFish/Aquatics-2 Design features, mitigation, and project timing considerations should be incorporated into ground-di

may affect Southwestern Region sensitive species’ occupied habitat near streams, seeps, and springsare not limited to: undisturbed areas, timing restrictions, adjusted intensity of use, and avoiding use o

Guide-Recreation-8 New developed campgrounds and designated dispersed campsites should be located away from ripar

and other environmentally sensitive areas. 

Prescott NFfine-filter plan components developed to reduce viability concerns for plants found within th

Guide-Plants-6 

Within the Verde Formation: 

 New developments for mineral materials and motorized trails should be located outside of ar

medium or high potential rare plant habitat. 

 Plant surveys for Southwestern Region sensitive species should be carried out before using a

the implementation of projects. 

Table 9. List of Vascular Plants on the Prescott NF having Some Risk of Viability due to restricted loc

Name RFSS Status? Known Populations Habitat Association Viability Risk Factors Viability Rating Plan c

Southwestern Ringstem 

(Anulocaulis leiosolenus var. 

leiosolenus) 

No 

Coconino County: 5 

Yavapai County: 5 

PNF: 2 

Verde Formation OHV use, mining, weed invasion Some Coar

Desire

Desir

Fin

Std

Guide-P

4, Gu

M

Yavapai Wild Buckwheat 

(Eriogonum ericifolium) Yes 

Coconino County: 0 

Yavapai County: 22 

PNF: 1 

Verde Formation OHV use, mining, weed invasion Some 

Ripley's Wild Buckwheat 

(Eriogonum ripleyi) Yes 

Coconino County: 0 

Yavapai County: 28 

PNF: 6 

Verde Formation OHV use, mining, weed invasion Some 

Verde breadroot 

(Pediomelum verdiensis) Yes 

Coconino County: 4 

Yavapai County: 12 

PNF: 8 

Verde Formation OHV use, mining, weed invasion Some 
84

Appendix A. 

 List of vascular plant taxa of conservation concern for the Prescott National Forest for which 

there is no immediate viability concern and for which there are no specific conservation 

recommendations except that they remain as target species when general rare plant surveys 

are conducted and selected populations, if applicable, are occasionally monitored. 

Abronia nana 

Species overview

Abronia nana is a small perennial herb with rather showy white flowers. 

Life history

 Considering its small stature, individuals of Abronia nana are probably short-lived. 

Flowers emerge between April and August. 

Distribution and abundance

 A wide spread species occurring from Arizona (Apache, Coconino, Mohave, and 

Yavapai, counties), California (Inyo and San Bernardino counties), Colorado, (Mesa and 

Montrose counties), Nevada (Clark, Elko, Esmeralda, Eureka, Lincoln, Nye, and White 

counties), New Mexico (San Juan and Sandoval counties), and Utah (Beaver, Duchesne, 

Emery, Garfield, Juab, Kane, Millard, Sevier, and Washington counties). 

Habitats

Populations of the taxon occur on rock ledges, among rocks, south and east-facing 

slopes, and sandy washes. Soil substrates include white gypsum, sand, red clay loam, and 

sandstone. Elevation ranges between 700m (2296ft) and 1432m (4698ft) with a mean elevation 

of 1066m (3497ft). Vegetation types include desert shrub, piñon-juniper woodland, and 

sagebrush- juniper woodland. 

Known and potential threats

 There appear to be no serious threats to the continued viability of this species. 

Recommended conservation strategies

 Because Widespread and fairly common, collected only once in PNF but at edge of range 

no conservation strategies are recommended at this time. 
85

Agastache rupestris 

Species overview

Agastache rupestris is a rather tall, fragile perennial with very fragrant foliage. In the 

HDMS, it is referred to as the Baboquivari Giant Hyssop. The species is in cultivation and is 

being sold by native plant nurseries. 

Life history

 Individuals are probably short-lived. Flowers emerge between July and October. 

Distribution and abundance

 A widespread species occurring from Sonora, Mexico to Arizona (Gila, Graham, Santa 

Cruz, and Yavapai counties), and New Mexico (Catron, Dona Ana, Grant counties). 

A population occurs along a narrow canyon south of the 89A pass at Mingus Mtn., 

possibly near Black Canyon Spring. The specimen may be in PNF herbarium (Erik Moore, pers. 

comm.). Better collection data may be available in a report by Eric Glomski and Erik Moore 

regarding the health of perennial streams in PNF. No copies of the report have been located 

and may all be in storage at Verde District Office. Eric Glomski, Eric Moore, and Ron Stein 

have been contacted but none have copies. A collection was made by L. N. Goodding (210-47) 

in the same area in 1947. 

Habitats

 Populations of the taxon tend to occur on exposed north and west-facing rocky slopes, 

near the tops and bottoms of cliffs and canyons, and among grantie boulders; with substrates 

including granite and limestone. Elevation ranges between 500m (1640ft) and 1300m (4200ft) 

with a mean elevation of 900m (3497ft). Vegetation types include pine forest, evergreen forest, 

piñon-juniper woodland, and chaparral. 

Known and potential threats

 No threats are known for the species. 

Recommended conservation strategies

1. Verification of locations within the Forest. Since current records of the species within the 

Forest are ambiguous, an attempt to relocate and better document these sites would aid in 

monitoring and conservation efforts. 

2. Maintain the species on target lists for future surveys of rare plant species. 
86

Allium bigelovii 

Species overview

Allium bigelovii is an herbaceous perennial that grows to 20cm tall. 

Life history

Although small in stature, it is unknown how many years that plants can sprout from their 

underground corms. Flowers March through May. 

Distribution and abundance

A widespread species occurring from Arizona (Coconino, Gila, Greenlee, Maricopa, 

Mohave, Navajo, and Yavapai counties), to New Mexico (Hidalgo, Grant, Luna, and Dona Ana 

counties). 

This species has been collected twice within the Forest by T. Wright (1043, 1441), once 

within grassland and another in scrubland. 

Habitats

Populations of the taxon tend to occur on east and north-facing slopes and on open rocky 

hilltops; with substrates including tertiary lake bed deposits, basalt, siltstone, sandstone, 

limestone, and gravel alluvium, with white and loamy soils. Elevation ranges between 558m 

(1500ft) and 1840m (1636ft) with a mean elevation of 1216m (3889ft). Vegetation types include 

Bouteloua gracilis-Aristida purpurea grassland, Sonoran desert scrub, semi-desert grassland, 

and juniper-canotia open grasslands. 

Known and potential threats

There appear to be no serious threats to the continued viability of this species. 

Recommended conservation strategies

 Because the species is widespread in Arizona and New Mexico and the habitat nonspecific no conservation strategies are recommended at this time. 

Apodanthera undulata 

Species overview

 Apodanthera undulata is a perennial vine extending 2-4m, with a disagreeable odor and 

generally a few yellow flowers. 
87

Life history

Although the herbage dies back during the winter, the plants probably are long-lived 

resprouting indefinitely from their tuberous roots. Flowers May-October. 

Distribution and abundance

A widespread species occurring from Aguascalientes (Calvillo), Sonora (Agua Prieta, 

Arivechi, Cucurpe, Granados, Magdalena, Naco, Nogales, Nacozari de Garcφa, Santa Cruz, 

and Yocora), Chihuahua, Coahuila, Durango, Guanajuato, and Oaxaca, Mexico, through 

Arizona (Cochise, Gila, Graham, Pima, Maricopa, Pinal, Santa Cruz, and Yavapai counties), 

New Mexico (Dona Ana, Hildago, Luna, Grant, and Otero counties), and Texas (El Paso 

county). 

Populations of the species have been collected from two areas within or near to PNF, 

one south of Wilhoit (Baker 14913), and the other collected by Deaver in 1975 west of 

Cottonwood. The species is not listed in the Arizona's Natural Heritage Program's Heritage Data 

Management System (HDMS). 

Habitats

Populations of the taxon tend to occur on gentile south and east-facing slopes, sandy 

flats, and highly disturbed areas; with substrates including decomposing granite, sand, silt and 

alluvial terrace. Elevation ranges between 550m (1840ft) and 2000m (6580ft) with a mean 

elevation of 1275m (4192ft). Vegetation types include grassland, Chihuahuan desert scrub, 

scattered oaks, and mesquite woodland.

Known and potential threats

There appear to be no serious threats to the continued viability of this species. 

Recommended conservation strategies

 Because the species is a Chihuahuan Desert species and only occurs in PNF at the edge 

of its range no conservation strategies are recommended at this time.
88

Asclepias uncialis 

Species overview

Asclepias uncialis is a small perennial herb with several to many spreading or erect 

stems (2-6 cm tall), with narrow to lance-shaped leaves occurring primarily opposite of each 

other and with clusters of 7 to 12 rose-purple flowers at the tips of the stems. 

Life history

Flowers from late March to late May; fruiting occurs from May to early July. The flowers 

are highly modified in structure and require insect visitor for pollination. Seeds mature at a 

relatively fast rate of approximately 40 days after pollination.

Distribution and abundance

Asclepias uncialis occurs over a large geographical area (Wyoming to New Mexico), but 

it is currently only known from about 25-30 localities. In Arizona, it is known from Coconino, 

Pima and Santa Cruz Counties. It exhibits a natural rarity and low population sizes. There are 

no documented surveys for the species in Yavapai County. It is not known to occur on the 

Prescott NF. The species may be easily overlooked by surveyors, due to its extremely small 

size, early bloom period, and the lack of widespread botanical focus. 

Habitats

Populations of the taxon are most often found in grassland vegetation types on bare, 

open patches of soil between clumps of grasses in areas dominated by Bouteloua gracilis (blue 

gramma) and adjacent open woodlands dominated by pinyon and juniper or madrean evergreen 

oaks. Elevation ranges between 1461m (4790ft) and 1525m (5000ft) based on collections in 

SEINet. 

Known and potential threats

The species occurs most often in plant communities that appear to be in a stable 

condition with little change in plant composition. The species does not appear to tolerate 

competition from weedy annual species. It is unknown what impact fire and livestock grazing 

has on the species. Overgrazing could alter the composition of native plant communities in an 

area, increasing competition from weedy species and possibly altering the spectrum of 

pollinators available (Locklear 1991). In some cases, this species has been found on soils 

disturbed by vehicles or other human activities. 
89

Recommended conservation strategies

Because the species occurs over a large geographical area (Wyoming to New Mexico), and is 

found in only three counties within Arizona, no conservation strategies are recommended until it 

is found to occur within Yavapai County.

Astragalus calycosus var. scaposus 

Species overview

Astragalus calycosus var. scaposus is a perennial herb with silvery leaves and purple 

and white flowers; extraordinarily large plants have been collected in PNF. 

Life history

Flowers from April –June, and some have been documented to be flowering in October. 

Distribution and abundance

A widespread species occurring from Arizona (Apache, Coconino, Gila, Mohave, 

Yavapai, and Navajo counties), Colorado (Montezuma and Monroe counties), Nevada (Lincoln 

and White Pine counties), New Mexico (Catron, San Juan, Cibola, La Plata, McKinley, 

Sandoval, and Socorro counties), and Utah (Iron, Juab, Kane, San Juan, and Washington 

counties). 

Although most collections for the taxon have been made within the Verde Valley, many 

have been recorded outside of the area in several habitats. The species is not listed in the 

Arizona's Natural Heritage Program's Heritage Data Management System (HDMS). Herbarium 

specimens should be re-examined to verify that they are identified properly. 

Habitats

Populations of the taxon tend to occur on all aspects of steep and shallow slopes and in 

canyons; with substrates including fine brown silt, quartzite, basalt, sandstone, gravel, and 

limestone. Elevation ranges between 699m (2293ft) and 2145m (4665ft) with a mean elevation 

of 1422m (4665ft). Vegetation types include bouteloua grassland, mixed shrub, pine and juniper 

communities, and desert shrub. 

Known and potential threats

There appear to be no serious threats to the continued viability of this species. 

Recommended conservation strategies

Because there have been many collections from Arizona, New Mexico, and Utah showing 
90

that the species is common over a large range no conservation strategies are recommended at 

this time.

Carex ultra 

Species overview

Carex ultra is a herbaceous perennial that can grow up to 2m tall, with spikelets that are 

long for a sedge, 5.0-10.2 cm (2.0-4.0 in.), generally occurring in shady areas and in moist soils. 

Life history

Individuals are robust and probably long-lived if conditions are favorable. Flowers March 

through September 

Distribution and abundance

A widespread species occurring from Mexico (Sonora and Coahila), to Arizona (Cochise, 

Coconino, Graham, Pima, Pinal, Santa Cruz, and Yavapai counties), and New Mexico (Grant, 

Hildalgo, and Sierra counties). 

Habitats

Populations of the taxon tend to occur is shaded areas on east and south-facing slopes, 

riparian areas, and the bottom of canyons; with substrates including granite, sand and gravel, 

and alluvial soils. Elevation ranges between 610m (2001ft) and 1800m (5905ft) with a mean 

elevation of 1205m (4002ft). Vegetation types include riparian woodland, oak- piñon woodland, 

and mixed conifer forest. 

Known and potential threats

There appear to be no serious threats to the continued viability of this species. 

Recommended conservation strategies

Because the species occurs at the southern edge of PNF but has not actually been found 

in the forest no conservation strategies are recommended at this time.

 
91

Cleome lutea var. jonesii 

Species overview

Cleome lutea var. jonesiii is a generally tall annual, growing up to 2m (6ft), with yellow 

flowers. 

Life history

 The species flowers May through September. 

Distribution and abundance

The species is endemic to Arizona (Cochise, Coconino, Mohave, Gila, Pima, Pinal, Santa 

Cruz, and Yavapai counties). 

Populations of this taxon occur within PNF in grasslands to the east and north of Chino 

Valley. The species is not listed in the Arizona's Natural Heritage Program's Heritage Data 

Management System (HDMS). 

Habitats

Populations of the taxon tend to occur in riparian areas, flood plains, dry gullies and 

disturbed areas such as road sides; with substrates including basalt, gravel, and sandy soils. 

Elevation ranges between 610m (2001ft) and 1640m (5546ft) with a mean elevation of 1128m 

(3723ft). Vegetation types include Populus-Salix woodland, grasslands, and oak woodland. 

Known and potential threats

There appear to be no serious threats to the continued viability of this species. 

Recommended conservation strategies

Because of the widespread distribution of the species in Arizona and a somewhat weedy 

nature no conservation strategies are recommended at this time.

Cupressus arizonicus (pygmy) 

Species overview

Unlike the pygmy cypress that occurs in California (Cupressus pigmaea), the pygmy 

Arizona cypress of PNF have not been formally named. The unique form of individuals within 

the pygmy forest of PNF are most certainly caused by the nature of their habitat such as shallow 
92

soils overlaying bedrock. 

Life history

 Although severely stunted, individuals within the pygmy forest are probably very old. Like 

typical individuals of Cupressus arizonicus, cones form between 

Distribution and abundance

The species is endemic to Arizona (Cochise, Coconino, Mohave, Gila, Pima, Pinal, Santa 

Cruz, and Yavapai counties). 

Habitats

Populations of the taxon tend to occur in riparian areas, flood plains, dry gullies and 

disturbed areas such as road sides; with substrates including basalt, gravel, and sandy soils. 

Elevation ranges between 610m (2001ft) and 1640m (5546ft) with a mean elevation of 1128m 

(3723ft). Vegetation types include Populus-Salix woodland, grasslands, and oak woodland. 

Known and potential threats

There appear to be no serious threats to the continued viability of this species. 

Recommended conservation strategies

Because of the occurrence of the species within habitat that is not threatened by human 

or natural disturbances no conservation strategies are recommended at this time.

Draba asprella var. stelligera 

Species overview

Draba asprella is a small perennial herb to 15cm tall with a rosette of simple entire 

leaves; D. asprella var. stelligera is distinguished by its fruits covered in short, dense hairs. 

Another variety, D. asprella var. kaibabensis is not recognized by FNA (Flora of North America 

Editorial Committee. 2010) 

Life history

 Often protected by limestone and sandstone outcrops. Flowers between April and July. 

Distribution and abundance
93

 Populations of the taxon are endemic to Coconino and Gila County, with 34 occurrences 

listed in Seinet and two localities listed from additional sources. In Coconino County, there are 

29 occurrences in the central and southern portions, ranging 210km; and in northern Gila 

County, there is a single occurrence. There are six records in Seinet without locality data. For 

the species, there are six locations spread over PNF with a range of 88km with two locations 

within 1km of each other. Note that there are an additional 21 records in Seinet for Draba 

asprella var. kaibabensis and a total of 148 records for the species, most of which have not 

been identified to species. 

Habitats

 Populations of the taxon tend to occur on northeast and southwest-facing slopes; with 

substrates including sandy loam and alluvial soil. Elevation ranges between 1311m (2132ft) and 

2134m (5741ft) with a mean elevation of 1200m (3936ft). Vegetation types include Pine forest, 

Evergreen forest, piñon-juniper woodland, and Chaparral. 

Known and potential threats

 Fire is a potential threat for the species but there is no information on fire tolerance for 

the species. 

Recommended conservation strategies

1. A review of herbarium material is necessary to determine whether the taxon (Draba asprella

var. stelligera) occurs within the Forest. 

2. Maintain the species on target lists for future surveys of rare plant species. 

Recommended monitoring

 If a review of herbarium material and/or natural populations determines that the taxon 

does occur within the Forest, then monitoring of selected populations would be a useful step in 

determining whether threats exist and whether conservation strategies would facilitate the 

viability of the taxon. 

References

Flora of North America Editorial Committee. 2010. Flora of North America. 7:293-294. 
94

Echinocereus yavapaiensis 

Species overview

Echinocereus yavapaiensis is a cespitose shrub with thick succulent stems and showy 

red flowers. It differs from its closest relative, E. coccineus, in having more ribs, more uniform 

spines, and occurring in lower, dryer habitats. Also, E. coccineus has 44 chromosomes and E. 

yavapaiensis has 66, which is the highest number in the genus. 

Life history

 Individuals of Echinocereus yavapaiensis probably live decades and produce clusters of 

over a hundred stems. Individuals grow fairly quickly, however, and may not be as old as they 

appear. Plants can germinate from seeds and flower within three years. Flowers generally 

open in March. 

Distribution and abundance

Although known populations of the Echinocereus yavapaiensis are restricted to Yavapai 

County, Arizona, they are common within their range and individuals are generally abundant. 

The species is not listed in the Arizona's Natural Heritage Program's Heritage Data 

Management System (HDMS). 

Habitats

Populations of the taxon tend to occur on south-facing hills, in canyons, in boulder 

outcrops and in dry washes; with substrates including granite, basalt, dark gray purple schist, 

red rhyolite, and quartzite. Elevation ranges between 650m (2132ft) and 1750m (5741ft) with a 

mean elevation of 1200m (3936ft). Vegetation types include Quercus emoryi scrub, Pinus edulis

woodland, desert scrub, and transition scrub. 

Known and potential threats

There appear to be no serious threats to the continued viability of this species. 

Recommended conservation strategies

Because the occurrence of the species is primarily in protected habitats where it is 

common and abundant within its limited range no conservation strategies are recommended at 

this time. 
95

Ephedra fasciculata 

Species overview

Ephedra fasciculata is a perennial 

Life history

Gymnosperm 

Distribution and abundance

A widespread species occurring from Mexico (Baja Cal Norte), through Arizona (Apache, 

Coconino, Gila, Graham, Greenlee, La Paz, Maricopa, Mohave, Navajo, Pinal, Yavapai, and 

Yuma counties), California (Imperial, Inyo, and San Bernardino counties), Nevada (Clark 

county), and Utah (Washington County. 

Habitats

Populations of the taxon tend to occur north, east, and west-facing steep slopes, along 

benches and saddles, in sandy washes, amount large rocks, and along roadsides; with course 

soil substrates including igneous gravel, granite, and sandy soils. Elevation ranges between 

335m (1099ft) and 1300m (4265ft) with a mean elevation of 817m (2682ft). Vegetation types 

include upland Sonoran desert, juniper grassland, piñon-juniper-scrub oak. 

The species is not listed in the Arizona's Natural Heritage Program's Heritage Data 

Management System (HDMS). 

Known and potential threats

There appear to be no serious threats to the continued viability of this species. 

Recommended conservation strategies

Because the species is wide spread and common no conservation strategies are 

recommended at this time. 

Erigeron anchana 

Species overview

Life history

Flowers May through August 
96

Distribution and abundance

The species is endemic to Arizona (Gila, Maricopa, Pinal and Yavapai counties). 

Habitats

Populations of the taxon tend to occur north, east, and south-facing cliffs, rock crevices, 

ledges, and rock faces; with substrates including weathered granite, limestone, rhyolite, and 

quartzite. Elevation ranges between 1068m (3503ft) and 2135m (7009ft) with a mean elevation 

of 1601m (5252ft). Vegetation types include chaparral to pine forests. 

 A single collection within the general PNF area for the species was made (Baker 14203) 

in the Granite Dells. Populations generally occur on rock faces near perennial streams. 

Known and potential threats

There appear to be no serious threats to the continued viability of this species. 

Recommended conservation strategies

 Because the species has not been found in PNF no conservation strategies are 

recommended at this time. 

Erigeron saxatilis 

Species overview

Life history

Flowers April through October 

Distribution and abundance

The species is endemic to Arizona (Coconino, Gila, and Yavapai counties). 

Habitats

Populations of the taxon tend to occur on various aspects of slopes, canyons, shaded 

cliffs, and rock outcrops; with substrates including limestone and sandstone. Elevation ranges 

between 1355m (4445ft) and 2545m (6397ft) with a mean elevation of 1950m (6397ft). 

Vegetation types include deciduous forests and chaparral. 

Known and potential threats

There appear to be no serious threats to the continued viability of this species. 
97

Recommended conservation strategies

Because the species occurs primarily in protected habitats no conservation strategies are 

recommended at this time. 

Eriogonum corymbosum var. glutinosum 

Species overview

Eriogonum corymbosum var. glutinosum is a perennial. 

Life history

Arizona specimens are not quite typical. 

Distribution and abundance

A widespread species occurring from Arizona (Apache, Coconino, Cochise, Mohave, 

Yavapai, and Navajo counties), through Nevada (Clark county), and Utah (Emery, Iron, Kane, 

Utah, Washington, and Wayne counties). 

The species is listed in the Arizona's Natural Heritage Program's Heritage Data 

Management System (HDMS) as a G5 S3. No records of occurrences within PNF or 

surrounding areas for the species were found. 

Habitats

Populations of the taxon tend to occur on shallow north-facing slopes; with substrates 

including cinders, sandstone, clay, shale, and gypsum. Elevation ranges between 650m (2132ft) 

and 2470m (8103ft) with a mean elevation of 1560m (5117ft). Vegetation types include 

deciduous ponderosa pine forest, short-grass grassland, atriplex desert, desert shrub. 

Known and potential threats

There appear to be no serious threats to the continued viability of this species. 

Recommended conservation strategies

Because the species has not been found in PNF no conservation strategies are 

recommended at this time. 
98

Eriogonum ericifolium var. pulchrum 

Species overview

Eriogonum ericifolium var. pulchrum is a small subshrub with pubescent leaves. It 

generally has a somewhat bonsai form and is rather attractive with its clusters of white flowers. 

Life history

 Although small, individuals have the appearance of age. Flowers emerge between 

August and November. 

Distribution and abundance

The species is endemic to Arizona (Apache, Coconino, Mohave, and Navajo counties). 

Habitats

Populations of the taxon tend to occur on north, west, and south-facing slopes, small 

washes, and on the edge of mesas; with substrates including limestone, sandstone, chert, 

gravel and basalt. Elevation ranges between 1372m (4051ft) and 1770m (5807ft) with a mean 

elevation of 1571m (4929ft). Vegetation types include high desert and piñon-juniper woodland. 

 Populations for this taxon are restricted to the Verde Formation at the eastern edge of the 

Forest in the Verde Valley. 

Known and potential threats

There appear to be no serious threats to the continued viability of this species. 

Recommended conservation strategies

Because the species has not been found in PNF no conservation strategies are 

recommended at this time. 

Eriogonum heermannii var. floccosum 

Species overview

Eriogonum heermannii var. floccosum is a small to medium sized subshrub with rather 

brittle stems an large clusters of white flowers. 

Life history
99

At least some individuals of Eriogonum heermannii var. floccosum appear to be very old. 

Flowers May through October 

Distribution and abundance

A widespread species occurring from Arizona (Mohave and Yavapai counties), California 

(San Bernardino county), and Nevada (Clark county). 

Habitats

Populations of the taxon tend to occur on south-facing slopes, shaded cliffs and rock 

outcrops; with substrates including limestone, and granite. Elevation ranges between 925m 

(3034ft) and 2116m (6942ft) with a mean elevation of 1520m (4986ft). Vegetation types include 

Juniperus osteosperma woodland, Yucca brevifolia woodland, Larrea tridentata- Ambrosia 

dumosa scrub, and chaparral. 

 A single collection within PNF for the taxon was made (Baker 9929) in the Juniper Mesa 

Wilderness Area. Populations generally occur on rock faces or rocky slopes.

Known and potential threats

There appear to be no serious threats to the continued viability of this species. 

Recommended conservation strategies

Because the species occurs on protected habitat, or at least where there are probably no 

conservation options, no conservation strategies are recommended at this time. 

Fremontodendron californicum 

Species overview

Fremontodendron californicum is woody shrub with large orange flowers. It is frequently 

planted in California for its ornamental properties, 

Life history

These often large shrubs are probably long-lived and may represent relic populations. 

The flowers appear April through October. 

Distribution and abundance

A widespread species occurring from Mexico (Baja California Norte and Baja California 

Sur), through Arizona (Coconino, Gila, Maricopa, Pinal, and Yavapai counties), and California 
100

(Fresno, Imperial, Kern, Lake, Las Angeles, Riverside, San Bernardino, San Diego, San Luis 

Obispo, Santa Barbara, Tulare, and Ventura). 

 A single collection within PNF for the taxon was made (Baker 15070) in the southern 

Bradshaw Mountains, just west of the summit of Twin Peaks. This is a widespread species with 

numerous isolated populations. 

Habitats

Populations of the taxon tend to occur on west and north-facing slopes; with substrates 

including basalt, quartzite talus, and granite, and schist and sandy soils. Elevation ranges 

between 700m (2296ft) and 2050m (6725ft) with a mean elevation of 1375m (4510ft). 

Vegetation types include chaparral, piñon -juniper woodland, ponderosa pine woodland, and 

oak woodlands. 

Known and potential threats

There appear to be no serious threats to the continued viability of this species. 

Recommended conservation strategies

Because the species has a wide range, although rare within PNF, no conservation 

strategies are recommended at this time. 

Lepidium montanum var. glabrum 

Species overview

Lepidium montanum var. glabrum is a perennial with stems slightly woody at base and 

small flowers. 

Life history

Flowers between April and October 

Distribution and abundance

A widespread species occurring from Arizona (Coconino, Apache, Mohave, Navajo, and 

Yavapai counties), Utah (San Juan and Wayne counties), and New Mexico (Dona Ana county). 

 The taxon has not yet been verified as occurring within PNF, although collections have 

been made very close to the eastern boundary in the Verde Valley. The species is not listed in 

the Arizona's Natural Heritage Program's Heritage Data Management System (HDMS). 
101

Habitats

Populations of the taxon tend to occur on northeast and southeast-facing slopes; with 

substrates including white limestone, red sand and deep sandy soils. Elevation ranges between 

914m (2998ft) and 2179m (7148ft) with a mean elevation of 1546m (5073ft). Vegetation types 

include desert shrub, piñon-juniper woodland, grasslands, and cottonwood riparian areas. 

Known and potential threats

There appear to be no serious threats to the continued viability of this species. 

Recommended conservation strategies

Because the species has not been found in PNF no conservation strategies are 

recommended at this time. 

Leptodactylon caespitosum (var. or sp. Nov.) 

Species overview

Leptodactylon caespitosum is a matted perennial obligate to dolomite cliff faces. Out 

populations differs from the typical form farther north by having five corolla lobes instead of four. 

Life history

Probably long-lived. Flowers May through August 

Distribution and abundance

A widespread species occurring from Arizona (Yavapai county) Colorado (Moffat county), 

Nevada (Elk, Eureka, Lander, Nye, and White Pine counties), and Utah (Dagget, Emery, 

Garfield, Juab, Millard, and Weber countes). 

Habitats

The taxon is a cliff obligate and populations are found on north and south-facing cliffs; 

with substrates including dolomite, limestone, gravel, and sand. Elevation ranges between 

1600m (4645ft) and 2560m (8398ft) with a mean elevation of 2080m (6521ft). Vegetation types 

include Juniperus coahuilensis and Pinus edulis woodland. 

 Populations of Leptodactylon caespitosum within PNF may represent a new taxon. 

Individuals appear to be cliff-obligates and are presently known only from dolomite cliffs north 

and northwest of Paulden. Surveys for the taxon have been conducted within all of the known 
102

potential habit within PNF (Baker 2001). 

Known and potential threats

There appear to be no serious threats to the continued viability of this species. 

Recommended conservation strategies

Because the species occurs primarily in protected habitats no conservation strategies are 

recommended at this time. 

Lesquerella arizonica 

Species overview

Lesquerella arizonica is a low perennial with showy yellow flowers. 

Life history

Probably short lived. The flowers occur April through June 

Distribution and abundance

A widespread species occurring from (Apache, Coconino, Maricopa, Mohave, Navajo, 

Santa Cruz, and Yavapai counties), to Utah (Kane and Washington counties). 

The taxon has not yet been verified as occurring within PNF, however, collections have 

been made very close to the northern boundary, south of Ashfork. Specimens originally 

identified within PNF as Lesquerella arizonica have been corrected to L. cinerea by Andrew 

Salywon. The species is not listed in the Arizona's Natural Heritage Program's Heritage Data 

Management System (HDMS). The species needs to be examined more closely taxonomically 

or, at the very least, its diagnostic characters need to be clearly defined and photographed. 

Habitats

Individuals of the species occur on north-facing slopes, along ridgelines and benches, in 

dry stream beads; with substrates including sandstone, limestone, gravel, and fosslilferous 

chert. Elevation ranges between 500m (4645ft) and 2135m (7004ft) with a mean elevation of 

1317m (4322ft). Vegetation types include piñon -juniper woodlands, and ponderosa forest. 

Known and potential threats

There appear to be no serious threats to the continued viability of this species. 
103

Recommended conservation strategies

Because the species has not been found in PNF no conservation strategies are 

recommended at this time. 

Margaranthus solanaceus 

Species overview

Margaranthus solanaceus is a small annual herbaceous plant with leafy stems and small 

white flowers. 

Life history

 Flowers August through September. 

Distribution and abundance

A widespread species occurring from Mexico (Sonora, Agua Prieta, and Santa Cruz 

Municipio), through Arizona (Cochise, Gila, Pima, Santa Cruz, and Yavapai counties), New 

Mexico (Eddy, Hildago, Otero, and Luna counties), and Texas (Hudspeth). A single collection 

within PNF for the taxon was made (Baker 14980) in the Bradshaw Mountains, at the Cements. 

Another collection was made near the Forest in Watson Woods Riparian Preserve (Baker 

12740). This is a widespread species with numerous isolated populations. 

Habitats

Individuals of the species occur on south-facing slopes, along sandy river banks, washes 

and in flood plains; with substrates including sand, rhyolite, limestone basalt, igneous rock, and 

granite cob. Elevation ranges between 768m (2519ft) and 2286m (7500ft) with a mean elevation 

of 1527m (5009ft). Vegetation types include riparian scrub, desert scrub, oak-juniper woodland, 

and oak grasslands. 

Known and potential threats

There appear to be no serious threats to the continued viability of this species. 

Recommended conservation strategies

Because the species has a wide range and somewhat common in south-east Arizona, no 

conservation strategies are recommended at this time, even though it is rare within PNF. 
104

Nicotiana quadrivalvis var. bigelovii 

Species overview

Nicotiana quadrivalvis var. bigelovii in a annual herbaceous plant with long, white flowers. 

It was used extensively by native cultures as tobacco. 

Life history

Flowers in June 

Distribution and abundance

Although this is widespread species throughout much of the western states, there has 

been only a single collection for the species in Arizona: from the southern Bradshaw Mountains, 

just south of Minnehaha Flats, near Rush Springs, 5,100' (DJM 1852). The collection in 

Minnehaha Flats may have cultural significance. 

Habitats

The species is known to occur in flat areas with sandy soils, at an elevation of 250m 

(820ft), within ponderosa pine woodlands. 

Known and potential threats

There appear to be no serious threats to the continued viability of this species. 

Recommended conservation strategies

Because the species is widespread in California and Oregon, though rare in PNF, no 

conservation strategies are recommended at this time 

Penstemon nudiflorus 

Species overview

Penstemon nudiflorus is a perennial herb with showy lavender flowers. 

Life history

Flowers March through September 
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Distribution and abundance

A species that occurs from Arizona (Yavapai, Gila, Navajo, Apache, and Coconino 

counties, to New Mexico (Sandoval and Bernalillo counties). 

Habitats

Individuals of the species occur on north and south-facing slopes, and along dry streams; 

with substrates including basalt. Elevation ranges between 1531m (5022ft) and 2302m (7555ft) 

with a mean elevation of 1917m (6289ft). Vegetation types include grass-scrub oak mosaic, 

ponderosa pine forest, and Bouteloua gracilis grassland. 

Although only a few collections for this distinct species have been made within PNF, it 

was not listed as a target species for past surveys. It is quite possible, therefore, that the 

species is much more common within PNF than the collections would indicate. Although 

apparently endemic to the state, it is a fairly widespread species of central and northwestern 

Arizona. 

Known and potential threats

There appear to be no serious threats to the continued viability of this species. 

Recommended conservation strategies

Thought the species has a limited distribution, it is common within its range, especially 

within PNF so no conservation strategies are recommended at this time. 

Penstemon oliganthus 

Species overview

Penstemon oliganthus is a low growing annual with stems arising from rosettes with not 

very showy purple flowers. 

Life history

The species flowers March through September 

Distribution and abundance

A widespread species occurring from Arizona (Apache, Coconino, Greenlee, Mohave, 

Navajo, and Yavapai counties), New Mexico (Cibola, Colefax, Grant, McKinley, Santa Fe, 

Sandoval, Socorro, Taos, Torrance, and Valencia counties). 
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Habitats

Individuals of the species occur on north-facing slopes, in open grassy areas and along 

among low growing shrubs; with sandy and volcanic soils, and substrates including gravel loam. 

Elevation ranges between 1500m (4921ft) and 3400m (11,154ft) with a mean elevation of 

2450m (8038ft). Vegetation types include mixed conifer forest and grasslands. 

 This distinct species is fairly widespread in northeastern Arizona and New Mexico. It 

appears that the single collection (McLellan 2027) within PNF may be close to the southwestern 

edge of its range. The species is not listed in the Arizona's Natural Heritage Program's Heritage 

Data Management System (HDMS). 

Known and potential threats

There appear to be no serious threats to the continued viability of this species. 

Recommended conservation strategies

Because the species is fairly widespread, though only one locality within PNF, no 

conservation strategies are recommended at this time. 

Perityle congesta 

Species overview

Perityle congesta is densely clumped subshrub to 30cm tall that generally occurs on cliff 

faces. It differs from other Perityle species in the area in having non-ciliate achenes. 

Life history

Although individuals of Perityle congesta are small, they appear to be long-lived. Flowers 

May through Septembers 

Distribution and abundance

A species that has a range from Arizona (Coconino county) to Utah (Washington county). 

Habitats

Populations of the taxon tend to occur on north and west-facing slopes, and in crevices 

along dripping cliffs; with substrates including sandstone and sculptured bedrock. Elevation 

ranges between 498m (1633ft) and 2316m (7598ft) with a mean elevation of 1407m (4612ft). 

Vegetation types include riparian woodland, desert scrub, and piñon -juniper woodland. 

 At present, there is no record of the species occurring in PNF. There is a record close to 
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the PNF boundary in the Sycamore Canyon Wilderness Area (Wright 92). The species is not 

listed in the Arizona's Natural Heritage Program's Heritage Data Management System (HDMS). 

Known and potential threats

There appear to be no serious threats to the continued viability of this species. 

Recommended conservation strategies

 Because the species has not been found in PNF no conservation strategies are 

recommended at this time. 

Phacelia rupestris 

Species overview

Phacelia rupestris is a bushy but herbaceous perennial or even suffrutescent shrub with 

brittle stems and delicate leaves. It is a somewhat showy species with often large clusters of 

white flowers. It is the only cliff-face perennial Phacelia in our area with white flowers. 

Life history

Although the herbage dies back during the winter, individuals of Phacelia rupestris can be longlived with rather thick trunks. Flowers April through September. 

Distribution and abundance

A widespread species occurring from Mexico (Nuevo Leon) through Arizona (Coconino, 

Gila, Greenlee, La Paz, and Yavapai counties), to New Mexico (Bernallilo, Dona ana, Eddy, 

Grant, Hildago, Luna, Otero, Sierra, and Soccoro counties). 

 The species is not listed in the Arizona's Natural Heritage Program's Heritage Data 

Management System (HDMS). 

Habitats

Populations of the taxon tend to occur on steep north, west and south-facing slopes near 

the top, and in narrow canyons; with substrates including limestone, sandstone, gravel, loam, 

igneous rock, and basalt. Elevation ranges between 304m (997ft) and 2439m (8001ft) with a 

mean elevation of 1236m (4499ft). Vegetation types include juniper- pine woodland. 

Known and potential threats
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There appear to be no serious threats to the continued viability of this species. 

Recommended conservation strategies

Because the species is widespread in New Mexico, Texas, and Mexico, thought rare in 

Arizona, no conservation strategies are recommended at this time. 

Puccinellia parishii 

Species overview

Puccinellia parishii is a dwarf annual 

Life history

Flowers April through July 

Distribution and abundance

A widespread species occurring from Arizona (Yavapai, and Coconino county), to New 

Mexico (Apache, Catron, Cibola, Grant, Hidalgo, McKinley, Sandoval, and San Juan counties), 

and California (San Bernardino county). 

 No records of Puccinellia parishii occur within PNF but there are is at least one record 

from Yavapai County near Bagdad. 

Habitats

Populations of the taxon tend to occur on open flat areas; with soil substrates including 

sandy clay loam and muddy flats. Elevation ranges between 792m (2600ft) and 2240m (7349ft) 

with a mean elevation of 1516m (4974ft). Vegetation types include riparian communities. 

Known and potential threats

There appear to be no serious threats to the continued viability of this species. 

Recommended conservation strategies

Because the species has not been found in PNF no conservation strategies are recommended 

at this time. 
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Stachys rothrockii 

Species overview

Stachys rothrockii is a perennial herb that grows in colonies from deep rootstocks with 

generally wilted corollas that are purple. 

Life history

Flowers June through October 

Distribution and abundance

A widespread species occurring from Arizona (Apache, Coconino, La Paz, Navajo, and 

Yavapai counties) and New Mexico (Catron, Cibola, Colfax, McKinley, Mora, Otero, San Juan, 

and Valencia counties). 

 Although there are no records for PNF, there is one record for Prescott. Stachys 

rothrockii is not listed in the Arizona's Natural Heritage Program's Heritage Data Management 

System (HDMS). 

Habitats

Populations of the taxon tend to occur on rocky north, west and east-facing slopes, and 

hill tops; with substrates including basalt, gravel, clay loam, and sand. Elevation ranges between 

1600m (5249ft) and 2256m (7401ft) with a mean elevation of 1928m (6325ft). Vegetation types 

include piñon - juniper community. 

Known and potential threats

There appear to be no serious threats to the continued viability of this species. 

Recommended conservation strategies

Because the species has not been found in PNF no conservation strategies are 

recommended at this time. 

Talinum validulum 

Species overview

Talinum validulum is a small perennial herb with narrow succulent leaves and pink 
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flowers that open in the late afternoon. It differs from a similar species that also occurs in the 

Forest by having fewer stamens. 

Life history

In cultivation, individuals are short-lived but are easily grown from seeds. Flowers June 

through September 

Distribution and abundance

The species is endemic to Arizona (Coconino and Yavapai couties). 

Habitats

Populations of the taxon tend to occur on northeast and southeast-facing slopes; with 

substrates including limestone, fosslilferous chert, rock and gravel. Elevation ranges between 

475m (1558ft) and 2156m (7032ft) with a mean elevation of 1315m (4314ft). Vegetation types 

include pine/oak/Juniper woodlands and mixed conifer forests. 

Known and potential threats

There appear to be no serious threats to the continued viability of this species. 

Recommended conservation strategies

Because the species occurs primarily in habitats little effected by grazing, fire, and other 

potential threats no conservation strategies are recommended at this time. 

Thelypodiopsis ambigua var. ambigua 

Species overview

Thelypodiopsis ambigua var. ambigua is an erect biennial with purple flowers. 

Life history

Flowers in May 

Distribution and abundance

The species is endemic to Arizona (Coconino, Mohave, and Yavapai counties). 

 Although there are no records of the taxon in PNF, the species was collected at the 

Granite Dells, near Prescott. The taxon is not listed in the Arizona's Natural Heritage Program's 

Heritage Data Management System (HDMS). 
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Habitats

Populations of the taxon tend to occur on south and west-facing slopes; with substrates 

including basalt and gravel. Elevation ranges between 790m (2591ft) and 1770m (5807ft) with a 

mean elevation of 1280m (4199ft). Vegetation types include juniper-yucca woodland. 

Known and potential threats

There appear to be no serious threats to the continued viability of this species. 

Recommended conservation strategies

Because the species is not know to occur in PNF no conservation strategies are 

recommended at this time. 

Thelypteris puberula var. sonoernsis 

Species overview

Thelypteris puberula var. sonoernsis is a woodland fern with long-creeping, scaly 

rhizomes. 

Life history

Fertile from March to October 

Distribution and abundance

A widespread species occurring from Mexico (Sonora, Alamos, Chihuahua, Baja 

California Norte, Guaymas Municipio, Rio Mayo Reigon, Shuaripa, San Javier, Santa Ana, and 

Yécora), through Arizona (Coconiono, Gila, Mohave, Pima, Pinal, and Yavapai counties), and 

California (San Bernardino, Los Angeles, and Santa Barbara counties). 

 Known populations of Thelypteris puberula var. sonorensis closest to PNF are near the 

Santa Maria River, Arizona. According to Flora of North America, Thelypteris puberula var. 

puberula does not occur in the U. S. 

Habitats

Populations of the taxon tend to occur on east and north-facing slope, in canyons, 

especially along streams and seepage areas; with substrates including calcareous tufa. 

Elevation ranges between 100m (328ft) and 2100m (6889ft) with a mean elevation of 1100m 

(3608ft). Vegetation types include oak woodland, riparian forest, Mohave Desert springs, and 
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tropical deciduous forests. 

Known and potential threats

There appear to be no serious threats to the continued viability of this species. 

Recommended conservation strategies

Because the species is not known to occur in PNF, no conservation strategies are 

recommended at this time.