# Fi eld Re lease o f the

Arundo Scale, Rhizaspidiotus donacis (Hemiptera: Diaspididae), an Insect
for B iological Control of

Arundo donax (Poaceae)
in the Continental
United States

Environmental Assessment,

December 20 10 United States Department of Agriculture

Marketing and Regulatory Programs

Animal and

Plant Health Inspection
Ser vice

# Field Release of the Arund o

Scale, Rhizaspidiotus donacis (Hemiptera: Diaspididae), an Insect for Biological Control of

Arundo donax (Poaceae) in the
Continental United States

Environmental Assessment,

December 20 10

Agency Contact: Shirley Wager

- Page, Branch Chief

Pest Perm itting
Plant Protection and Quarantine Animal and Plant Health Inspection Service U.S. Department of Agriculture 4700 River Road, Unit 133 Riverdale, MD 20737

– 1236

________________________________ __________________________ The U.S. Department of Agriculture (USDA) prohibits discrimination in all its

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– 2600 (voice and TDD).

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Room 3 26

– W, Whitten Building, 1400 Independence Avenue, SW, Washington,
DC 20250

– 9410 or call (202) 720

– 5964 (voice and TDD). USDA is an equal opportunity provider and employer.

________________________________ __________________________ Mention of companies or commercial products in this report does not imply

recomm endation or endorsement by USDA over others not mentioned. USDA neither guarantees nor warrants the standard of any product mentioned. Product names are mentioned solely to report factually on available data and to provide specific information.

________________________________ __________________________ This pu blication reports research involving pesticides. All uses of pesticides must be registered by appropriate State and/or Federal agencies before they

can be recommended.

________________________________ __________________________ CAUTION: Pesticides can be injurious to humans, domestic animals, desirable plant s, and fish or other wildlife

— if they are not handled or applied properly. Use all pesticides selectively and carefully. Follow recommended practices for the disposal of surplus pesticides and pesticide containers.

## Table of Contents

I. Purpose an d Need for the Proposed Action

......................... 1

II. Alternatives

................................ ................................ .............. 2

III. Affected Environment

................................ ............................. 5

IV. Environmental Consequences

................................ ............ 11

V. Other Issues

................................ ................................ .......... 2 5

VI. Agencie s, Organizations, and Person s Consulted

............ 26

VII. References

................................ ................................ ............ 27

Appendix A. Host Plant Test Li st for R. donacis

Appendix B. Results of No

- Choice Host Range Tests for

Rhizaspidiotus donacis

Appendix C. Results of No

- Choice Host Range Tests for

Rhizaspidiotus donacis in which 1,000 Crawlers

Were Released Per Plant1 

## I. Purpose and Need for the Pr oposed
Action

The U.S. Department of Agriculture (USDA), Animal and Plant Health Inspection Service (APHIS), Plant Protection and Quarantine (PPQ), Pest Permitting Branch (PPB) is proposing to issue permits for release of an

armored scale insect

, Rhizasp idiotus donacis (Leonardi) (H e m i ptera: Diaspididae)

. The agent would be used by the applicant for the biological

control of Arundo donax L. (giant reed, carrizo cane) in the continental United States. Before permits are issued for release of Rhizaspidiot us donacis ( R. donacis ) , the APHIS

– PPQ PPB must analyze the potential impacts of the release of this ag ent into the continental United States.

This en vironmental assessment 1 (EA) has been prepared, consistent

with USDA

– APHIS' National Environmental Polic y Act (NEPA) implementing procedures (Title 7 of the Code of Federal Regulations (CFR) part 372). It examines the potential effects on the quality of the human environment that may be associated with the release of R. donacis

to control infestations of Ar undo donax ( A. donax ) within the continental United States. This EA considers the potential effects of the proposed action and its alternatives, including no action.

The applicant’s purpose for releasing R. donacis is to reduce the severity

of infestatio ns of A. donax in the United States . It is an extremely invasive weed of riparian habitats and irrigation canals of the Rio Grande River

Basin and the S outhwestern U nited States. A. donax is native to the Old World from the Iberian Peninsula of Europe to south Asia, including

North Africa and the Arabian Peninsula. It has been cultivated in the Old World for thousands of years and has been widely introduced around the

world as an ornamental and for its fiber uses. It was introduced into North

America in the early 1500s by the Spanish for its fiber uses and quickly became naturalized. It is now found throughout the southern half of the

United Sta tes from Maryland to California; however, it is most invasive along muddy ban ks of creeks and rivers in the S o uthwestern United States

.

A. donax infestations in riparian habitats lead to loss of biodiversity

, stream bank erosion

, altered channel morphology

, damage to bridges

, increased costs for chemical and mechanical control along transportation corridors, and imped iment of law enforcement activities on the

international border. Additionally, this invasive weed competes for water resources in an arid region where these resources are critical to the environment, agriculture

, and municipal users. A. donax is a s evere threat

1 Regulations implementing the National Environmental Policy Act of 1969 (43 United States Code 4321 et seq.) provide that an environmental assessment ―shall include brief discussions of the need for the proposal, of alternatives as required by section 102(2)(E), of the environmental impacts of the proposed action and alternatives, and a listing of agencies and persons consulted‖ 40 CFR § 1508.9.2 to riparian areas where it displaces native plants and animals by forming massive stands that pose a wildfire threat (Frandsen and Jackson

, 1994). It may reduce stream navigability (Dudley

, 2000). It consumes excessive

amounts of water and c ompetes for water resources in an arid region prone

to pe rennial droughts . Under optimum conditions

, it can attain growth

rates of 0.7 m eters (m) per week or 10 centimeters ( cm ) per day, putting it among the fastest growing plants (Perdue , 1958; Bell

, 199 7). Under ideal growth conditions

, A. donax can produce more than 20 metric tons of

above

- ground dry mass per hectare (Perdue

, 1958).

Existing A. donax management options are expensive, temporary, and have nontarget impacts. In addition, release of R. donacis is expected to augment the impact of another biological control organism previously released against A. donax . For these reasons, the applicant has a need to

release R. donacis into the environment, an effective, host

- specific,

biol ogical control organism for the control of A. donax

.



## II. A lternatives

This section will explain the two alternatives available to the APHIS

– PPQ

– PPB

— no action (no issuance of permits) and issuance of permits for

environmental release of R. donacis . Al though APHIS’ alternatives are limited to a decision on whether to issue permits for release of R. donacis

, other methods available for control of A. donax are also described. These

control methods are not decisi ons to be made by the APHIS

– PPQ

– PPB

and the ir use is likely to continue whether or not permits are issued for

environmental release of R. donacis , depending on the efficacy of

R. donacis to control A. donax . These are methods presently being used to

control A. donax by public and private concerns.

A third alternative was considered but will not be analyzed further. Under this third alternative, the APHIS

– PPQ

– PPB would have issued permits for

the field release of R. donacis

, but the permits would contain special provisions or requirements concer ning release procedures or mitigating measures. No issues have been raised that would indicate that special provisions or requirements are necessary.



### A. No Action

Under the no action alternative, the APHIS

– PPQ

– PPB would not issue permits for the field release of R. donacis for the control of A. donax . The release of this biological control agent would not take place. The following methods are presently being used to control A. donax

. T hese

me thods will continue under the ―n o a ction‖ alternative

, and will likely continue even if permits are issued for release of R. donacis

.3 A. donax may be controlled using herbicides. Glyphosate is a broad

spectrum herbicide that is commonly used on a variety of wetland and aquatic plants

, such as water hyacinth ( Eic hhornia crassipes ) , giant

salvinia ( Salvinia molesta ) , saltcedar ( Tamarix spp .)

, a nd others, including

A. donax

. Glyphosate has prove n to be effective against A. donax (Finn and Minnesang

, 1990; USDA

– Forest Service

, 1993). One of the reasons

for its effe ctiveness is that glyphosate is a systemic herbicide and

, when used at appropriate times

, it is translocated to the roots, killing the entire plant. A number of techniques were developed for its use

, includ ing 1) use as a foliar spray, 2) cutting plant st ems and spraying

, or painting the herbicide on the surface of the cut, and 3) cutting stems, letting plants re

sprout, and treating the re

- sprouts with herbicide.

Additionally, an herbicide ( Habitat® ) with another active ingredient, imazapyr, has been de veloped and registered for use on A. donax

. In general, Habitat ® requires one to two applications and control may be achieved for several years. R emoval of dead canes may be necessary if stem densities are great enough to inhibit recovery of native veget ation

after treatment.

Mechanical methods of A. donax control include use of prescribed fire, heavy machinery (e.g. bulldo zer, Hydro

- axe), hand

- cutting, chipper, etc. ).

R emoval of dead canes may be necessary if there is a possibility that cut vegetation might create a flood hazard during high water events or if biomass density is great enough to inhibit recovery of native vegetation

. Burning is a cost

- effective way of removing biomass if it does not threaten native vegetation. Another, but more costly, means of removal is chipping. Equipment and labor are expensive rel ative to other forms of removal; however, the small dry chips that are produced pose little threat in terms of regeneration, and they do not form debris dams. Biomass removal by vehicle is expensive and

, generally

, not preferred due to its

lack of cost

- effectiveness. The use of heavy machinery

, such as the Hydro

- axe
, is extremely expensive and slow, cutting only about 3 to
4 acres per day (Bell

, 1997).

The Arundo wasp
, Tetramesa romana Walker ( Hymenoptera : Eurytomidae ) was approved for release in April 2009. It currently occurs in Texas and California. However, i t is not expected that Tetramesa

romana ( T. romana ) alone will completely control A. donax

. T he stem galling of A. donax ca used by T. romana results in stunte d stems and

sometimes death of the stems. When both T. romana and R. donacis are present, A. donax plants become severely stressed with extreme stunting and virtually no leaf production. 1. Chemical
Control

2. Mechanical
Control

3. Biological
Control4 

### B. Issue Permits for Environme ntal Release of

R. donacis

Under this alte rnative, the APHIS

– PPQ

– PPB would issue permits upon request and after evaluation of each application for the field release of the

armored scale insect R. donacis against A. donax . These permits would

contain no s pecial provisions or requirements concerning release procedures or mitigating measures.



### Biological Control Agent Information

a. Taxonomy

Order : H e m i ptera

Family : Diaspididae

Genus : Rhizaspidiotus

Species : donacis (Leonardi)

Common name : Arundo s cale

b. Geographical Range of R. donacis

R. donacis is limited to mild Mediterranean climates of Europe (Portugal, Spain, southeastern France, and southern Italy. It is not known whether

R. donacis will be able to establish throughout the range of A. d onax, but it is likely to be a subset of this range. It appears likely that R. donacis will

not establish north of USDA ’s Plant Hardiness Zone 8b (Goolsby, 2009)

. This corresponds to areas with minimum a verage temperatures of 10 to

20 °F, such as Gainesv ille, Florida, and Charleston, South Carolina.

c. Life History of R. donacis

The life cycle of R. donacis follows the generalized diaspidid (armored scale insect) life cycle described by Koteja (1990). The life cycle can be

summarized as follows: mobi le crawlers emerge from the body of the female, exit the protective scale cover or armor

, and disperse to new plant tissue. Crawlers settle on leaf collars, stem nodes, or rhizomes ( horizontal, usually underground stem that often sends out roots and

shoot s from its nodes ) to insert mouthparts and begin feeding. Crawlers

molt to the second instar

, called a white cap. Second instars are immobile,

and continue to grow in size and add concentric layers to their scale cover.

The late second instar female sca le is inseminated by the mobile, winged,

male scale. The female scale molts to the adult instar. The immobile5 adult female continues to feed and develop for several months before producing live crawlers.

The male scale has a different life cycle. Mal e crawlers molt to the second

instar. At the end of the second instar

, they emerge as winged adults at precisely the right time to mate with the late second instar , immobile

females.

Based on observations of native field collections of R. donacis , many crawlers settle on rhizomes, but only if the soil substrate is suitable (dry

and s andy/rocky substrates are most conducive to crawler survival) (Goolsby, 2009). Settled crawlers insert their mouthparts into the plant

and feed on plant cell fluids.

The timing of the molts from first to second nymphal instar and from

second instar to adult, and survival through these transitions varies among diaspidid species and within species seasonally (Kuwana, 1923; Carroll and Luck, 1984; Polavarapu et al., 2000) ; ho wever, the overall duration of immature development for R. donacis is consistent with studies on other species that are capable of producing more than one generation per year. Observations of populations collected in the native range suggest that

R. donac is completes two generations per year in the field, although the generations may differ in length (Malumphy, 1997). However, Goolsby (2009) observed only one generation per year for R. donacis in Italy. The length of time for one life cycle of R. donacis is 6 to 6.5 months (Goolsby, 2009)

.



## II I

. Affected Environment

A. donax is a b amboo

- like perennial that grows to 8 m tall, wi th thick,

well

- developed rhizomes . Plants are typically terrestrial but tolerate periodic flooding. In California

, from the late 1700s to early 1800s,

A. donax was often planted for erosion control in flood channels and as wind breaks. More recently, it has become problematic in riparian

corridors th roughout the S outhwestern United States and northern Mexico.

Dense , impenetr able stands typically develop, which often displace native vegetation, diminish wildlife habitat, and increase flooding and siltation in

natural areas. A. donax is also adapted to a periodic fire regime. The canes are readily flammable throughout much of the year, and the presence of A. donax increases the susceptibility of riparian corridors to fire. Large stands of A. donax can significantly increase water loss from underground aquifers in semi

- arid regions due to a high evapotranspiration rate, which is estimated at roughly three times greater than that of the native riparian vegetation. A. donax is cultivated as an ornamental, for industrial cellulose, and to produce reeds for woodwind instruments. It is6 an alternate host for beet western yellows vi rus, sugarcane mosaic virus,

and maize dwarf mosaic virus.

A

. donax r eproduces vegetatively from rhizomes and stem fragments

. Fragments disperse with water, mud, and human activities. Under optimal conditions, plants grow and spread rapidly during the warm season. Intact

rhizomes buried under about 1 to 3 m of silt can develop new shoots. Under experimental conditions, rhizome fragments readily develop new shoots from a depth of 25 cm , whereas stem fragments mostly re

- sprout
from a depth less than 10 cm . Viable seed has not been observed in North America or in the native range (DiTomaso and Healy

, 2003).

A. Areas Affected by A. donax

A

. donax is native to Europe from the central Atlantic coast of Portugal, inland along the major rivers of the Ibe rian Peninsula, along the Mediterranean coast from Spain to Greece, including th e warmer pa rts of

the Adriatic Coast. In n orth Africa along the Mediterranean

, the populations are discontinuous from the Western Sahara, Morocco, and Algeria , to the Arabian P eninsula. Remote populations are known from the Sahara in stable oases. Populations in China are not considered to be

native. In addition to A. donax , other Arundo species are native to the

Mediterranean

, including A

. plinii Turra, A

. collina Tenore

, a nd

A

. mediterranea (Danin et al., 2002; Danin, 2004; Danin et al., 2006). The only other known Arundo species outside of the Mediterranean is

A

. formosana in Taiwan.

A

. donax has a nearly worldwide distribution in tropical to warm

temperate regions. In the United States, it is invasive from northern

California across the S outhwestern and S outheastern United States to Maryland . It is widely distributed in Mexico, and Central and South

America. The m ost severe infestations in the United States are in Ari zona, California, and Texas, especially the Santa Ana River Basin and Rio

Grande Basin

.

A

. donax is well established in North America

, although it continues to spread into new areas. Figure 1 s hows the areas that are climatically

suitable based on CLIME X 2 parameters from Europe. While the predicted CLIMEX distribution broadly agrees with the actual distribution, A. donax has naturalized further north. It has been documented in South Bend,

Indiana

, and Coeur’d’alene, Idaho.

Some of the most severely in fested areas are in the Rio Grande Basi n and

in the coastal rivers of s outhern California. A continuous stand of

2 CLIMEX is ―software to predict the effects of climate on species. (See http://www.climatemodel.com/climex.htm .) 1. Native and

Introduced Range

2. Present and
Potential
Distribution
in North

America7 A. donax occurs from just south of Laredo to Del Rio, T exas . Th e swath

of A. donax is nearly 0.5 miles wide along this stretch of the Rio Gra nde

River . Furth er up river

, near Big Bend National Park, stands of A. donax are increasing in size and density. Heavy rains during the summer of 2007 stimulated new growth

, and flood waters distributed propagules downstream. Aerial surveys conducted by USDA researchers in the fall of

2007 revealed much more A. donax than had been previ ously seen in the 2002 surveys (Goolsby, 2008).

The spread of A. donax into new areas appears to be from earthmoving equipment and roadway mowers ( Goolsby, 2008 ). Once es tablished in a watershed, rhizomes and canes move downstream during flood events to

establish new stands. The movement of A. donax for biofuel trials also presents another means of spread. The State of Florida evaluated a request to plant A. donax on a p lantation south of Lake Okeechobee. Concerns presented by the Florida Exotic Pest Plant Council were that it could not be contained from entering the Everglades following high rainfall events

, such as major hurricanes (Florida Native Plant Society

, 200 6 ). This business venture is no longer planned for Florida, but instead is being considered for St. Augustine Co unty in east Texas (Loder

, 2007).

Fig ure 1. Areas in North America (red to pink) that are climatically suitable for

Arundo donax

.

A

. donax typically grows on sites with a low slope in riparian areas, floodplains, ditch es, and irrigation canals . In the E astern United States

, with average rainfall above 30 inches, it can grow in upland sites, such as windbreaks or in ornamental setting s. A

. donax occurs in a wide range of soils types with variable fertility, but grows best in well

- drained

, moist soils. Plants tolerate some salinity and extended periods of drought ; however

, they do not survive in areas with prolonged or regular periods of freezing temperatures (DiTomaso and Healy

, 2003). 3. Habitat8 

### B. Plants Related to A. donax and Their Distribution

Taxonomically Related Plants

Grass species (Poaceae) that were used in testing the specificity of

R. donacis to A. donax are listed below and i n a ppendix A

. Information regarding plants taxonomically related to A. donax is included in this

document because native plant species which are closely related to

A. donax have the most potential to be attacked by R. donacis

.

Andropogon glomeratus (Walt er) Britton et al. ( bu shy bluestem) is native

to the S outhern United States and north to Ne w York and south to

n orthern South America.

Aristida purpurea Nutt. var. longiseta (Steud.) Vasey (red threeawn) is

native from w estern Canada to n orthern Mexico an d grows in well

- drained

soils.

Arundinaria gigantea (Walter) Muhl. (giant cane) is native to the

S outheastern United States

.

Arundo formosana Hack. (fountain reed), a smaller relative of A . donax , is

native to Taiwan, the Ryukyu Islands of Japan, and the Philippines. It is a very minor ornamental plant in northern California.

Bouteloua hirsuta Lag. ( hairy grama) is a bunchgrass native to most of the

United States and south to Guatemala.

Chasmanthium latifolium ( Michx.) Yates (inland sea oats) is nativ e from

the Middle Atlantic States of the United States west to Texas and grows along waterways and in moist woods.

Cortaderia selloana (Schult. & Schult. f.) Asch. & Graebn. (pampas grass) is an ornamental grass native to Brazil and the southern part of

S outh America. Pampas grass has been planted in the southeast and

southwest of the United States

, and is invasive in some areas.

Cynodon dactylon (L.) Pers. (Bermuda grass) is a pasture and turf grass

native to Africa that now grows worldwide except in th e coldest and driest

areas.

Cyperus articulatus L. (

jointed flatsedge) is an obligate wetland plant

native to the area from South Carolina and Florida to Texas

, and south to

South America

, as well as Africa and Asia.9 Danthonia spicata (L.) P. Beauv. ex R oem. & Schult. (poverty oatgrass) is

native throughout most of North America from the s ubarctic through

central Mexico.

Dichanthelium acuminatum (Sw.) Gould and Clark ( tapered rosette grass)

is native to most of North America and south to Colombia and Ecu ador

, as well as in the Caribbean. It is endangered in Tennessee.

Digitaria cognata (Schult.) Pilg ( fall witchgrass) is native fro m Ontario, Canada, through the E astern half of the United States and into northern

Mexico.

Elymus virginicus L. ( Virginia wildrye) is native throughout most of

Canada and the United States.

Eragrostis intermedia Hitchc. ( plains lovegrass) is a native grass ranging

from the S outhern United States to Costa Rica.

Eragrostis spectablilis (Pursh) Steud. ( purple lovegrass) is n ati ve to southeastern Canada, the E astern two

- thirds of the United States

, and

south to Belize.

Eriocaulon decangulare L. ( tenangle pipewort) grows in moist to wet soils

from the mid

- Atlantic region of the United States through the Southeast

, and Mexico t o Nicaragua. It is endangered in Tennessee.

Leptochloa dubia (Kunth) Nees (green sprangletop) is a native to Florida

, O klahoma to Arizona

, and south through Mexico. It is best adapted to deep sandy soils in Florida

, and to rocky hills and canyons in the rest of its

range

.

Leptochloa fusca (L.) Kunth subsp. uninervia (J. Presl) N. Snow (= L.

uninervia ) (red sprangletop) is native to the southern half of the

United States and much of Mexico, the Caribbean, and Central and South America. This species is no w an invasive species in rice fields in Spain and Italy.

Leptochloa panicea (A. Retzius) J. Ohwi subsp. brachiata (= L. filiformis ) (Mexican sprangletop) is native to the S outhern half of the United States and much of Mexico, the Caribbean, and Central and South America. It

has naturalized in Africa and Australia.

Leptochloa virgata (L.) P. Beauv. (tropic sprangletop) is native to Texas

and Florida in the United States

, and also to Tamaulipas and Veracruz,

Mexico

, as well as to much of Central and South A merica and the

Caribbean.10 Molinia caerulea (L.) Moench (purple moor grass) is a perennial bunch grass native to temperate areas of Eurasia. It has been introduced as an

ornamental to northeastern Canada and the United States where it has invaded damp are as.

Muhlenbergia capillaris (Lam.) Trim. ( hairawn muhly) is a bunchgrass

native to the S outheastern United States and the Bahamas.

Oryza sativa L. (rice) is of Asian origin and is grown in tropical, subtropical, and warm

- temperate areas around the world.

Panicum amarum Elliot. ( bitter panicgrass) is native to coastal dunes along the Atlantic and g ulf coasts of the United States and the g ulf c oast of

northern Mexico

, as well as in swamp edges and wet sandy soils in this

range.

Panicum hirsutum Sw. (hairy panicum) is a native that grows from southern Texas to Argentina and in the Caribbean.

Panicum virgatum L. (switchgrass) is a native that grows mainly east of the Rocky Mountains from southern Canada through Central America and

in Cuba.

Pennisetum cilia re (L.) Link ( buf felgrass) is native to Africa, W estern Asia, and India. It has been introduced to and become highly invasive in

the S outhern United States and Mexico and elsewhere as a forage crop.

Phragmites australis (Cav.) Trin. ex Steud. (common ree d) is similar in appearance and habitat to A. donax

. P

. australis is found nearly worldwide in temperate and tropical wet habitats. An introduced e cotype from Europe is invading n ortheastern North America. This exotic ecotype is the target of a biologic al control program in the United States

.

Saccharum officinarum L. (s ugarcane) is grown in the S outh eastern
United States

, as well as in other tropical/subtropical regions throughout

the world. It is native to tropical Asia and Oceania.

Schizachyrium sco

parium (Michx.) Nash ( little bluestem) is native to most

of Canada

, the United States

, and northern Mexico.

Schoenoplectus maritimus (L.) Lye (alkali bulrush) grows from Canada

into South America

, as well as in Africa, Eurasia, and Oceania. It may

actual ly be native to Eurasia.

Sorghum bicolor (L.) Moench (sorghum) is a native of Africa that is grown through much of the world.11 Spartina alterniflora ( S. alterniflora ) Loisel . (smooth cordgrass) is an obligate wetland species native to saltmarshes along th e Atlantic c oa st of Canada, the Atlantic and g ulf coasts of the United States, the Caribbean, and northern South America to Uruguay. It is an introdu ced invasive along the Pacific c oast of California, Oregon, and Washington , as well as

in W estern Europe a nd New Zealand.

Spartina spartinae (Trin.) Merr. ex Hitchc. (Gulf cordgrass) is a native bunch grass that grows mainly along the Atlantic c oast of Florida, the g ulf

c oast of the United States

, and Mexico to Costa Rica. In South America it

is native to Ve nezuela, Argentina, and Paraguay.

Sporobolus wrightii Munro ex Scribn. (alkali sacaton) is a native growing

in Texas and Oklahoma

, west to California

, and south to central Mexico.

Tridens albescens (Vasey) Wooton & Standl. ( white t ridens) is native to

Te xas, Oklahoma, Kansas, New Mexico, Arizona, and northern Mexico.

Tripsacum dactyloides (L.) L. ( eastern gamagrass) is native to the E astern
and C entral United States

, and south through Mexico to northern South

America.

Triticum aestivum L. (whe at) origin ated in central and W estern Asia

, but is planted in many of the temperate areas of the world.

Typha domingensis Pers. (narrowleaf cattail) is an obligate wetland plant

native to the lower two

- thirds of the United States and south into much of

South Americ a. It grows throu gh much of the tropics and warm temperate

areas.

Uniola paniculata L. (sea oats) is a native that grows on sand dunes along the coast from Maryland to Veracruz, Mexico

, as well as in the Bahamas

and Cuba.

Zea mays L. (corn) is native to Mexico but is grown through much of the

world.



## IV

. Environmental Consequences

A. No Action

a. Beneficial Uses

A. donax is grown for woodwind reeds, although there is currently no commercial production in North America (Perdue

, 1958 ; Obataya and

Norimoto , 1995) . The highest quality reeds come from the native range in 1. Impact of Spread of

Arundo donax12 Europe. It is also used in basketry, for fishing rods, livestock fodder, and

medicine. Currently, the most sig nificant use of this plant is its proposed use as biofuel (Szabo et al.

, 1996). There are a few small

- scale research plantings of A. donax in Texas and Georgia. Use of A. donax as a biofuel has sparked considerable controversy in Florida, which may have caused entrepreneurs to consider establishing an Arundo plantation in Texas (Florida Native Plant Society

, 200 6 ). The use of invasive species as biofuels is considered to be extremely risky. Raghu et al. (200 6 ) presents

the case that the long

- term enviro nmental consequences of using invasive

spec ies will far outweigh the short

- term gains for energy use. USDA research on biofuels precludes the use of Federal dollars for research on invasive plants.

b. Nontarget Plants

Nontarget plants growing in r iparian areas are severely impacted by

A. donax throughout North America. A

. donax grows in dense stands that prevent normal regeneration of native riparian vegetation. In many areas,

A. donax is burned yearly to keep standing vegetation to a minimum. I n other areas, accidental wildfires enter riparian zones infested with

A. donax damaging riparian plants. In both cases native plants, especially trees that are not fire adapted, are killed by the hot fires. A

. donax

survives the wildfires due to its ext ensive below

- ground rhizomes. It regrows quickly after fires, shading out emerging seedlings, thus increasing its dominance over native riparian vegetation.

c. Ecosystem F unction

Widespread effects of A. donax on ecosystems have been documented on

seve ral continents

, including Australia, North America, Oceania, and Africa. The Global Invasive Species Database lists A. donax as one of the

worst 100 invaders (see http://www.issg.org/ database/species/ecology.asp?si=112 )

. A

. donax can increase sediment deposition in natural and manmade channels resulting in reduced channel depth and greater flooding (Frandsen and Jackson

, 1994). In addition, during flooding, debris dams of A. donax m ay collect adjacent to flood control structures, bridges, and culverts

, exacerbating flooding (Frandsen and Jackson

, 1994). A

. donax produces profuse quantities of biomass (Perdue, 1958 ; Sharma et al.

, 1998 ; Spencer et al.

, 2006) that are quite flammable at the end of the growing season. As a result, it has changed control of ecosystem processes in some Californian riparian

zones from flood

- regulated to fire

- regulated (Rieger and Kreager

, 1989).

d. Protected Species

A. donax threatens most native plan ts and

, thereby

, native wildlife growing in the same habitat. The least Bell’s vireo, s outhwestern willow13 flycatcher

, and y ellow

- billed cuckoo are negatively impacted by A. donax because it does not provide the structural habitat and food sources that

nat ive vegetation provides (Frandsen and Jackson

, 1994 ; Dudley and

Collins

, 1995). In Sonoma Creek, California, A

. donax was associated

with about 50 percent of the reduction in the total number and biomass of arthropods that w ere found on native vegetation (Herrera and Dudley

, 2003). Protect ed aquatic species ( such as the a rroyo to ad, r ed

- legged frog,

w estern pond turtle, Santa Ana sucker, arroyo chub, u narmored three

spined stickleback, t idewater goby, and steelhead trout ) are negatively

affected by A. don ax because it provides little shade over streams and leads to increased water temperatures that are unsuitable for wildlife (Hoshovsky

, 1988).

e. Human Health

There are a few reports of allergies to Arundo pollen. It is listed on www.pollenlibrary.com as a moderate allergen.

f. Water Usage

Large stands of A. donax can increase water loss from underground aquifers in semi

- arid regions due to a high evapotranspiration rate, which is estimated at roughly 3 ti mes greater than that of the native riparian vegetation. A. donax consumes an estimated 56,200 acre

- feet of water annually from the Santa Ana River alone (Zembal, 2007).

The continued use of chemical herbicides, and mechanical and biological

controls at current levels would be a result if the ―no action‖ alternative is

chosen.

a. Chemical Control

The most common herbicide used for A. donax is glyphosate which may require continued application for 3 to 5 years for local control (Newhouser

et a l., 1999; Dudley, 2000). The herbicide imazypyr is also used for control along ditches and canals. However, chemical control methods are not feasible for large

- scale infestations covering hundreds of river miles

, such as the infestation in the Bi

- Nationa l Rio Grande Basin. Broadcast applications of herbicides co uld have adverse impacts on non target vegetation if not carefully applied.

b. Mechanical Control

Mechanical methods of A. donax control include use of prescribed fire, heavy machinery (e.g. b ull dozer, H ydro

- axe, ), hand

- cutting, chipper, etc. Biomass removal may be necessary if there is a possibility that cut vegetation might create a flood hazard during high water events. Chipping 2. Impact from
Use of Other
Control

Methods14 is a costly method of removal. Equipment and labor are expen sive relative

to other forms of removal ; however, the small dry chips that are produced pose little threat in terms of regeneration

, and they do not form debris

dams. Biomass removal by vehicle is expensive and generally not preferred due to its lack of c ost

- effectiveness. The use of heavy machinery

, such as the Hydro

- axe
, is extremely expensive and slow, cutting only about 3 to 4 acres per day (Bell

, 1997). Mechanical

eradication with a backhoe has been ineffective because the rhizome fragments buried u nder the soil will readily re

- sprout. Prescribed burning

has not been successful because it cannot kill the rhizomes

, and generally

promotes A. donax regeneration over native riparian species.

c. Biological Control

The Arundo wasp, Tetramesa romana Wa lker (Hymenoptera: Eurytomidae) was approved for release in April 2009. It currently occurs in Texas and California. It is not expected that Tetramesa romana ( T. romana ) alone will completely control A. donax . However, the stem galling of A. donax cause d by T. romana results in shortened internodes, stunted stems, and sometimes death of the stems.

These environmental consequences may occur even with the implementation of the biological control alternative, depending on the efficacy of R. donacis to redu ce A. donax in the continental United States.



### B. Issue Permits for Environmental Release of

R. donacis

Host specificity of R. donacis to A. donax has been demonstrated through

scientific literatur e, field observations, and host

- specificity testing. If an insect species only attacks one or a few closely related plant species, the

insect is considered to be very host

- specific. Host specificity is an essential trait for a biological control organism proposed for

environmental release.

a. Scientific L iterature

Both the original description of R. donacis (as Targionia donacis , revised

as Rhizaspidiotus donacis by Ferris (1943) and other collections from the native range (reviewed by Balachowsky, 1932; 1951) in France (Balachowsky, 1930; 1933; 1951), Sp ain (Balachowsky, 1935; Gómez

Menor Ortega, 1958; Martin

- Mateo, 1983), Italy (Lupo, 1957), and North Africa (coastal Algeria) (Balachowsky, 1928) indicate that R. donacis has been collected only from A. donax , with the exception of one report from Turkey ( Uygun et al., 1998) indicating a collection from common reed ( Phragmites australis ). 1. Impact of

R. Donacis on Nontarget

Plants15 b. Field C ollections and O bservations

Extensive surveys by Alan Kirk (USDA

- ARS, European Biological Control Laboratory ( EBCL ) , Mont pelier, France) throughout the W est ern Mediterranean, including Morocco, confirmed the widespread presence of

R. donacis on A. donax . Occasionally, this scale was found on Arundo plinii in Spain.

c. Host Specificity Testing

(1) Site of Quarantine and Field Studies

Host

- specificity tes ts a re test s of how many plant species R. donacis

attacks/eats

. Field studies were conducted throughout Mediterranean Europe and in N orth America. Most studi es were conducted near the

ARS

– European Biological Control Laboratory in Montpelier, France

. R

. donacis is native within 37 miles of the research grounds at the Campus Baillarguet Internacional. Laboratory studies were conducted at the

USDA

– APHIS Mission Biological Control Laboratory, Mission/Edinburg,

T exas

.

(2) Test Plant List

( The list of pla nt species used for host

- specificity testing of R. donacis is

shown in appendix A

. )

A. donax belongs to the plant family Poaceae (grasses) and the subfamily

Arundinoideae. Representatives of all of the subfamilies closely related to Arundinoideae (C hl oridoideae, Centothecoidae, Panicoidae, and

Micrairoideae ) were included in the host range testing except for

Micrairoidea e which is not represented in North America. Representatives

from more distant subfamilies within the Poaceae ( Aristidoideae,

Danthon ioideae, Pooideae, and Bambusoideae ) were also tested.

Within the Arundinoideae are the following core genera: Arundo, Dregeochloa, Hakonechloa, Molinia, and Phragmites . Representatives from all of these genera were tested except Dregochloa , which i s found only in southern Africa, and Hakonechloa , an uncommon exotic, ornamental species in North America. A p lant in the genus Molinia w as obtained, but it is also a rarely used exotic ornamental. Of these genera, Phragmites is the most critical because it occurs with A. donax throughout a large part of its introduced range

, and R. donacis has been reported on Phragmites australis in the literature . There are no native Arundo species in North or South America. The only other Arundo species present in

N orth America is A. formosana

. This plant is native to Taiwan and is an uncommon, exotic, ornamental in the San Francisco Bay Area. None of16 the other Mediterranean Arundo species ( A. plinii

, A. collina

, or A.

mediterranea ) a re present in North America.

T o evaluate the genetic diversity of A. donax , the two dominant genotypes in the Rio Grande Basin (RGB) were collected from San Juan, Texas

, in the Lower Rio Grande Valley and Laredo, Texas, 150 miles upriver. The Laredo genotype is the dominant genotype i n the RGB above Laredo and

, therefore

, is representative of the vast biomass of the invasive population.

Considerable emphasis was placed on selection of Phragmites test plants. There is only one Phragmites species present in North America ( P.

australi s ), but there is a considerable body of knowledge associated with

P. australis because of its worldwide distribution and invasiveness in northeastern North America (Tewksbury et al., 2002). P opulations of

P. australis from Rhode Island, California, and Te xas were collected and used in testing

.

Within the Poaceae, the main agricultural grasses, including corn, wheat, sorghum, and rice were tested. Genetic material of thes e grasses was obtained from USDA

– ARS Germplasm Repositor ies in Idaho, Georgia,

and Colorado. Whole rice pla nts were obtained from the USDA

– AR S laboratory in Beaumont, T exas

.

Several habitat associates of A. donax were selected that represented plants that R. donacis could come in to contact with in the w estern or g ulf

c oast areas of Nor th America. All of the habitat associates are native non

economic species, except pecans, which are a native economic species.

Discussion of Host

- Specificity Testing

In quarantine host

- specificity testing, most plant species supported no

R. donacis scal es through any developmental stage. In no choice tests, there was low level survival and development of R. donacis on S

. alterniflora and three Leptochloa species , less than 1 percent as compared to 43 percent development to the adult stage on A. donax

. In additional testing of S. alterniflora n o settling or development occurred on the plant, confirming that it is not expected to be a host of R. donacis. In field host range studies in Europe, R. donacis was not found on any other plant than A. donax.

Qu arantine Host Range Tests (Goolsby, 2009)

. In n o c hoice t ests (host

- specificity tests where the target insect is offered only one test plant species and not offered the choice of either A. donax and the test plant species), 200 R. donacis crawlers were re leased on each test plant species. Crawlers that did not settle on plant tissues died within 2 to 3 days of

release and

, thus

, were not expected to be observed at the time of plant dissection, 3 to 4 months after release of crawlers onto each plant. Earl y17 second

- instar scales (sex not determinable) were uncommon on A. donax

, A. formosana, and non

-

Arundo plants and did not vary in abundance between plant species ( a ppendix B ). Late second

- instar females were also

uncommon on A. donax (observed on 4 of 29 s hoots), and did not differ in

abundance between A. donax and the one non

- Arundo plant on which they were observed, Cynodon dactylon ( appendix B ).

Adult males (indicated by empty scale coverings) were significantly more

abundant on A. donax than on any n on

- Arundo plant species, while not differing from A. formosana ( appendix B ). Adult males were 2.5

- fold

more abundant on A. donax (316 adult males found on 29 shoots) than on

S

. alterniflora (13 found on 3 shoots), and were 7 to 30

- fold less abundant

on 3 Leptochloa spp. than on A. donax ( a ppendix B )

. Live adult females, representing the most long

- lasting and damaging scale stage, were found on only one non

-

Arundo species, Leptochloa virgata , with three adults

found on two shoots. Live adult female abunda nce per L. virgata plant

was 41

- fold lower than on A. donax , on which 599 adult females were found on 29 shoots ( appendix B ). Arundo donax was 6.9

- fold higher than A. formosana in live adult female counts ( appendix B ).

As an additional measure of devel opment by females, counts of live and

dead adult females were combined. Combined living and dead adult

females were found on two Leptochloa species: L. fusca subsp. univervia ( three dead females on one of three plants tested) and L. virgata ( four dead

adu lt females, in addition to the three live females noted earlier, on one of the two plants tested). Dead adult females were also found on S

. alterniflora (total of 20 dead females found across two of three plants). These adults were originally reported as live because the grass leaf they were on died and it is not clear whether they would have survived. These values can be compared to A. donax , on which 669 live and dead adult females were found across 29 total plants. Average combined live and

dead adul t females per plant were 3.4

- fold higher on A. donax than on

S

. alterniflora , 6.6

- fold higher than on L

. virgata , and 23

- fold higher than

on L. fusca subsp. uninervia ( a ppendix B ).

Total live scales were significantly higher on A. donax than any other pla nt species ( a ppendix B ). Forty of the 47 n on

- Arundo plant species did

not support any R. donacis scales through any developmental stage. Total

live scales were 3

- fold more abundant on A. donax than on A. formosana

, 7.6

- fold more abundant than on S

. alter niflora , 11

- fold more abundant

than on Chasmanthium latifolium , 17 to 100

- fold more abundant than on Leptochloa spp., 55

- fold more abundant than on P

. australis (exotic Rhode Island, USA genotype), and 100

- fold more abundant than on Cynodon dactylon , all s ignificant differences in mean comparisons.

A followup no

- choice test was performed involving A. donax from Laredo, Texas, and the four non

-Arundo plant species on which small18 numbers of R. donacis males and/or females completed their immature developmen t in prior host range tests. These species were further challenged by releasing 1

, 000 crawlers on each plant. The plants were

dissected 3 months after crawler release. The results of the high rate tests

are shown in a ppendix C . Survival and development of R. donacis on S

. alterniflora and Leptochloa spp. was very low, less than 1 percent as compared to 43 percent development to the adult stage on A. donax

. Mortality of crawlers under field conditions is likely to be much greater, thus further limiting the host range on R. donacis

.

In August 2010, additional quarantine choice and dispersal tests were

conducted to ensure that S. alterniflora would not serve as a host for

R. donacis. Rhizaspidiotus donacis crawlers were given the choice to disperse, s ettle

, and develop on their host plant, A. donax , or the non target S. alterniflora

. In these studies, n o settling or development occurred on S. alterniflora

. In another study, t he ability of R. donacis crawler s to be wind dispersed from A. donax and then settle and develop on

S. alterniflora was tested. Although it was found in this study that

R. donacis crawlers can be dispersed by wind, they did not settle and develop on S. alterniflora

. These studies confirm that S. alterniflora is not expected to be at risk from R. donacis

.

Field H ost R ange S tudies (Goolsby, 2009)

. In f ield s urvey of non

targets in Mediterranean Europe , h undreds of the non target plant species

of concern were c ollected and dissected. N o R. donacis or any other diaspidid scales were observed on any L eptochloa fusca subsp

. uninervia plants collected in Valencia, Seville

, or Tortosa , Spain, w hereas

R. donacis was common on A. donax at the three sites. No R. donacis was observed on A. donax in the colder inland rice growing area of

Mer ida/Badahoz where L eptochloa fasicularis was found.

No R. donacis were observed on S partina versicolor at El Saler (Valencia). This site was the most intact natural area on the Mediterranean coast, and the two species have been growing together for

many thousands of years. R

. donacis was common on all the A. donax

stands in this natural area. In southeastern France

, near Leucate

, two populations of Spartina foliosa were collected and examined, one within

500 m and the second 6 cm from A. donax

. Chortin aspis subterranea (Diaspidae) individuals were collected from 4 of 11 stems at the second site, and heavy populations of R. donacis were observed on adjacent

A. donax . No R. donacis were observed on S. foliosa

.

In addition, other grasses growing with A. donax

, identified as Agropyrum, Cynodon, Elymus

, Thinopyrum, Panicum, and Chloris

, were sampled at the above locations in Spain. Ten to 30 of each species within 0.5 m of

R. donacis populations were collected, dissected

, and evaluated. No

R. donacis indi viduals were found on the above grass species.19 In a field host exposure test , 20 L eptochloa dubia plants were returned to quarantine facilities for dis section and inspection after 6 months in the field. Plants were green and in good shape. Individual l eaf blades and stems were separated and inspected for any evidence of R. donacis . No

R. donacis individuals of any life stage were detected. This indicates that despite repeated exposure to multiple cohorts of crawlers emanating from the adjacent A. dona

x, L. dubia was not a field host for the scale (Goolsby, 2009)

.

R. donacis is one of the most damaging insects to A. donax in its native

range. The scale attacks the rhizome and developing underground buds by feeding on plants cells that carry out photo synthesis and cellular respiration and can store food for the plant . Damage symptoms include

side shoot distortion with thin, brittle, short canes. Crawler feeding often

causes distortion and a witch’s broom effect (a n abnormal br ushlike growth of weak, closely clustered shoots ) . Other effects over time include gradual thinning, leaf reduction, and a sickly, yellowish

- clouded appearance of canes. The ov erall effect is diminished vigo r with A. donax stands characterized by thin, brittle, naked canes.

A ssessment of impact on A. donax by the previously released T

. romana combined with R

. donacis was conducted in a quarantine greenhouse study (Goolsby, 2009). T

. romana alone and T. romana plus R. donacis caused significant damage to A. donax by suppressi ng leaf and stem elongation and by stimulating the production of side branches during a 12

- week period . The R. donacis plus T. romana treatment produced only slightly greater plant impacts as compared to T. romana alone, most likely

because of the longer developmental time of R. donacis . The impact of

R. donacis from the crawler to late second instar is not as great as the effect caused by the larger adult female. A longer study that fully encompassed the entire 6

- month development period of R. donacis m ay have shown more impact by R. donacis combined with T. romana. No negative interactions were observed between the two biological control agents during the 12

- week study. Continued observation of the test plants

revealed that damage by R. donacis was si gnificant 4 to 6 months after release. Large colonies of the scale formed at the base of the rhizome, which appeared to furthe r suppress any regrowth, even 8 to 10 months

after release. These results are consistent with field observations in Europe. In Europe, R. donacis causes long

- term debilitation of A. donax

stands.

Once a biological control agent

, such as R. donacis

, i s released into the

environment and become s established, there i s a slight possibility that it could move from the target plant ( A. donax ) to attack nontarget plants

. Host shifts by introduced weed biological control agents to unrelated plants are rare (Pemberton, 2000). Native species that are closely related

to the target species are the most likely to be attacked (Louda et al., 2003)

. 3. Uncertainties Regarding the
Environmental
Release of

R. donacis 2. Impact of

R. donacis on A. donax20 If other plant species were to be attacked by R. donacis , the resulting effects could be environmental impacts that may not be easily reversed. Biological control agents

, such as R. donacis

, generally spread without intervention by man. In principle, therefore, release of th is biological control agent at even one site must be considered equivalent to release over the entire area in which potential hosts occur and in which the

climat e is suitable for reproduction and survival.

In addition, this agent may not be successful in reducing A. donax populations in the continental United States. Worldwide, biological weed control programs have had an overall success rate of 33 percent; succ ess rates have been considerably higher for p rograms in individual countries (Culliney, 2005). Actual impacts on A. donax by R. donacis will not be known until after release occurs and post

- release monitoring has been conducted. It is expected that R. do nacis will work together with the previously released biological control agent

, T. romana

, to reduce populations of A. donax

.

―Cumulative impacts are defined as the impact on the environment which results from the incremental impact of the action when ad ded to other past, present and reasonably foreseeable future actions regardless of what agencies or person undertakes such o ther actions‖ (40 CFR 1508.7).

Many Federal and State agencies, as well as private entities, conduct

programs to manage A. donax

, a s well as other invasive weeds. Chemical and mechanical methods, as described previously in this document, are used in a wide range of habitats. Some of these control programs are

listed below.

Dept. of Homeland Security, Customs and Border Protection : The Border Patrol is planning to use mechanical and chemical methods to control

A. donax along the U nited States and Mexican border in Webb County, Texas, to assist in law enforcement activities associated with illegal border crossings (DHS, 2008).

Dep t. of State, International Boundary and Water Commission (IBWC) , El
Paso, T exas: The IBWC use annual mowing along the sections of the Rio

Grande to manage access to the River.

U.S. Fish and Wildlife Service, International Services : Chemical control

is u sed to stop the spread of A. donax at the Cuatro Cienegas nature preserve in Coahuila, Mexico

U.S. Dept. of Interior, National Park Service, Big Bend National Park

, Texas: Park staff use a combination o f fire and herbicides to manage

A. donax

. 4. Cumulative Impacts21 Texas Dep t. of Parks and Wildlife, Bentsen State Park, Mission, T exas: Park staff use herbicides to control A. donax and Phragmites growing in

the alternate river channels.

Lower Rio Grande Valley Irrigation and Drainage Districts, Brownsville, Harlingen, Mercede s, McAllen, and La Hoya, T exas: A ll of the irrigation

districts report that they use mechanical control, shredders

, and backhoes

for control of A. donax along irrigation canals and drainage ditches.

Maverick Irrigation District, Eagle Pass, T exas: The d istrict reports the

use of mechanical and chemical control to manage A. donax along irrigation canals and drainage ditches.

Texas Dept. of Transportation (TXDot) , Austin, T exas: The S tate vegetation coordinato r reports that TXDot uses mechanical and chem ical control to maintain populations of A. donax growing along roadsides. The problem is most severe in south

- central Texas near College Station.

Team Arundo Del Norte

, California : A consortium of homeowner associations, municipalities

, and the State of California combine their resources to use chemical control, mechanical removal

, and revegetation to restore ecologically sensitive rivers and creeks in n orthern California.

Team Arundo Del Sur

, California : A consortium of homeowner associations, municip alities

, and the State of California combine their resources to use chemical control, mechanical removal and revegetation to restore ecologically sensitive rivers and creeks in s outhern California.

California Dept. of Transportation (CalDOT), Sacramento, C alifornia:

C alDOT uses mechanical and chemical control to manage A. donax alo ng highways and bridges in the S tate.

Private l andowners throughout the southern tier of the United States use a variety of methods to control A. donax where it has become inva sive on private land.

Santa Ana Watershed Association (SAWA), California: SAWA has removed over 2,000 acres of A. donax from the Santa Ana watershed to restore habitat for native species, including the southwestern willow flycatcher.

USDA, Agriculture R esearch Service is conducting releases of the previously released biological control agent T. romana in the vicinity of Laredo, Texas.

Release of R. donacis is not expected to have any negative cumulative impacts in the continental United States because o f its host specificity to22 A. donax . Effective biological control of A. donax will have beneficial effects for weed management programs, and may result in a long

- term,

non

- damaging method to assist in the control of A. donax , and prevent its spread into ot her areas potentially at risk from invasion.

Section 7 of the Endangered Species Act (ESA) and ESA’s implementing regulations require Federal agencies to ensure that their actions are not likely to jeopardize the continued existence of federally listed t hreatened

and endangered species or result in the destruction or adverse modification

of critical habitat.

A

. donax has been documented to be the cause of the extinction of endemic fish species in the Rio Nadadores in Coahuila, Mexico

, near Cuatro Ciene gas (McGaugh et al., 2006). This region is rich in biodiversity, including fresh water stromatolites. The U.S. Fish and Wildlife Service, Pronatura Noreste, and the University of Texas at Austin are trying to eradicate A. donax from the most sensitive ar eas of Cuatro Ciénegas Natural Area. In California, least Bells’ vireo ( Vireo bellii pusillus Coues) is threatened by A. donax invasion (Boose and Holt, 1999). On the Rio Grande, Correl’s false dragon head, Physostegia

correllii , is a rare species which is severely impacted by A. donax.

a. Plants

There are 13 federally listed species in the plant family Poaceae in the

continental United States. APHIS has determined that environmental

release of R. donacis will have no effect on Alopecurus aequalis v ar.
sonomensis (Sonoma alopecurus), Poa atropurpurea (San Bernardino bluegrass) and its designated critical habitat, Poa napensis (Napa bluegrass)

, or Zizania texana (Texas wild

- rice) and its designated critical

habitat. These species occur in either the subfamily Pooidae or Ehrhartordeae, both distantly related subfamilies to Arundinoideae. Some species belonging to the subfamily Pooideae were tested ( Elymus virginicus, Sporobolus wrightii , and Triticum aestivum ) but no development occurred on these plan ts. Alopecurus pratensis L. (meadow foxtail) is currently being tested against R. donacis as a surrogate for Alopecurus aequalis var. sonomensis. Preliminary results have indicated that no crawlers have settled on the plant (100 percent mortality of

craw lers (J. Goolsby, pers. comm.).

The remaining listed grass species occur in the subfamily Chlordoideae. In host specificity testing, there was some minor development on some species belonging to this subfamily ( Cynodon dactylon, Leptochloa spp.,

and S

. a lterniflora ). S pecies of Leptochloa and Spartina exist in the native range of the scale and were surveyed and challenged in a host exposure test. Neither these species nor other species of Chlorodoideae are hosts

for R. donacis in Europe. R. donacis wou ld be unable to survive on 5. Endangered Species Act23 Neostapfia colusana (Colusa grass), Orcuttia californica (California Orcutt grass), Orcuttia inaequalis (San Joaquin Orcutt grass), Orcuttia pilosa (hairy Orcutt grass), Orcuttia tenuis (slender Orcutt grass), Orcuttia

viscida (S acramento Orcutt grass), Tuctoria greenei (Greene’s tuctoria), or

Tuctoria mucronata (Solano grass) because part of their life cycle occurs in vernal pools. Orcuttia plants grow underwater for 3 months or more and have evolved specific adaptations for aqu atic growth (Keeley, 1998). Neostapfia colusana occurs in large or deep vernal pools with substrates of high mud content. Tuctoria greenei is known only from vernal pools in the Central Valley of California. Tuctoria mucronata is an annual grass that ge rminates in temporary pools, producing slender leaves that float on the water's surface, and then, when the pools dry out for the summer, producing shoots and flowers (the inflorescence is 1.5 to 6 cm long) (NatureServe, 2009). Finally, a ll of the above l isted vernal pool grasses are annual grasses. R. donacis is a terrestrial scale insect that feeds on rhizomes and stem node tissue of long

- lived, perennial Arundo spp. Rhizaspidiotus donacis has a 6 month or longer life cycle. The life cycle

of those ve rnal pool grasses would be too short to support the development

of R. donacis. Therefore, APHIS has determined that the release of

R. donacis may affect, but is not likely to adversely affect N. colusana

, O. californica

, O. inaequalis, O. pilosa

, O. tenui s, O. viscida, T. greenei,

or T. mucronata

.

Swallenia alexandrae (Eureka dunegrass), a perennial plant in the subfamily Chlordoideae, grows in an environment that is hostile to both

Arundo donax and R. donacis

. It is located in four dunes in the Eureka

V alley, Inyo County, California. All four populations are on lands managed by Death Valley National Park. Death Valley is the hottest and driest place in North America

. Summer temperatures often top 120 °F (49 °C). Average rainfall is less than 2 inches (5 cm). The high summer temperatures would be lethal to R. donacis , which is a Mediterranean

ins ect (J. Goolsby, pers. comm.). The Eureka dunes a lso experience

winter freezes. The distribution of R. donacis in Europe is limited to only

the climates war m enough for citrus to be grown. Therefore, both the high

and low temperature extremes would be unsuitable for establishment of

R. donacis (J. Goolsby, pers. comm .). Therefore, APHIS has determined

that release of R. donacis may affect, but is not likely to adversely affect

S. alexandrae.

b. Animals

A. donax has been found to be used by some wildlife, although it provides little value for native wildlife in comparison to native vegetation, especially when it forms large, monotypic stands. Two endanger ed bird species, least Bell’s vireo ( Vireo bellii pusillus ) and the southwestern willow flycatcher ( Empidonax traillii extimus ), have been found to use

A. donax as a nest host (Pike et al., 2002; Kus, 2000). However, the24 recovery plan for the southwestern willow flycatcher indicates that this bird rarely nests in A. donax

, and also indicates that in California, A.

donax is spreading rapidly, forming dense, monotypic stands unsuitable for flycatchers (FWS, 2002). Least Bell’s vireos have been found nesting

on A. donax along the Santa Clara River and the San Luis Rey River. In

the U.S. Fish and Wildlife Service’s 5

- year review of the least Bell’s vireo (FWS, 2006), habitat loss and invasion of riparian habitat by introduced exotic plant species (primarily A . donax ) is listing factor 1 for the species

. R. donacis is not expected to cause rapid, drastic reduction of A. donax

, but could potentially decrease the reproductive capacity of A. donax

. Thus, A. donax would not be rapidly removed from the environment

, leaving nesting habitat for these species. Therefore, release of R. donacis may affect, but is not likely to adversely affect

, nesting by the least Bell’s vireo or the southwestern willow flycatcher

, and may potentially benefit their designated critical habitat a s A. donax does not provide suitable

habitat for these birds.

In Texas, A. donax provides migratory habitat for the Gulf Coast jaguarundi ( Herpailurus (= Felis ) yagouaroundi cacomitli ) and ocelot ( Leopardus ( =Felis ) pardalis ). However, R. dona cis is not expected to cause rapid, drastic reduction of A. donax , but could potentially diminish the vigor of A. donax, resulting in stands which are characterized by thin

brittle naked canes . Thus, A. donax would not be rapidly removed from

the environm ent, leaving migratory cover for these species. Therefore,

release of R. donacis may affect, but is not likel y to adversely affect the gulf c oast jaguarundi or ocelot.

S. alterniflora is an important component of the wintering habitat of the whooping cra ne ( Grus americana ). In additional host specificity testing conducted in August 2010, R. donacis did not develop on S. alterniflora. Therefore, APHIS has determined that release of R. donacis may affect, but is not likely to adversely affect the whooping crane or its critical

habitat.

APHIS submitted a biological assessment to the U.S. Fish and Wildlife Service (Service) in June 2009 and again in January 2010, requesting Service concurrence. Numerous email and telephone communications

have occurred betw een APHIS and the Service to clarify aspects of the

release of R. donacis . In a letter dated September 13, 2010, the Service

concurred with APHIS’s determinations that release of R. donacis may affect, but is not likely to adversely affect, the plants N. colusana

, O. californica

, O. inaequalis, O. pilosa

, O. tenuis, O. viscida, T. greenei, T.

mucronata, and S. alexandrae, or the animals V. bellii pusillus

, E. traillii

extimus

, L. pardalis, H. yagouaroundi cacmitli, and G. americana or their designated crit ical habitats.25 

## V. Other Issues

Consistent with Executive Order (EO) 12898, ―Federal Actions to Address

Environmental Justice in Minor ity Populations and Low

- I ncome Populations,‖ APHIS considered the potential for disproportionately high

and adverse human health or environmental effects on any minority populations and low

- income populations. There are no adverse

environmental or human health effects from the field release of

R. donacis

, and the release will not have disproportionate adverse effects to any minority or low

- income populations.

Consistent with EO 13045, ―Protection of Children From Environmental Health Risks and Safety Risks,‖ APHIS considered the potential for disproportionately high and adverse environmental health and safety risks to children. No circumstances that would trigger the need for special

environmental reviews are involved in implementing the preferred alternative. Therefore, it is expected that no disproportionate effects on children are anticipated as a consequence of the field release of R. donacis

.

EO 13175, ―Consultation and Coordination with Indian Tribal Governments,‖ was issued to ensure that there would be ―meaningful consultation and collaboration with tribal officials in the development of

Fe deral policies that have tribal implications....‖

APHIS is consulting and collaborating with Indian tribal officials to ensure that they are well

- informed and represented in policy and program decisions that may impact their agricultural interests in accord ance with EO 13175, ―Consultation and Coordination with Indian Tribal

Governments.‖26 

## V I

. Agencies , Organizations, and Persons
Consulted

The Technical Advisory Group for the Biological Control Agents of Weeds (TAG) recommende d the release of R. donacis on July 6, 2009

. TAG members that reviewed the release petition (Goolsby, 2009) included representatives from the Bureau of Indian Affairs, APHIS, Cooperative State Research, Education, and Extension Service, Forest Service, U. S. Geological Survey, Environmental Protection Agency, U .S. Army Corps of Engineers, Bureau of Land Management, Bureau of Reclamation, the National Plant Board, and representatives from Canada and Mexico.

This EA was prepared and reviewed by APHIS. The addresses of participating APHIS units, cooperators, and consultants (as applicable)

follow.

U.S. Department of Agriculture Animal and Plant Health Inspection Service Policy and Program Development

Environmental Services 4700 River Road, Unit 149

Riverda le, MD 20737

U.S. Department of Agriculture Animal and Plant Health Inspection Service Plant Protection and Quarantine Pest Permitting 4700 River Road, Unit 133 Riverdale, MD 20737

U.S. Department of Agriculture Kika de la Garza Subtropical Agricultur al Research Center

Beneficial Insects Research Unit 2413 E. Hwy. 83 Weslaco, TX 7859627 

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Order Family Sub

- family Scientific N ame Common

N ame Indigenous

to U

. S

. Indigenous

to Mexico Grain/

Forage Ornamental Habitat

Associate

Cyperales Poaceae Arundinoideae Arundo donax L . Laredo, TX giant reed No No No Yes

-

― ― ― Arundo donax L. San Juan,

TX giant reed No No No Yes

-

― ― ― A. formosana Hack. fountain reed No No No Yes No

― ― ― Phragmites australis (Cav.)
Trin. ex Steud. Rhode Island (exotic European ecotype) common

r eed No No No No No

― ― ― Phragmites australis (Cav.)
Trin. ex Steud.

Mercedes

, TX common reed Yes Yes No No Yes

― ― ― Phragmites australis (Cav.)
Trin. ex Steud.
San Benito

, TX common reed Yes Yes No No Yes

― ― ― Phragmites australis (Cav.)

Trin. ex Steud. Colorado River, CA common reed Yes Yes No No Yes

― ― ― Molinia caerulea (L.) Moench Moore grass No No No Yes No

― ― Aristidoideae Aristida purpurea Nutt. var

. longiseta (Steud.) Vasey red three

awn Yes Yes No No No

― ― Centothecoideae Chasmant hium latifolium (Michx.) Yates inland sea

oats Yes Yes No Yes Yes

― ― Chloridoideae Bouteloua hirsuta Lag. hairy grama Yes Yes Yes No No

― ― ― Cynodon dactylon (L.) Pers. Bermuda

grass No No Yes Yes Yes

― ― ― Dichanthelium acuminatum (Sw.) Gould and C lark tapered rosette grass Yes Yes Yes No No

― ― ― Eragrostis intermedia Hitchc. plains lovegrass Yes Yes Yes No No

― ― ― Eragrostis spectablilis (Pursh)
Steud. purple lovegrass Yes Yes Yes Yes No

― ― ― Leptochloa dubia (Kunth)

Nees green sprangleto p Yes Yes Yes No No― ― ― Leptochloa fusca (L.) Kunth subsp. uninervia (J. Presl) N.
Snow Mexican sprangletop Yes Yes No No No

― ― ― Leptochloa panicea (A. Retzius) J. Ohwi subsp.

B rachiata red sprangletop Yes Yes No No No

― ― ― Leptochloa virgata (L.) P.

Beauv. tropic sprangletop Yes Yes No No No

― ― ― Muhlenbergia capillaris (Lam.) Trim. hairawn muhly Yes Yes Yes Yes No

― ― ― Spartina alterniflora Loisel. smooth cordgrass Yes No? No No Yes

― ― ― Spartina spartinae (Trin.)

Merr. ex Hitchc. Gulf

co rdgrass Yes Yes No No Yes

― ― ― Tridens albescens (Vasey)
Wooton & Standl. white Tridens Yes Yes Yes No Yes

― ― ― Uniola paniculata L. sea oats Yes Yes No No Yes

― ― Danthonioideae Cortaderia selloana (Schult. & Schult. f.) Asch. & Graebn. pampas
grass No No No Yes No

― ― ― Danthonia spicata (L.) P.
Beauv. ex Roem. & Schult. poverty oatgrass Yes Yes Yes No No

― ― Panicoideae Andropogon glomeratus (Walter) Britton et al. bushy

bluestem Yes Yes Yes Yes Yes

― ― ― Digitaria cognata (Schult.) Pilg. fal l witchgrass Yes Yes Yes No No

― ― ― Panicum amarum Elliot. bitter panicgrass Yes Yes Yes No No

― ― ― Panicum hirsutum Sw. hairy panicum Yes Yes No No Yes

― ― ― Panicum virgatum L. switchgrass Yes Yes Yes Yes No

― ― ― Pennisetum ciliare (L.) Link b uffelgrass No No Yes No Yes

― ― ― Saccharum officinarum L. sugarcane No No Yes No No

― ― ― Schizachyrium scoparium (Michx.) Nash little

bluestem Yes Yes Yes Yes Yes― ― ― Sorghum bicolor (L.) Moench sorghum No No Yes No No

― ― ― Tripsacum dactyloides (L.) L. eastern

gamagrass Yes Yes Yes No Yes

― ― ― Zea mays L. corn No No Yes No No

― ― Pooideae Elymus virginicus L. Virginia wildrye Yes No Yes No Yes

― ― ― Sporobolus wrightii Munro ex
Scribn. alkalai

sacaton Yes Yes Yes No Yes

― ― ― Triticum ae stivum L. wheat No No Yes No No

― ― Bambusoideae Arundinaria gigantea (Walter)

Muhl. giant cane Yes No No Yes Yes

― ― ― Oryza sativa L. rice No No Yes No No

― Cyperaceae

---- Cyperus articulatus L. jointed flatsedge Yes Yes No No Yes

― ―

---- Schoenopl ectus maritimus (L.) Lye alkali bulrush Yes? Yes? No No Yes

Eriocaules Eriocaulaceae

---- Eriocaulon decangulare L. tenangle pipewort Yes Yes No No No

Typhales Typhaceae

---- Typha domingensis Pers. narrowleaf

cattail Yes Yes No No Yes

Arecales Arecace ae

---- Sabal mexicana Mart. Rio Grande palmetto Yes Yes No Yes Yes

Juglandales Juglandaceae

---- Carya illinoinensis (Wangenh.) K. Koch pecan Yes Yes Yes Yes Yes

Salicales Salicaceae

---- Salix exigua Nutt. narrowleaf

willow Yes Yes No No Yes

Asterales Asteraceae

---- Baccharis neglecta Britton dryland

Baccharis Yes Yes No No Yes

― Oleaceae

---- Fraxinus berlandieriana DC. Rio Grande

ash Yes Yes No Yes YesAppendix B . Results of N o
- C hoice H ost Range T ests for Rhizaspidiotus donacis (Goolsby, 2009). ( Values are mean numbers of scale insects per plant

. * )

Test Plant Species Reps Live Whitecaps/ Early 2nd

Instar Live Late

2nd Instar Adult

Male** Live Adult

Female Live+Dead

Adult Female Total Live

All Stages

mean ±SE mean ±SE mean ±SE mean ±SE mean ± SE mean ±SE

Arundo donax Laredo, TX 13 2.30±1.99 0.85±0.48 9.62±2.83 24.15±7.10 27.23±7.66 37.15±10.71

Arundo donax
San Juan TX 16 0.38±0.38 0 11.94±2.34 17.81±4.56 19.69±4.60 30.13±5.60

Arundo donax pooled Laredo and
San Juan, TX 29 1.24±0.92 a 0.38±0.22 a 10.90±1.79 a 20.66±4.02 a 23.07±4.24 a 33.28±5.63 a

Arundo formosana 3 0 0 7.33±3.67 a 3.00±1.53 b 5.00±2.89 b 11.00±5.57 b

Phragmites

australis
Charlestown RI (Exotic European

e cotype) 5 0.40±0.4 a 0 0.20±0.20 b 0 0 0.6 0±0.60 b

Phragmites

australis

Mercedes

, TX 4 0 0 0 0 0 0

Phragmites

australis
San Benito

, TX 3 0 0 0 0 0 0

Phragmites

australis
Colorado River CA 6 0 0 0 0 0 0

Molinia caerulea 3 0 0 0 0 0 0

Aristida purpurea

var

. longiseta 3 0 0 0 0 0 0

Chasmanthium

latifolium 2 0.50±0.50 a 0 0 0 0 0.50±0.50 b

Bouteloua hirsuta 3 0 0 0 0 0 0

Cynodon dactylon 3 0 0.33±0.33 a 0 0 0 0.33±0.33 b

Dichanthelium

acu minatum 3 0 0 0 0 0 0

Eragrostis

intermedia 3 0 0 0 0 0 0

Eragrostis

sp ectablilis 3 0 0 0 0 0 0

Leptochloa fusca subsp. uninervia 3 0.33±0.33 a 0 1.00±1.00 b 0 1.00±1.00 b 1.33±1.33 b

Leptochloa panicea subsp.

B rachiata 3 0 0 0.33±0.33 b 0 0 0.33±0.33 b

Leptochloa virgata 2 0 0 0.50±0.50 b 1.50±1.50 b 3.50±3.50 b 2.00±2.00 bMuhlenbergia

Capillaris 3 0 0 0 0 0 0

Spartina alterniflora 3 0 0 4.33±4.33 b 0 6.67±6.17 b 4.33±4.33 b

Spartina spartinae 3 0 0 0 0 0 0

Tridens albescens 3 0 0 0 0 0 0

Uniola paniculata 3 0 0 0 0 0 0

Cortaderia selloana 5 0 0 0 0 0 0

Danthonia spi

cata 1 0 0 0 0 0 0

Andropogon glomeratus 3 0 0 0 0 0 0

Digitaria cognata 3 0 0 0 0 0 0

Panicum amarum 3 0 0 0 0 0 0

Panicum hirsutum 3 0 0 0 0 0 0

Panicum virgatum 3 0 0 0 0 0 0

Pennisetum ciliare 3 0 0 0 0 0 0

Saccharum
officinarum 3 0 0 0 0 0 0

Schizachyrium scoparium 3 0 0 0 0 0 0

Sorghum bicolor 3 0 0 0 0 0 0

Tripsacum dactyloides 3 0 0 0 0 0 0

Zea mays 3 0 0 0 0 0 0

Elymus virginicus 1 0 0 0 0 0 0

Sporobolus wrightii 3 0 0 0 0 0 0

Triticum aestivum 3 0 0 0 0 0 0

Arundinaria gigantea 3 0 0 0 0 0 0

Oryza sativa 3 0 0 0 0 0 0

Cyperus articulatus 3 0 0 0 0 0 0

Schoenoplectus

maritimus 3 0 0 0 0 0 0

Eriocaulon decangulare 3 0 0 0 0 0 0

Typha domingensis 4 0 0 0 0 0 0

Sabal mexicana 3 0 0 0 0 0 0

Carya illinoinensis 3 0 0 0 0 0 0

Sali x exigua 3 0 0 0 0 0 0

Baccharis neglecta 3 0 0 0 0 0 0

Fraxinus

berlandieriana 3 0 0 0 0 0 0

* Two hundred crawlers placed on each plant. Means within the same column with the same letter are not significantly different in

least

- square comparisons of means to pooled A. donax from Laredo and San Juan, TX (in bold above) (P > 0.05).
** Completion of male development to the winged adult stage is inferred from empty 2 nd instar scale cove r.Appendix C. Results of No

- Choice Host Range Tests for Rhizaspidi otus donacis in which 1,000 Crawlers Were Released Per Plant (Goolsby, 2009). ( Values are mean numbers of scale insects per plant.* )

Test Plant Species Rep s Live

Whitecaps/ Early 2nd

Instar Live Late

2nd Instar Adult

Male** Live Adult

female Live+Dead

Ad ult

Female Total Live

All Stages

mean ±SE mean ±SE mean ±SE mean ±SE mean ±SE mean ±SE

Arundo donax Laredo, TX 2 12.5±8.5 a 6.00±0.00 249±24.0 a 129±40.0 a 177±53 a 398±25.5 a

Leptochloa
fusca subsp.

uninervia 3 0 0 1.00±1.00 b 0 0.67±0.67 b 1.00±1.00 b

Leptochloa panicea subsp.

brachiata 3 0.33±0.33 b 0 1.67±1.67 b 0 7.00±7.00 b 2.00±1.53 b

Leptochloa virgata 2 0 0 1.50±1.50 b 5.00 ±5.00 b 6.50±6.50 b 6.50±6.50 b

Spartina
alterniflora 3 0 0 0 0.33±0.33 b 1.67±0.33 b 0.33±0.33 b