United States Department of Agriculture

Marketing and Regulatory Programs

Animal and

Plant Health Inspection
Service 

# Field Release of the Gall Wasp

, Aulacidea

subterminalis (H ymen optera: Cynip idae)

, for Biological
Control of Invasive

Hawkweeds ( Hieracium spp.) in the Continental
United States

Environmental Assessment, January 2011 United States Department of Agriculture

Marketing and Regulatory Programs

Animal and

Plant Health Inspection
Service

# Field Rele ase of the Gall Wasp,

Aulacidea subterminalis (Hymenoptera: Cynipidae), for Biological Control of Invasive

Hawkweeds ( Hieracium spp.) in the
Continental United States

Environmental Assessment, January 2011

Agency Contact: Shirley Wager

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

– 1236

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## Table of Contents

I

. Purpose and Need for the Proposed Action

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

II

. Alternatives

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

I II

. Affected Environment

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

I V. Environmental Consequences

................. ........................... 1 2

V. Other Issues

................................ ............. ........................... 2 0

VI

. Agencies, Organizations, and Individuals C onsulted

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

VI I. References

................................ ............... ........................... 2 3

Appendix 1

................................ ............... ........................... 29 Appendix 2

................................ ............... ........................... 38 Appendix 3

................................ ............... ........................... 46 Appendix 4

................................ ............... ........................... 48 Appendix 5

................................ ................ ........................... 521



## I. Purpose and Need for the Proposed

Action

The U.S. Department of Agriculture (USDA), Animal and Plant Health Inspe ction Service (APHIS), Plant Protection and Quarantine (PPQ), Pest Permitting Branch (PPB) is proposing to issue permit s for release of the hawkweed gall wasp

, Aulacidea subterminalis (H ymen optera: Cyn pidae )

. Th e agent would be used by the appli cant for t he biological control of the

hawkweeds Hieracium pilosella, H. aurantiacum, H. floribundum, and H. flagellare in the continental United States . Before permit s are issued for

release of A. subterminalis

, the APHIS

– PPQ

, PPB must analyze the potential impact s of the release of this agent into the continental United

States.

This en vironmental assessment 1 (EA) has been prepared, consistent with USDA, APHIS' National Environmental Policy Act of 1969 (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 A.

subterminalis to control infestations of hawkweeds within the continental

United States . This EA consid ers the potential effects of the proposed action and its alternatives, including no action.

The applicant’s purpose for releasing A. subterminalis is to reduce the severity of infestations of invasive hawkweeds in the United States

. There are many specie s of non

- native, invasive hawkweeds in North America. These species originated in Europe, which is the native range to a massive complex of species, subspecies, and varieties of Hieracium

. Invasive hawkweeds were probably introduced into the eastern U nit ed States and Canada during the 1800s

. Several hawkweed species are considered noxious in many western States

. Introduced hawkweeds are highly competitive and relatively free of insects and pathogens in North America. These species out compete native and desirable vegetation, forming near monocultures and limiting economic use of infested land.

Existing management options for management of invasive hawkweeds are expensive, temporary, and have nontarget impacts. For these reasons

, the applicant has a n eed to release A. subterminalis

, a host

- specific, biological control organism for the control of invasive hawkweeds, into the

environment

.

1 Regulations implementing the National Envi ronmental Policy Act of 1969 (42

United States Code 4321 et seq. ) pro vide 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 th e proposed action and alternatives, and a listing of agencies and persons consulted.” 40 CFR § 1508.9.2



## II . Alternatives

This section will explain the two alternatives available to the PP B

— no action and issuance of pe rmits for environmental release of A.

subterminalis

. Although the PPB ’s alternatives are limited to a decision on whether to issue permit s for release of A. subterminalis , other methods

available for control of hawkweeds are also described. These control methods are not decisions to be made by the PPB

, and their use is li kely to
continue whether or not permit s are issued for environmental release of A.

subterminalis , depending on the efficacy of A. subterminalis to control

hawkweeds . These are methods pr esently being used to control

hawkweeds by public and private concerns.

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

this third alternative, the PPB would have issue d permit s for the field

release of A. subterminalis ; howev er, the permit s would contain special provisions or requirements concerning release procedures or mitigating

measures. N o issues have been raised that would indicate special provisions or requirements are necessary

.



### A. No A ction

Under the no action al ternative, the PPB would not issue permit s for the

field release of A. subterminalis for the control of invasive hawkweeds

. The release of this biological control agent would not take place. The following methods are presently being used to control hawkw eeds ; these

methods will continue under the ―No Action‖ alternative and will likely continue even if permit s are issued for release of A. subterminalis

, depending on the efficacy of the organism to control invasive hawkweeds

.

Hawkweeds may be controlled by using herbicides. Herbicides

, such as
2,4

- D, clopyralid, aminopyralid, and picloram have resulted in the greatest degree of control when applied at the normally recommended rate for perennial pasture weeds (Noe l et al. , 1979; 1992 a ; Wilson et al., 1997 ; 2005 ; 2006). Studies conducted at the University of Idaho showed that

over 50 percent control was achieved for 6 years following treatment with

a 1 pint per acre rate of clopyralid (Lass and Callihan

, 1992). Similar

results were achieved usi ng picloram at the rate of 0.25 to 0. 5 pounds of active ingredient per acre

. Other herbicides either failed to control meadow hawkweed or suppression was for less than 3 years (Lass and

Callihan

, 1992 ; Miller et al.

, 19 9 8). More recently

, aminopyralid (MilestoneTM) has been recommended as an effective herbicide ( http://www.msuextension.org/ruralliving/Dream/PDF/hawk.pdf last

accessed March 23, 2010 ).

Mechanical control of invasive hawkweeds has had limited success. 1. Chemical

Control

2. Mechanical
Control3 Digging the plants or otherwise disturbing the stolons, rhizomes, or roots only serves to spread the weed because plants can grow from buds on small root, stolon, and rhizome fragments. A stolon is a shoot that bends to the groun d or that grows horizontally above the ground and produces

roots and shoots at the nodes

. A rhizome is similar to a stolon and is a horizontal, usually underground

, stem that often sends out roots and shoots

from its nodes

. Disturbance by machinery sprea ds the weeds across the

field. Local disturbances caused by grazing livestock, ungulates, and rodents also enhance the rate of spread of hawkweed. In lawns, mowing

does not kill invasive hawkweeds because the low

- lying stolons and rhizomes are missed by the mower blades. Although mowing prevents seed production by removing flowering stems, repeated mowing encourages faster vegetative spread (Callihan et al.

, 19 97)

.

When perennial grasses, legumes, and other beneficial forbs are present in the plant c ommunity, fertilizers can help control hawkweed by increasing the competitive ability of the more desirable species. This may be particularly important on rangelands and pastures because these lands are generally not priority areas for supplemental fertil ization

, and soil nitrogen levels may be inadequate for optimal grass health. Marked reductions of hawkweed density and vigor have been obtained by fertilizer treatments in the United States (Reader and Watt

, 1981), Canada (Hay and Ouellette

, 1959), and N ew Zealand (Scot t et al., 1 990) when competing vegetation is

present. However

, Reader and Watt (1981) found that repeated fertilizer treatments had no effect on dense patches of hawkweed that contained few grasses or other forbs. Depending on soil produc tivity and grass condition, a single nitrogen application may be sufficient for grasses to competitively suppress hawkweed growth for 3 to 5 years (Reader

, 1990).

Five species of Hieracium

- specific insects have been tested and released for the biological control of hawkweeds in New Zealand. They are:

( 1. ) Aulacidea subterminalis (Insecta: Hymenoptera: Cynipidae)

— hawkweed gall wasp ; ( 2. ) Cheilosia psilophthalma ( Insecta: Diptera: Syrphidae)

—hawkweed

crown

- feeding hover fly ; ( 3. ) Cheilosia urbana (Inse cta: Diptera: Syrphidae)

—hawkweed root

feeding hover fly ; ( 4. ) Macrolabis pilosellae (Ins ecta: Diptera: Cecidomyiidae)

—hawkweed stem gall midge ; and

( 5. ) Oxyptilus pilosellae (Insecta : Lepidoptera: Pterophoridae)

— hawkweed plume moth

.

None of these ins ects have been released in North America. An additional

Aulacidea wasp
, besides A. subterminalis

, is being considered as a bio logical control candidate for release in North America

. Aulacidea 3. Cultural

Control

4. Biological

Control4 pilosellae , a wasp that forms galls on stems, leaves

, and stol ons of

hawkweeds

, i s currently undergoing testing and appears to be host

- specific (Littlefield et al. 20 08)

.



### B

. Issue P ermit s for E nvironmental R elease of
A. subterminalis

Under this alternative, the PPB would issue permit s for t he field release of

the gall wasp

, A. subterminalis

, for the control of invasive hawkweeds

. Th ese permit s would contain no special provisions or requirements concerning release procedures or mitigating measures.

Biological Control A gent I nformation

Phy lum: Arthropoda

Class: Insecta Order: Hymenoptera Superfamily: Cynipoidea Family: Cynipidae Subfamily: Cynipinae Tribe: Aylacini

Genus: Aulacidea Species : A. subterminalis Niblett

a. Native R ange

Aulacidea subterminalis is fairly common and widesprea d on H. pilosella in Northern Europe (Syrett et al., 1998). Fauna Europaea (2007) records

A. subterminalis as present in Britain, France, and Germany. In its native habitat, A. subterminalis occurs on H. pilosella inhabiting arid, nutrient poor grassland s, poorly fertilized upland pastures, inland dunes, and man

made heaths (Ellenberg

, 1988).

b. Other A reas of I ntroduction

A

. subterminalis is one of five insect bio logical control agents introduced to New Zealand for suppression of H. pilosella (Syre t t et al., 2 001). In New Zealand, A. subterminalis was approved for import and release in 1998, and was first released in 1999. It has since been released at 99 sites throughout the North and South Island, with establishment confirmed at approximately 37 percent of these sites (Aspinall , 2006; Smith et al., 2007). The failure of many releases was due to drought conditions following the release or site disturbance due to cropping or herbicide treatment (Sm ith et al., 2007).

c. Expected A ttainable R ange of A. subterminalis in North 1. Taxonomy

2. Geographical Range of A.

subterminalis5 America

A

. subterminalis is fairly common and widespread on H. pilosella in Northern Europe and it is also establishing well in more moist areas of New Zealand, but is not well adapted to survive in dry or droughty

environment s where plants may senesce early ( Littlefie l d et al., 200 8 ). Climate matching using CLIMEX Version 1.1 (CSIRO Australia) suggests that the wasp’s potential range in North America should match much of the distributions of the targeted Hieracium species (Li ttlefie ld et al., 2008)

.

A. subterminalis is parthenogen et ic ( a form of asexual reproduction in which females produce eggs that develop without fertilization by males ). Eggs are laid into the stolen tips. Eggs a re milky

- white in color, 0.24

millimeters ( mm ) long and 0.09 mm wide and have a stalk appro ximately 1.18 mm long

. Larvae develop inside the developing stolon

- tip gall. Galls are abnormal outgrowths of plant tissues and can be caused by various parasites, including insects

. Galls are about 4.5 mm in diameter (Klöppel

et al.

, 2003), but gall size is dependent upon the number of larval chambers

present. Galls become evident approximately five weeks after the plant is

expos ed to the female wasp

. G alls continue to enlarge for an additional

5 weeks (Littlefield et al. , 2008 ). Mature larvae are somewhat fusiform (tapered at each end, spindle

- shaped) , with a distinctive, unpigmented

head. The wasp overwinters in the larval stage. Pupation occurs in April, and adult wasps emerge from the galls from t he beginning of May to the

end of June in Switzerland. A. subterminalis has one generation per year. Adults are generally short lived; up to a week under ambient laboratory

conditions.



## III

. Affected Environment

A. Target Weeds

( 1. ) Scientific name : Hieracium pilosella L. Family: Asteraceae Synonyms: none

Common name: Mouse ear hawkweed

( 2. ) Scientific name: Hieracium aurantiacum L. Family: Asteraceae Synonyms: H. brunneocroceum Pugsley. Common name: Orange hawkweed, Grim the Collier 3. Life History of

A.

subterminalis6 ( 3. ) Sc ientific name: Hieracium floribundum Wimm. & Grab. Family: Asteraceae Synonyms: none Common name: King devil hawkweed

( 4. ) Scientific name: Hieracium x flagellare Willd. ( caespitosum x pilosella ) Family: Asteraceae Synonyms: Hieracium x duplex

, H. x macr ostoloum Varieties: cernuiforme, flagellare, glatzense Common name: Whiplash hawkweed

Introduced hawkweeds are perennial plants that contain a milky sap and are generally stoloniferous (plants that bear or form stolons)

. Hieracium piloselloides and H. gl omeratum are the only non

- stoloniferous introduced species. Each young plant consists of a rosette of 5 to 12 hairy leaves arising from a short, thick rhizome with a shallow, fibrous root system. The flowers are yellow or orange ( H. aurantiacum is the on ly orange

flowered species). New plants begin as seedlings or as leaves sprouting from stolons, rhizomes (Thomas and Dale

, 1974)

, and/or roots (Peterson

, 1979). Juvenile plants consist of low

- lying rosettes that develop into flowering plants as erect, sl ender stems arise from the rosette center.

All of the invasive hawkweeds reproduce asexually by apomixis (asexual seed production) and by vegetative spread by stolons, rhizomes, and root

buds. Orange hawkweed sends out from three to eight long, slender stolons along the soil surface. Meadow hawkweed also produces long, slender stolons, but some of its vegetative structures grow as shallow, underground r hizomes

. Stolons and rhizomes, initiated from buds at the base of rosette leaves, begin to grow when the plant initiates flowering. Once established, vigorous stolon growth quickly expands the colony, forming dense patches that can have as many as 3,200 plants per square yard. The slender, leafy stolons elongate through the summer and form daughter ros ettes at their tips (Thomas and Dale

, 1974). Hawkweeds regrow each year from short, below

- ground rhizomes. In H. piloselloides

, axillary buds develop into secondary flowering shoots rather than stolons.

Invasive hawkweeds also occasionally produce see ds sexually by periodic pollination and outcrossing. At lower elevations

, flowering occurs around

mid

- June and seeds ripen by early August. Mature seeds can germinate as soon as they are released from the plant (Stergios

, 1976). Studies have

shown that seeds are viable in the soil for up to 7 years (Panebianco and

Willemsen

, 1976). Invasive hawkweeds have relatively short life cycles, completing a generation within 4 months

.

Although most new hawkweed infestations are probably started by seeds, expansi on of established populations is mostly vegetative. Thomas and7 Dale (1974) found that only 1 percent of new plants in a H. floribundum population were derived from seedlings. Studies in eastern Canada showed that seeds are not carried far by the wind; al though minute barbs along ribs on the seeds enable them to stick to hair, fur, feathers, clothing,

and vehicles

, and can be carried long distances.



### B . Areas A ffected by H awkweeds

In their native ranges, hawkweeds occur in the northern, central, and

eas tern portions of Europe as ruderal species ( plant s that grows in rubbish, poor land, or waste) of pastures, roadside cutbanks, abandoned fields, and meadows (Skalinska

, 1976). In most cases they are found in small, isolated pockets. Their highest densitie s are found on recently disturbed areas and they do not persist as dominant members of the early successional community (Skalinska

, 19 76 ). From Europe, hawkweeds spread to North America , New Zealand, Australia, Chile, and Argentina.

In North America, i nvasive hawkweeds are prim arily weeds of moist

pastures

, forest meadows, and mesic (moderately moist) rangeland. Based on current infestations, habitats most susceptible to invasion range from the lowlands of the northern Pacific Coast to elevations of 5, 000 feet or

more in the M ountain S tates (Littlefiel d et al.

, 20 08)

. Sites most vulnerable to invasion include roadsides, mountain meadows, clearings in forest zones, permanent pastures, hayfields, cleared timber units, and

abandoned farmland where the soi l is well drained, coarse textured, and moderately low in organic matter. Consequently, elk habitat, recreation areas, and pristine mountain meadows in areas that have a climate similar to that in their native range are particularly susceptible. Although introduced hawkweeds can grow in open woodlands, they do not tolerate shade very well. Across the United States and Canada, introduced hawkweeds are closely associated with habitats that can support oxeye daisy ( Chrysanthemum leucanthemum ), sulfur cinque foil ( Potentilla

recta ), spotted knapweed ( Cen t aurea maculosa ), gray goldenrod ( Solidago

nemoralis ), wild carrot ( Daucus carrota ), dandelion ( Taraxacum officinale ), and Kentucky bluegrass ( Poa pratensis ) (Thomas and Dale,
1974; Maycock and Guzikowa

, 1984)

. None of the introduced hawkweed species are found in the natural grasslands or shrub

- steppe of the northern Intermountain West, and are not expected to become problem weeds in any dry habitat usually associated with western rangelands. Neither

meadow n or orange hawkweed appears to survive in annually tilled cropland

.

There are many species of non

- native, invasive hawkweeds in North

America. These species originated from Europe, which is the native range to a massive complex of species, subspecies, a nd varieties of Hieracium

. Invasive hawkweeds were probably introduced into the eastern U nited

States and Canada during the 19th century. Two important subgenera 1. Native and

Introduced

R ange of

Hawkweeds

2. Known and
Potential

D istribution of

Hawkweeds in

North America8 distinguish the group of invasive species, subgenera Pilosella and

Hieracium

. Species in the se subgenera vary widely, both morphologically and in their invasion history and species distribution. The majority of species belong to subgenus Pilosella , including the species considered as targets for A. subterminalis

. ( See f igure 1 for a proposed ph ylogeny (taxonomic grouping) of North American Hieracium species. )

Figure 1. Proposed taxonomic grouping of North American Hieracium species by

Gaskin and Wilson (2007).9 The present distributions of these exotic species in the United States and

C anada are provided in t able 1

.

Table 1 . Invasive, Nonnative Hieracium species, from subgenus Pilosella

,

in the United States and Canada (from Wilson et al.

, 2006).

Species Distribution

H. arvicola Nageli et Peter CAN : NB

H. aurantiacum L. CAN : AB, BC , NB, NL, NS, ON, PE, QC,

SK

USA : AK, AR, CA, CO, CT, FL, ID, IN, I A

, MA, MD, ME, MI, MN, MT, NC, NH, NJ, NY, OH, OR, PA, RI, SD, VA, VT, WA, WV, WI, WY

H. bauhini Schult CAN : BC

USA : CT, ID, MA, MN, NH, NY, VT, WA

H. brachiatum Bertol. ex DC. CAN : QC

USA : NY

H. caespitosum Dumort CAN: AB, BC, NB, NL, NS, ON, PE, QC

USA : CT, DE, GA, ID, IL, IN, KY, MA, MD, ME, MI, MN, MT, NC, NH, NJ, NY, OH, OR, PA, RI, SC, TN, VT, VA, WA, WV, WI

H. H. derubellum Gottschl. et Schuhw. [ H. atramentarium act.] CAN : QC

USA : MI, NY, WI

H. flagellare Willd. H. flagellare Willd. [incl. H. macrostolonum ] CAN : BC, NB, NL, NS, ON, PE, QC

USA : CT, ID, MA, ME, MI, NH, NY, PA, VA, VT

H. floribun dum Wimm. & Grab. CAN : BC, NB, NL, NS, ON, PE, QC

USA : CT, ID, MA, MD, ME, MN, MT, NH, NJ, NY, OH, OR, RI, VA, VT, WA, WV

H. fuscoatrum Nageli & Peter USA : CT, NY, RI

H. glomeratum Froel. CAN : BC, ID, WA

H. lactuella Wallr. CAN : NS

H. pilosella L

. CAN : BC, NB, NL, NS, ON, PE, QC, Saint Pierre and Miquelon

USA : CT, DE, GA, MA, MD, ME, MI, MN, NC, NH, NJ, NY, OH, OR, PA, RI, TN, VA, VT, WA, WV

H. piloselliflorum Nageli et Peter [incl. H. apatelium ] CAN : NB, NL, NS, ON, PE, QC

H. piloselloid

es Vill. [incl. H. preaaltum ] CAN: BC, NB, NL, NS, ON, PE, QC

USA: CT, DE, GA, IL, IN, IA, MA, ME, MI, MN, MT, NC, NH, NY, OH, PA, RI, SC, VA, VT, WI, WV

H. stoloniflorum Waldst. e t Kit. CAN : QC10 Hieracium aurantiacum (orange hawkweed) was introdu ced into Vermont in 1875 as an ornamental and within 25 years spread throughout much of northeastern United States and southeastern Canada (Voss and Böhlke

, 1978). Within 25 years it had spread throughout much of New England, west to Michigan (Voss and Bö hlke

, 1978) and into Canada from New Brunswick to Ontario (Britton and Brown

, 1970). It now occurs throughout the eastern seaboard and into the Midwest, extending west to Minnesota and Iowa, and south to Virginia and North Carolina (Johnson

and Thomas

, 19 7 8 ). First recorded in Spokane, Washington, in 1945 (Marion Ownbey Herbarium, Wash. State Univ.), H. aurantiacum has been collected from gardens in Nevada County, California (Munz and

Keck

, 1959), on the east slope of the Rocky Mountains in Colorado (Webe r
, 1990), from coastal Oregon and Washington (Rickett

, 1973), and in southwestern British Columbia (Guppy

, 1976). In the western United States, populations of orange hawkweed were first reported from coastal Washington and Oregon (Peck , 1941; Abrams and F erris

, 1960). It has also been reported from the l ower m ainland of British Columbia (Guppy

, 1976) where it infests pastures, old fields, and roadsides. H. aurantiacum is now also recorded in Idaho, Montana, and Wyoming (USDA

– NRCS

, 200 8 ). It is more wide spread than other hawkweed species primarily because it is planted as an ornamental and often escapes cultivation.

Hieracium pilosella (mouse ear hawkweed) is widespread in the eastern

U nited States and Canada. In the west, it occurs in western Washing ton, western Oregon, Alaska, and British Columbia.

Hieracium flagellare (whiplash hawkweed) occurs primarily in the

northeastern U nited States and eastern Canada, but also occurs in British

C olumbia and Wyoming.

Hieracium floribundum (king devil hawkwe ed) w as first reported in northern New York in 1879 (Voss and Böhlke

, 1978) and 1900 respectively (Kennedy 1902). Recently, infestations of H. floribundum have been reported in western Washington (WSNWCB

, 1997), Northern Idaho (L. Wilson, unpubl. data.), a nd Montana (USDA

– NRCS

, 200 8 )

, and is reportedly expanding in range.

Hieracium piloselloides has been recorded in the western S tates of Montana and Washington (USDA

– NRCS

, 200 8 )

, and is also reportedly expanding in range. Suspected hybridization between H. caespitosum

, H. floribundum

, and H. piloselloides

, and the potential threat of these species in western habitats is the rationale for including these species as target weeds in the biological control program.

Hieracium caespitosum (meadow hawkweed) was l ikely introduced into the United States in 1828 (Britton and Brown

, 1970), and is now commonly found from Québec and Ontario (Frankton and Mulligan

, 1970)11 southward to Georgia and Tennessee (Rickett

, 1973). The first record of H. caespitosum in the wester n United States was in Pend Oreille County, Washington, in 1969 (Marion Ownbey Herbarium, Wash. State Univ.). H

. caespitosum is now recorded in the western S tates of Idaho, Montana, Oregon, Washington, and Wyoming, and is widespread throughout most of

sou thern British Colu mbia and Alberta.



### C

. Plants R elated to I nvasive H awkweeds and T heir

D istribution

Plants related t axonomically to invasive hawkweeds would be the most likely to be attacked by the proposed biological control organism A.

subterminalis. Plants related to the target hawkweeds are discussed below.

There are many species of Hieracium native to North America (Wilson

et al.

, 1 997). Distribution of native Hieracium species ranges from the east coast to west coast, from sea level to over 9

, 0 00 ft. in elevation, and

from northern to southern latitudes. As with the European hawkweeds , the number of native species has long been disputed. In order to understand species relationships in Hieracium , a brief outline of the generic divisions is prov ided.

There are generally considered to be about 36 species of Hieracium belonging to the three subgenera in America north of Mexico (Strother

, 2006 )

. A review of the regional flora revealed that about 25 species are

native to the United States and Can ada and fall into two subgenera:

Hieracium (3 species) and Chionoracium (22 species). Subgenus

Hieracium occurs chiefly throughout the boreal regions of North America

and Eurasia

, and is represented in North America by H. umbellatum L., H.

robinsonii Zahn , and H. canadense Michx. (considered part of

Chionoracium by Gaskin and Wilson

, 2007).

Subgenus Chionoracium is restricted to the New World and contains most

of our native taxa. Conflicting characters used to distinguish species have generated conside rable debate regarding classification. For example, Guppy (1978) suggested that H. scouleri Hook., H. albertinum Farr., and H. cynoglossoides L. are too closely correlated in characters to be distinguished into separate species and

, instead

, form a comple x of species. Guppy (1978) also suggested that H. umbellatum L. and its close relative, H. canadense Michx., may be two forms of the same species. Deardorff (1977) added H. longiberbe Howell and H. nudicale Heller to

the H. scouleri complex. Kartesz and Meacham (1999) provided a comprehensive synthesis of Hieracium spp. in America north of Mexico in which they list 108 species, subspecies

, and hybrids, clearly giving evidence of the myriad of described taxa in the genus.12 Ten additional hawkweed species found in the United States and Canada

are introduced from Eur ope and belong to two subgenera. Four species belong to the subgenus Hieracium : H. argillaceum Jordan group, H. groenlandicum Arv.

- Touv., H. lachenalii K.C. Gmel., H. murorum L., and

H. sabaudum L. Plants in this subgenus, except for H. lachenalii

, have not become weedy in North America. The remaining six species belong to the subgenus Pilosella and include the species targeted for biological control by A. subterminalis

.

S pecies that were used in testing the specificity of A. subterminal i s to
hawkweeds are lis te d in a ppendix 1

.



## I V

. Environmental Consequences

A. No A ction

Most invasive hawkweeds are perennial, creeping stoloniferous plants that can crowd out competing vegetation. They are not drought tolerant and cannot withstand prolonged periods of drying. However, they are very cold tolerant and easily persist at higher elevation, making the upland habitats through the Rocky Mountains and oth er western mo untain ranges susceptible to in vasion. In northern Idaho and British Columbia, habitats are open ponderosa pine and interior cedar

- hemlock. The re are no known medicinal or herbal uses for the invasive hawkweeds, nor do they have any

known social or recreational uses.

I nvasive hawkw eeds do affect threatened, endangered, and sensitive species because of their ability to form dense monocultures. One such example is encroachment by mouse

- ear hawkweed of habitat occupied by the threatened golden paintbrush, Castilleja levisecta , in Thur ston County, Washington (USFWS

, 1997). These monocultures compete for soil moisture and nutrients, thereby posing risks to indigenous species. As hawkweed monocultures invade species

- rich range and mountain habitats, ecosystem functions and ecological re lationships are affected. No known studies specifically address the effects of hawkweed on nutrient cycling and disturbance regimes ; however, hawkweed’s ability to dominate a community suggests that these species do affect habitat function. Hawkweeds gen erally negatively impact plant and animal diversity

, and there is serious concern about the loss of native plant biodiversity in

infested areas. Ecological losses in plant and animal diversity can be enormous but cannot be economically calculated. Additi onal expenditures

result from control costs. Hawkweeds are tenacious invaders and

, once established, quickly develop into a patch that continues to expand until it

covers the site with a solid mat of rosettes. Forage species in pastures and

abandoned far mland are choked out by the advancing front of hawkweed.

Hawkweeds also t hreaten lawns and gardens. Hawkweeds have been 1. Impact of
S pr ead of

Invasive

Hawkweeds13 reported to have allelopathic effects ( inhibition of growth in one species of plants by chemicals produced by another species ) on neig hboring vegetation (Dawes and Maravolo , 1973; Makepeace

, 1976).

Meadow hawkweed causes severe allergenic reactions. Reactions in people closely working with meadow hawkweed include minor skin rashes, sneezing, congestion, and difficulty in breathing

. Si milar effects have not been reported in animals. It is not known what portion of the plant causes this allergenic reaction

, although latex and other chemicals of closely related Asteraceae plants can cause dermatitis (Dawe s et al.

, 19 96).

Invasive hawk weeds have not been placed on the Federal Noxious Weed List but have been listed as noxious in Idaho, Montana, Washington, and

British Columbia. Regulations vary by S tate/ P rovince but generally involve actions such as restricted importation and/or quarant ine and prevention, containment, eradication

, or other control measures.

The continue d use of chemical herbicides, and mechanical and biological

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

chosen. These environmental c onsequences may occur even with the implementation of the biological control alternative, depending on the efficacy of A. subterminalis to reduce invasive hawkweed populations in

the C ontinental United States.

a. Chemical C ontrol

The use of herbicides , while effective, is limited to relatively accessible sites and control is only temporary. Broadcast applications of herbicides could have adverse impacts on nontarget vegetation if not carefully applied

.

b. Mechanical C ontrol

Disturbance of hawkwee ds by machinery spreads the weeds across the

field. Local disturbances caused by grazing livestock, ungulates, and rodents also enhance the rate of spread of hawkweed. In lawns, mowing

does not kill invasive hawkweeds because the low lying stolons and

rh izomes are missed by the mower blades. Although mowing prevents seed production by removing flowering stems, repeated mowing encourages faster vegetative spread.

c. Biological C ontrol

No organisms for the biological control of hawkweeds have been rel eased

in North America. Gall formation by A. subterminalis diverts plant nutrients from the normal growth of other plant tissues. Under certain 2. Impact from

U se of O ther
C ontrol

M ethods14 conditions

, galls may stress the plant, reducing competitive ability, seed production, and long distance sprea d of the weed.



### B. Issue P ermit s for E nvironmental R elease of A.
subterminalis

Host specificity of A. subterminalis to the invasive hawkweeds Hieracium pilosella, H. aurantiacum, H. floribundum, and H. flagellare has been demonstrated through scientific literature, 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 contro l organism proposed for environmental release.

a. Scientific L iterature

In previous literature, A. subterminalis has only been reported to induce galls on H. pilosella and has not been recorded from any other species (Syret t et al., 1 998).

b. Field O b servations

In the field, A. subterminalis has not been observed or reported on any species other than H. pilosella (Syre tt et al., 19 98).

c. Host S pecificity T esting

Host specificity tests a re test s to determin e how many plant species A.

subtermina lis attacks/eats, and whether nontarget species may be at risk

. In host specificity te sting (Syrett et al., 1998; 2001; Grosskopf et al., 2001,

Littlefield et al., 20 08 )

, gall formation by A. subterminals only occurred on invasive hawkweed species targete d for biological control. No native hawkweeds or plant species of closely related genera were attacked

.

(1) Site of Q uarantine and F ield S tudies

Laboratory tests were conducted at the CABI

- Europe Station in Delémont, Switzerland, at the insect contai nment facility located at the Canterbury Agriculture and Science Centre, Lincoln, New Zealand, and in quarantine

facilities at Montana State Universit y ( MSU ) , Bozema n, Montana. Open

field releases began in 1999 in New Zealand.

(2) Test P lant L ist

The l ist of plant species used for host specificity testing of A.

subterminalis is shown in a ppendix 1. The strategy used for selecting 1. Impact of A.
subterminalis

on Nontarget

P lants15 plants for testing is based on the phylogenetic approach, where closely related species are theorized to be at greater risk of attack than are distantly related species (Wapshere, 1974)

.

The initial host specificity testing of A. subterminalis was conducted for the field release of the wasp in New Zealand. Plants utilized for testing were selected from the following categor ies (Syret t et al.

, 1 998):

• representatives of the plant family Asteraceae (the family to which hawkweeds belong) ;

• plant species on which the gall wasp has been recorded in the field;

• cultivated plant species and representatives of New Zealand na tive plant species (various non

- Asteraceae families) that have not previously been exposed to the wasp; and

• plant species that are hosts of close relatives of A. subterminalis

, that is, hosts of other species of Aulacidea

.

Host specificity testing at the CABI

- Europe Station, Delémont

, and at the Canterbury Agriculture and Science Centre, Lincoln, New Zealand

, consisted of eight species within the genus Hieracium , including five from the subgenus Pilosella and three from the subgenus Hieracium

. Thirtee n additional species from the tribe Lactuceae were tested, including native New Zealand plant species that would not previously have been encountered by the wasp ( Knightia excelsa

, Raoulia hookeri , Kirkianella

novae

- zelandiae

, Celmisia lyalli

, Helichrysum bellidioides

, Gaultheria depressa , and Discaria toumatou ). A further 11 species within the family Asteraceae were tested, including economically significant cultivated plant species. Species from 21 other families containing important cultivated

and nati ve plants were also included, making a total test plant list of

48 species.

Plants for testing the host range of A. subterminalis were selected from seven possible categories. Test categories consisted of the following:

CATEGORY 1: Genetic types of Hie racium (varieties, races, forms,

genotypes, apomicts, etc.).

CATEGORY 2: North American species in the same genus as Hieracium

,

divided by subgenera, including economically and environmentally important plants.

CATEGORY 3: North American species in oth er genera in the Asteraceae

family, divided by subtribe, tribe, and subfamily, including economically and environmentally important plants.16 CATEGORY 4: Threatened and endangered species in the Asteraceae

family, divided by subgenus, genus, subfamily, and tribe.

CATEGORY 5: North American species in other families in the Asterales

order that have some phylogenetic, morphological, or biochemical relationship to the target weed, including economically and environmentally important plants.

CATEGORY 6: Nor th American species in other orders that have some

morphological or biochemical relationship to the target weed, including economically and environmentally important plants.

CATEGORY 7: Any plant on which the biological control agent or its

close relativ es (within the same genus) have been previously recorded to feed and/or reproduce.

( See a ppendix 2 for a more detailed description of plants selected in each

category. )

Host specificity testing of A. subterminalis at MSU and CABI

- Europe included as many native North American representatives of the various taxa as possible

. Aulacidea subterminalis was tested on 65 plant species of which 35 are species native to North America ( a ppendix 1 )

.

(3) Discussion of Host Specificity Testing

New Zealand Tests

—

I n overseas testing, Syre tt et al. (1998 and 2001) and Grosskopf et al. (20 01) reported gall formation on H. pilosella and H.

aurantiacum but n ot on other tested plant species , while Grosskopf and Senhadji Navarro (2004) reported gall formation on H. pilose lla but not on

H. aurantiacum or other teste d plant species.

North American Tests

— During the North American host specificity test, galls were only induced on four exotic species: H. pilosella (its native host), H. aurantiacum, H. flagellare, and H. flori b undum ( a ppendix 4)

. No native or other test plants were infested

.

( See a ppendices 3 and 4 for host specificity study results. )

To assess the impact of A. subterminalis on H. pilosella in New Zealand, an experiment was set up to examine the effect of the gall wasp on plant growth under stress

- free conditions in a shade house trial with potted plants (Klöppe l et al., 2003 ). Plants with galls showed a reduction in stolon length of 75 percent

. They had slightly lower total dry matter and

reduced root we ight. In a glasshouse experiment

, the impact of water stress, nutrient stress, and plant competition on growth of H. pilosella and 2. Impact of A.
subterminalis

on Hawkweeds17 performance of the gall wasp were measured. The number and mean diameter of gall clusters were not significantly different between treatment and control plants

. However, galled plants produced more, but shorter,

stolons in all stress treatments and stolons that were more branched in

nutrient

- and water

- stressed plants, than ungalled plants

. Galling by A.

subterminalis is lik ely to reduce vegetative reproduction of H. pilosella whether or not plants are stressed, indicating that the wasp may be a successful biocontrol agent (Klöppel et al.

, 20 03).

Researchers expect that A. subterminalis will be able to build up substantial p opulations in North America and

, thereby

, reduce above

ground biomass and seed output of established invasive hawkweed patches (Littlefiel d et al., 20 08)

. It is difficult to predict the long

- term impact on invasive hawkweed infestations; however, reductio ns in the above

- ground growth rate and seed output may lead to reduced competitive ability of the weed and reduced patch expansion and long

- distance dispersal of invasive

hawkweed seeds and establishment of new infestations (Littlefield et al.,

20 08).

On ce a biological control agent such as A. subterminalis is released into

the environment and become s established, there is a slight possibility th at
it could move from the target plant s ( invasive hawkweeds ) to attack

nontarget plants

. H ost shifts by introd uced 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 (Loud a et al., 2003 )

. If other plant species were to be attacked by A.

su bterminalis , the resulting effects could be environmental impacts that may not be easily reversed. Biological control agents such as A.

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

hosts occur

, and in which the climate is suitable for reproduction and

survival.

In addition, th is agent may not be successful in reducing hawkweed

p op ulations in the continental United States. Worldwide, biological weed control programs have had an overall success rate of 33 percent; success rates have been considerably higher for p rograms in individual countries (Culliney, 2005)

. Actual impacts on hawkweeds by A. subterminalis will not be known until after release occurs and post

- releas e monitoring has been conducted. It is expected that A. subterminalis will reduce invasive

hawkweed populations by reduc ing above

- ground biomass and seed output

of e stablished invasive hawkweed patches

.

A. subterminalis is a wasp but it does not sting or produce venom. It is a plant

- feeding wasp which poses no risk to humans or other animals

. 3. Uncertainties

R egarding the

E nviron

mental

R elease of A.

subterminalis

4 . Human H ealth18 ―Cumulative impacts are defined as the impact on the environment whic h results from the incremental impact of the action when added 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 hawkweeds

, as well as other invasive weeds

. Chemical and mechanical methods, as described previously in this

document

, are u sed in a wide range of habitats. Some of these control

programs in Idaho, Washingt on, Montana, Oregon, and Alaska are listed

below.

Idaho

— Idaho Department of Lands Kootenai County Weed Board Palouse Clearwater Cooperative Weed Management Area Panhandle Lakes Cooperative Weed Management Area Potlach Corporation

U

. S

. D epartment of Interior (USDI), Bureau of Land Management Rimrock Hawkweed Cooperative Selkirk Cooperative Weed Management Area Benewah County Weed Board Pend Oreille County Weed Board

Washington

— Washington State Weed Board Stevens County Weed Board King County Weed Board

Montana

— Gallatin National Forest

Lolo National Forest

Bitterroot National Forest

Flathead National Forest

Kootenai National Forest

Glacier National Park

U.S. F ish and Wildlife Service

– Lost Trail Refuge

USDI

, Bureau of Land Management

Lincol n County Weed Department Flathead County Weed Department Flathead County Extension Ravalli County Weed Department Sanders County Extension Missoula County Weed Department Mineral County Weed Department Lake County Weed Department Glacier County Weed Depart ment 5. Cumulative Impacts19 Montana cont’d.

— Granite County Weed Department Powell County Weed Department Gallatin County Weed District

Judith Basin Weed District Big Sky Weed Management Area

M ontana Department of Agriculture

Montana Noxious Weed Trust Fund

Montana D epartment of N atural R esources and C onservation

Confederated Salish Kootenai Tribe Plum Creek Timber Company

Oregon

— Oregon Department of Agriculture Union County Weed Control Deschute County Weed Control Wallowa County Weed Control Asotin County Weed Control

East Multnomah Soil and Water Conservation District

Wallowa Whitman National Forest

Alaska

— Kodiak National Wildlife Refuge

Homer Soil and Water Conservation District

Kodiak Garden Club Koniag Native Corporation University of Alaska Fairbanks Cooperative Exte nsion Service Upper Susitna Soil and Water Conservation District

Juneau Invasive Plants Action

Release of A. subterminalis is not expected to have any negative cumulative impacts in the continental United States because of its host specificity to invasive hawkweeds

. Effective biological control of invasive

hawkweeds will have beneficial effects for weed management programs
, and may result in a long

- term, non

- damaging method to assist in the

control of hawkweeds

.

Section 7 of the Endangered Species A ct ( 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 threatened

and endangered species or result in the destruction or adverse modification

of critical habitat.

T he adverse effects of hawkweed invasion on threatened and endangered species is not fully known ; however, it can be assumed that invasive hawkweeds do affect threatened, endangered, and sensitive species because of their ability to f orm dense monocultures. One such example is 6. Endangered Species Act20 encroachment by mouse

- ear hawkweed into habitat occupied by the threatened golden paintbrush, Castilleja levisecta , in Thurston County, Washington (USFWS

, 1997). These hawkweed monocultures compete for

soil moi sture and nutrients, thereby posing risks to native plant species. As hawkweed monocultures invade species

- rich range and mountain habitats, it is thought that ecosystem functions and ecological relationships

are affected (Littlefiel d et al., 200 8)

.

Ho st specificity has been demonstrated by A. subterminalis . Fro m the literature, field observations, and host specificity testing, it has been

de termined that A. subterminalis is specific to species in the genus

Hieracium , subgenus Pilosella (Littlefi eld et al., 2008). Ther e are no
Hieracium species federally listed as threatened or endangered. No federally listed animal species are known to use invasive hawkweeds.

For these reasons , APHIS has determined that environmental release of A.

subterminalis wi ll have no effect , or a potentially beneficial effect

, depending on the efficacy of the organism, on threatened and endangered species.



## V . Other Issues

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

Environ mental Justice in Minority Populations and Low

- income Populations,‖ APHIS considered the potential for disproportionately high and adverse human health or environmental effects on any minority populations a nd low

- income populations. There are no adverse

e nvironmental or human health effects from the field release of A.

subterminalis and will not have disproportionate adverse effects to any minority or low

- income populations.

Consistent with EO 13045, ―Protection of Children From Environmental

Health Ris ks 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 a nticipated as a consequence of the field release of A.

subterminalis

.

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 Federal policies that have tribal implications....‖21 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 accordance with

EO 13175

.22



## VI. Agencies, Organizations, and
Individuals Consulted

The Technical Advisory Group for the Biological Control Agents of Weeds (TAG) recommended the release of A. subterminalis on August 10

, 2009

. TAG members that reviewed the release petition ( Littlefiel d et al.,

2008 ) included representatives from APHIS, Cooperative Sta te Research, Education, and Extension Service, Forest Service, Environmental Protection Agency, U.S. Army Corps of Engineers, the National Plant Board, and representatives from Canada

.

This EA was prepared and reviewed by APHIS. The addresses of partici pating 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 Riverdale, 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

Montana State University Department of Land resources and Environmental Sciences

P.O. Box 173120 Bozeman, MT 59717

– 302023



## V II . References

Abrams, L.

, and Ferris , R.S., 1960. Illustrated f lora of the Pacific States, Vol. IV, Bignoniaceae to Compositae. Stanford Univ. Press, CA.

Aspinall, J.

, 2006. Rearing and release of five insect speci es for biological

control of five Hieracium species. Final Report, Hieracium Control Trust, MAF Sustainable Farming Fund Project Summary.

Bremer, K.

, 1994. Asteraceae: c ladistics and c lassification. Timber Press, Portland, OR.

Britton, N.L.

, and Brow n , H.A., 1970. An i llustrated f lora of the Northern United States and Canada, Second Edition, Vol. I

- III. New York: Dover

Publications Inc.

Buchanan, R.A., Cull, I.M., Otey

, F.H., and Russell , C.R., 1978. Hydrocarbon

- and rubber

- produc ing crops: Evalu ation of 100 U. S. plant species. Econ onmic Bot any

. 32: 146

− 153.

Callihan, R.H., Wilson, L.M., McCaffrey, J.P., and Miller , T.W., 1997

Hawkweeds Hieracium aurantiacum, H. pilosella, H. pretense, H. floribundum, H. piloselloides. PNW 499 http://info .ag.uidaho.edu/pdf/PNW/PNW0499.pdf last accessed October
14, 2009.

Culliney, T.W.

, 2005. Benefits of classical biological control for managing invasive plants. Critical Reviews in Plant Sciences. 24:

131

− 150.

Dawes, D.S.

, and Maravolo , N.C., 1973. Isolation and characteristics of a possible allelopathic factor supporting the dominant role of Hieracium

aurantiacum in the bracken grasslands of northern Wisconsin. Wisconsin

Acad emy of Sciences, Arts, and Letters

. 61: 235

− 252.

Dawes, R.S., Green, C .M., MacLeod

, T.M., and Ferguson , J

. , 1996. Daisy, dandelion and thistle contact allergy in the photosensitivity dermatitis and actinic reticuloid syndrome. Contact dermatitis

. 35:

109

− 110.

Deardorff, D.C.

, 1977. Biosystematic studies in Hieracium (As teraceae), section Thrysoidea. Ph.D. Thesis, University of Washington, Seattle.

Ellenberg, H.

, 1988. Vegetation e cology of Central Europe. Cambridge Univ. Press, Cambridge, UK.24 Fauna Europaea

, 2007. Fauna Europaea Version 1.1, www.faunaeur.org

last accessed September 30, 2009.

Frankton, C., and Mulligan , G.A., 1970. Weeds of Canada. Publication

948. Ottawa: Canada Department of Agriculture

.

Flora of North America Editorial Committee, eds. Flora of North Am erica

North of Mexico. 12+ vols. New York a nd Oxford

. http://www.efloras.org last accessed September 30, 2009

.

Gaskin, J.F.

, and Wilson , L.M., 2007. Phylogenetic r elationships a mong

n ative and n aturalized Hierac ium (Asteraceae) in Canada and the United

States b ased on p lastid DNA s equences. Systematic Botany

. 32:

478

− 485.

Grosskopf, G., Butler, S., Recher, H., and Schneider , H., 2001. Biological control of hawkweeds, Hieracium spp. Ann ual Rep ort , CABI Bioscience Switzerland Centre, Delémont, Switzerland. 36 p.

Grosskopf, G. and Senhadji Navarro , K., 2004. Biolog ical control of hawkweeds, Hieracium spp. Ann ual Rep ort , CABI Bioscience Switzerland Centre, Delémont, Switzerland. 34 p.

Guppy, G.A.

, 1976. The hawkweeds ( Hieracium ) of British Columbia.

Davidsonia

. 7(2): 13

− 17.

Guppy, G.A.

, 1978. Species relations hips of Hieracium (Asteraceae) in

British Columbia. Can adian Journal of Botany

. 56(23): 3008

− 3019.

Hay, J.R.

, and Ouellette , G.J., 1959. The role of fertilizer and 2,4

- D in the control of pasture weeds. Canadian Journal of Plant Science. 39 : 78

− 283.

Johnson, C.D.

, and Thomas , A.G., 1978. Recruitment and survival of seedlings of a perennial Hieracium species in a patchy environment.

Can adian Journal of Botany

. 56 : 572

− 580.

Kartesz, J.T., and Kartesz , R., 1980. A s ynonymized c hecklist of the

v ascu lar f lora of the United States, Canada, and Greenland

- Vol. II: The Biota of North America. Univ. of North Carolina Press, Chapel Hill, NC.

Kartesz, J.T. and Meacham , C.A., 1999. Synthesis of the North American flora, Version 1.0. North Carolina Botani cal Garden, Chapel Hill, N C

. Klöppel, M., Smith, L., and Syrett , P., 2003. Predicting the impact of the biological control agent Aulacidea subterminalis (Cynipid ae) on growth of Hieracium pilosella (Asteraceae) under differing environmental conditions

in New Zealand. Biocontrol Sci ence and Tech nology

. 13: 207

− 218.25 Krahulec, F. A.

, Krahulcova, J., Fehrer, S., Bräutigam, S., and Schuhwerk

, F., 2008. The structure of the agmic complex of Hieracium subgen.

Pilosella in Šumava Mts. and it comparision with ot her regions in Central Europe. Prelia

. 80:1

− 26.

Lass, L.W.

, and Callihan , R.H., 1992. Response of yellow hawkweed to range herbicides in a non

- crop site. Res. Prog. Rep. West. Soc. Weed Sci.

45: 20

− 21.

Littlefield, J., Grosskopf, G., and Wilson , L., 2008. A p etition for the f ield

r elease of the g all w asp Aulacidea subterminalis (Hymenoptera: Cynipidae) for b iological c ontrol of i nvasive h awkweeds in North America (Petition 09

- 02). Submitted to the Technical Advisory Group for Biological Control Agen ts of Weeds. December 2008. 77 pp.

Loomis, E.S.

, 2007. Sex and diversity in the invasive plant Hieracium

aurantiacum

. MS Thesis, University of Montana. 54 pp.

Louda, S.M., Pemberton, R.W., Johnson, M.T., and Follett , P.A., 2003.

N ontarget effects−The Achilles’ h eel of biological control? Retrospective analyses to reduce risk associated with biological control introductions. Annual Review of Entomology. 48: 365

– 396.

Mabry, T.J., and Bohlmann , F., 1977. Summary of the chemistry of the

c ompositae. In : The Biology and Chemistry of the Compositae, Vol. II. V. H. Heywood, J. B. Harborne, and B. L. Turner, [ e ds .] , pp. 1097

− 1104. Academic Press, New York, NY.

Makepeace, W.

, 1976. Allelopathy of mouse

- ear hawkweed. Proceedings

of t he 29th New Z ealand Weed and Pest Conference. 106

− 109.

Mañez, S., Recio, M.C., Giner, R.M., Sanz, M.J., Terencio, M.C., Peris,
J.B., Stübing

, G., and Rios , J.

- L., 1994. A chemotaxonomic review of the subtribe Crepidinae based on its phenolic constituent s. Biochem. Syst.

Evol. 22(3): 297

− 305.

Maycock, P.F.

, and Guzikowa , M., 1984. Flora and vegetation of an old field community at Erindale, southern Ontario. Canadian Journal of Botany. 62: 2193

− 2207.

Metcalfe, C.R.

, 1967. Distribution of latex in t he plant kingdom. Economic Botany

. 21: 115

− 127. Miller, T.W., Shinn, S.L., and Thill , D.C., 1998. Response of yellow

hawkweed to several herbicides. Western Society of Weed Science. 1998 Research Progress Report ISSN

– 0090

– 8142. p. 8.26 Munz, P.A.

, and Keck , D.D., 1959. A California f lora. Univ. of California Press, Berkeley, CA.

Noel, W.O., Belles, W.S., Wattenbarger, D.W., and Lee , G.A., 1979. Chemical control of orange hawkweed on rangeland. Proc. West. Soc.

Weed Sci. 32: 77.

Panebianco, R. and Willemsen , R.W., 1976. Seed Germination of Hieracium pratense , a Successional Perennial. Bot. Gazette

. 137(3):

255

− 261.

Peck, M.E.

, 1941. A manual of the higher plants of Oregon. Binfords and Mort, Portland, O R

. 866 pp.

Pemberton, R.W.

, 2000. Predictable risk to native plants in weed biological control. Oecologia. 125: 489

– 494.

Peterson, R.L.

, 1979. Root buds in Hieracium florentinum : Effects of nitrogen and observations on bud growth. Bot. Gazette

. 140: 407

− 413.

Reader, R.J.

, 1990. Competition constrained by low nutrient supply: an example involving Hieracium floribundum Wimm and Grab. (Compositae). Func tional Ecology

. 1990(4): 573

− 577.

Reader, R.J.

, and Watt , W.H., 1981. Response of hawkweed ( Hieracium floribundum ) patches to NPK fertilizer in an abandoned pasture. Can adian

Journal of Bot any

. 59: 1944

− 1949.

Rickett, H.W.

, 1973. Wildflowers of the United States, Vols I

– VI. New

York Botanical Garden.

Scott, D., Robertson, J.S., and Archie , W.J., 1990. Plant d ynamics of New

Zealand t ussock g rassland i nfested with Hieracium pilosella . I. Effects of

s easonal g razing, f

ertilizer and o verdrilling. Jour nal of Applied Ecology

. 27(1): 224

− 234.

Skalinska, M.

, 1976. Cytological diversity in the progeny of octoploid facultative apomicts of Hieracium aurantiacum . Acta. Biol. Cracov. Ser.

Bot. 19(1): 39

− 46.

Smith, L., Syrett, P., and Grosskopf , G., 2007. Midge and wasp gain

tarsus hold

– successful release strategies for two biocontrol agents for

hawkwe ed. (Poster). www.MAF.govt.NZ/sff/about

- projects/search/06

- 052/poste r

- biocontrol

- agents

- for

- hawkweed

- 06

- 052.pdf last accessed Sept em ber 30, 2009

.27 Sorensen, N.A.

, 1977. Polyacetylenes and conservatism of chemical characters in the Compositae. In : V. H. Heywood, J.B. Harborne, and B.L.

Turner [ eds ]

. The Biology and Chem istry of the Compositae, Vol. I., pp.

385

− 409. Academic Press, New York, NY.

Stergios, B.G.

, 1976. Achene production, dispersal, seed germination, and seedling establishment of Hieracium aurantiacum in an abandoned field community. Can adian Journal of B ot any

. 54: 1189

– 1197.

Strother , J.L.

, 2006. Hieraciu m

. In : Flora of N orth America North of

Mexico. vols. 19

– 21 (Flora of North America Editorial Committee, Eds.), pp. 278

– 294. New York: Oxford University Press.

Syrett, P., Smith, L.A., and Grosskopf , G., 1998. Introduction of

Aulacidea subterminalis (Hymenoptera: Cynipidae) into New Zealand for

b iological c ontrol of Hieracium pilosella

. Manaaki Whenua Landcare Research Contract Rep. LC9798/80, Lincoln, New Zealand.

Syrett, P., Smith, L.A., Grossko pf, G., and Muerk , C., 2001. Predic ting the likely success of biological control of hawkweeds in New Zealand. Plant Protection Quarterly

. 16: 172

− 176.

Thomas, A.G. and Dale , H.M., 1974. Zonation and regulation of old pasture populations of Hieracium f loribundum

. Can adian Journal of

Bot any

. 52: 1451

− 1458.

Tomb, A.S.

, 1977. Lactuceae

- system atic review. In : The b iology and

c hemis try of the c ompositae, Vol. II. V.H. Heywood, J.B. Harborne, and
B.L. Turner, [ e ds ] , pp. 1067

− 1079. Academic Press, New Y ork, NY.

Trewick, S.A., Morgan

- Richards, M., and Chapman , H.M., 2004. Cholorplast DNA diversity of Hieracium pilosella (Asteraceae) introduced to New Zealand: reticulation, hybridization and invasion. American Journal of Botany

. 91(1): 73

– 85.

U

. S

. Dep artment of Agriculture, Natural Resource Conservation

Service

, 2008. The PLANTS Database http://plants.usda.gov last

accessed September 30, 2009

. National Plant Data Center, Baton Rouge, LA 70874

– 4490 USA.

USDA, NR CS ―S ee U

. S

. Department of Agriculture, Natural Resource

Conservation Service.

USFWS―S ee U

. S

. Fish and Wildlife Service28 U

. S

. F ish and W ildlife S ervice, 1993. Part IV: Plant t axa for l isting as

e ndangered or t h reatened s pecies; n otice of r eview, 50 CFR P art 17. Federal Register 58: 51144

– 51190.

U

. S

. F ish and W ildlife S ervice, 1996. Part III: Endangered and t hreatened

s pecies, p lant and a nimal t axa; p roposed r ule, 50 CFR Part 17. Federal Register

. 61: 7596

– 7613.

U

. S

. F ish and W ildlife S ervice, 1997. E ndange red and threatened wildlife and plants; determination of threatened status for Castilleja

levisecta (golden paintbrush). Federal Register

. June 11, 1997,

vol. 62:31740

- 31748.

Voss, E.G.

, and Böhlke , M.W., 1978. The status of certain hawkweeds ( Hi eracium subgenus Pilosella ) in Michigan. Mich. Bot. 17(2): 35

– 47.

Wapshere, A.J

. , 1974. A strategy for evaluating the safety of organisms for biological weed control

. Annals of Applied Biology

. 77: 201

– 211.

Wapshere, A. J.

, 1983. Problems in the use of plant biochemistry for establishing the safety of biological control agents for weeds: The

Chondrilla and Echium /

Heliotropium cases. Entomophaga

. 28 : 287

– 294.

Washington State Noxious Weed Control Board

, 1997. WSR 97

– 24

– 051

Permanent Rules Noxious W eed Control Board.

Weber, W.A.

, 1990. Colorado flora: e astern s lope. Univ. Press of Colorado, Niwot.

Wilson, L.M., Fehrer, J., Bräutigam, S., and Grosskopf , G., 200 6 . A new invasive hawkweed, Hieracium glomeratum (Lactuceae, Asteraceae), in

the Pacif ic Northwest. Can adian Journal of Bot any

. 84: 133

– 142.

Wilson, L

. M., McCaffrey, J.P., Quimby, Jr. , P.C., and Birdsall , J.L., 1997. Hawkweeds in the Northwestern United States. Rangelands

. 19(4): 18

– 23.

WSNWCB

― S ee Washington State Noxious Weed Control Board

.

Zomlefer, W.B.

, 1994. Guide to f lowering p lant f

amilies. Univ. of North Carolina Press, Chapel Hill, NC

.29

Appendix 1

. Plant species tested during A. subterminalis host specificity trials (excluding NZ tests). Asteraceae species are listed by family, subfamily, tribe, and subtribe with species listed alphabetically within tribes. Common names, S tate distributions, growth habits, durations, and U

. S

. nativities are from the USDA

– NRCS Plants Database (20 08) and Canadian from Flora of Nort h America North of Mexico (1993 ) ( f rom Littlefield et al., 2008).

Family Subfamily

Tribe
Subtribe Scientific Name Common Name U.S.

- State Distribution

Canada

- Province Distribution Growth
Habit Duration U

. S

. Nativity Test

Category 1

Asteraceae
Cichorioideae

Lactuceae

Microseridinae Agoseris glauca pale agoseris AK, AZ, CA, CO, IA, ID, MI, MN, MT, ND, NE, NM, NV, OR, SD, UT, WA, WY

AB, BC, MB, NT, ON, SK, YT Forb/herb
Shrub
Subshrub Perennial Native 3b

Asteraceae
Ci chorioideae

Lactuceae

Microseridinae Agoseris grandiflora bigflower agoseris CA, ID, MT, NV, OR, UT, WA

BC Forb/herb Perennial Native 3b

Asteraceae
Cichorioideae

Lactuceae
Catananchinae Catananche caerulea Cupid’s Dart Cultivated Forb/herb Perennial Cul tivated 3b
Ornamental

Asteraceae
Cichorioideae

Lactuceae unassigned Cichorium intybus chicory AL, AR, AZ, CA, CO, CT, DC, DE, FL, GA, IA, ID, IL, IN, KS, KY, LA, MA, MD, ME, MI, MN, MO, MS, MT, NC, ND, NE, NH, NJ, NM, NV, NY, OH, OK, OR, PA, RI, SC, SD, TN, TX, UT, VA, VT, WA, WI, WV, WY

AB, BC, MB, NB, NF, NS, ON, PE, PQ, SK Forb/herb Biennial

Perennial Introduced 3b

Economic

Asteraceae
Cichorioideae

Lactuceae Crepidinae Crepis atribarba slender

hawksbeard CO, ID, MT, NE, NV, OR, UT, WA, WY

AB, BC, SK Forb/herb Perennial Native 3b

Asteraceae
Cichorioideae

Lactuceae Crepidinae Crepis biennis hawksbeard MI, NY, OH, PA, VA, VT

NF Forb/herb Biennial

Perennial Introduced 3b

Asteraceae
Cichorioideae

Lactuceae

Hieraciinae Hieracium albiflorum white hawkwee d AK, CA, CO, ID, MT, NV, OR, SD, UT, WA, WI,

WY

AB, BC, NT, PQ, SK Forb/herb Perennial Native 2

Asteraceae Hieracium argutum southern CA Forb/herb Perennial Native 230

Family Subfamily

Tribe
Subtribe Scientific Name Common Name U.S.

- State Distribution

Canada

- Province Distribution Growth
Habit Duration U

. S

. Nativity Test

Category 1

Cichorioideae

Lactuceae

Hieraciinae hawkweed

Asteraceae
Cichorioideae

Lactuceae

Hier aciinae Hieracium aurantiacum orange hawkweed AK, AR, CA, CO, CT, FL, GA, IA, ID, IL, IN,

MA, MD, ME, MI, MN, MT, NC, NH, NJ, NY, OH, OR, PA, RI, SD, TN, VA, VA, VT, WA, WI, WV, WY

AB, BC, LB, MB, NB, NF, NS, ON, PE, PQ, SK Forb/herb Perennial Introduced 1

Asteraceae
Cichorioideae

Lactuceae

Hieraciinae Hieracium bolanderi Bolander’s

hawkweed CA, OR Forb/herb Perennial Native 2

Asteraceae
Cichorioideae

Lactuceae

Hieraciinae Hieracium caespitosum meadow

hawkweed CT, DC, GA, ID, IL, IN, KY, MA, MD, ME, MI,

MN, MT, NC, NH, NJ, NY, OH, OR, PA, RI, SC, TN, VA, VT, WA, WI, WV, WY

BC, MB, NB, NF, NS, ON, PE, PQ Forb/herb Perennial Introduced 1

Asteraceae
Cichorioideae

Lactuceae

Hieraciinae Hieracium canadense Canadian

hawkweed MI, ME

AB, BC, LB, MB, NB, NF , NS, NT, ON, PE, PQ, SK, YT Forb/herb Perennial Native 2

Asteraceae
Cichorioideae

Lactuceae

Hieraciinae Hieracium carneum Huachuca

hawkweed AZ, NM, TX Forb/herb Perennial Native 2

Asteraceae
Cichorioideae

Lactuceae

Hieraciinae Hieracium fendleri yel low hawkweed AZ, CO, NM, TX, VT, WY Forb/herb Perennial Native 2

Asteraceae
Cichorioideae

Lactuceae

Hieraciinae Hieracium flagellare large

mouseeared CT, DE, IN, MA, ME, MI, NJ, NH, NY, OH, PA,

VA, VT, WY

BC, NB, NS, PE, PQ Forb/herb Perennial Introduc ed 2

Asteraceae
Cichorioideae

Lactuceae

Hieraciinae Hieracium floribundum king devil CT, ID, MA, MD, ME, MI, MN, MT, NH, NJ, NY, OH, RI, VA, VT, WA, WV, WY

BC Forb/herb Perennial Introduced 131

Family Subfamily

Tribe
Subtribe Scientific Name Common Name U.S.

- State Distribution

Canada

- Province Distribution Growth
Habit Duration U

. S

. Nativity Test

Category 1

Asteraceae
Cichorioideae

Lactuceae

Hieraciinae Hieracium glom eratum queen

- devil WA, ID

BC Forb/herb Perennial Introduced 2

Asteraceae
Cichorioideae

Lactuceae

Hieraciinae Hieracium gracile slender

hawkweed AK, CA, CO, ID, MT, NM, OR, UT, WA, WY

AB, BC, NT, YT Forb/herb Perennial Native 2

Asteraceae
Cichorioideae

Lactuceae Hieracium greenei Greene’s

hawkweed CA, OR Forb/herb Perennial Native 2

Asteraceae
Cichorioideae

Lactuceae

Hieraciinae Hieracium gronovii queen devil AL, AR, CT, DC, DE, FL, GA, IL, IN, KS, KY, LA, MA, MD, ME, MI, MO, MS, NC, NJ, NY, OH, OK, PA , RI, SC, TN, TX, VA, WY

ON Forb/herb Perennial Native 2

Asteraceae
Cichorioideae

Lactuceae

Hieraciinae Hieracium horridum prickly hawkweed CA, NV, OR Forb/herb Perennial Native 2

Asteraceae
Cichorioideae

Lactuceae

Hieraciinae Hieracium longiberbe longb eard

hawkweed OR, WA Forb/herb Perennial Native 2

Asteraceae
Cichorioideae

Lactuceae

Hieraciinae Hieracium longipilum hairy hawkweed AR, IA, IL, IN, KS, KY, LA, MI, MN, MO, NE, OH, OK, TN, TX, WI

ON Forb/herb Perennial Native 2

Asteraceae
Cichorioideae

Lactuceae

Hieraciinae Hieracium parryi Scouler’s woollyweed CA, ID, MT, NV, OR, WA, WY Forb/herb Perennial Native 2

Asteraceae
Cichorioideae

Lactuceae

Hieraciinae Hieracium pilosella mouseear hawkweed CT, GA, MA, ME, MI, MN, NC, NH, NJ, NY,

OH, OR, PA, RI , TN, VA, VT, WA

BC, NB, NF, NS, ON, PQ Forb/herb Perennial Introduced 132

Family Subfamily

Tribe
Subtribe Scientific Name Common Name U.S.

- State Distribution

Canada

- Province Distribution Growth
Habit Duration U

. S

. Nativity Test

Category 1

Asteraceae
Cichorioideae

Lactuceae

Hieraciinae Hieracium piloselloides yellow devil

hawkweed CT, DE, GA, IA, IL, IN, MA, ME, MI, MN, MT,

NC, NH, NJ, NY, OH, PA, RI, VA, VT, WA

BC, NB, NF, NS, ON, PE, PQ Forb/herb Perennial Introduced 1

Asteraceae
Cichorioideae

Lactuceae

Hieraciinae Hieracium scabrum rough hawkweed AR, CT, DC, DE, GA, IA, IL, IN, KY, MA, MD, ME, MI, MN, MO, NC, NH, NJ, NY, OH, OK, PA, RI, SC, TN, VA, VT, WI

NB, NS, ON, PE, PQ Forb/herb Perennial Native 2

Asteraceae
Cichorioideae

Lactuceae

Hieraciinae Hieracium scouleri var.

albertinum western
hawkweed ID, MT, OR, WA, WY

BC Forb/herb Perennial Native 2

Asteraceae
Cichorioideae

Lactuceae

Hieraciinae Hieracium scoul eri var. cynoglossoides houndstongue

hawkweed CA, ID, OR, WA

BC Forb/herb Perennial Native 2

Asteraceae
Cichorioideae

Lactuceae

Hieraciinae Hieracium scouleri var.

scouleri Scouler’s woollyweed CA, ID, MT, NV, OR, WA, WY Forb/herb Perennial Native 2

Ast eraceae Cichorioideae

Lactuceae

Hieraciinae Hieracium stoloniflorum Not Present in U nited S tates or Canada 2

Asteraceae
Cichorioideae

Lactuceae

Hieraciinae Hieracium umbellatum narrowleaf

hawkweed AK, CO, IA, ID, IL, IN, MI, MN, MO, MT, ND,

NE, NH, O R, SD, WA, WI, WV, WY

AB, BC, LB, MB, NB, NF, NS, NT, ON, PE, PQ, SK, YT Forb/herb Perennial Native 2

Asteraceae
Cichorioideae

Lactuceae

Hieraciinae Hieracium venosum rattlesnakeweed AL, CT, DC, DE, FL, GA, IN, KY, MA, MD, ME, MI, MO, MS, NC, NH, NJ, NY, OH, PA, RI, SC, TN, VA, VT, WY

ON Forb/herb Perennial Native 2

Asteraceae
Cichorioideae

Lactuceae Hypochaeris radicata hairy catsear AK, AL, AR, CA, CO, CT, DC, DE, FL, GA, HI, ID, IL, IN, KY, LA, MA, MD, ME, MI, MO, MS, MT, NC, NH, NM, NJ, NV, NY, OH, OR, PA, Forb/herb Perennial Introduced 3b33

Family Subfamily

Tribe
Subtribe Scientific Name Common Name U.S.

- State Distribution

Canada

- Province Distribution Growth
Habit Duration U

. S

. Nativity Test

Category 1

Hypochaeridinae RI, SC, TN, TX, UT, VA, VT, WA, WI, WV

BC, LB, NF

Asteraceae
Cichorioideae

Lactuceae

Microseridinae Krigia biflora twoflower
dwarfdandelion AL, AR, AZ, CO, CT, DE, GA, IA, IL, IN, KS,

KY, MA, MD, MI, MN, MO, MS, NC, NJ, NM, NY, OH, OK, PA, TN, VA, WI, WV

ON Forb/herb Perennial Native 3b

Asteraceae
Cichorioideae

Lactuceae

Lactucinae Lactuca sativa garden lettuce AL, CA, DC, DE, ID, IL, IN, MA, ME, MI, MO, ND, NM, NY, OH, OK, OR, PA, WA, WV,

Puerto Rico, Virgin Islands Forb/herb Annual

Biennial

Perennial Introduced 3b

Economic

Asteraceae
Cichorioideae

Lactuceae

Lactucinae Lactuca serriola prickly lettuce AL, AR, AZ, CA, CO, CT, DC, DE, FL, GA, HI, IA, ID, IL, IN, KS, KY, LA, MA, MD, ME, MI, MN, MO , MS, MT, NC, ND, NE, NH, NJ, NM, NV, NY, OH, OK, OR, PA, RI, SC, SD, TN, TX, UT, VA, VT, WA, WI, WV, WY

AB, BC, MB, NB, NS, ON, PE, PQ, SK Forb/herb Annual

Biennial Introduced 3b

Asteraceae
Cichorioideae

Lactuceae

Lactucinae Lactuca virosa bitter lett uce AL, CA, DC Forb/herb Annual

Biennial Introduced 3b

Asteraceae
Cichorioideae

Lactuceae Stephanomeriinae Lygodesmia juncea rush skeletonplant AR, AZ, CO, IA, ID, IN, KS, MN, MO, MT, ND,

NE, NM, NV, OK, OR, SD, TX, UT, WA

AB, BC, MB, SK Forb/herb Perenn ial Native 3b

Asteraceae
Cichorioideae

Lactuceae

Microseridinae Microseris nutans nodding

microseris CA, CO, ID, MT, NV, OR, SD, UT, WA, WY

AB, BC Forb/herb Perennial Native 3b

Asteraceae
Cichorioideae

Lactuceae

Lactucinae Prenanthes racemosa purple

rat tlesnakeroot CO, IA, IL, IN, KY, ME, MI, MN, MO, MT, ND,

NE, NJ, NY, OH, PA, SD, WI, WY

AB, BC, MB, NB, NF, NS, ON, PE, PQ, SK Forb/herb Perennial Native 3b

Asteraceae
Cichorioideae

Lactuceae Sonchus asper spiny sowthistle AK, AL, AR, AZ, CA, C O, CT, DC, DE, FL, GA, HI, IA, ID, IL, IN, KS, KY, LA, MA, MD, ME, MI, MN, MO, MS, MT, NC, ND, NE, NH, NJ, NM, Forb/herb Ann ual Introduced 3b34

Family Subfamily

Tribe
Subtribe Scientific Name Common Name U.S.

- State Distribution

Canada

- Province Distribution Growth
Habit Duration U

. S

. Nativity Test

Category 1

Sonchinae NV, NY, OH, OK, OR, PA, RI, SC, SD, TN, TX, UT, VA, VT, WA, WI, WV, WY, Puerto Rico

AB, BC, LB, MB, NB, NF, NS, ON, PE, PQ, SK,

YT

Asteraceae
Cichorioideae

Lactuceae
Sonchinae Sonchus arvensis field sowthistle AK, CA, CO, CT, DC, DE, IA, ID, IL, IN, KS, KY, LA, MA, MD, ME, MI, MN, MO, MS, MT, NC, ND, NE, NH, NJ, NM, NV, NY, OH, OR, PA, RI, SD, TN, TX, UT, VA, VT, WA , WI, WV,

WY

AB, BC, MB, NB, NF, NS, NT, ON, PE, PQ, SK, YT Forb/herb Perennial Introduced 3b

Asteraceae
Cichorioideae

Lactuceae
Sonchinae Sonchus oleraceus common sowthistle AK, AL, AR, AZ, CA, CO, CT, DC, DE, FL, GA,

HI, IA, ID, IL, IN, KS, KY, LA, MA, MD, ME, MI, MN, MO, MS, MT, NC, ND, NE, NH, NJ, NM, NV, NY, OH, OK, OR, PA, RI, SC, SD, TN, TX, UT, VA, VT, WA, WI, WV, WY, Puerto Rico, Virgin Islands

AB, BC, MB, NB, NF, NS, ON, PE, PQ, SK,

YT Forb/herb Annual Introduced 3b

Asteraceae
Cichorioideae

L actuceae Stephanomeriinae Stephanomeria

cichoriacea chicoryleaf

wirelettuce CA Forb/herb
Subshrub Perennial Native 3b

Asteraceae
Cichorioideae

Lactuceae Stephanomeriinae Stephanomeria minor lesser wirelettuce AZ, CA, CO, ID, MT, ND, NM, NV, OR, TX, UT,

WA , WY

BC, SK Forb/herb
Subshrub Perennial Native 3b

Asteraceae
Cichorioideae

Lactuceae Crepidinae Taraxacum officinale common dandelion AK, AL, AR, AZ, CA, CO, CT, DC, DE, FL,

GA,HI, IA, ID, IL, IN, KS, KY, LA, MA, MD, ME, MI, MN, MO, MS, MT, NC, ND, NE, NH, NJ, NM, NV, NY, OH, OK, OR, PA, RI, SC, SD, TN, TX, UT, VA, VT, WA, WI, WV, WY, Puerto

Rico

AB, BC, LB, MB, NB, NF, NS, NT, NU, ON, PE, Forb/herb Perennial Native

Introduced 3b35

Family Subfamily

Tribe
Subtribe Scientific Name Common Name U.S.

- State Distribution

Canada

- Province Distribution Growth
Habit Duration U

. S

. Nativity Test

Category 1

PQ, SK, YT

Asteraceae
Cichorioideae
Cardueae
Centaureinae Acroptilon rep ens hardheads AR, AZ, CA, CO, IA, ID, IL, IN, KS, KY, MI, MN, MO, MT, ND, NE, NM, NV, OH, OK, OR, SD, TX, UT, WA, WI, WY

AB, BC, MB, ON, SK Forb/herb Perennial Introduced 3c

Asteraceae
Cichorioideae
Cardueae
Carduinae Cirsium arvense Canada thistle AK, A L, AR, AZ, CA, CO, CT, DC, DE, IA, ID, IL, IN, KS, KY, MA, MD, ME, MI, MN, MO, MT, NC, ND, NE, NH, NJ, NM, NV, NY, OH, OR, PA, RI, SD, TN, UT, VA, VT, WA, WI, WV, WY

AB, BC, MB, NB, NF, NS, NT, ON, PE, PQ, SK, YT Forb/herb Perennial Introduced 3c

Astera ceae Cichorioideae
Cardueae
Carduinae Cynara scolymus globe artichoke AZ, CA Forb/herb Perennial Introduced 3c

Asteraceae

Asteroideae

Anthemideae

Artemisiinae Artemisia dracunculus tarragon AK, AZ, CA, CO, IA, ID, IL, KS, MA, MN, MO, MT, ND, NE, NM, NV, NY, OK, OR, SD, TX, UT, WA, WI, WY

AB, BC, MB, SK, YT Forb/herb Perennial Native 3d

Economic

Asteraceae

Asteroideae

Anthemideae Chrysantheminae Chrysanthemum

cinerariifolium pyrethrum Cultivated Forb/herb Perennial Cultivated 3d

Asteraceae

Asteroideae

E upatorieae Eupatoriinae Eupatoriadelphus

(Eupatorium)

maculatum spotted trumpetweed CT,GA, IA, IL, IN, KY, MA, MD, ME, MI, MN,

NC, NH, NJ, NY, OH, PA, RI, TN, VA, VT, WI,

WY

MB, NB, NS, ON, PE, PQ Forb/herb Perennial Native 3d

Asteraceae

Asteroideae

Hel enieae

Pectidinae Tagetes erecta Aztec marigold AR, CA, CT, FL, KY, LA, MA, MD, MO, NC, NY, OH, OK, PA, SC, UT, VA, Puerto Rico, Virgin Islands Forb/herb Annual Introduced 3d
Ornamental

Asteraceae

Asteroideae

Heliantheae Dahlia sp. dahlia C ultivated Forb/herb
Subshrub Perennial Cultivated 3d
Ornamental36

Family Subfamily

Tribe
Subtribe Scientific Name Common Name U.S.

- State Distribution

Canada

- Province Distribution Growth
Habit Duration U

. S

. Nativity Test

Category 1

Coreopsidinae

Asteraceae

Asteroideae

Heliantheae

Helianthinae Helianthus annuus common sunflower AK, AL, AR, AZ, CA, CO, CT, DC, DE, FL, GA,

HI, IA, ID, IL, IN, KS, KY, LA, MA, MD, ME, MI, MN, MO, MS, MT, NC, ND, NE, NH, NJ, NM, NV, NY, OH, OK, OR, PA, RI, SC, SD, TN, TX, UT, VA, VT, WA, WI, WV, WY, Puerto Rico

AB, BC, MB, NB, NF, NS, NT, ON, PE, PQ, SK Forb/herb Annual Native 3d
Ornamental

Economic

Asteraceae

Asteroideae

Vernonieae

Vernoniinae Stokesia l aevis Stokes’ Aster AL, FL, GA, LA, MS, NC, SC Forb/herb Perennial Native 3d
Ornamental

Asteraceae Gnaphalioideae Gnaphalieae
Cassiniinae Antennaria dioica stoloniferous pussytoes AK Forb/herb Perennial Native 3d

Asteraceae Gnaphalioideae Gnaphalieae
G naphaliinae Gnaphalium audax Not Present in U nited S tates or Canada

Liliaceae Allium cepa garden onion AR, CA, CT, IL, IN, KS, KY, LA, MA, ME, MI, MO, MS, MT, NC, NH, NY, OH, OR, PA, SC, TX, VT, WI Forb/herb Perennial Introduced 5
Economic

Asclepi adaceae Asclepias syriaca common milkweed AL, AR, CT, DC, DE, GA, IA, IL, IN, KS, KY,

LA, MA, MD, ME, MI, MN, MO, MS, MT, NC, ND, NH, NE, NJ, NY, OH, OK, OR, PA, RI, SC, SD, TN, TX, VA, VT, WI, WV Forb/herb Perennial Native 5

Chenopodiaceae Beta vulgaris common beet AL, CA, CT, MA, ME, MI, MO, MT, NC, NH, NY, OR, PA, SC, TX, UT, VA, WV Forb/herb Annual

Biennial Introduced 5
Economic

Lamiaceae Monarda fistulosa wild bergamot AL, AR, AZ, CO, CT, DC, DE, GA, IA, ID, IL, IN, KS, KY, LA, MA, MD, ME, MI, MN, MO

, MS, MT, NC, ND, NE, NH, NJ, NM, NV, NY, OH, OK, OR, PA, RI, SC, SD, TN, TX, UT, VA, VT, WA, WI, WV, WY Forb/herb
Subshrub Perennial Native 5

Papaveraceae Papaver nudicale Iceland poppy Cultivated

AK Forb/herb Biennial

Perennial Cultivated 5
Ornament al37

Family Subfamily

Tribe
Subtribe Scientific Name Common Name U.S.

- State Distribution

Canada

- Province Distribution Growth
Habit Duration U

. S

. Nativity Test

Category 1

YT
Apiaceae Petroselinum crispum parsley AR, CA, CT, FL, GA, HI, IA, ID, KS, LA, MA, MD, MI, MS, MT, NC, NV, NY, OH, PA, RI, TX, SC, UT, WA, Puerto Rico Forb/herb Annual

Biennial Introduced 5
Economic

Fabaceae Pisum sativum garden pea CA, CT, FL, IL, KS, KY, LA, MA, ME, MI, MO, MS, NC, NH, NY, OK, OR, PA, SC, UT, VA,

WA Forb/herb

Vine Annual Introduced 5
Economic

Fabaceae Vicia faba horsebean CA, CT, DC, MA, MD, ME, MT, NY, OR, PA, VA, VT, WA Forb/herb

Vine Annual Introduced 5
Economic

1 Test Categori es: 1. Genetic types of target weed; 2. Species of the same (or closely related) genus; 3. Species in the same family as the target weed (3a. Plants in same subtribe; 3b. Plants in same tribe; 3c. Plants in same subfamily; and 3d. Plants in same family); 4 . Threatened and endangered species in the same family; and 5. Species in other families.38

Appendix 2. Description of plants chosen for each category for host specificity testing ( f rom Littlefield et al., 2008)

CATEGORY 1: Genetic types of Hieracium (v arieties, races, forms, genotypes, apomicts, etc.).

The natural host of A. subterminalis is mouse

- ear hawkweed, H. pilosella . Although specific genotypes of H. pilosella were not tested, plants from Europe, New Zealand, and the United States (Washington) were tested. In general

, a high proportion of these plant collections supported gall development (54 to 97 percent), although infestation levels probably varied due to testing conditions. Since galls were also induced in other species within the subgenu s Pilosella

, it is thought that A. subterminalis is not highly specialized or limited to a particular H. pilosella genotype. Host specificity tests conducted for New Zealand indicated that orange hawkweed, H. aurantiacum , also supported gall development a nd the emergence of viable adults. Orange hawkweed is more widespread and abundant in the western United

States and Canada and

, therefore

, a more important target weed. North American testing also indicated that this plant host is suitable, but perhaps l ess so compared to H. pilosella

. Infestation levels varied from 13 to 67 percent. Although H. pilosella appears to be genetically diverse (Trewick et al. , 2004), H. aurantiacum has a very limited genetic diversity, especially for North American populatio ns (Loomis, 2007). Therefore, Littlefield

et al. (2008) speculate that differences observed in infestations levels were due more to environmental conditions than genotypic differences in H. aurantiacum

.

CATEGORY 2: North American species in the same genu s as Hieracium , divided by subgenera, including economically and environmentally important plants.

2.a. Species in the same subgenus ( Pilosella):

This subgenus is not represented in the native flora of North America

- all members of this subgenus (or ge nus) are European. For North American testing H. caespitosum

, H. glomeratum

, H. piloselloides

, H. stoloniflorum

, H. flagellare

, and H. floribundum were included. Hieracium praealtum was also tested in New Zealand but was not attacked. Galls

were induced only on H. flagellare and H. floribundum . Gaskin and Wilson (2007) indicated two distinct species grouping within the Pilosella

. Hieracium flagellare is more closely

related to both H. pilosella and H. aurantiacum

. Hieracium floribundum however, is mor e closely related to the group containing H. caespitosum

, H. glomeratum , and H. piloselloides

. Although H. floribundum was attacked in tests conducted at MSU, it was not infested in

CABI tests. Hieracium floribundum is thought to be a cross between H. ca espitosum and H.

lactucella , although back crosses with other Hieraciums (e.g. H. aurantiacum ) sometimes occur (Krahulec et al. , 2008). H ieracium stoloniflorum is another cross ( H. aurantiacum x H. pilosella ) (Krahulec et al. , 2008), although based upon h ost utilization of H. pilosella and

H. aurantiacum in the host specificity tests H. stoloniflorum was expected to be a potential host, but no gall induction was observed.39

2.b. Species in the subgenus Hieracium :

From the subgenus Hieracium , the North A merican representative to this subgenus was tested, H. umbellatum , and no gall development occurred. Although H. canadense has previously been placed in this subgenus, recent work by Gaskin and Wilson (2007) placed this species in the subgenus Chionoraciu m . Other representatives ( H. lepidulum

, H.

murorum , and H. sabaudum ) to this subgenus were tested by CABI and in New Zealand, but not attacked by A. subterminalis

.

The subgenus Hieracium is poorly represented in North America. Hieracium umbellatum is Holarctic in distribution and is thought to be a native. Other subgenus Hieracium species in

North America include H. argillaceum

, H. murorum

, H. groenlandicum , and H. sabaudum ; all of which are introduced. However, these species are generally not consid ered noxious

weeds.

Based on host specificity testing

, it is unlikely that any plant in this subgenus would be utilized as a host by A. subterminalis since none are stoloniferous (produce stolons). A.

subterminalis attacks and causes galls only in stolo ns and not other plant parts.

2.c. Species in the subgenus Chionoracium :

Subgenus Chionoracium is represented throughout North America. Sixteen species representative of the geographic range of native species were tested

. From the Northwest

and Inter mountain region, H. gracile, H. longiberbe

, H. parryi, and H. scouleri var. albertinum and scouleri, and the white flowered H. albiflorum were tested

. From southern Oregon and northern California, H. bolanderi

, H. horridum , and H. greenei were used. From California, H. argutum was tested. From the Southwest, H. carneum and H. fendleri were tested

, and from the East and Midwest, H. longipilum

, H. gronovii

, H scabrum , and H.

venosum were tested

. Hieracium canadense was also tested and its distributions ex tend over

much of the northern United States and southern Canada. None of these species were infested by A

. subterminalis and none of the hawkweed species associated with the subgenus

Chionoracium produces stolons in which the gall wasp induces galls. It is highly unlikely

that A

. subterminalis would utilize these plants as hosts.

CATEGORY 3: North American species in other genera in the Asteraceae family, divided by subtribe, tribe, and subfamily, including economically and

environmentally important pla nts.

The Asteraceae is the largest plant family and is divided into 3 subfamilies, 17 tribes, and

numerous subtribes. In developing our list of plants to be tested, we followed the reclassification of the Asteraceae by Bremer (1994).40

3.a. Species in the same subtribe (Hieraciinae) as Hieracium :

Other genera in the Hieraciinae subtribe include Andryala, Arnoseris, Hispidella, Hololeion,

and Tolpis

. No species from these genera were tested since they are not native to North America, nor do they contai n any economically important plants in North America (Bremer

, 1994). Only two species, Arnoseris minima and Tolpis barbata are reported to occur in the

U nited States and Canada (Flora of North America North of Mexico , 2008; USDA

- NRCS Plants Database 2008)

.

3.b. Species in different subtribes of the same tribe (Lactuceae) as Hieracium :

The Lactuceae is one of the best known tribes of the Asteraceae and is well supported as a distinct monophyletic group. Subtribal and generic classifications are more d efined in this tribe than in most other tribes (Bremer

, 1994). The Lactuceae are set apart from other Asteraceae by a ligulate capitula, milky latex, and absence of oil ducts (except in Scolymus ), although none of these

characteristics are restricted to t he Lactuceae alone (Mañez et. al

. , 1994). Besides the Hieraciinae, there are five Lactuceae subtribes that contain species native to North America (Crepidinae, Lactucinae, Malcothrinae, Microseridinae, and Stephanomeriinae); four subtribes with introduced species (Catananchinae, Hypochaeridinae = Leontodontinae, Scorzonerinae, and Sonchinae); and two introduced genera ( Cichorium and Scolymus ) that have not been assigned to a subtribe (Bremer

, 1994).

Two genera in the Crepidinae subtribe ( Crepis and Taraxa cum ) contain species native to North America (Bremer

, 1994). Crepis is an important genus to test because of the number of native and a few introduced species in the United States (Flora of North America North of Mexico 2008, USDA

NRCS

, 2008). The two Cr epis species we tested were Crepis atribarba (native) and Crepis biennis (introduced). Taraxacum is another important genus to test because of the presence of native species in Western North America (USDA

- NCRS

, 2008), some of which are threatened, endange red, or sensitive (see Category 4). The c osmopolitan species Taraxacum officinale was tested , and in New

Zealand

, T. magellanicum was also tested.

Within the Lactucinae, two genera contain species native to North America: Lactuca and Prenanthes (Bremer

, 1994 ; USDA

- NRCS

, 2008). Lactuca sativa (lettuce) was included because of its economic importance. In addition, Lactuca serriola and L. virosa were tested since they are widespread

weeds. Prenanthes sagittata was tested since it is a native.

The Microse ridinae contains the following genera native to North America: Agoseris

, Krigia

, Microseris

, Nothocalais

, Phalacroseris

, Pyrrhopappus

, Stebbinsoseris , and Uropappus (Bremer

, 1994; USDA

- NCRS

, 2008). Four native species: Microseris nutans

, Agoseris glauca

, A

. grandifolia , and Krigia biflora were included in tests. In New Zealand, Microseris scapigera was used.

The Stephanomeriinae contains the following genera native to North America: Chaetadelpha

, Lygodesmia

, Prenanthella

, Rafinesquia

, Shinnersoseris , and Stephanomeria (Bremer

, 1994 ; USDA

-41

NCRS

, 2008). T hree native western species were tested : Lygodesmia juncea

, Stephanomeria
cichoriacea, and S. minor (= S. tenuifolia ).

The Malcothrinae contains the following genera native to North America: Anisocoma

, A trichoseris

, Calycoseris

, Glyptopleura

, Malacothrix , and Pinaropappus (Bremer , 1994; Flora of North America

North of Mexico , 2008; USDA

- NCRS

, 2008). Most are native to the Southwestern United States,

except Glyptopleura (western annuals) and Malacothrix ( western annuals and perennials). No species from this subtribe were tested because sources for seeds and/or plant material were identified

.

Of the four subtribes with introduced species but no natives, Catanache caerula , an introduced

ornamental from the Catananchinae was included

. For the subtribe Sonchinae: Sonchus arvensis

, S.

asper , and S. oleraceus were tested; plus S. kirkii

, which was also tested in New Zealand. No species from the Hypochaeridinae, or Scorzonerinae were included , as these subtrib es are not native to North America and contain no economically important introduced species (Bremer , 1994; USDA

NCRS

, 2008). Among the introduced genera unassigned to a subtribe, Cichorium intybus (chicory)

was used in both New Zealand and North American tests becaus e of its economic importance.

In summary

, 26 species belonging to other subtribes within Lactuceae were tested during North American and New Zealand host specificity tests. None were utilized by A. subterminalis as a host.

3.c. Species in different tribes in the same subfamily (Cichorioideae):

According to Bremer (1994), the subfamily Cichorioideae contains three tribes with natives in North America (Cardueae, Mutisieae, and Vernonieae) plus a tribe with some introduced ornamentals (Arct oteae). The Mutisieae and the Vernonieae are believed to be closely related to the Lactuceae (Mañez et al.

, 1994; Tomb

, 1977). Like the Lactuceae, several species of Mutisieae and Stokesia have ligulate corollas (Tomb

, 1977). Stokesia laevis , a native o rnamental in the Veronieae was used for testing. From the Cardueae, we used two weedy species that can reproduce asexually by lateral roots, Acroptilon repens (Russian knapweed) and Cirisium arvense (Canada thistle), as well as Cynara scolymu s (globe

arti choke). Both Carthamus tinctorius (safflower) and globe artichoke were tested from this subfamily for the New Zealand tests. Galls were not induced by A. subterminalis on any of these species.

3.d. Species in different subfamilies in the same family (A steraceae):

Besides the Cichorioideae, there are two additional subfamilies (Barnadesioideae and Asteroideae) in the Asteraceae family (Bremer

, 1994).

The Barnadesioideae comprise nine genera and are exclusively South American. Because there are no sp ecies native to North America (Bremer

, 1994), no Barnadesioideae were included in testing.42

The Asteroideae include the majority of the Asteraceae and comprise eight tribes with species native to the United States (Anthemideae, Astereae, Eupatorieae, Gna phalieae, Helenieae, Heliantheae, Plucheeae, and Senecioneae), two additional tribes with ornamental species (Calenduleae and Inuleae), and eight genera unassigned to a tribe (Bremer

, 1994). Although acetylenes are relatively rare in the Lactuceae, those which are present belong to a special group which may link the Lactuceae chemotaxonomically with the Astereae and the Anthemideae (Mabry and Bohlmann

, 1977). In combined North American and New Zealand tests, 12 species were used representing the eight sub tribes of the Asteraceae. Galls were not induced on any of these species.

Category 3 Summary : From testing these 42 species in all of Category 3, Littlefield et al. (2008) obtained sufficient evidence to conclude that the feeding range of this gall wa sp is restricted to the genus Hieracium , subgenus Pilosella , and that species in other subfamilies of the Asteraceae family are not at significant risk.

C ATEGORY 4: Threatened and endangered species in the Asteraceae family, divided

by subgenus, genus, su bfamily, and tribe.

4.a. Species in the same subgenus ( Pilosella):

There are no Hieracium species belonging to subgenus Pilosella listed as threatened, endangered, or sensitive.

4.b. Species in the same genus as Hieracium :

While there are no threat ened or endangered species of Hieracium in the United States (or Canada), several states identify one or more Hiearcium species as being restricted in

distribution.

The following is a list of S tates that list one or more Hiearcium species on their Speci al Plants List (or equivalent).

Pennsylvania http://www.dcnr.state.pa.us/forestry/pndi/fullplants.asp lists H. kalmii and H.

trailii

.

Ohio http://www.dnr.state.oh.us/odnr/dnap/heritage/plantlst.html lists H. canadense and H. longipilum

.

Utah http://www.nr.state.ut.us/dwr/dwr.htm lists H. fendleri.

In Oregon, the Oregon Natural Heritage Program http://www.heritage.tnc.org/nhp/us/or/vd

l.htm lists H. bolanderi

, H. greenei , and H. horridum.43

Tennessee http://www.state.tn.us/environment/nh/tnplants.html lists H. longipilum , and H.

scabrum

.

Michigan http://www.dnr.state.mi.us/wildlife/heritage/ lists H. longipi lum.

N ative Hieracium species were selected from across the geographic range of the genus throughout North America. All of the Hieracium species native to North America belong the subgenus Chionoracium

, none of which were infested by A. subterminalis

.

4. c. Species in the same subtribe (Hieraciinae) as Hieracium :

There are no threatened, endangered, or sensitive species within the same subtribe as

Hieracium.

4.d. Species in different subtribes of the same tribe (Lactuceae) as Hieracium :

Four of the Lactuceaae subtribes (besides Hieraciinae) have threatened, endangered, or sensitive species in the continental United States (USFWS

, 1993 ; USFWS

, 1996). Because obtaining plant material of threatened, endangered, and sensitive species can be difficult an d can further decimate populations, listed species were not tested

. Instead

, a more common member from each genus was selected as a surrogate

.

Two Crepidinae species, Taraxacum californicum Munz & Johnston, proposed endangered,

and T. officinale ssp. cer

atophorum (Ledeb.) Schinz ex. Thellung (syn. T. carneocoloratum ), sensitive, are listed in the continental Uni ted States ( http://www.fws.gov/r9endspp/endspp.html ). T he more common species Taraxacum

o fficinale was tested (listed in Category 3.b.). The Lactucinae has two species of Prenanthes

listed as sensitive [ P. barbata (Torr. & Gray) Milstead and P. boottii (DC.) Gray]. T he more common native species, Prenanthes sagittata

, was substituted (listed in Category 3.b.). The Microseridinae has two species of Microseris listed as sensitive ( M. decipens Chambers and

M. howellii Gray). T he more common native species, Microseris nutans

, was tested (listed in Category 3.b.). The Stephanomeriinae has one f ederally endangered Stephanomeria ( S.

malheurensis Gottlieb), one sensitive Stephanomeria ( S. blairii Munz. & Johnston) and one

sensitive Lygodesmia species ( L. doloresensis S. Tomb). I nstead Stephanomeria minor (= S. tenuifolia ), S. cichoriacea

, and Lygo desmia juncea were tested (listed in Category 3.b.)

4.e. Species in different tribes in the same subfamily (Cichorioideae):

The Cardueae has several Cirsium species listed as threatened, endangered, or sensitive in the

continental United States ( http://www.fws.gov/r9endspp/endspp.html ): Cirsium fontinale var. fontinale ( fountain thistle), Cirsium fontinale var. obispoense (Chorro Creek bog thistle), Cirsium hydrophilum var. hydrophilum (Suisun this tle), Cirsium loncholepis (La Graciosa thistle), and Cirsium pitcheri (Pitcher's thistle). All but the last species is federally endangered, while C. pitcheri is threatened. Because obtaining achenes and/or plant material of threatened, endangered, and s ensitive species can be difficult and can further decimate44

populations, these rare species were not tested

. Cirsium arvense

, a more common member from this genus which also reproduces asexually by lateral roots was sel e cted

.

4.f. Species in different s ubfamilies in the same family (Asteraceae):

At this level, no representatives from genera with threatened, endangered, or sensitive

individuals were tested

. With over 20 genera with federally listed threatened or endangered species and over 70 additiona l genera with sensitive species in the continental United States, the number of species we would need to test is prohibitively large. Testing was conducted on representatives to the various subtribes of Asteraceae (Category 3.d). It was evident from

MSU testing and testing conducted for New Zealand that A. subterminalis was restricted in its host range and plants outside the genus Hieracium subgenus Pilosella are not at risk of attack by this agent.

CATEGORY 5:

North American species in other families i n the Asterales order that have some phylogenetic, morphological, or biochemical relationship to the target weed, including economically and environmentally important plants.

Neither Cronquist nor Dahlgren list any families other than the Asteraceae in th e Asterales order; however, Thorne lists the Calyceraceae as belonging in the Asterales. Cronquist places the Calyceraceae in the Calycerales while Dahlgren places it in the Dipsacales. Since two out of three systems list the Calyceraceae in an order oth er than Asterales, this family is

discussed in Category 6.

CATEGORY 6:
North American species in other orders that have some morphological or biochemical relationship to the target weed, including economically and

environmentally important plants.

6.a. Species in other orders that are phylogenetically related to the Asteraceae:

The Asteraceae form such a well

- defined group that they are sometimes considered systematically isolated. The most closely related families are generally considered to be the

Ca lyceraceae, Campanulaceae sensu lato , and Goodeniaceae (Bremer

, 1994). The Calyceraceae contain six genera with about 60 species in southern South America (Bremer

, 1994). One species, Acicarpha tribuloides , is listed as present in North America (Kartesz

and Kartesz

, 1980). The Campanulaceae sensu lato contain about 85 genera and more than

2

, 200 species (Bremer

, 1994). There are about 23 genera and 290 species in the United States and Canada (Zomlefer

, 1994). The Campanulaceae have been shown to be

chem otaxonomically linked to the Asteraceae (Mabry and Bohlmann

, 1977). The Goodeniaceae contain 12 genera and 400 predominately Australian species (Bremer

, 1994). One genus, Scaevola , has 2 species listed as present in the central and s outhern United States (USDA

- NRCS

, 2008 ). Due to the apparent specificity of A. subterminalis , plants within

these orders were not tested (Littlefield et al.

, 2008)

.45

6.b. Species in other orders that are biochemically similar to the Asteraceae:

Species in the Lactuceae are characterized, in part, by their milky latex. However, more than 12,500 species in 900 genera and 20 families have been identified worldwide that produce latex (Metcalfe

, 1967). Over 300 species in the United States have been shown to contain latex (Buch anan
, 1978). The following four latex

- producing species from different families

were selected for testing: Allium cepa

, Asclepias syriaca

, Monarda fistulosa L., and Papavar

nudicaule L. All a re native or introduced to the w estern United States. None of these latex

producing species were attacked by A. subterminalis (Littlefield et al.

, 2008)

.

The Lactuceae also differ phytochemically in that their sesquiterpene lactones are predominately guaianolides

, whereas the other Asteraceae subfamilies contain pla nts with considerable portions of other sesquiterpene lactones (Wapshere

, 1983). Unlike most other Asteraceae, the Lactuceae possess either no or a low level of polyacetylene compounds (Sorensen

, 1977). The Apiaceae (= Umbellifereae) have been shown to b e chemotaxonomically linked to the Asteraceae (Mabry and Bohlmann

, 1977). Petroselinum crispum (parsley)

, which is economically important and chemically similar to the Asteraceae

, was not infested during the New Zealand tests (Littlefield et al.

, 2008)

.

6.c. Selected cultivated species in other orders:

No cultivated species in other plant orders were tested , although several species were tested for the New Zealand project

.

CATEGORY 7:

Any plant on which the biological control agent or its close relativ es (within the same genus) have been previously recorded to feed and/or reproduce.

Cynipid wasps of the genus Aulacidea generally have a narrow host range, confined to the family Asteraceae. A number of species utilized by other Aulacidea spp. wasps, inc luding Acroptilon

, Hieracium, Hypochoeris

, Lactuca

, Prenanthes

, Senecio

, Solidago , Sonchus , and Tragopogon

, were tested. Galls were only induced on several species belonging to the

Hieracium subgenus Pilosella (Littlefield et al.

, 2008)

.

Conclusions

Ba sed upon test results from M ontana S tate U niversity , as well as testing of A. subterminalis for importation into New Zealand , h ost utilization by A. subterminalis is confined to a few closely related hawkweed species all of which are Old World species. Na tive North American hawkweeds are precluded from attack in t hat they do not produce stolons, the

location where the gall wasp induces galls and completes its development. All native North American hawkweeds are phylogentically distant and distinct from th e exotic, and often weedy, hawkweeds of the Pillosella group (Littlefield et al.

, 2008)

.46

Appendix 3

. Galling observed in multiple

- choice and larval development tests with A.

subterminalis (combined results for New Zealand host specificity tests 1995 to 19 97; taken from Syrett et al.

, 1998).

Test Plant Species Total No. of Plants

Offered Attacked

Asteraceae

Lactuceae

Subgenus Pilosella

Hieracium pilosella L. EUR 76 74

H. pilosella L. NZ 14 10

H. aurantiacum L. 4 2

H. caespitosum Dumort EUR 6 0

H. caespitosum Dumort USA 5 0

H. praealtum Gochnat 3 0

H.x stoloniferum Waldst. et Kit 3 0

Subgenus Hieracium 0

H. lepidulum (Stenstroem) Omang 6 0

H. murorum L. 7 0

H. sabaudum L. 8 0

Representatives of other Subtribes of Lactuceae

Cichor ium intybus L. 7 0

Embergia grandifolia (Kirk) Boules 4 0

Hypochoeris radicata L 8 0

Lactuca sativa L. 4 0

Microseris scapigera (Solex A.Cunn.) Sch.Bip. 5 0

Picris hieracioides L. 7 0

Sonchus kirkii Hamlin 6 0

Sonchus oleraceus L. 6 0

Taraxacum off

icinale L. 5 0

Taraxacum magellanicum Schutz

- Bip. 2 0

Tragopogon porrifolius L. 6 0

Anthemidae

Artemesia dracunculus L. 1 0

Chrysanthemum cinerariifolium (Treviri) Vis. 7 0

Astereae

Celmisia sp. 3 0

Olearia avicenniifolia (Raul.) Hook f. 4 0

C ardueae

Carthamus tinctorius L. 7 0

Cynara scolymus L. 6 0

Heliantheae

Helianthus annuus L. 6 047 Test Plant Species Total No. of Plants

Offered Attacked

Senecioneae

Brachyglottis monroi Hook. f. 2 0

Other Plant Families

Apiaceae: Patr

oselinum crispum (Miller) A.W. Hill 8 0

Brassicaceae: Brassica oleracea L. 7 0

Cannaceae: Canna edulis Ker

- Gawl. 9 0

Caryophyllaceae: Dianithus barbatus L. 7 0

Cyperaceae: Carex testacea Sol ex Booth Hook. f. 5 0

Fabaceae: Trifolium repens L. 7 0

I ridaceae: Gladiolus communis L. 8 0

Lamiaceae: Mentha sp. 8 0

Liliaeae: Allium cepa L. 8 0

Malvaceae: Althea rosea L. 5 0

Myrtaceae: Leptospermum scoparium J.R. et G. Forst. 3 0

Oleaceae: Olea europaea L. 2 0

Poaceae: Poa colensoi Hook. f. 7 0

Poace ae: Agrostis tenuis Sibth. 5 0

Poaceae: Festuca novae

- zelandiae (Hack.), Ckn 7 0

Polyganaceae: Rumex acetosella L. 7 0

Rutaceae: Citrus sp. 8 0

Scrophulariaceae: Antirrhinum majus L. 2 0

Solanaceae: Lycopersicon esculentum Miller 8 0

Theaceae: Camell

ia japonica L. 8 0

Urticaceae: Urtica dioica L. 7 048

Appendix 4. No

- choice oviposition and larval development tests with A.

subterminalis conducted from 2000 to 2006 at CABI

- Europe and Montana State University (Littlefield et al., 2008).

Test P lan t 1 No. Reps Reps. Infested Mean No. Gall Clusters/Rep ( + SE) No. %

ASTERACEAE

Tribe: Lactuceae

Subtribe: Hieraciinae Subgenus: Pilosella

Hieracium aurantiacum ID 15 2 13.3 0.13 (0.09)

H. aurantiacum MT 1 0 0 0

H. aurantiacum NZ 6 4 66.7 1.33 (0.49)

H. aurantiacum ID, MT 44 17 38.6 0.89 (0.21)

H. caespitosum ID 33 0 0 0

H. caespitosum ID 3 0 0 0

H. flagellare NH 16 8 50.0 1.62 (0.79)

H. floribundum US 9 0 0 0

H. floribundum 17 9 52.9 1.24 (0.48)

H. glomeratum BC 2 0 0 0

H. glomeratum WA 6 0 0 0

H. glomeratum ID 7 0 0 0

H. pilosella EUR 28 23 82.1 2.68 (0.42)

H. pilosella US 13 11 84.6 1.92 (0.62)

H. pilosella WA 46 25 54.3 1.35 (0.29)

H. piloselloides US 6 0 0 0

H. piloselloides 11 0 0 0

H. stoloniflorum Eur 9 0 0 0

Subtribe: Hieraciinae Subgenus: Hieracium

H. umbellatum 13 0 0 0

Subtribe: Hieraciinae Subgenus: Chionoracium

Hieracium. albiflorum 2 0 0 0

H. albiflorum 18 0 0 0

H. argutum 3 0 0 0

H. argutum 18 0 0 049 Test Plant 1 No. Reps R eps. Infested Mean No. Gall Clusters/Rep ( + SE) No. %

H. bolanderi 15 0 0 0

H. canadense 7 0 0 0

H. canadense 15 0 0 0

H. carneum 1 0 0 0

H. carneum 15 0 0 0

H. fendler

i 3 0 0 0

H. fendleri 10 0 0 0

H. gracile 7 0 0 0

H. greenei 14 0 0 0

H. gronovii 3 0 0 0

H. gronovii 17 0 0 0

H. horridum 3 0 0 0

H. longiberbe 8 0 0 0

H. longipilum 15 0 0 0

H. parryi 11 0 0 0

H. scabrum 15 0 0 0

H. scouleri var. albertinum 6 0 0 0

H. scouleri var. albertinum 11 0 0 0

H. scouleri var. cynogloss oides 17 0 0 0

H. venosum 5 0 0 0

Other Subtribes of Lactuceae

Subtribe: Catananchinae

Catananche caerula 6 0 0 0

Subtribe: Crepidinae

Crepis atribarba 10 0 0 0

Crepis biennis 15 0 0 0

Taraxacum officinale 6 0 0 0

Sub tribe: Hypochaeridinae

Hypochoeris radicata 6 0 0 0

Subtribe: Lactucinae

Lactuca sativa 9 0 0 050 Test Plant 1 No. Reps Reps. Infested Mean No. Gall Clusters/Rep ( + SE) No. %

Lactuca serriola 3 0 0 0

Lactuca virosa 6 0 0 0

Prenanthe s racemosa 4 0 0 0

Subtribe: Microseridinae

Agroseris glauca 16 0 0 0

Agoseris grandiflora 5 0 0 0

Agroseris grandifolia 3 0 0 0

Krigia biflora 3 0 0 0

Krigia biflora 13 0 0 0

Microseris nutans 11 0 0 0

Subtribe: Sonchinae

Son chus arvensis 6 0 0 0

Sonchus asper 8 0 0 0

Sonchus oleraceus 6 0 0 0

Subtribe: Stephanomeriinae

Lygodesmia juncea 14 0 0 0

Stephanomeria cichoriacea 14 0 0 0

Stephanomeria minor 5 0 0 0

Subtribe: unassigned

Cichorium intybus 10 0 0 0

Other Tribes of Asteraceae

Tribe: Anthemideae

Artemisia dracunculus 6 0 0 0

Chrysanthemum cinerariifolium 9 0 0 0

Tribe: Cardueae

Acroptilon repens 8 0 0 0

Cirsium arvense 10 0 0 0

Cynara scolymus 9 0 0 0

Tribe: Eupatorieae

Eupatorium maculatum 9 0 0 051 Test Plant 1 No. Reps Reps. Infested Mean No. Gall Clusters/Rep ( + SE) No. %

Tribe: Gnaphalieae

Antennaria dioica 9 0 0 0

Gnaphalium audax 9 0 0 0

Tribe: Helenieae

Tagetes erecta 9 0 0 0

Tribe: Heliantheae

Dahlia sp. 3 0 0 0

Helianthus annuus 9 0 0 0

Tribe: Vernonieae

Stokesia laevis 5 0 0 0

OTHER FAMILIES

Apiaceae : Petroselinum crispum (parsley) 3 0 0 0

Asclepiadacea : Asclepias syriaca (common milkweed) 7 0 0 0

Chenopodiaceae : Bet a vulgaris (beet) 9 0 0 0

Fabaceae : Pisum sativum (garden pea) 7 0 0 0

Fabaceae : Vicia faba (broad bean) 5 0 0 0

Lamiaceae : Monarda fistulosa (wild bergamot) 6 0 0 0

Liliaceae : Allium cepa (onion) 8 0 0 0

Papavaracea : Papaver nudicaule (Islandic poppy ) 3 0 0 0

1 Plant species highlighted in blue indicate those tested at Montana State University.52

Appendix 5

. Response to comment s on draft EA

Four comments were submitted on the draft environmental assessment for release of A.

subterminals for biolo gical control of hawkweeds. A commenter from t he Florida Department of Agriculture and Consumer Services support ed the release of the gall wasps as biological control agents. Specific issues were raised by the other three

commenters

. The issues raised a re indicated in bold text and the response follows.

An anonymous commenter indicated general concern with the release of A. subterminalis, as well as other concerns with APHIS that are out of the scope of

this EA. The commenter indicated that more test s should be done to demonstrate the safety of release of A. subterminalis.

Extensive host specificity testing was conducted over a 6

- year period that demonstrated the safety of A. subterminalis to native plants. Study results were reviewed by The

Tech nical Advisory Group for the Biological Control Agents of Weeds (TAG) and the

release of A. subterminalis was recommended by the TAG. TAG members that reviewed the release petition included representatives from APHIS, Cooperative State Research, Education , and Extension Service (now National Institute of Food and Agriculture), Forest Service, Environmental Protection Agency, U.S. Army Corps of Engineers, the National Plant Board, and representatives from Canada.

A commenter from the Alaska Association o f Conservation Districts supported the

release of Aulacidea subterminalis but raised two issues. The first was regarding placing a hold on the potential release of A. subterminalis in Alaska until field tests prove that it can survive and impact either or ange hawkweed ( Pilosella aurantiaca ( =Hieracium aurantiacum) ) or Hieracium umbellatum

.

There are no current plans to release the wasp in Alaska. Any releases made within that state will be largely dependent upon Alaskan cooperators at the federal, stat e, county or local level. It will likely be a number of years before this gall wasp will be readily available for general release and redistribution. By that time data from the field indicating the potential impact of the wasp on orange hawkweed may be a vailable. No North American native hawkweeds were infested in laboratory host specificity tests, including Hieracium umbellatum . Therefore, it is unlikely that A. subterminalis would survive on that species in Alaska.

The second issue was in regards to the possible utilization of the native hawkweed

Hieracium triste by Aulacidea subterminalis

. According to the Plants Database (USDA, NRCS, 2010) H. triste (woolly hawkweed) has two varieties: H. triste var. fulvum and H. triste var . triste

. Hieracium t riste var. fulvum has been reported only from Alaska, whereas H. triste var. triste is more widespread occurring in Alaska and in the Canadian provinces of Alberta, British Columbia, Yukon, and Northwest

Territories. The Plants Database also lists several varieties of Hieracium gracile (slender hawkweed): H. gracile var. alaskanum found in Alaska ; H. gracile var.53

detonsum located in California, Colorado, Idaho, Oregon, and Washington; H. gracile

var. gracile found in Alaska and most of the western United States; and H. gracile var. yukonense also found in Alaska. Based upon analyses of certain sequences of chloroplast DNA conducted by Gaskin and Wilson (2007), H. triste and H. gracile are very genetically similar. This data appears to lend support to the synonymization of H. gracile with H. triste by some authors (Brouillet et al., 2010; eFloras.org ,2010). Furthermore, both plants seem to share similar life habits and ecological niches (eFloras.org , 2010; Rice and Halpop, 2009). Phylogenetically, this species (or species group) is contained in the subgenus Chionoracium , a subgenera of the Hieracium to which the majority of native North American hawkweeds belong. Hieracium gracile

var . gracile was tested in host specificity studies but was not infested by A.

subterminalis . In addition, no North American native hawkweeds were infested in host specificity tests.

Gall induction is a complex biochemical and morphological process; thus, gall

- inducing insects tend to be very host and tissue specific, makin g them attractive for use as biological control agents of weeds. Aulacidea subterminalis only induces galls at the tips of stolons which are only produced by invasive hawkweeds of the Pilosella genus (formerly considered a subgenus) and not by any of the native hawkweeds. There is no evidence that suggests that A. subterminalis will utilize lateral roots or rhizomes should they be produced by native plant species. Because A. subterminalis is a stolon feeder and host range is restricted to a small group of related invasive hawkweeds of the genus

Pilosella ; the risk to native hawkweeds, which do not produce stolons, is extremely

low.

References

- Brouillet, L., F. Coursol, M. Favreau, and M. Anions (compilers). 2010. VASCAN, the

Database of Vascular Plan ts of Canada. http://data.canadensys.net/vascan/ ( last

accessed January 25, 2011 )

.

eFloras.org. 2010. Flora of North America. Vol. 19, 20 and 21 Page 280, 282, 291. http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=250066959 last

accessed January 19, 2011.

Gaskin, J.F. and L.M. Wilson. 2007. Phylogenetic Relationships Among Native and

Naturalized Hieracium (Ast eraceae) in Canada and the United States Based on Plastid DNA Sequences. Systematic Botany 32: 478

– 485.

Rice, P., and J. Halpop. 2009. Hawkweed Identification. Montana State University Extension. http:// msuextension.org/publications/ AgandNaturalResourc es/EB0187.pdf. USDA, NRCS. 2010. The PLANTS Database. National Plant Data Center, Baton Rouge, LA 70874

- 4490 USA. http://plants.usda.gov (consulted on 03 December 2010)

.54

A commenter from Habitat Conservation, and Environmental Contaminants, U.S.

Fish a nd Wildlife Service, Region 8 Ecological Services, Sacramento, CA raised to

issues of concern. The first comment was in regards to the geographic, ecological

, and economic impact of invasive hawkweed species. The commenter believed that the purpose and need for the proposed action does not adequately describe the impact of non

- native hawkweeds in a manner that justifies the risk of introduction

of a non

- native insect.

The Pacific Northwest (PNW) is in a phase of exponential expansion and colonization by invasive hawkweed species. The number of counties in the PNW reporting new infestations of both orange ( P. aurantiaca ) and meadow hawkweed ( P. caespitosa ) has significantly increased over the past 10

– 15 years (Rice, 2010). In Montana it is

estimat ed that 57,000 acres were infested by invasive hawkweeds in 2000, but as of 2008 this estimate has been revised to well over 120,000 acres (M. Funk, Montana Hawkweed Coordinator, pers. comm.). It has been estimated that the annual increase

of invasive ha wkweeds within Flathead County Montana is over 11% per year while Wilson (2002 in Duncan and Clark, 2005) reported a 16% annual increase for the northwestern U.S. Risk maps of Montanan weeds indicate that large portions of

western areas of the state coul d be subject to invasion ( www.fs.fed.us/r1/cohesive_strategy/data/weeds/wra.ppt last accessed January 25,

2011 ). It was estimated by Wilson (2002 in Duncan and Clark, 2005) th at over 1.2 million acres within the United States are infested with hawkweed. Of that, 650,000 occurs in the northwestern United States (ID, MT, OR, WA). In British Columbia, both orange and meadow hawkweeds are widespread in southern and central portio ns of the province (E

- Flora BC Klinkenberg, 2010) and are of serious concern in northeastern British Columbia (Giroday and Baker, 2006). Information regarding hawkweed infestation within eastern United States is often unavailable, but several invasive

haw kweed species are widespread (see distribution maps below ).

Although hard data regarding the invasiveness of hawkweed in North America is difficult to obtain, existing data suggests a moderate to high invasive potential by these exotic hawkweed species. Risk analysis of orange and/or meadow hawkweed has been

conducted in Alaska and northeastern British Columbia and both indicate a moderate to a high degree of invasiveness (e.g. in Alaska both orange and meadow hawkweeds were rated 79 out of a possible 10 0 total points http://akweeds.uaa.alaska.edu/akweeds_ranking_page.htm last accessed January 25,

2011 ) (Carlson et al., 200 8 ; Giroday and Baker, 2006). A 2005

– 2006 USDA

- APHIS

PPQ Bioco ntrol Target Pest Canvassing and Evaluation survey of various Federal, tribal and state agencies, universities, and weed management districts ranked both orange and meadow hawkweeds as western region priority weeds for biological control, ranking seven out of 16 noxious weed species cited by land managers (Hansen and Bloem, 2006). Orange and/or meadow hawkweeds have been included on noxious weed lists in Alaska, Colorado, Idaho, Montana, Oregon, and Washington, and the Canadian provinces of Alberta, Britis h Columbia, and Quebec. Regulations vary by state/province but generally involve actions such as restricted importation and/or55

quarantine and prevention, containment, eradication, or other control measures. In some states such as Oregon and Montana, plan ts are ranked according to various criteria including detrimental effects, mode of spread or reproduction, distribution or potential distribution, and difficulty in control (Oregon Department of Agriculture, 2010; T. Moon (Montana Department of Agriculture ) pers. comm.). Invasive hawkweeds also have an adverse economic impact. Wilson (2002 in Duncan and Clark, 2005) estimated a $58.2 million dollar impact for the treatment of hawkweeds in

western United States.

Invasive hawkweeds have been proven detri mental in other areas of the world. From Europe, hawkweeds have spread to North America, New Zealand (Grundy, 1989), Australia (Syrett , pers. comm.), Japan (Suzuki and Narayama, 1977), Chile and Argentina (Norambuena, pers. comm.). In New Zealand

, 10 spec ies of hawkweeds infest over 1.25 million acres in the South Island alone (across 42% of the landmass) (McMillan, 1991), while other figures list 15 million acres infested in both islands with an economic impact of $42 million (New Zealand Dollars) (Sheean , 2009). In North America, invasive hawkweeds are primarily weeds of moist pastures and forest meadows, and mesic rangeland. The potential for spread in the northern Great Plains and the Columbia River region is difficult to predict at this time. However

, invasive hawkweed occurrences as weeds in the northeastern states during the last century, and their original distribution in northern and central Europe, suggest that they pose the greatest threat to cooler, sub

- humid to humid sites in the northern regi ons of the United States and Canada. Habitats most susceptible to invasion range from the lowlands of the northern Pacific Coast to elevations of 5,000 feet or more in the Intermountain States. Sites most vulnerable to invasion include roadsides, mountain meadows and clearings in forest zones, permanent pastures, hayfields, cleared timber units, and abandoned farmland where the soil is well drained, coarse textured, and moderately low in organic matter. Consequently, elk habitat, recreation areas, and pri stine mountain meadows in areas that have a climate similar to that of hawkweeds in their native range are particularly susceptible. None of the introduced hawkweed species are found in the natural grasslands or shrub

- steppe of the northern

Intermountain West, and are not expected to become problem weeds in any dry habitat usually associated with western rangelands, except where irrigated. Neither meadow nor orange hawkweed appears to survive in annually tilled cropland.

Most invasive hawkweeds are pere nnial, creeping stoloniferous plants that can displace native vegetation. Forage species in pastures and abandoned farmland are choked out by the advancing front of hawkweed. Hawkweeds threaten lawns and gardens, as well. Hawkweeds have been reported to have allelopathic effects on neighboring vegetation by exuding toxic chemicals into the soil (Dawes and Maravolo, 1973; Makepeace, 1976). These monocultures compete for soil moisture and nutrients, thereby posing risks to native species. As hawkweed mono cultures invade species

- rich range and mountain habitats, ecosystem functions and ecological relationships are affected. While no studies specifically address the effects of orange hawkweed on nutrient cycling and disturbance regimes, hawkweed’s ability t o dominate a community56

suggests that these species do affect habitat function. Hawkweeds generally negatively impact plant and animal diversity and there is serious concern about the loss of native plant biodiversity in infested areas. Ecological losses in plant and animal diversity can be enormous but cannot be economically calculated. Additional expenditures result from control costs. Hawkweeds are tenacious invaders, and once established, quickly develop into a patch that continues to expand until it covers the site with a solid mat of

rosettes.

Distribution maps of target Hieracium species in North America (USDA Plants Database, 2010).

Hieracium pilosella Hieracium auranticum

Hieracium flagellare Hieracium floribundum57

The invasion by hawkweeds may potentially contribute to the further decline of native bee populations, which are already being severely affected by ha bitat loss and pesticide

use. Nearly 70% of native bees are ground nesting ( http://www.xerces.org/wp

content/uploads/2008/11/nests_for_native_bees_fact_sheet_xerces_society.pdf ). These bees often nest in open, we ll drained soils, of which invasive hawkweeds readily invade. Because these invasive species form dense mats of vegetation (over 3,200/square meter) (Wilson et al., 1997), such infestations could limit the ability of

these bees to construct or maintain ne sts. Also a loss of biodiversity may occur with the introduction of invasive hawkweeds (Rose et al., 1995; Treskonova, 1991). This would result in less pollen and nectar sources for native bees and pollinators during the

course of the summer. The relian ce of herbicidal applications to mitigate hawkweed invasions may also have a detrimental impact on native pollinators by the short term loss of flora diversity of non

- target flowering forbs. Although native forbs (if initially present) may return after he rbicidal treatment, some current research being conducted at the University of Montana suggests that flowering of these native forbs may be negatively affected for several seasons until they have a chance to recover (Crone et al., 2009).

Meadow hawkwee d causes severe allergenic reactions. Reactions in people closely working with meadow hawkweed include minor skin rashes, sneezing, congestion and difficulty in breathing (Wilson, pers. comm.). Similar effects have not been reported in

animals. It is no t known what portion of the plant causes this allergenic reaction; although latex and other chemicals of closely related Asteraceae plants can cause dermatitis (Dawes et al., 1996). Based upon the rate of spread and potential ecological impacts of invasive hawkweeds,

the introduction of A. subterminalis , a host specific biological control agent with potentially negligible secondary impacts (see below), is warranted to help mitigate the impacts of these invasive weeds.

The second issue from the Fish and Wi ldlife commenter was in regards to possible

interactions of Aulacidea subterminalis and native hymenopteran species; in particular the potential for the introduction of dis ease

- causing pathogens through

A. subterminalis

.

Few studies have been conducted o n interactions between A. subterminalis and non

plant organisms in its native range so it is difficult to predict how the introduction of the gall wasp will impact non

- plant species, in this case native hymenopterans in North America. However, little impa ct is expected by the presence of A. subterminalis for the following reasons.

First, there will be few opportunities for direct interaction (i.e., displacement) of other

Aulacidea spp. wasps or other wasps in the insect family Cynipdae once A.

subterminal is is released in North America. Gall wasps of the genus Aulacidea are wide ranging in their distributions

, being found in both Holarctic (northern) and Nearctic (biogeographic region that includes the arctic and temperate areas of North58

America and Green land) regions. Aulacidea species native to the Nearctic region have been collected in the eastern half (Missouri eastward) of the United States and Canada

and none are associated with Hieracium ( Burks , 1979). Only two cynipid wasps have

been collected fr om Hieracium in North America; a stem infesting wasp on H. scouleri from Idaho) (L. Wilson (British Columbia Ministry Agriculture and Lands) and J. Littlefield (Montana State University), pers. comm.) that has not been identified, and an apparent introduce d species, Aulacidea hieracii , that has been recorded in the Province of Ontario infesting H. umbellatum (Silva and Shorthouse, 2006). These species do not occur on the same host plant as A. subterminalis nor in a niche occupied by A.

subterminalis . Thus, no interactions between A. subterminalis and native or other introduced cynipid wasps are expected.

It is possible that native parasitoids (i.e., mainly hymenopterans) will colonize A.

subterminalis and, through the gall wasp, have indirect negative eff ects on their native, gall

- forming host(s). Because any introduced A. subterminalis will be cleaned of any European parasitoids in quarantine before being released in North America, and that the parasitoid guilds of native and European Aulacidea are not s imilar to North American species little parasitism of the gall wasp is expected , and thus, potential indirect effects are not expected. In New Zealand, where A. subterminalis has been introduced and established for nearly 10 years, no parasitism has been observed (Paynter et al., 2010). No predators have been observed attacking A. subterminalis in the field in S witzerland, and no disease has appeared in the populations being reared in Switzerland, Montana, Canada, or New Zealand (G. Grosskopf

- Lachat (CABI Europe), Littlefield (Montana State University), L. Smith (Landcare, New Zealand), R. De Clerck

- Floate (Agriculture and Agri

- Foods Canada) per s . comm., Syrett et al. , 1998). Due to the short life of adult

A. subterminalis (up to a week under laboratory c onditions) and that the larvae feed within a gall in isolation from the general environment, horizontal transmission of pathogens by the wasp would be limited or rel atively non

- existent. More cryptic insect pathogens such as microsporidia ns or viruses are more likely to be transmitted vertically if present in A. subterminalis , and these pathogens are relatively specific to single species or closely related species (Solter and Maddox, 1998; Solter et al., 2000). Cynipids are distantly related to families t o which native bees belong (Ronquist, 1999; Sharkey, 2007; Whitfield, 1998). Therefore

, should there be any pathogens cryptically infesting A. subterminalis , they would be less likely to infect native bees (Superfamily: Apidoidae). There is no evidence to date that suggests any disease transmission from hymenopterans used for biological control of weeds or for insect pests to species of

bees. Reports of disease transmission in native bee populations indicate that closely related species were responsible f or possible transmission ( http://www.xerces.org/%20bumblebees/ last accessed January 25, 2011 ). For example Nosema bombi has been reported to have been transmitted to native Bombus spp. b ees by the int roduction of Bombus occidentalis and B. impatiens for pollination (although there appears to be some debate regarding this evidence http://www.scientificbeekeep ing.com/index.php?option=com_content&task=view&id=

84 last accessed January 25, 2011 ).59

As part of the quarantine process prior to the release of a biological control agent, insects are reared through a generation to eliminate any parasitoids or contam inating organisms. Laboratory rearing, along with close inspection of the reared insect colony for the incidence of either foreign parasitoids or disease

- causing pathogens, is an advised and reliable first line of defense for reducing the risk of introduc ing biotic contaminants with classical biocontrol agents (Goettel and Inglis, 2006)

. Aulacidea

subterminalis has only been collected in one location for rearing and release purposes (i.e. collected from the Black Forest (Germany), and has been reared for several generations as a pure colony at CABI

- Europe Switzerland Station, Delémont). Therefore, this population has a known and reliable history of having little parasitism and no disease problems.

References

–

Burks, B.D. 1979. Superfamily Cynipoide a. pp. 1045

– 1107. In: Krombein, K. V., P. D. Hurd, D. R. Smith, and B. D. Burks (eds.). Catalog of Hymenoptera North of Mexico. Vol. 1. Symphyta and Apocrita (Parasitica). Smithsonian University Press. Washington D.C.

Carlson, M. L., I. V. Lapina, M. Shep hard, J. S. Conn, R. Densmore, P. Spencer, J.

H eys, J. Riley, and J. Nielsen. 2008. Invasiveness Ranking System for Non

- Native Plants of Alaska. Forest Service, Alaska Region, R10

- TP

- 143.

Crone, E., M. Marler, and D. Person. 2009.Non

- target effects of bro adleaf herbicide on a native perennial forb: a demographic framework for assessing and minimizing impacts Journal of Applied Ecology. 46: 673

– 682

.

Dawes, D.S. and N.C. Maravolo. 1973. Isolation and characteristics of a possible allelopathic factor supporting the dominant role of Hieracium aurantiacum in the bracken grasslands of northern Wisconsin. Wisconsin Acad. of Sciences, Arts, and

Letters. 61: 235

– 252.

Dawes, R.S., C.M. Green, T.M. MacLeod and J. Ferguson. 1996. Daisy, dandelion and thistle contact allergy in the photosensitivity dermatitis and actinic reticuloid syndrome.

Contact dermatitis. 35: 109

– 110.

Duncan, C. L. and J. K. Clark, editors. 2005. Invasive Plants of Range and Wildlands and Their Environmental, Economic, and Societ al Impacts. Weed Science Society of America. 222 pp.

Giroday H. and V. Baker. 2006. Invasive Hawkweeds (Hieracium spp.) in Northeastern British Columbia. British Columbia Ministry of Forests and Range Range Branch, Invasive Plants Program, Prince George , BC. http://www.for.gov.bc.ca/hra/Publications/invasive_plants/HawkweeedRiskAssessment forNortheastBC_FINAL_24Oct06.pdf last ac cessed January 24, 2011.60

Goettel, M.S., and G.D. Inglis. 2006. Methods for assessment of contaminants of invertebrate biological control agents and associated risks. In: Bigler, F., Babendreier, D. and Kuhlmann, U. (eds.) Environmental Impact of Invertebr ates for Biological Control of Arthropods: Methods and Risk Assessment. CABI Publishing. Oxon, UK, pp. 145

– 165.

Grundy, T.P. 1989. An economic evaluation of biological control of Hieracium

. Research Report No. 202, Agribusiness and Economics Research U nit, Lincoln College, Canterbury, New Zealand, 41 p.

Hansen, R. , and K. Bloem. 2006. USDA

- APHIS

- PPQ Biocontrol Target Pest Canvassing and Evaluation 2005

– 2006 Final Report (November 2006).

Klinkenberg, B. (Editor) 2010. E

- Flora BC: Electronic Atlas of t he Plants of British Columbia [eflora.bc.ca]. Lab for Advanced Spatial Analysis, Department of Geography, University of British Columbia, Vancouver. (Consulted on 04 January 2011)

Makepeace, W. 1976. Allelopathy of mouse

- ear hawkweed. Proceedings of the 29th New Zealand Weed and Pest Conference, 106

– 109.

McMillan, G. 1991. Hawkweed report. J. of the New Zealand Mountain Lands Institute

48: 8

– 12 (In: Syrett, P., L.A. Smith, and G. Grosskopf. 1998. Introduction of

Aulacidea subterminalis (Hymenoptera: C ynipidae) into New Zealand for Biological

Control of Hieracium pilosella . Manaaki Whenua Landcare Research Contract Rep. LC9798/80, Lincoln, New Zealand).

Oregon Department of Agriculture. 2010. Oregon Department of Agriculture Noxious

Weed Control Polic y and Classification System 2010. 635 Capitol Street NE, Salem, Oregon 97301

- 2532. http://www.oregon.gov/ODA/PLANT/WEEDS

.

Paynter, Q., S. V. Fowler, A. H. Gourlay, R. Groenteman,P. G. Peterson, L. Smit h, and C. J. Winks. 2010. Predicting parasitoid accumulation on biological control agents of weeds. Journal of Applied Ecology. 47: 575

– 582.

Rice, P.M. 2010. INVADERS Database System (http://invader.dbs.umt.edu). Division of Biological Sciences, Universi ty of Montana, Missoula, MT 59812

- 4824. Ronquist, F. 1999. Phylogeny, classification and evolution of the Cynipoidea. Zoologica Scripta . 28: 139

- 164.

Rose, A.B., K. H. Platt, and C. Frampton. 1995. Vegetation change over 25 years in a

New Zealand short t ussock grassland: Effects of sheep grazing and exotic invasion. New Zealand Journal of Ecology. 19: 163

– 174.61

Sharkey, M.J. 2007. Phylogeny and Classification of Hymenoptera. Zootaxa . 1668:

521

– 548.

Sheean, F. 2009. Hawkweed could do more damage than ra bbits. Weeklytimes Now January 29, 2009. http://www.weeklytimesnow.com.au/article/2009/01/29/46955_latest

- news.html last

accessed January 24, 2011.

Silva, M.D. and J .D. Shorthouse. 2006. Comparison of the development of stem galls induced by Aulacidea hieracii (Hymenoptera: Cynipidae) on hawkweed and by Diplolepis spinosa (Hymenoptera: Cynipidae) on rose. Can. J. Bot. 84: 1052

– 1074.

Solter, L. F., and J. V. Maddox. 1998. Physiological host specificity of microsporidia as an indicator of ecological host specificity. J. Invertebr. Pathol. 71: 207

– 216.

Solter, L. F., D. K. Pilarska, and C. F. Vossbrinck. 2000. Host specificity of microsporidia pathogenic to forest L epidoptera. Biol. Control. 19: 48

– 56.

Suzuki, S. and T. Narayama. 1977. Orange hawkweed ( Hieracium aurantiacum L.) as an alien pasture weed in Hokkaido. Res. Bull. of the Hokkaido Natl. Agric. Expt. Stn.

117: 45

– 56. Syrett, P., L.A. Smith, and G. Gr osskopf. 1998. Introduction of Aulacidea

subterminalis (Hymenoptera: Cynipidae) into New Zealand for Biological Control of Hieracium pilosella . Manaaki Whenua Landcare Research Contract Rep. LC9798/80, Lincoln, New Zealand.

Treskonova, M. 1991. Changes in the structure of tall tussock grasslands and infestation by species of Hieracium in the Mackenzie country, New Zealand. New Zealand Journal of Ecology. 15: 65

– 78.

USDA, NRCS. 2010. The PLANTS Database (http://plants.usda.gov, 22 December 2010). Nation al Plant Data Center, Baton Rouge, LA 70874

- 4490 USA.

Whitfield, J.B. 1998. Phylogeny and evolution of host

- parasitoid interactions in Hymenoptera. Ann. Rev. Entomol. 43: 129

– 51.

Wilson, L. M. 2002. Report presented to Washington State Commission on pes ticide registration. University of Idaho, Moscow, ID. 1 pp.

Wilson, L. M., J. P. McCaffrey, P. C. Quimby, Jr. and J. L. Birdsall. 1997. Hawkweeds in the Northwestern United States. Rangelands. 19(4): 18

– 23.