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**Proposed Release of Three Parasitoids for the Biological Control of
the Emerald Ash Borer (*Agrilus planipennis*) in the Continental United
States**

**Environmental Assessment, April 2, 2007**

Number range CHAPTER**Proposed Release of Three Parasitoids for the
Biological Control of the Emerald Ash Borer (*Agrilus planipennis*) in
the Continental United States**

**Environmental Assessment,**

**April 2007**

**Agency Contact:**

Juli Gould

United States Department of Agriculture

Plant Protection and Quarantine

Center for Plant Health Science and Technology

Otis Pest Survey, Detection, and Exclusion Laboratory

Building 1398

Otis ANGB, MA 02542-5008

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

**Table of Contents**

I.  Background and Introduction 3

II\. Purpose and Need for the Proposed Action 4

III\. Alternatives 5

IV\. Affected Environment 16

V. Environmental Consequences 18

VI\. Other Issues 35

VII\. Agencies, Organizations, and Individuals Consulted 35

VIII\. References 37

Appendix 1 43

Appendix 2 45

Number range CHAPTER**I. Background and Introduction**

The U.S. Department of Agriculture (USDA), Animal and Plant Health
Inspection Service (APHIS) and Forest Service (FS) are proposing to
release three insect parasitoid[^1] species for the biological control
(biocontrol) of the nonindigenous emerald ash borer (EAB) (*Agrilus
planipennis*). This environmental assessment[^2] (EA) has been prepared,
consistent with USDA, APHIS\' National Environmental Policy Act (NEPA)
implementing procedures (Title 7 of the Code of Federal Regulations
(CFR), part 372). It examines the potential effects on the quality of
the human environment that may be associated with the release of these
biocontrol agents to control infestations of EAB within the continental
United States. This EA considers the potential effects of the proposed
action and its alternatives, including no action.

The EAB is an invasive wood-boring beetle from Asia threatening North
America's ash trees (*Fraxinus* spp.). It was introduced into the
Detroit, Michigan, area, probably sometime in the 1990s, and was
identified as the cause of ash mortality in the area in 2002 (Haack et
al., 2002). EAB larvae feed on ash phloem, cutting off the movement of
resources within the tree and killing the tree in 4-5 years. EAB is now
considered established in natural ecosystems throughout the lower
peninsula of Michigan and contiguous areas of Ohio, Indiana, and
Ontario, Canada. Separate infestations are also found in the upper
peninsula of Michigan, Illinois, and Maryland. EAB appears well suited
for climatic conditions in North America and destroys entire stands of
ash. It is predicted that EAB will continue to disperse along various
continuous corridors of ash now present in natural and urban
environments due to the widespread use of ash as a landscape tree.

Number range CHAPTER**II. Purpose and Need for the Proposed Action**

APHIS and FS propose to release three parasitoids into the environment
of the continental United States for the purpose of reducing EAB
populations. These parasitoids are known to attack EAB consistently in
its native range in China. The biocontrol agents include one larval
ectoparasitoid, *Spathius agrili* (Hymenoptera: Braconidae) (Yang et
al., 2005), one species of egg parasitoid, *Oobius agrili* (Hymenoptera:
Encyrtidae) (Zhang et al., 2005), and one species of larval
endoparasitoid, *Tetrastichus planipennisi* (Hymenoptera: Eulophidae)
(Liu et al., 2003; Yang et al., 2006). Initial releases of each
parasitoid are planned for summer of 2007. Post-release monitoring,
including impacts on EAB and non-target wood-boring beetles and spread
and establishment of each parasitoid species, will be conducted.

There is a need to control EAB, an invasive wood-boring beetle that is
spreading rapidly and poses a serious threat to ash trees in the United
States if not controlled. Despite state and federal quarantines designed
to contain EAB, the lack of effective methods to detect EAB-infested
trees and the large size of the infestation has resulted in a shift by
regulatory agencies from a strategy of area-wide eradication to one
focused on eradication in outlying areas and containment in the core
infestation area (GAO, 2006). In the United States, EAB eradication
efforts involved the removal of all ash trees within a circle of
specified radius around known infestations (typically ½ mile). By the
time an infestation was discovered and treated, however, EAB had usually
already dispersed outside the eradication zone. The bronze birch borer,
*A. anxius* Gory, a native species closely related to EAB, is known to
spread at a rate of 10 to 20 miles per year, and this has been proposed
as an estimate for EAB's natural dispersal rate. Besides natural
dispersal, the spread of EAB has been accelerated through human-assisted
movement of infested ash firewood, timber, solid-wood packing materials,
and nursery stock. This resulted in the spread of EAB from Michigan to
Maryland and Virginia in 2003. As EAB spreads throughout North America,
regulatory agencies, land managers, and the public are seeking
sustainable management tools such as biological control to reduce EAB
population densities and to slow its spread (Cappaert et al., 2005; GAO,
2006; Poland and McCullough, 2006).

APHIS has responsibility for taking actions to exclude, eradicate,
and/or control plant pests, including EAB, under the Plant Protection
Act (7 United States Code (U.S.C.) 7701 *et seq.*). APHIS has been
delegated the authority to administer these statutes and has promulgated
Quarantines and Regulations (7 CFR 319) which regulate the importation
of commodities and means of conveyance to help protect against the
introduction and spread of harmful pests. The underlying strategy of the
proposed program is to reduce EAB population densities in infested areas
and slow its spread into to new areas.

**III. Alternatives**

APHIS considered two alternatives in response to the need to control EAB
and contain infestations: (1) no action and (2) biological control by
the release of the three parasitoids, *O. agrili, T. planipennisi,* and
*S. agrili* (the preferred action). Both alternatives are described
briefly in this section and the potential impacts of each are considered
in the following section.

**A. No Action**

Under the no action alternative, APHIS and FS would not release the
three parasitoids, *O. agrili, T. planipennisi,* and *S. agrili,* for
the management of EAB. APHIS, in cooperation with the appropriate State
Departments of Agriculture, would continue the current program that
includes survey, quarantine, and eradication of EAB in outlying areas
and containment in the core infestation area. Some control measures
could be taken by other Federal or non-Federal entities; those actions
would not be under APHIS' control or funded by APHIS. Local business
owners and area residents could attempt to control damage from EAB
infestations by removing the infested trees from their properties. The
lack of effective measures to prevent the spread of EAB from infested
areas (occurring via natural dispersal or artificial spread from
movement of infested ash products) will likely lead to an increase in
EAB populations, increase its range of distribution within the United
States, and further economic and environmental damage.

**Number range CHAPTERB. Biological Control Action (Preferred
Alternative)**

Under this alternative, APHIS and FS would release three parasitoids for
biocontrol of EAB. The biocontrol agents include one species of egg
parasitoid, *Oobius agrili* (Hymenoptera: Encyrtidae) (Zhang et al.,
2005), one species of larval endoparasitoid, *Tetrastichus planipennisi*
(Hymenoptera: Eulophidae) (Liu et al., 2003; Yang et al., 2006), and one
larval ectoparasitoid, *Spathius agrili* (Hymenoptera: Braconidae) (Yang
et al., 2005). Initial releases of each parasitoid are planned for the
summer of 2007. Releases of these EAB parasitoids are expected to reduce
the population of EAB and slow the spread rate in the United States.
This alternative would reduce but not eradicate EAB in the United
States. Measures that are occurring under the "no action" alternative
would likely continue even if the three parasitoids are released into
the environment; however, these biocontrol agents would serve as another
tool to assist in the protection of ash trees in North America.

**1) *Spathius agrili*:**

*Spathius agrili* is a gregarious larval ectoparasitoid; adult wasps lay
multiple eggs on e surface of EAB larvae after paralyzing the host EAB
during oviposition (egg laying) and stopping further development of the
host.

**Taxonomy:** *Spathius agrili* Yang (Hymenoptera: Braconidae). No
synonymy or common names.

**Methods used to identify *S. agrili.*** Yang et al. (2005) give a
detailed description of *S. agrili*. A key to *Spathius* of North
America was developed that includes information on how to separate
*Spathius agrili* from the native species (Marsh and Strazanac, in
press).

**Location of voucher specimens.** Insect Museum, Chinese Academy of
Forestry, Beijing, China; Nationaal Natuurhistorisch Museum, Leiden, the
Netherlands; U.S. National Natural History Museum, Washington, DC; and
West Virginia University Arthropod Collection, Morgantown, WV.

**Natural geographic range, other areas of introduction, and expected
attainable range in North America (also habitat preference and climatic
requirements of *S. agrili*).** *Spathius agrili* has been collected
from Tianjin, China and Changchun, Jilin Province, China. This species
is much easier to collect in Tianjin, which would be the likely source
of insects released in the United States. The climatic conditions that
are most conducive to population growth of *S. agrili* are not
explicitly known; therefore a climate matching analysis was conducted to
determine how similar Tianjin is to the upper Midwest. The climate
matching feature of the climate analysis software CLIMEX (Herne
Scientific Software Pty Ltd, Melbourne, Australia) was used. The model
calculated a Climate Match Index (CMI) that is a composite of six
variables: maximum temperature, minimum temperature, total rainfall,
rainfall pattern, relative humidity, and soil moisture. A CMI of 1
indicates an exact climate match. Because these insects do not live in
the soil, soil moisture was not included in the model. Adult *Spathius*
are only present in the summer, so the model was run for the adult stage
only for June through September, and because adults are free living
outside of the tree, relative humidity was included as a factor. For
larvae, which live under bark, relative humidity was not included in the
model, and the entire year was included.

For larvae, the CMI for Lansing MI, which is representative of locations
in the upper Midwest, was 0.63 (Figure 1) when comparisons were made
with Tianjin, China. CMI values were similar throughout the central part
of the United States (Figure 1). The CMI for adults was 0.60. Although
the CMI for adults was higher for Changchun (0.74) the value for larvae
was similar (0.66). This indicates that there is not a great advantage
to attempting to collect *S. agrili* from Changchun rather than Tianjin,
where collections are much easier to make. Although the climate in
Tianjin does not perfectly match that in the upper Midwest, it is
sufficiently similar that *S. agrili* could establish successfully.

**Figure 1:** Composite Match Index generated by CLIMEX climate software
showing the similarity in yearly climate between Tianjin, China and
North America for *S. agrili* larvae.

> ![](media/image3.wmf){width="3.626388888888889in" height="3.03125in"}

The cold hardiness of EAB and *S. agrili* were tested in the laboratory.
The super-cooling point of EAB was -22.36ºC, while that of *S. agrili*
was

-26.28 (Wu et al., in press), indicating that *S. agrili* should be able
to withstand cold temperatures in the more northerly range of EAB.

**Source of the culture/agent in nature (name of collector, name of
identifier).** Dr. Yang Zhong-qi collected the *Spathius* in Dagong,
Tianjin, China (38º56'N, 117 º29'E) and described it as a new species
(Yang et al., 2005).

**Life history (including dispersal capability and damage inflicted on
EAB).** *Spathius agrili* is well synchronized with its host, emerging
in the spring over 1½ months after adult EAB when third- and fourth-
instar EAB larvae are present. Females search the trunks of infested
trees, ovipositing on the EAB larvae through the bark. The EAB is
paralyzed and from 2-18 eggs are laid per larva. In the laboratory, a
female lays an average of 23 eggs during her lifetime, which averages 29
days. Because *S. agrili* females only seem to attack EAB larvae that
are feeding and close to the surface of the tree, fecundity in the lab
may be lower than in the field because of rearing methods. Sample
percentage parasitism in the field in China increases from August to
October from an average of 12% to an average of 42% (Yang et al., in
press). Although data are not available on the dispersal capability of
*S. agrili*, they fly strongly and are long lived, indicating that
dispersal capabilities may be high.

**Known host range of *S. agrili* based on valid literature records,
host data from museum specimens, and unpublished records.** This species
has not been collected or described from any other host. It was
described as a new species attacking EAB in 2005 (Yang et al., 2005). In
preparing his manuscript, Dr. Yang reviewed several collections of
Braconid wasps in China and Russia and conducted molecular analyses on
described species, comparing them to *S. agrili*, before concluding that
*S. agrili* was a previously undescribed species.

**History of past use of *S. agrili*.** *Spathius agrili* has never been
used as a biocontrol agent.

**Pathogens, parasites, hyperparasitoids of *S. agrili* and how to
eliminate them from a culture of the agent.** No pathogens, parasitoids,
or hyperparasitoids have been observed attacking *S. agrili*, either in
China or in specimens shipped to the United States. A small subset of
the parasitoids collected in China will be reared and identified by Dr.
Yang Zhong-qi, an expert on braconid parasitoids. This will ensure that
the established colony contains only *S. agrili* and no other braconids
or hyperparasitoids. Further observations will be made on parasitoids
emerging in quarantine in the United States. Only healthy *S. agrili*
will be used to establish a colony. Any diseased organisms will be sent
to insect pathologists for identification and hyperparasitoids will be
eliminated from the colony. Insects that are subsequently reared in the
United States will be maintained in pure culture and monitored for
disease.

**Other closely related genera, sibling species or closely-similar
species in North America.** The "Nomina Insecta Nearctica; a check list
of the insects of North America" (Poole, 1997) lists 25 species in the
genus *Spathius*. Some of these species are known to attack borers in
the genus *Agrilus*, and *Spathius floridanus* has been observed
attacking EAB larvae in Michigan at very low rates.

**2) *Oobius agrili:***

*Oobius agrili* is an egg parasitoid. Adult wasps lay an egg inside EAB
eggs, that are laid between bark layers and crevices on ash trunks and
branches. Larval wasps consume and kill host eggs to complete their
devlopment.

**Taxonomy:** *Oobius agrili* Zhang and Huang (Hymenoptera: Encyrtidae)
(Zhang et al., 2005). No synonymy or common names.

**Methods used to identify *Oobius agrili*.** *Oobius agrili* is
distinguished from the other *Oobius* spp. according to morphological
characteristics described by Zhang et al. (2005). Although no egg
parasitoids are known from EAB in Michigan (Bauer et al., 2005),
encyrtid parasitoids are reported from eggs of *Agrilus* *anxius*
including *Ablerus* sp., *Avetianella* sp., *Ooencyrtus* sp., and
*Thysanus* sp. (Nash et al., 1951; Barter, 1957; Loerch and Cameron,
1983).

**Location of voucher specimens.** Institute of Zoology, Chinese Academy
of Sciences, Beijing, China; U.S. National Natural History Museum,
Washington, D.C.; USDA Forest Service, Northern Research Station, E.
Lansing, MI; Entomology Museum, Michigan State University, E. Lansing,
MI; Museum of Zoology, Insect Division, University of Michigan, Ann
Arbor, MI.

**Natural geographic range, other areas of introduction, and expected
attainable range in North America (also habitat preference and climatic
requirements of *Oobius agrili*).** *Oobius agrili* was discovered in
2004 in the vicinity of Changchun in Jilin Province, China. This species
may have a wider distribution in China, however, no further exploration
for EAB egg parasitoids has been conducted in China due to limited
funding and the difficulty in finding EAB eggs. To estimate climatic
conditions conducive to establishment of *O. agrili* in North America,
Jilin Province was compared to North America using the climate matching
feature of the climate analysis software CLIMEX (Herne Scientific
Software Pty Ltd, Melbourne, Australia). Because these insects do not
live in the soil, soil moisture was not included in the model. Adult *O.
agrili* are only present in the summer, so the model was run for adults
only for June through September, and because adults are free living
outside of the tree, relative humidity was included as a factor.

For larvae, the CMI for Lansing MI, which is representative of all the
locations in the upper Midwest, was 0.66 (Figure 2) when comparisons
were made with Changchun in Jilin Province, China. CMI values were
similar throughout the central part of the United States (Figure 2).

**Figure 2.** Composite Match Index generated by CLIMEX showing the
similarity in yearly climate between Changchun, Jilin Province, China
and North America for *O. agrili* larvae.

![](media/image4.wmf){width="3.375in" height="2.8159722222222223in"}

**Source of the culture/agent in nature (name of collector, name of
identifier).** EAB eggs are collected near Changchun City (43º54\'N,
125º12\'E) in Jilin Province, China by Dr. Tonghai Zhao, Chinese Academy
of Forestry, Beijing and shipped from this area of China to Dr. Leah
Bauer's quarantine laboratory in E. Lansing, Michigan. The eggs are held
for up to 8 months until emergence of *O. agrili* is complete.

**EAB/ *Oobius agrili* interaction (e.g., parasitoid, pathogen,
parasite, competitor, antagonist, etc.)** *Oobius agrili* is a solitary
egg parasitoid. No entomopathogens or hyperparasitoids have been
discovered infecting or attacking *O. agrili* in shipments received from
China.

**Life history (including dispersal capability and damage inflicted on
EAB).** Based on data from field-collected eggs from China, *O. agrili*
spends the winter as mature larvae in EAB eggs and peak emergence occurs
when EAB begin ovipositing in mid-June, although some adults remain in
diapause until July and August. The sex ratio of *O. agrili* reared from
field-collected EAB eggs in China is 14.5:1 (female:male). *O. agrili*
is thelytokous parthenogenic (females produce females without mating).
Much of the knowledge of this parasitoid's biology is based on
laboratory studies performed at 25ºC with females held in a plastic cup
with a streak of honey, moist cotton ball, and EAB eggs laid on a small
ash twig. *Oobius agrili* females prefer to oviposit in 0- to 6-day-old
EAB eggs and live an average of 22.5 days. Their average lifetime
fecundity is approximately 24 progeny per female, and each generation
requires about three weeks (Table 1). Based on monthly field collections
in China during 2005, it was confirmed that *O. agrili* completes at
least two generations per year with parasitism reaching almost 62% in
August. These attributes of *O. agrili*, including female-biased sex
ratio, parthenogenesis (females produce females without mating), short
generation time, and high rates of parasitism and fecundity, are
characteristics of successful biocontrol agents (Kimberling, 2004). No
data are available on the dispersal capability of *O. agrili,* but
despite their small size (about 0.9 mm) they are relatively long-lived
(approximately three weeks) and are active jumpers and fliers in the
laboratory. Dispersal, however, may be facilitated by selecting release
sites with connecting corridors of ash, such as along riparian areas.
Moreover, since *O. agrili* reproduces through parthenogenesis,
dispersal is facilitated because females do not need to find a male and
mate before parasitism of EAB can occur.

**Table 1.** Biology of *O. agrili* in the laboratory reared in EAB eggs
at 25ºC (Bauer, 2007a).

  -------------------- ------------- ------------------ ------------------
  Stage                Egg-pupal     Adult              

                                     Female             Male

  Duration (d)         22.5 ± 2.1    13.6 ± 6.8         12.0 ± 0

  Fecundity            23.6 ± 11.4                      
  (parthenogenic)      (average)                        

                       62 (lifetime                     
                       maximum)                         

                       5 (daily                         
                       maximum)                         
  -------------------- ------------- ------------------ ------------------

**Known host organisms based on valid literature records, host data from
museum specimens, and unpublished records.** This egg parasitoid was
discovered in China in 2004. Specimens were sent to Drs. Zhang and
Huang, Chinese Academy of Science, Beijing, China for taxonomic
description as *Oobius agrili* (Zhang et al., 2005).

**History of past use of *Oobius agrili*.** *Oobius agrili* has never
been used as a biocontrol agent.

**Pathogens, parasites, hyperparasitoids of *Oobius agrili* and how to
eliminate them from a culture of the agent.** No pathogens, parasitoids,
or hyperparasitoids have been observed attacking *O. agrili*, either in
observations in China or in specimens shipped to the United States.
Insects used to establish colonies or to release in the field will be
allowed to emerge as adults in quarantine and only healthy,
unparasitized adults will be used.

**Other closely related genera, sibling species or closely-similar
species in North America.** There are eight described *Oobius* spp., all
from the Palearctic region and southern Africa. Of those, five species
parasitize eggs of the insect family Buprestidae (four are specific to
*Agrilus* spp.), one parasitizes a cerambycid, one is reported from eggs
of an asilid (which may be a case of mistaken identity), and the host is
unknown for the last species (Trjapitzin, 1963; 1989; Annecke, 1967;
Prinsloo, 1979; Zhang et al., 2005).

**3) *Tetrastichus planipennisi:***

*Tetrastichus planipennisi* is a larval endoparasitoid. Adults wasps lay
one or more eggs inside EAB larvae; larval wasps consume and kill host
larvae to complete their development.

**Taxonomy:** *Tetrastichus planipennisi* Yang (Hymenoptera:
Eulophidae). No synonymy or common names.

**Methods used to identify *T. planipennisi*.** *T. planipennisi* can be
distinguished from the other *Tetrastichus* spp. according to
morphological characteristics described by Yang et al. (2006). No
*Tetrastichus* spp. have been found parasitizing EAB in North America,
although other species parasitize *Agrilus* spp. in North America
including *T.* *rugglesi* Roh., which parasitizes bronze and red-necked
caneborers, *A. rubicola* Abeille and *A. ruficollis* (F.), in New York
(Mundinger, 1941) and an undescribed *Tetrastichus* sp. reared *A.
anxius* in Pennsylvania (Loerch and Cameron, 1983; UCD, 2006).
Additional species reported parasitizing *Agrilus* spp. in Europe
include *T. agrili* (Crawford, 1914), *T. agrilocidus* (Graham, 1991),
and *T. heeringi* (TSalbukov, 1983); and *T. jinzhouicus* in China
(Liao, 1987).

**Location of voucher specimens.** Institute of Zoology, Chinese Academy
of Sciences, Beijing, China; Insect Museum, Chinese Academy of Forestry,
Beijing, China; U.S. National Natural History Museum, Washington, D.C.;
USDA Forest Service, Northern Research Station, E. Lansing, MI;
Entomology Museum, Michigan State University, E. Lansing, MI; Museum of
Zoology, Insect Division, University of Michigan, Ann Arbor, MI;
Canadian National Collection of Insects, Agriculture and Agri-Food
Canada, Ottawa, Canada.

**Natural geographic range, other areas of introduction, and expected
attainable range in North America (also habitat preference and climatic
requirements of *T. planipennisi*).** *Tetrastichus planipennisi* was
discovered in 2003 in Jilin and Liaoning Provinces of China (Liu et al.,
2003) and later in Heilongjiang Province (Yang et al., 2006). This
species may have wider distribution in China, however, no further
exploration for EAB egg parasitoids have been done in China due to
limited funding for foreign exploration. To estimate climatic conditions
conducive to establishment of *T. planipennisi* in North America, Jilin
Province was compared to North America using the climate matching
feature of the climate analysis software CLIMEX (Herne Scientific
Software Pty Ltd, Melbourne, Australia). Because these insects do not
live in the soil, soil moisture was not included in the model. Adult *T.
planipennisi* are only present in the summer; for adults, the model was
run only for June through September, and because adults are free living
outside of the tree, relative humidity was included as a factor.

For larvae, the CMI for Lansing MI, which is representative of all the
locations in the upper Midwest, was 0.66 when comparisons were made with
Changchun in Jilin Province, China. CMI values were similar throughout
the central part of the United States (Figure 3).

**Figure 3.** Composite Match Index generated by CLIMEX showing the
similarity in yearly climate between Changchun, Jilin Province, China
and North America for *T. planipennisi* larvae.

![](media/image4.wmf){width="3.625in" height="3.0243055555555554in"}

**\
**

**Source of the culture/agent in nature (name of collector, name of
identifier).** EAB larvae parasitized by *T. planipennisi* were
collected near Changchun City (43º54\'N, 125º12\'E), Jilin Province,
China by Dr. Tonghai Zhao, Chinese Academy of Forestry, Beijing and
shipped to Dr. Leah Bauer's quarantine laboratory in E. Lansing,
Michigan. Mature parasitoid larvae can be held in chill (4ºC) for up to
4 months; *T. planipennisi* pupate and emerge as adults after
approximately two weeks at 25ºC.

**EAB/ *T. planipennisi* interaction (e.g., parasitoid, pathogen,
parasite, competitor, antagonist, etc.)** No entomopathogens or
hyperparasitoids have been discovered infecting or attacking *T.
planipennisi* in shipments received from China. The interactions between
*T. planipennisi* and EAB are close and host-specific because this type
of parasitoid is a koinobiont[^3], and evolved the means to overcome
physiological resistance mechanisms while it develops within its host's
body cavity. Interactions between *T. planipennisi* and EAB parasitoids
in North America will be minimal since few natural enemies attack EAB
here. In Michigan during 2003 and 2004, research on EAB natural enemies
demonstrated 0.7% EAB larval parasitism. The larval parasitoids reared
from almost 3,000 EAB larvae included three native parasitoids:
*Phasgonophora sulcata* (Hymenoptera: Chalcididae), *Spathius
floridanus* (Hymenoptera: Braconidae), *Atanycolus* sp. (Hymenoptera:
Braconidae), and one exotic ectoparasitoid, *Balcha* *indica*
(Hymenoptera: Eupelmidae). This parasitism rate for EAB in the United
States is low when compared to those reported in the literature for
native *Agrilus* spp. and for EAB in China (Liu et al., 2003; Yang et
al., 2005). Should *T. planipennisi* become introduced and established
in North American EAB populations, its impact on these incidental
parasitoids will be insignificant because their primary hosts attack
different host trees (Bauer et al., 2004; 2005).

**Life history (including dispersal capability and damage inflicted on
EAB).** *T. planipennisi* is a gregarious larval endoparasitoid; host
larvae continue feeding after parasitoid oviposition until external
symptoms of parasitism appear. Symptoms include bulges on the surface of
the host integument (outer covering of the body), causing the host
cadaver to look like a small braided rope. The larval parasitoids are
then mature and ready to exit the host cadaver during their wandering
phase just prior to pupation. Parasitized host larvae produce a range of
5 to 122 parasitoids, with an average of 35.2 parasitoid larvae per
host. *T. planipennisi* attack both third- and fourth-instar EAB larvae,
and overwinters as mature larvae in EAB galleries (Liu et al., in
press). In the spring, the parasitoid larvae form naked pupae, emerge as
adults, and chew a 1-mm diameter hole through the bark from which the
wasp brood exits the host gallery and tree.

In the laboratory, the egg-larval period for *T. planipennisi* is about
11 days and its pupal period is ca. 10 days (Table 2). Adult longevity
of females is around 24 days, almost twice that of males, and one
generation requires approximately three weeks. Their sex ratio is 3.5:1
(female:male), and average fecundity is 42 progeny/female. Adult
parasitoids are maintained with a streak of honey and moist cotton ball
during exposure to host larvae. Female parasitoids will not oviposit
unless host larvae are inserted in ash branches.

**Table 2.** The biology of *T. planipennisi* reared in the laboratory
at 25ºC (Bauer, 2007b).

  ------------- ------------ --------- ----------- ----------- -------------
  Stage         Egg-larval   Pupal                 Adult       

                             Female    Male        Female      Male

  Duration (d)  11.3 ± 4.2   10.3 ±    10.2 ± 2.3  23.6 ± 19.2 14.0 ± 10.3
                             1.5                               

  Sex ratio     3.5 : 1                                        
                (female :                                      
                male)                                          

  Fecundity     42.4 ± 4.5                                     
  ------------- ------------ --------- ----------- ----------- -------------

The biological attributes of *T. planipennisi*, including female-biased
sex ratio, short generation time, and high rates of parasitism and
reproduction, are characteristics of successful biocontrol agents
(Kimberling, 2004). No data are available on the dispersal capability of
*T. planipennisi,* but despite their small size adult females live more
than three weeks; both sexes are active jumpers and fliers in the
laboratory. Dispersal, however, may be facilitated by selecting release
sites with connecting corridors of ash, such as along riparian areas.

**Known host organisms based on valid literature records, host data from
museum specimens, and unpublished records.** This larval endoparasitoid
was discovered in China in 2003. Specimens were submitted to Drs. Zhang
and Huang, Chinese Academy of Science, Beijing, China for taxonomic
description. Drs. Yang and Wang, Chinese Academy of Forestry, Beijing,
China, eventually described this EAB parasitoid as *T. planipennisi*
(Yang et al., 2006).

**History of past use of *T. planipennisi*.** *Tetrastichus
planipennisi* has never been used as a biocontrol agent.

**Pathogens, parasites, hyperparasitoids of agent and how to eliminate
them from a culture of the agent.** No pathogens, parasitoids, or
hyperparasitoids have been observed attacking *T. planipennisi*, either
in observations in China or in specimens shipped to the United States.
Insects used to establish colonies or to release in the field will be
allowed to emerge as adults in quarantine and only healthy,
unparasitized adults will be used.

**Other closely related genera, sibling species or closely-similar
species in North America.** *Tetrastichus* is large and diverse genus
awaiting further taxonomic clarification. Several species in this genus
have been introduced as biocontrol agents of other invasive species
including *Tetrastichus asparagi* for the common asparagus beetle,
*Crioceris asparagi* (Coleoptera: Chrysomelidae) (Capinera and Lilly,
1975).

**IV. Affected Environment**

**A. North American *Agrilus* species**

The "Nomina Insecta Nearctica; a check list of the insects of North
America" (Poole, 1997) lists 164 species of *Agrilus* in North America
(see appendix 1). Most are not considered pests; however, Solomon (1995)
considers 24 *Agrilus* species to cause injury to trees and shrubs under
certain circumstances. Most species of *Agrilus* are unable to colonize
healthy trees; in fact, EAB is not considered a pest throughout its
native range. *Agrilus* species typically attack trees stressed by
factors such as drought, damage from other insects, or poor
silvicultural practices. Species such as *A. anxius* (bronze birch
borer) and *A. bilineatus* (Weber) (two-lined chestnut borer) are often
considered major pest species in forest and landscape situations, but
they are typically acting as secondary pests on already stressed trees
or trees not native to the United States. *Agrilus* species in North
America could potentially be at risk from attack by the three
parasitoids proposed for environmental release.

**B. Ash Resources of North America**

**Hosts of EAB**: The known hosts of EAB in the United States are ash
trees (*Fraxinus* spp.) including *F. americana* (white ash), *F. nigra*
(black ash), *F. pennsylvanica* (green ash), and some varieties of
horticultural ash. Twenty-two species of ash grow in the United States,
of which sixteen are native (USDA, NRCS, 2006). See appendix 2 for
distribution maps of native *Fraxinus* species in the United States.
There is increasing evidence that EAB will attack all *Fraxinus* spp.,
although innate susceptibility varies by species and variety (Liu et
al., 2003; Wie et al., 2004; Rebek et al., 2006; Liu et al., in press).
The FS estimates that 7,553,000,000 ash trees in United States
timberlands are potentially susceptible to EAB (USDA, FS, 2004).

Ash trees are present as ornamentals, street trees, or timber trees in
all of the lower 48 states. Each *Fraxinus* sp. is adapted to slightly
different habitats within forest ecosystems. Several species are
tolerant of poorly-drained sites and wet soils, protecting
environmentally-sensitive riparian areas; e.g. pure stands of black ash
grow in bogs and swamps in northern areas where they provide browse,
thermal cover, and protection for wildlife such as deer and moose. In
agricultural and shelterbelt areas, ash provides vital shelter for
livestock; e.g. ca. 25% of all trees in North Dakota are *Fraxinus* spp.
Bark of young ash trees is a favored food of mammals including beaver,
rabbit, and porcupines; older trees provide habitat for cavity-nesting
birds such as wood ducks, woodpeckers, chickadees, and nuthatches; seeds
are consumed by ducks, song and game birds, small mammals, and insects.

Ash timber is valued for applications requiring strong, hardwood, but
with less rigidity than maple. In the Eastern United States, a net
volume of 114 billion board feet of ash sawtimber is harvested,
comprising 7.5% of the volume of all hardwood species (FR, 2003). The
impact varies by state, but in Michigan alone an estimated 7.7 billion
board feet of ash timber is harvested annually. In 2001, ash accounted
for over 149 million board feet of timber products produced in the
United States. White ash is the primary commercial hardwood used in
production of tool handles, baseball bats, furniture, flooring,
containers, railroad cars and ties, canoe paddles, snowshoes, boats,
doors, and cabinets; green ash is used for both solid wood applications
such as crating, boxes, handles, and for fiber in the manufacture of
high grade paper; black ash is typically used for interior furniture,
cabinets (FR, 2003), and Northeastern Native Americans require ash for
the art of basketry.

Beyond manufacturing, ash trees play an important role in the urban
landscape due to their historical resistance to pests and tolerance of
adverse growing conditions, such as soil compaction and drought. Many of
the ash trees that now serve as street, shade, and landscape trees were
planted to replace elm trees destroyed by Dutch elm disease; ash trees
now comprise 5-20% of all street trees throughout North America. In the
United States, urban areas cover about 3.5% of the total land area,
contain more than 75% of the population, and support about 3.8 billion
trees. The City of Chicago has approximately 603,000 ash trees that
provide 14.4% of leaf area (FR, 2003). Trees are considered vital to the
health of cities because they sequester gaseous air pollutants and
particulate matter, help people conserve energy through the shade they
provide, assist in the dispersal of storm water, provide shelter belts
for urban fauna, and contribute aesthetic pleasure to the lives of
city-dwellers and tourists. Ash is a vital component of the urban
forest.

**V. Environmental Consequences**

**A. No Action Alternative**

EAB is an invasive wood-boring beetle that is spreading rapidly and
poses a serious threat to ash trees in the United States if not
controlled. Despite state and federal quarantines designed to contain
EAB, the lack of effective methods to detect EAB-infested trees and the
large size of the infestation has resulted in a shift by regulatory
agencies from a strategy of area-wide eradication to one focused on
eradication in outlying areas and containment in the core infestation
area (GAO, 2006). In the United States, EAB eradication efforts involved
the removal of all ash trees within a circle of specified radius around
known infestations (typically ½ mile). By the time an infestation was
discovered and treated, however, EAB had usually already dispersed
outside the eradication zone. The bronze birch borer, *A. anxius* Gory,
a native species closely related to EAB, is known to spread at a rate of
10 to 20 miles per year, and this has been proposed as an estimate for
EAB's natural dispersal rate (FR, 2003). Besides natural dispersal, the
spread of EAB has been accelerated through human-assisted movement of
infested ash firewood, timber, solid-wood packing materials, and nursery
stock. This resulted in the spread of EAB from Michigan to Maryland and
Virginia in 2003. As EAB spreads throughout North America, regulatory
agencies, land managers, and the public are seeking sustainable
management tools to reduce EAB population densities and to slow its
spread (Cappaert et al., 2005; GAO, 2006; Poland and McCullough, 2006).
Since its discovery, EAB has killed more than 20 million ash trees in
Michigan, Ohio and Indiana (MSU, 2007).

The potential path of expansion of the EAB infestation is through Ohio
and Indiana into the hardwood forests of the Northeast through
Pennsylvania and New York and into the Appalachian Mountain States
through Kentucky. In addition, spread of the pest through the Upper
Peninsula of Michigan to Wisconsin and through Ontario to New York is
possible. The economic impact would be severe if EAB spread from
currently infested areas into the forests of the northeastern United
States where nursery, landscaping, timber, recreation, and tourism
industries are economically critical.

Michigan implemented a moratorium on importing and selling ash nursery
stock in the Lower Peninsula of the State, impacting at least 9,519
nurseries (McPartlan et al., 2006). The State's 1,847 logging companies
and sawmills were also affected by their inability to receive ash logs
from the quarantined area (McPartlan et al., 2006). Additionally, more
than 2,500 private campgrounds in the tri-state area have been impacted;
many are losing business when campers are told that they cannot bring
firewood from quarantined areas (McPartlan et al., 2006). The area also
supports industries that utilize ash for tool handles, rail road ties
and pallet production.

The continued spread of this pest would threaten these resources and
permanently alter the Midwest's forest ecosystem that in some areas is
made up of 20 to 40 percent ash (McPartlan et al., 2006). In addition to
its value in forest ecosystems and for the timber industry, ash has
become an extremely popular urban/suburban landscape tree because of its
tolerance of less than ideal planting conditions and resistance to gypsy
moth and other pests. It is currently the most commonly planted tree in
new residential and commercial developments. Ash was planted widely in
Midwestern States to replace elms lost to Dutch elm disease, and it is
common in parks, public spaces, and neighborhoods across the United
States. The potential national impact of EAB on the urban environment
alone is 0.5 to 2 percent loss of total leaf area, or 30-90 million
trees with a loss of \$20-60 billion dollars (McPartlan et al., 2006).

The spread of EAB infestations could potentially have an enormous impact
on the U.S. nursery industry, municipal governments, and individual home
owners. As many as 300 million landscape ash trees have been planted in
Michigan alone. Removal and replacement costs would be staggering. In an
initial economic analysis of EAB, the USDA, FS estimated that EAB, if
not contained and eradicated, could cause approximately \$7 billion in
additional costs to state and local governments and landowners to remove
and replace dead and dying ash trees in urban and suburban areas over
the next 25 years (McPartlan et al., 2006). One city in Michigan
reported substantially higher water and electrical use because of the
loss of ash as shade trees (Victor Mastro, personal communication).

**B. Biological control alternative (preferred alternative)**

**1. Environmental and Economic Impacts of the Proposed Release of *S.
agrili***

**Known impact on vertebrates including humans:** *Spathius agrili* is
an obligate parasitoid of wood boring larvae, specifically the EAB. As
such, it will rarely come into contact with humans or other vertebrates,
and if it does, it is incapable of stinging or biting. Braconid wasps
have no known adverse impacts on humans or other vertebrates.

**Direct impact of *S. agrili* (e.g. intended effects on EAB, direct
effects on non-targets).** Percentage parasitism by *S. agrili* in China
can reach 30-50%, and in a few stands 85-90% of the EAB are parasitized
(Yang et al., 2005). Because *S. agrili* has three generations per year
compared with just one for EAB, generational percentage parasitism will
be greater than that measured during a single collection. *Spathius
agrili* clearly has the potential to cause considerable mortality to EAB
populations. In China, it is probable that EAB is not typically a pest
because of the interaction between host plant resistance and natural
enemies. While it is clear that American ash species are not resistant
to EAB per se, they can withstand some attack as evidenced by callusing
of EAB galleries (Gould, 2007). In China, where *F. pennsylvanica*
(native to North America) was attacked by EAB, parasitism by *O. agrili*
and *T. planipennisi* reduced EAB populations by 74% and the trees
continued to produce fruit. *Spathius agrili* will not have to cause
100% mortality of EAB to impact the health of ash stands, because ash
can successfully withstand some attack (Gould, 2007).

To evaluate the effects of *S. agrili* on non-target insect species,
no-choice host specificity tests were conducted in China and the United
States to determine the physiological host range of *S. agrili* and
possible direct effects on non-target species. In 2003-2005, potential
host larvae were collected in the ash forest where *S. agrili* was
attacking EAB in Tianjin, China to determine whether *S. agrili* would
attack other species in the same forest habitat. All species tested were
boring insects, including some that were closely related to EAB and
others that were not.

*Spathius agrili* finds hosts to parasitize by hearing sounds or feeling
vibrations produced by feeding larvae. Studies have shown that they do
not attack prepupae or molting larvae that are not feeding. All test
larvae, therefore, had to be feeding inside their natural hosts during
testing. To accomplish this, 1-1.5 cm diameter twigs were split
longitudinally and a 3 cm long groove was cut through to the bark on one
side. The test larvae were placed in these chambers, and the twigs were
reassembled and secured with rubber bands. The ends of the twigs were
sealed with paraffin wax to prevent desiccation. The twigs were placed
into 11.5 by 2.8 cm diameter glass vials that contained a newly eclosed
mated *S. agrili* female. The parasitoids were fed honey streaked on the
side of the vial. In tests in the United States, the larvae were checked
weekly for the presence of *S. agrili* eggs or larvae until the
parasitoid females died. In China the twigs were only checked after the
female died. All parasitized larvae were held to determine if *S.
agrili* could develop to the adult stage.

In the early host specificity tests, *S. agrili* did not parasitize wood
boring Lepidoptera, a longhorned beetle (Cerambycidae), or the one
*Agrilus* species tested (Table 3). Of the three species whose larvae
attack ash, only EAB was parasitized. Further testing was, therefore,
confined to members of the genus *Agrilus*, which might be at risk
because they are closely related to EAB. In the United States, the
two-lined chestnut borer, *A. bilineatus,* in oak, and the bronze birch
borer, *A. anxius*, in birch were tested. These species were chosen
because oak and birch can be found in close proximity to ash, they could
be collected in reasonable numbers for testing, and they are two
*Agrilus* species that sometimes occur in outbreak situations.

**Table 3.** No-choice host specificity testing from 2003-2005 in China
on boring larvae collected in the same ash plantation forest as *S.
agrili*. There was no attack on non-target species (Gould, 2007).

  -------------- -------------- --------------- ------- ------------ ----------
  Species        Order and      Host Plant used N       Percentage   Outcome
                 Family         in testing              Parasitism   

  *Agrilus       Coleoptera:    *Fraxinus       30      33%          Adults
  planipennis*   Buprestidae    velutina*                            produced

  *Agrilus       Coleoptera:    *Citrus         30      0%           No attack
  auriventris*   Buprestidae    reticulata*                          

  *Ostrinia      Lepidopera:    *Xanthium       30      0%           No attack
  orientalis*    Pyralidae      sibiricum*                           

  *Chilo         Lepidoptera:   *Phragmites     30      0%           No attack
  luteellus*     Pyralidae      communis*                            

  *Holcocerus    Lepidoptera:   *Fraxinus       30      0%           No attack
  insularis*     Cossidae       velutina*                            

  *Sylepta       Lepidoptera:   *Gossypiμm      30      0%           No attack
  derogata*      Pyralidae      herbaceμm*                           

  *Carposina     Lepidoptera:   *Zizyphus       30      0%           No attack
  niponensis*    Carposinidae   jujuba*                              

  *Thyestilla    Coleoptera:    *Abutilon       30      0%           No attack
  gebleri*       Cerambycidae   theophrasti*                         

  Pyralid larva  Lepidoptera:   *Fraxinus       30      0%           No attack
                 Pyralidae      velutina*                            
  -------------- -------------- --------------- ------- ------------ ----------

In China, *S. agrili* attacked *A. zanthoxylumi, A. mali,* and *A.
inamoenus*, but at rates that were lower than attack on EAB (Table 4).
Adult *Spathius* were produced on *A. mali*, and *S. agrili* developed
to the pupal stage on *A. inamoenus*, but mites attacked and killed the
pupae before adults could emerge. *Spathius agrili* developed through
the pupal stage on *A. zanthoxylumi,* but they seem to have entered
diapause and may emerge as adults in the spring. No attack occurred on
other *Agrilus* species, *Sphenoptera* sp. or *Eucryptorrhynchus
chinensis*.

*Spathius agrili* attacked some species of *Agrilus* other than EAB in
the no-choice tests, but attack rates were significantly lower than for
its primary host, the EAB (Table 4). Two out of thirty *A. bilineatus*
were attacked and both attacks resulted in cocoons but only two adult
males were reared from one egg cluster, and the other egg cluster
produced cocoons, but no adults emerged. However, this indicates that
*A. bilineatus* could serve as a potential host of *S. agrili.* No *S.
agrili* larvae survived on the single parasitized *A. anxius*.

**Table 4.** Host specificity testing in 2006 in China and the United
States. All species except *Eucryptorrhynchus* (weevil) are buprestid
beetles. Attack rate on all non-target species was significantly less
than the control

  -------------------- --------------- ------- -------------- ----------------
  Species              Host Plant used N       Percentage     Outcome
                       in testing              Parasitism     

  *Agrilus             *Fraxinus       30      27%            Adults produced
  planipennis* United  americana*                             
  States                                                      

  *Agrilus bilineatus* *Quercus alba*  30      7%             Adult males only

  *Agrilus anxius*     *Betula*        30      3%             No larval
                       *papyrifera*                           survival

  *Agrilus             *Fraxinus       23      65%            Adults produced
  planipennis* China   velutina*                              

  *Agrilus             *Zanthoxylum    31      32%            Cocoons produced
  zanthoxylumi*        bungeanum*                             -- too early for
                                                              adults

  *Agrilus mali*       *Malus          30      27%            Adults produced
                       micromalus*                            

  *Agrilus inamoenus*  *Citrus         15      7%             Cocoons produced
                       reticulata*                            but attacked by
                                                              mites

  *Agrilus sorocinus*  *Albizzia       15      0%             No attack
                       julibris*                              

  *Agrilus             *Juglans regia* 26      0%             No attack
  lewisiellus*                                                

  *Sphenoptera* sp.    *Artemisia      30      0%             No attack
                       ordosica*                              

  *Eucryptorrhynchus   *Ailanthus      5       0%             No attack
  chinensis*           altissima*                             
  -------------------- --------------- ------- -------------- ----------------

(EAB) (Fisher's Exact Test) (Gould, 2007).

No-choice tests determine the physiological host range of a parasitoid
by giving them no other option but to oviposit on a non-target host.
They are not allowed to accept or reject the host plant inhabited by
potential non-target hosts. To determine the ecological host range of
*S. agrili*, olfactometer tests were conducted in China to investigate
whether *S. agrili* is attracted to plant species harboring the larvae
tested in no-choice tests. Naïve mated *S. agrili* females were placed
in vertical y-tube olfactometers and given a choice of leaves and twigs
of various host plants or clean air. *Spathius agrili* was only
attracted to *F. pennsylvanica*, *F. velutina*, and *Salix babylonica*
(willow) (Table 5). The two *Fraxinus* species are native to the United
States. Even though some attack occurred on larvae found in *Citrus
reticulata, Malus micromalus*, and *Zanthoxylum bungeanum* in no-choice
tests, *S. agrili* females were not attracted to these tree species. In
nature, if parasitoids are not attracted to the host tree they are
unlikely to encounter and parasitize the non-target larvae. *Spathius
agrili* was attracted to willow leaves, and at least three *Agrilus*
species attack willow in the United States: *Agrilus pratensis
pratensis* (adults 4-6 mm long), *A. politus* (adults 5.0-8.5 mm long)
and *A. quadriguttatus* (size could not be found in literature). These
insects are quite small compared with adult EAB, which are 8.5-13.5 mm
long. *Spathius agrili* only attacks large EAB larvae, and *A.
pratensis* and *A. politus* undoubtedly are too small to be at risk of
attack. Even if *S. agrili* is attracted to willow in the United States,
it is unlikely to encounter suitable non-target hosts.

That some attack by *S. agrili* on non-target species occurred is not
totally surprising given that the native *S. floridanus* does attack EAB
in the United States. However, parasitism of EAB by this native
*Spathius* is extremely low, well below 0.5%, despite an abundance of
EAB. This low level of parasitism is certainly not sufficient to affect
EAB population growth or dynamics and it is not expected that *S.
agrili* will significantly impact populations of native *Agrilus*.

A fourth piece of evidence concerning host specificity was gathered in
China by collecting larvae of six *Agrilus* species and rearing them to
determine their parasitoid fauna. A total of 2,074 *Agrilus* larvae of
six species were collected and not a single *S. agrili* was recovered
(Table 6).

Given the combination of evidence from no-choice tests (lower parasitism
rates or no attack on non-target species), olfactometer tests (only
attracted to ash and willow), the lack of *S. agrili* reared from other
*Agrilus spp.* in China, and the fact that a native *Spathius* species
rarely attacks EAB, the release of *S. agrili* is not expected to have
adverse direct effects on non-target species.

**Table 5.** Response of *S. agrili* females to twigs and leaves of
trees that are hosts of *Agrilus* species tested in China. \* indicates
that *S. agrili* was

  ----------------- ---------- ------------- -------------------- -----------
  Tree species      Wasps      Wasps away    Potential insect     p value
                    towards    from stimulus host                 
                    stimulus                                      

  *F.               29         9             *A. planipennis*     0.0008\*
  pennsylvanica*                                                  

  *F. velutina*     27         8             *A. planipennis*     0.0003\*

  *Salix            23         12            *A. rotundicollis*,  0.0205\*
  babylonica*                                *A. viridis*,        
                                             *Meliboeus cerskyi*  

  *Citrus           15         16            *A. auriventris, A.  0.5000
  reticulata*                                inamoenus*           

  *Malus            19         17            *A. mali*            0.6911
  micromalus*                                                     

  *Zanthoxylum      23         15            *A. zanthoxylumi*    0.1279
  bungeanum*                                                      

  *Juglans regia*   14         22            *A. lewisiellus*     0.1215

  *Albizzia         18         18            *A. sorocinus*       0.4340
  julibrissin*                                                    

  *Pyrus            15         15            *Lampra limbata*     0.5722
  bretschneideri*                                                 

  *Prunus persica*  18         20            *Ptosima chinensis*  

  *Populus          18         17            *Melanophila picta,  0.6321
  deltoides*                                 Poecilonota          
                                             variolosa*           

  *Crataegus        14         18            *Caraebus* sp.       0.2983
  pinnatifida*                                                    

  *Euonymus         17         18            *A. nakanei*         0.5000
  japonica*                                                       

  *Ailanthus        10         23            *Eucryptorrhynchus   0.0175\*
  altissima*                                 brandti*             
  ----------------- ---------- ------------- -------------------- -----------

either significantly attracted to or repelled by the test stimulus
(Gould, 2007).

**Table 6.** Parasitoids emerging from *Agrilus* species collected in
China. No *S. agrili* were reared (Gould, 2007).

  ------------------ ------------------- -------------- ------------------
  *Agrilus* species  Collection Province Number larvae  Parasitoids
                                         collected      recovered

  *A. mali*          Shaanxi             427            *Tetrastichus* sp
                                                        and *Doryctes* sp.

                     Xinjiang            502            *Atanycolus* sp.
                                                        and *Eupelmus* sp

  *A. lewisiellus*   Shaanxi             227            *Tetrastichus* sp.

  *A. zanthoxylumi*  Shaanxi             515            *Tetrastichus* sp.
                                                        and Braconidae

  *A. sorocinus*     Tianjin             176            *Tetrastichus* sp.

  *A. auriventris*   Zhejiang            87             *Spathius* sp. not
                                                        *agrili*

  *A. inamoenus*     Hunan               140            No parasitoids
  ------------------ ------------------- -------------- ------------------

**2. Environmental and Economic Impacts of the Proposed Release of *O.
agrili***

**Known impact on vertebrates including humans:** *Oobius agrili* is a
very small (ca. 0.9 mm) obligate egg parasitoid of a wood boring insect,
specifically the emerald ash borer. As such, it will rarely come into
contact with humans or other vertebrates, and if it does, it is
incapable of stinging or biting. Encyrtid wasps have no known adverse
impacts on humans or other vertebrates.

**Direct impact of *Oobius agrili* (e.g. intended effects on targets,
direct effects on non-targets).** After discovery of *O. agrili* in
China in 2004, its effects on EAB populations were quantified by
sampling EAB eggs monthly from April through August in an infested ash
plantation in Jilin Province; samples in November 2005 were taken to
determine its overwintering stage (Liu et al., in press). Based on the
number of *O. agrili* adults successfully emerging from EAB eggs after
arrival in the FS quarantine laboratory in Michigan, parasitism rates
reached 56.3% parasitism in July and 61.5% in August (Figure 4). The
number of parasitoids reared from November collections vs. numbers
reared from spring collections suggests that overwintering mortality
does occur. Year-to-year variations in parasitism rates can be observed
by comparing parasitism rates from samples taken in June 2004 and those
taken June 2005. This variation may be caused by differences in the
overwintering survival of *O. agrili,* developmental rates EAB
populations, and other biotic/abiotic factors.

**Figure 4.** Parasitism (%) by *O. agrili* of field-collected EAB eggs
from Jilin Province, China in June 2004 (time of discovery) and during
seasonal sampling in 2005 (Bauer, 2007a).

![](media/image5.wmf){width="5.576388888888889in"
height="2.872916666666667in"}

To evaluate the direct effects of *O. agrili* on non-target insect
species, no-choice assays were performed in the laboratory using eggs of
six *Agrilus* spp., two cerambycids, and four lepidopterans (Table 7).
These insects were selected based on taxonomic similarity to EAB;
overlap in habitat and/or niche with EAB; risk to beneficial,
threatened, or endangered insects; feasibility of acquiring or rearing
enough eggs to perform and replicate reliable assays (Badendreier et
al., 2005).

**Table 7.** Oviposition by *O. agrili* females during no-choice assays
after exposure to 0- to 6-day old eggs of each species (Bauer, 2007a).

  ------------------ ------------------ ------------- ------------- ---------------
  **Order/Family**   **Species**        **Host**      **Egg size    **Oviposit?**
                                                      (mm)**        

  **Coleoptera**                                                     

  **Buprestidae**    *Agrilus           Ash           1.4 x 1.0     Yes
                     planipennis*                                   
                     (control)                                      

  ** **              *A. anxius*        Birch         1.3 x 0.7     Yes

  ** **              *A. bilineatus*    Oak           1.2 x 0.8     Yes

  ** **              *A. ruficollis*    Raspberry     1.1 x 0.7     Yes

  ** **              *A. cyanescens*    Oak           1.0 x 0.6     No

  ** **              *A. egenus*        Black locust  0.6 x 0.6     No

  ** **              *A. subcinctus*    Ash           0.6 x 0.4     No

  **Cerambycidae**   *Neoclytus         Ash           1.2 x 0.5     No
                     acuminatus*                                    

  ** **              *Megacyllene       Locust        2.4 x 1.0     No
                     robiniae*                                      

  **Lepidoptera**                                                   

  **Tortricidae**    *Choristoneura     Apple         0.5 x 0.5     No
                     rosaceana*                                     

  **Pieridae**       *Pieris rapae*     Cabbage       1.0 x 0.5     No

  **Bombycidae**     *Bombyx mori*      Mulberry      1.2 x 1.2     No

  **Sphingidae**     *Manduca sexta*    Tobacco       1.4 x 1.4     No
  ------------------ ------------------ ------------- ------------- ---------------

In no-choice assays, *O. agrili* did not oviposit in eggs of the
cerambycids and lepidopterans (Table 7). *O. agrili* may oviposit and
develop in *Agrilus* eggs from different species, but only those with
eggs similar in size to EAB eggs (Table 7). These included *A. anxius*
(bronze birch borer), *A. bilineatis* (two-lined chestnut borer), and
*A. ruficollis* (red-necked cane borer), which are considered aggressive
pests of birch, oak, and raspberry, respectively. Although many native
*Agrilus* spp. are considered destructive pests of forest and shade
trees, most prefer stressed, weakened, or dying trees.

Paired no-choice and choice assays were performed (Badendreier et al.,
2005) for two of the *Agrilus* spp. accepted by *O. agrili* during the
no-choice assays. The results of the choice assays demonstrate that *O.
agrili* shows a clear preference for EAB (*A. planipennis*) eggs over
those of *A. anxius* (Figure 5) and *A. ruficollis* (Figure 6).

**Figure 5.** Paired no-choice and choice assays to compare oviposition
(%±SD) rates of *O. agrili* on *A. anxius* eggs (Bauer, 2007a).

![](media/image6.wmf)

**Figure 6.** No-choice and choice assays to compare oviposition (%±SD)
rates of *O. agrili* on *A. ruficollis* eggs (Bauer 2007a).
![](media/image7.wmf){width="4.875196850393701in"
height="2.7015748031496063in"}

**3. Environmental and Economic Impacts of the Proposed Release of *T.
planipennisi.***

**Known impact on vertebrates including humans:** *Tetrastichus
planipennisi* is small (females 4-5 mm; males 2-3 mm) and gregarious
larval endoparasitoid of EAB. As such, it will rarely come into contact
with humans or other vertebrates, and if it does, it is incapable of
stinging or biting. Eulophid wasps have no known adverse impacts on
humans or other vertebrates.

**Direct impact of *T. planipennisi* (e.g. intended effects on EAB,
direct effects on non-targets).** After discovery of *T. planipennisi*
in China in 2003 (Liu et al., 2003), effects on EAB populations were
quantified by sampling EAB larvae monthly from April through August in
an infested ash plantation in Jilin Province; samples in November 2005
were taken to determine its overwintering stage (Liu et al., in press).
*T. planipennisi* completes four generations per year. In 2005,
parasitism averaged 22.4% and peaked at approximately 40% in August
(Figure 7). Year-to-year variations in parasitism rates can be observed
by comparing parasitism rates from samples taken in June 2004 and those
taken in June 2005. This variation may be caused by differences in the
overwintering survival of *T. planipennisi,* developmental rates of EAB
populations, and other environmental factors.

**Figure 7.** Seasonal abundance of *T. planipennisi* parasitizing *A.
planipennis* (EAB) larvae in Jilin Province, 2004-2005 (Bauer, 2007b;
Liu et al., in press).

![](media/image8.wmf){width="4.929861111111111in"
height="2.9694444444444446in"}

It was also found that third- and fourth-instar EAB larvae are available
as hosts throughout spring, summer, and fall for emerging *T.
planipennisi* adults, allowing for a rapid population build-up during
the summer (Liu et al., in press). Similar distributions in EAB larval
stages are observed in Michigan as populations increase throughout an
area (Cappaert et al., 2005).

To evaluate the direct effects of *T. planipennisi* on potential
non-target insect species, no-choice assays were performed in the
laboratory with larvae of EAB and eight species of buprestid (five
*Agrilus* and three *Chrysobothris*), five cerambycids, two
lepidopterans, and one hymenopteran (Table 8). These insects were
selected based on taxonomic similarity to EAB; overlap in habitat and/or
niche with EAB; risk to beneficial, threatened, or endangered insects;
feasibility of acquiring or rearing enough larvae to perform and
replicate reliable assays (Badendreier et al., 2005).

**Table 8.** Oviposition by *T. planipennisi* during no-choice assays
after exposure to last-instar larvae of the following species (Bauer,
2007b).

  ----------------- ------------------------ --------------- -------------
  Order/Family      Species                  Host            Accepted?

  Coleoptera                                                  

  Buprestidae       *Agrilus planipennis*    Ash             Control

                    *A. subcinctus*          Ash             No

                    *A. anxius*              Birch           No

                    *A. bilineatus*          Oak             No

                    *A. ruficollis*          Raspberry       No

                    *A. putillus*            Maple           No

                    *Chrysobothris femorata* Apple           No

                    *C. floricola*           Pine            No

                    *C. sexsignata*          Pine            No

  Cerambycidae      *Neoclytus acuminatus*   Ash             No

                    *Megacyllene robiniae*   Locust          No

                    *Astylopsis sexguttata*  Pine            No

                    *Monochamus scutellatus* Pine            No

                    Unknown                  Red Maple       No

  Tenebrionidae     *Tenebrio molitor*       Grains          No

  Lepidoptera                                                

  Pyralidae         *Galleria mellonella*    Beeswax         No

  Sphingidae        *Manduca sexta*          Solanaceae      No

  Hymenoptera                                                

  Cephidae          *Janus abbreviatus*      Willow          No
  ----------------- ------------------------ --------------- -------------

The results of the no-choice assays of *T. planipennisi* indicate that
this parasitoid is highly specific to EAB (Table 8), thus choice assays
were not performed.

**4. Effects on the Physical Environment and Indirect Effects of the
Release of the Three Parasitoids**

**Effects on physical environment (e.g. water, soil and air
resources):** Trees in the genus *Fraxinus* are important components of
many forested ecosystems throughout North America and are planted
extensively as urban and shelterbelt trees. USDA Forest Service Forest
Inventory and Analysis estimates that establishment of EAB throughout
the United States could result loss of approximately 2.6% of trees in
our timberlands, or 8 billion trees (USDA, FS, 2004). White, blue, and
Oregon ash grow on fertile uplands and river terraces; green, black,
Carolina, and pumpkin ash are wetland species; and velvet and
single-leaf ash grow in semi-deserts and canyons. If EAB populations are
not managed, ash resources throughout North America could be devastated
(MacFarlane and Meyer, 2005). The loss of ash over large geographical
areas will adversely affect water, soil, and air resources. Ash is an
important riparian tree and is often found along river banks. Removing
ash from stream banks will likely affect bank soil retention and stream
processes. The successful deployment of EAB biocontrol agents such as
*S. agrili, O. agrili,* and *T. planipennisi* will have a positive
impact on the physical environment by moderating EAB population
increase, thus limiting tree damage.

**Indirect effects (e.g. potential impacts on organisms that depend on
EAB or non-target species including potential competition with resident
biological control agents).** Successful management of EAB using
biological control agents, including *S. agrili, O. agrili,* and *T.
planipennisi,* will result in positive, indirect effects on U.S.
municipalities, land owners, wood industries, Native American basketry,
forest biodiversity, wildlife, riparian areas, and organisms dependent
on *Fraxinus* spp. (e.g. the cerambycid: red-headed ash borer,
*Neoclytus acuminatus;* the sphingid: great ash sphinx, *Sphinx cheri*;
the sesiids: ash clearwing, *Podesia syringae* and banded ash clearwing,
*P. aurecincta*; the scolytids: eastern, westren, and northern ash
beetles, *Hylesinus aculeatus, H. californicus,* and *H. criddlei*).

Indirect effects to ongoing biological control projects that utilize
*Agrilus* species to control weeds should also be considered. *Agrilus
hyperici* was released against Klamath weed in the western United States
with mixed results. In northern Idaho it is beneficial in assisting two
Klamath weed beetles, *Chrysolina* sp., in controlling the target weed
(Campbell and McCaffery, 1991), but in California it has been displaced
by *C. quadrigemina* (McCaffrey et al., 1995). *Agrilus hyperici* is a
root feeder acting on a rangeland weed. Another exotic buprestid,
*Sphenoptera jugoslavica*, also a root feeder, was released against
spotted, diffuse, and squarrose knapweeds. Based on the results of
research in the field in China and laboratory host specificity studies,
*S. agrili, O. agrili,* and *T. planipennisi* are host specific, and are
not expected to attack other buprestid species.

**5. Uncertainties Regarding the Environmental Release of *S. agrili, O.
agrili,* and *T. planipennisi.***

Once biological control agents such as *S. agrili, O. agrili,* and *T.
planipennisi* are released into the environment and become established,
there is a slight possibility they could move from the target insect
(EAB) to attack nontarget insects, such as native *Agrilus* species.
Native species that are closely related to the target species are the
most likely to be attacked (Louda *et al.*, 2003). If other insect
species were to be attacked by *S. agrili, O. agrili,* or *T.
planipennisi*, the resulting effects could be environmental impacts that
may not be easily reversed. Biological control agents such as *S.
agrili, O. agrili,* and *T. planipennisi* generally spread without
intervention by man. In principle, therefore, release of these
parasitoids at even one site should 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. Post-release
evaluations of *S. agrili, O. agrili,* and *T. planipennisi* populations
and their effects on EAB and other non-target species will be conducted
by APHIS and FS researchers.

In addition, these agents may not be successful in reducing EAB
populations in the continental United States. Approximately 12% of all
parasitoid introductions have led to significant sustained control of
the target pests, but the majority of introductions have failed to
provide control of the pest (Greathead and Greathead, 1992) either
because introduction did not lead to establishment or establishment did
not lead to control (Lane et al., 1999). Actual impacts on EAB
populations by *S. agrili, O. agrili,* and *T. planipennisi* will not be
known until after release occurs and post-release monitoring has been
conducted. The environmental consequences discussed under the "no
action" alternative may occur even with the implementation of the
biological control alternative, depending on the efficacy of those
agents to reduce EAB populations in the continental United States.

**6. Cumulative Impacts**

"Cumulative impacts are defined as the impact on the environment which
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 other actions" (40 CFR 1508.7).

Currently, no other biological control agents have been released against
EAB in the continental United States, although hundreds, if not
thousands of parasitoid species have been released in the United States
to attack various insect pests such as mealybugs, aphids, whiteflies,
and agriculturally important lepidopteran pests.

APHIS has put quarantines in place to prevent the movement of EAB out of
EAB-infested areas of the United States (7 CFR Subpart 301.53). This
area may expand as new infestations are discovered. Quarantines are put
in place to prevent the artificial spread of EAB through movement of
infested firewood or other infested wood materials.

APHIS, in cooperation with the appropriate State Departments of
Agriculture, conducts an EAB management program that includes survey for
EAB to determine new areas of infestation, and eradication of EAB by
cutting infested ash trees in outlying areas.

Release of the proposed parasitoids will have no negative cumulative
impacts in the continental United States because of the host specificity
of the parasitoids to EAB. Effective biocontrol of EAB will have
beneficial effects to current EAB management activities, and may result
in protection of ash resources and reduction in removals of infested
trees.

**7. Endangered Species Act**

Section 7 of the Endangered Species Act (ESA) and ESA's implementing
regulations require Federal agencies to ensure that their actions are
not likely to jeopardize the continued existence of federally listed
threatened endangered species or result in the destruction or adverse
modification of critical habitat.

A direct effect of the release of these parasitoids would be the
potential attack of eggs or larvae of federally listed insects,
resulting in additional declines of these species. In particular, the
valley elderberry longhorned borer (*Desmocerus californicus dimorphus*
Fisher) (Family Cerambycidae), a longhorned borer that mines the
interior wood of its host plant (Paine et al., 2004) could be perceived
to be at risk by these parasitoids.

During host specificity testing, *S. agrili* did not attack any
non-target species other than some *Agrilus* species. The larvae of the
valley elderberry longhorned beetle would not be accessible to the
relatively short ovipositor of *S. agrili*. In addition, this is not
closely related to EAB and would not likely be accepted as a host by *S.
agrili*. *Spathius agrili* must attack its hosts, even EAB, as they are
feeding inside of wood, so it is unlikely to attack any other threatened
or endangered insects, which are all external feeders.

During laboratory host-specificity testing, *O. agrili* rejected the
eggs of cerambycids tested: red-headed ash borer (*Neoclytus
acuminatus*) eggs on ash and locust borer (*Megacyllene robiniae*) on
black locust. The eggs of the valley elderberry longhorned borer are
about 2.5-3.0 mm long and are shaped like a football with longitudinal
ridges, whereas EAB eggs are ca. 1 mm in diameter and flat, oppressed
between bark layers or in bark crevices. Moreover, a closely related
encyrtid, *Avetienella longoi*, was released against the eucalyptus
longhorned borer, *Phoracantha semipunctata*, in California where no
impact on the valley elderberry longhorned beetles has been found. In
addition, *O. agrili* did not oviposit in eggs of Lepidoptera and
Coleoptera, other than *Agrilus* eggs of similar size to EAB.

During laboratory host-specificity testing, *T. planipennisi* rejected
larvae of five cerambycids tested: *Astylopsis sexguttata, Neoclytus
acuminatus*, *Megacyllene robiniae,* *Monochamus scutellatus,* and an
unknown species. Moreover, *T. planipennisi* did not oviposit in larvae
of any Lepidoptera, Coleoptera (other than EAB), or Hymenopteran tested.

Thus, due to the host specificity of the three parasitoids, their
release will have no effect on the wood boring Valley elderberry
longhorned beetle or its designated critical habitat.

There would be no effect on cave-dwelling or subterranean species
(Kretschmarr Cave mold beetle, Coffin Cave mold beetle, Comal Springs
dryopid beetle, Tooth Cave ground beetle, *Rhadine exilis, Rhadine
infernalis,* Helotes mold beetle); the American burying beetle where
eggs and larvae occur in soil and carcasses; aquatic species (Comal
Springs riffle beetle, Hungerford's crawling water beetle, Hine's
emerald dragonfly, Ash meadows naucorid); species that lay eggs in the
sand or soil (Northeastern beach tiger beetle, Delta green ground
beetle, Mount Hermon June beetle, Delhi Sands flower-loving fly, Zayante
band-winged grasshopper, Ohlone tiger beetle, Puritan tiger beetle, Salt
Creek tiger beetle). The eggs and larvae of these species occur in
habitats where these parasitoids would not occur. These parasitoids
would not be attracted to eggs and larvae in these habitats.

There would be no effect on butterfly, skipper, and moth species (Karner
blue butterfly, Bay checkerspot butterfly, Behren's silverspot
butterfly, Callippe silverspot butterfly, El Segundo blue butterfly,
Fender's blue butterfly, Lange's metalmark butterfly, Lotis blue
butterfly, Mission blue butterfly, Mitchell's satyr butterfly, Myrtle's
silverspot butterfly, Oregon silverspot butterfly, Palos Verdes blue
butterfly, Quino checkerspot butterfly, Saint Francis' satyr butterfly,
San Bruno elfin butterfly, Schaus swallowtail butterfly, Smith's blue
butterfly, Uncompahgre fritillary butterfly, Kern primrose sphinx moth,
Carson wandering skipper, Laguna Mountains skipper, Pawnee montane
skipper). From host specificity testing, no lepidopteran species were
accepted as hosts. In addition, these parasitoids are adapted to
attacking larvae and eggs of wood-boring species and would not be
attracted to eggs and larvae of non wood-boring species.

**VI. Other Issues**

Number range CHAPTERConsistent with Executive Order (EO) 12898, "Federal
Actions to Address Environmental 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 and low-income populations. The
environmental and human health effects from the proposed applications
are minimal and are not expected to have disproportionate adverse
effects to any minority or low-income populations.

Consistent with EO 13045, "Protection of Children From Environmental
Health Risks and Safety Risks," APHIS considered the potential for
disproportionately high and adverse environmental health and safety
risks to children. No circumstances that would trigger the need for
special environmental reviews are involved in implementing the preferred
alternative. Therefore, it is expected that no disproportionate effects
on children are anticipated as a consequence of implementing the
preferred alternative.

Number range CHAPTER**VII.** Number range CHAPTER**Agencies,
Organizations, and Individuals Consulted**

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

U.S. Department of Agriculture

Animal and Plant Health Inspection Service

Plant Protection and Quarantine

Otis Pest Survey, Detection, and Exclusion Laboratory

Building 1398

Otis ANGB, MA 02542-5008

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--1238

U.S. Department of Agriculture

U. S. Forest Service

Northern Research Station

1407 S. Harrison Rd.

East Lansing, MI 48823

U.S. Department of the Interior

Fish and Wildlife Service

4401 N. Fairfax Dr.

Arlington, VA 22203

**VIII. References**

Annecke, D.P. 1967. Three new southern African species of *Oobius*
Trjapitzin (Hymenoptera: Encyrtidae). Journal of Natural History.
1:319-325.

Badendreier, D., F. Bilger, and U. Kuhlmann. 2005. Methods to assess
non-target effects of invertebrate biological control agents of
arthropod pests. BioControl. 50:821-870.

Barter, G.W. 1957. Studies of the bronze birch borer, *Agrilus anxius*
Gory, in New Brunswick. Canadian Entomologist. 89:12-36.

Bauer, L.S. 2007a. Petition for Release of the Exotic Parasitoid *Oobius
agrili* for Biological Control of the Emerald Ash Borer, *Agrilus
planipennis*. Petition submitted to USDA, Animal and Plant Health
Inspection Service, Unpublished. 22 pp.

Bauer, L.S. 2007b. Petition for Release of the Exotic Parasitoid
*Tetrastichus planipennisi* for Biological Control of the Emerald Ash
Borer, *Agrilus planipennis* Petition submitted to USDA, Animal and
Plant Health Inspection Service, Unpublished. 22 pp.

Bauer, L.S., and H-P. Liu. 2005. Egg and larval parasitoids of EAB from
China: potential for biocontrol in North America. *In* Proceedings of
the Emerald Ash Borer Research and Technology Development Meeting,
Pittsburgh, PA. USDA Forest Service FHTET-2005-16, pp. 48-49.

Bauer, L.S., H-P Liu, R.A. Haack, T.R. Petrice, and D.L. Miller, 2004.
Emerald ash borer natural enemy surveys in Michigan and China. *In*
Proceedings of the Emerald Ash Borer Research and Technology Development
Meeting, Romulus, MI. USDA FS FHTET-2004-15, pp 71-72.

Campbell, C.L., and J.P. McCaffery. 1991. Population trends, seasonal
penology, and impact of *Chrysolina quadrigemina, C. hyperici*
(Coleoptera: Chrysomelidae), and *Agrilus hyperici* (Coleoptera:
Buprestidae) associated with *Hypericum perforatum* in northern Idaho.
Environmental Entomology. 20:303-315.

Capinera, J.L., and J.H. Lilly, 1975. *Tetrastichus asparagi*,
parasitoid of the asparagus beetle: some aspects of host-parasitoid
interaction. Annals of the Entomological Society of America. 58:595-596.

Cappaert, D., D. G. McCullough, T. M. Poland, and N. W. Siegert. 2005.
Emerald ash borer in North America: a research and regulatory challenge.
American Entomologist. 152-165.

Crawford, J.C. 1914. Some new Chalcidoidea. Insecutor Inscitiae
Menstruus. 2:180-182.

FR−see Federal Register

Federal Register. 2003. Emerald Ash Borer; Quarantine Regulations,
Interim Rule and Request for Comments. Animal and Plant Health
Inspection Service. Vol. 68, No. 198. October 14, 2003.

GAO−see Government Accounting Office

Gould, J. 2007. Petition for Release of an Exotic Parasitoid, *Spathius
agrili* Yang, for the Biological Control of the Emerald Ash Borer,
*Agrilus planipennis* Fairmaire. Petition submitted to USDA, Animal and
Plant Health Inspection Service, Unpublished. 22 pp.

Government Accounting Office. 2006. Invasive Forest Pests: Lessons
Learned from Three Recent Infestations May Aid in Managing Future
Efforts. <http://www.gao.gov/new.items/d06353.pdf>

Graham, M.W.R. 1991. A reclassification of the European Tetrastichinae
(Hymeoptera: Eulophidae): Revision of the remaining genera. Memoirs of
the American Entomological Institute, No. 49. 320 pp.

Greathead, D. and A.H. Greathead. 1992. Biological control of insect
pests by parasitoids and predators: the BIOCAT database. Biocontrol News
and Information. 13: 61N-68N.

Haack, R. A., E. Jendek, H-P Liu, T. Petrice, T.M. Poland, and H.Ye.
2002. The emerald ash borer: a new exotic pest in North America.
Michigan Entomological. Society Newsletter. 47:1-5.

Henry, D.B., and T.A. Bookhout. 1970. Utilization of woody plants by
beavers in northeastern Ohio. The Ohio Journal of Science. 70:123-127.

Kimberling, D.N. 2004. Lessons from history: predicting successes and
risks of intentional introductions for arthropod biological control.
Biological Invasions. 6:301-318.

Lane, S.D., N.J. Mills, and W.M. Getz, 1999. The effects of parasitoid
fecundity and host taxon on the biological control of insect pests: the
relationship between theory and data. Ecological Entomology. 24:
181-190.

Liao, D-X., X-L Li, X-F Pang, and T-L Chen. 1987. Hymenoptera:
Chalcidoidea (1) Economic Insect Fauna of China Fasc. 34 Science Press,
Beijing, 241 pp.

Liu, H-P, L.S. Bauer, L-W Song, Q-S Luan, S-H Sun, and R-Z Jin. In
Press. Seasonal abundance and population dynamics of *Agrilus
planipennis* (Coleoptera: Buprestidae) and its natural enemies *Oobius
agrili* (Hymenoptera: Encyrtidae) and *Tetrastichus planipennisi*
(Hymenoptera: Eulophidae) in China. Biological Control.

Liu, H-P, L.S. Bauer, R-T Gao, T-H Zhao, T.R. Petrice, and R.A. Haack.
2003. Exploratory survey for the emerald ash borer, *Agrilus
planipennis* (Coleoptera: Buprestidae), and its natural enemies in
China. Great Lakes Entomologist. 36:191-204.

Loerch, C.R., and E.A. Cameron. 1983. Natural enemies of immature stages
of the bronze birch borer, *Agrilus anxius* (Coleoptera: Buprestidae),
in Pennsylvania. Environmental Entomology. 12:1798-1801.

Louda, S.M., R.W. Pemberton, M.T. Johnson, and P.A. Follett. 2003.
Nontarget effects−The Achilles' Heel of biological control?
Retrospective analyses to reduce risk associated with biocontrol
introductions. Annual Review of Entomology. 48: 365-396.

MacFarlane, D. W. and S. P. Meyer. 2005. Characteristics and
distribution of potential ash tree hosts for emerald ash borer. Forest
Ecology and Management. 213:15-24.

Marsh, P.M. and J.S. Strazanac. In Press. A Taxonomic Review of the
genus *Spathius* Nees (Hymenoptera: Braconidae) and Implications for the
Biological Control of the Emerald Ash Borer.

McCaffrey, J.P., C.L. Campbell, and L.A. Andres. 1995. St. Johnswort.
pp. 281-285 *In* J.R. Nechols, L.A. Andres, J.W. Beardsley, R.D. Goeden,
and C.G. Jackson (eds.) Biological Control in the Western United States.
University of California Division of Agriculture and Natural Resources
Publication 3361.

McPartlan, D., P. Bell, and C. Kellogg. 2006. Eradication of Emerald Ash
Borer in Michigan, Ohio, and Indiana -- Implementation of the Strategic
Plan. January 11, 2006 revision \<
<http://www.aphis.usda.gov/plant_health/plant_pest_info/emerald_ash_b/downloads/strategicplan.pdf>\>
*last accessed* March 23, 2007.

Michigan State University. 2007. Emerald Ash Borer Information. \<
<http://www.emeraldashborer.info/>\> *last accessed* March 23, 2007.

MSU−see Michigan State University

Mundinger, F.G. 1941. Two buprestid cane-borers of brambles with
experiments on control. Journal of Economic Entomology. 34:532-537.

Nash, R.W., E.J. Duda, and N.H. Gray. 1951. Studies on extensive dying,
regeneration, and management of birch. Maine Forestry Service Bulletin
15. 82 pp.

Paine, T.D., J.G. Millar, and L.M. Hanks. 2004. Host preference testing
for parasitoids of a eucalyptus borer in California. *In.* R.G. Van
Driesche and R.Reardon (eds.) Assessing host ranges for parasitoids and
predators used for classical biological control: a guide to best
practices. pp. 138-142.

Poland, T. M., and D.G. McCullough. 2006. Emerald ash borer: invasion of
the urban forest and the threat to North America's ash resource. Journal
of Forestry. 118-124.

Poole, R.W. 1997. Nomina Insecta Neartica: a check list of insects of
North America. Nomina series volume 1. pp. 64-66.

Prinsloo, G.L. 1979. On some little known African Encyrtidae
(Hymenoptera: Chalcidoidea). Entomol. Mem. Dep. Agric. Rep. S. Afr.
60:1-35.

Rebek, E., D. Herms, D. Smitley, P. Bonello, and D. Cipollini. 2006.
Interspecific variation in ash resistance to emerald ash borer. p. 17,
*In* Proceedings of the 2005 Emerald Ash Borer Research and Technology
Development Meeting. FHTET-2005-16.

Solomon, J.D. 1995. Guide to insect borers of North American broadleaf
trees and shrubs. Agricultural Handbook 706. Washington, DC: U.S.
Department of Agriculture, Forest Service.

Trjapitzin, V.A. 1963. Species of the genus *Oobius* gen. n.
(Hymenoptera, Encyrtidae) in the USSR. Acta Entomol. Mus. Nat. Pragae.
35:543-547.

Trjapitzin, V.A. 1989. Parasitic hymenoptera of the Family Encyrtidae of
Palaearctics. Opredl. Faune USSR. 158:1-489.

TSalbukov, P. 1983. Relationships between *Agrilus cuprescens*, pest of
oil bearing rose, and *Tetrastichus heeringi*. Rastit. Zasht. Plant
Prot. 31:2-3.

UCD−see Universal Chalcidoidea Database

Universal Chalcidoidea Database. 2006.

<http://www.nhm.ac.uk/jdsml/research-curation/projects/chalcidoids/indexKeywords.dsml>
*last accessed* March 23, 2007.

USDA, FS−see USDA, Forest Service

USDA, Forest Service. 2004. Effects of urban forests and their
management on human health and environmental quality.
<http://www.fs.fed.us/ne/syracuse/Data/Nation/data_list_eab.htm> *last
accessed* March 23, 2007.

USDA, NRCS−see USDA, Natural Resources Conservation Service

USDA, Natural Resources Conservation Service. 2006. The PLANTS Database
(http://plants.usda.gov, 23 March 2007). National Plant Data Center,
Baton Rouge, LA 70874-4490 USA.

USDA, Natural Resources Conservation Service. 2003. Wetland Plantings
for Wildlife. Indiana Biology Technical Note No. 3. United States
Department of Agriculture. 7 pp.

Wie, X., D. Reardon, Y. Wu, J-H Sun. 2004. Emerald ash borer, *Agrilus
planipennis*, in China: a review and distribution survey. Acta
Entomologica Sinica 47: 679-685.

Wright, J., W. Rauscher, and H. Michael. 1990. *Fraxinus nigra* Marsh.
black ash. *In*: Burns, Russell M.; Honkala, Barbara H., (technical
coordinators). Silvics of North America: Vol. 2. Hardwoods. Agriculture
Handbook 654. Washington, DC: U.S. Department of Agriculture, Forest
Service. pp 344-347.

Wu, H., M-L Li, Z-Q Yang, and X-Y Yang. In Press. Research on cold
hardiness of emerald ash borer and it's two parasitoids, *Spathius
agrili* Yang (Hym., Braconidae) and *Tetrastichus planipennisi* Yang
(Hym., Eulophidae). Chinese Journal of Biological Control, 2007, 23(2):
In press.

Yang, Z-Q., J.S. Strazanac, Y-X Yao, and X-Y Wang. 2006. A new species
of emerald ash rer parasitoid from China belonging to the genus
*Tetrastichus* Haliday (Hymenoptera: Eulophidae) parasitizing emerald
ash borer from China. Proceedings of the Entomological Society of
Washington. 108:550-558.

Yang, Z-Q, J. S. Strazanac, P. M. Marsh, C. van Achterberg, and W-Y,
Choi. 2005. First recorded parasitoid from China of *Agrilus
planipennis:* A new species of *Spathius* (Hymenoptera: Braconidae,
Doryctinae). Annals of the Entomological Society of America.
98(5):636-642.

Yang, Z-Q, X-Y Wang, Y-N Zhang, G-J Liu, and E-S Liu. In press. Biology
of a new parasitic braconid, *Spathius agrili* Yang (Hymenoptera:
Braconidae) in China.

Zablotny, J.E. 2006. *Agrilus planipennis* Fairmaire Screening Aid.
<http://emeraldashborer.info/files/agriscrn.pdf>. USDA-APHIS-PPQ.

Zhang, Y-Z., D-W Huang, T-H Zhao, H-P Liu, and L.S. Bauer. 2005. Two new
egg parasitoids (Hymenoptera: Encyrtidae) of economic importance from
China. Phytoparasitica. 33:253-260.

**Appendix 1.** *Agrilus* species in North America (from Nearctica
Insecta Nomina (Poole, 1997)
<http://www.nearctica.com/nomina/beetle/colb-c.htm#anchor8802> *last
accessed* March 15, 2007)

**Agrilus Curtis 1825**

*Agrilus abditus* Horn 1891 (Agrilus)\
*Agrilus abductus* Horn 1891 (Agrilus)\
*Agrilus abjectus* Horn 1891 (Agrilus)\
*Agrilus abstersus* Horn 1891 (Agrilus)\
*Agrilus acaciae* Fisher 1928 (Agrilus)\
*Agrilus acutipennis* Mannerheim 1837(Agrilus)\
*Agrilus addendus* Crotch 1873 (Agrilus)\
*Agrilus aeneocephalus* Fisher 1928 (Agrilus)\
*Agrilus albocomus* Fisher 1928 (Agrilus)\
*Agrilus amelanchieri* Knull 1944 (Agrilus)\
*Agrilus angelicus* Horn 1891 (Agrilus)\
*Agrilus anxius* Gory 1841 (Agrilus)\
*Agrilus apachei* Knull 1938 (Agrilus)\
*Agrilus arbuti* Fisher 1928 (Agrilus)\
*Agrilus arcuata* Say 1825 (Buprestis)\
*Agrilus arizonicus* Obenberger 1936 (Agrilus)\
*Agrilus arizonus* Knull 1934 (Agrilus)\
*Agrilus atricornis* Fisher 1928 (Agrilus)\
*Agrilus audax* Horn 1891 (Agrilus)\
*Agrilus aureus* Chevrolat 1837 (Agrilus)\
*Agrilus aurichalceus* Redtenbacher 1849 (Agrilus)\
*Agrilus auroguttatus* Schaeffer 1905 (Agrilus)\
*Agrilus baboquivariae* Fisher 1928 (Agrilus)\
*Agrilus barberi* Fisher 1928 (Agrilus)\
*Agrilus benjamini* Fisher 1928 (Agrilus)\
*Agrilus bentseni* Knull 1954 (Agrilus)\
*Agrilus bilineata* Weber 1801 (Buprestis)\
*Agrilus blandus* Horn 1891 (Agrilus)\
*Agrilus burkei* Fisher 1917 (Agrilus)\
*Agrilus catalinae* Knull 1940 (Agrilus)\
*Agrilus cavatus* Chevrolat 1835 (Agrilus)\
*Agrilus cavifrons* Waterhouse 1889 (Agrilus)\
*Agrilus celti* Knull 1920 (Agrilus)\
*Agrilus cephalicus* LeConte 1860 (Agrilus)\
*Agrilus cercidii* Knull 1937 (Agrilus)\
*Agrilus champlaini* Frost 1912 (Agrilus)\
*Agrilus chiricahuae* Fisher 1928 (Agrilus)\
*Agrilus cladrastis* Knull 1945 (Agrilus)\
*Agrilus cliftoni* Knull 1941 (Agrilus)\
*Agrilus cochisei* Knull 1948 (Agrilus)\
*Agrilus concinnus* Horn 1891 (Agrilus)\
*Agrilus crataegi* Frost 1912 (Agrilus)\
*Agrilus criddlei* Frost 1920 (Agrilus)\
*Agrilus crinicornis* Horn 1891 (Agrilus)\
*Agrilus cupreomaculatus* Duges 1891 (Agrilus)\
*Agrilus cupreonitens* Fisher 1928 (Agrilus)\
*Agrilus cyanescens* Ratzeburg 1838 (Buprestis)\
*Agrilus davisi* Knull 1941 (Agrilus)\
*Agrilus defectus* LeConte 1860 (Agrilus)\
*Agrilus derasofasciatus* Boisduval and LeConte 1835 (Agrilus)\
*Agrilus difficilis* Gory 1841 (Agrilus)\
*Agrilus diospyroides* Knull 1942 (Agrilus)\
*Agrilus dolli* Schaeffer 1904 (Agrilus)\
*Agrilus dozieri* Fisher 1918 (Agrilus)\
*Agrilus duncani* Knull 1929 (Agrilus)\
*Agrilus egeniformis* Champlain and Knull 1923 (Agrilus)\
*Agrilus egenus* Gory 1841 (Agrilus)\
*Agrilus eleanorae* Fisher 1928 (Agrilus)\
*Agrilus esperanzae* Knull 1935 (Agrilus)\
*Agrilus exhuachucae* Knull 1937 (Agrilus)\
*Agrilus exiguellus* Fisher 1928 (Agrilus)\
*Agrilus exsapindi* Vogt 1949 (Agrilus)\
*Agrilus fallax* Say 1839 (Agrilus)\
*Agrilus falli* Fisher 1928 (Agrilus)\
*Agrilus felix* Horn 1891 (Agrilus)\
*Agrilus ferrisi* Dury 1908 (Agrilus)\
*Agrilus fisherellus* Obenberger 1936 (Agrilus)\
*Agrilus fisheriana* Knull 1930 (Agrilus)\
*Agrilus floridanus* Crotch 1873 (Agrilus)\
*Agrilus frisoni* Fisher 1943 (Agrilus)\
*Agrilus frosti* Knull 1920 (Agrilus)\
*Agrilus fulminans* Fisher 1928 (Agrilus)\
*Agrilus fuscipennis* Gory 1841 (Agrilus)\
*Agrilus geminata* Say 1823 (Buprestis)\
*Agrilus geronimoi* Knull 1950 (Agrilus)\
*Agrilus gibbicollis* Fall 1901 (Agrilus)\
*Agrilus gillespiensis* Knull 1947 (Agrilus)\
*Agrilus granulata* Say 1823 (Buprestis)\
*Agrilus hazardi* Knull 1966 (Agrilus)\
*Agrilus heterothecae* Knull 1972 (Agrilus)\
*Agrilus horni* Kerremans 1900 (Agrilus)\
*Agrilus howdeni* Knull 1957 (Agrilus)\
*Agrilus huachucae* Schaeffer 1905 (Agrilus)\
*Agrilus hualpaii* Knull 1939 (Agrilus)\
*Agrilus imbellis* Crotch 1873 (Agrilus)\
*Agrilus impexus* Horn 1891 (Agrilus)\
*Agrilus inhabilis* Kerremans 1900 (Agrilus)\
*Agrilus jacobinus* Horn 1891 (Agrilus)\
*Agrilus juglandis* Knull 1920 (Agrilus)\
*Agrilus lacustris* LeConte 1860 (Agrilus)\
*Agrilus lautuellus* Fisher 1928 (Agrilus)\
*Agrilus lecontei* Saunders 1871 (Agrilus)\
*Agrilus limpiae* Knull 1941 (Agrilus)\
*Agrilus liragus* Barter and Brown 1950 (Agrilus)\
*Agrilus macer* LeConte 1858 (Agrilus)\
*Agrilus malvastri* Fisher 1928 (Agrilus)\
*Agrilus masculinus* Horn 1891 (Agrilus)\
*Agrilus mimosae* Fisher 1928 (Agrilus)\
*Agrilus muticus* LeConte 1858 (Agrilus)\
*Agrilus neabditus* Knull 1935 (Agrilus)\
*Agrilus neoprosopidus* Knull 1938 (Agrilus)\
*Agrilus nevadensis* Horn 1891 (Agrilus)\
*Agrilus nigricans* Gory 1841 (Agrilus)\
*Agrilus niveiventris* Horn 1891 (Agrilus)\
*Agrilus oblongus* Fisher 1928 (Agrilus)\
*Agrilus obolinus* LeConte 1860 (Agrilus)\
*Agrilus obscurilineatus* Vogt 1949 (Agrilus)\
*Agrilus obsoletoguttatus* Gory 1841 (Agrilus)\
*Agrilus obtusus* Horn 1891 (Agrilus)\
*Agrilus ohioensis* Knull 1951 (Agrilus)\
*Agrilus olentangyi* Champlain and Knull 1925 (Agrilus)\
*Agrilus olivaceoniger* Fisher 1928 (Agrilus)\
*Agrilus ometauhtli* Fisher 1938 (Agrilus)\
*Agrilus ornatulus* Horn 1891 (Agrilus)\
*Agrilus osburni* Knull 1937 (Agrilus)\
*Agrilus otiosus* Say 1839 (Agrilus)\
*Agrilus palmacollis* Horn 1891 (Agrilus)\
*Agrilus palmerleei* Knull 1944 (Agrilus)\
*Agrilus parabductus* Knull 1954 (Agrilus)\
*Agrilus paracelti* Knull 1972 (Agrilus)\
*Agrilus paramasculinus* Champlain and Knull 1923 (Agrilus)\
*Agrilus parapubescens* Knull 1934 (Agrilus)\
*Agrilus parkeri* Knull 1935 (Agrilus)\
*Agrilus parvus* Saunders 1871 (Agrilus)\
*Agrilus pensus* Horn 1891 (Agrilus)\
*Agrilus pilosicollis* Fisher 1928 (Agrilus)\
*Agrilus politus* Say 1825 (Buprestis)\
*Agrilus prosopidis* Fisher 1928 (Agrilus)\
*Agrilus pseudocoryli* Fisher 1928 (Agrilus)\
*Agrilus pseudofallax* Frost 1923 (Agrilus)\
*Agrilus pubescens* Fisher 1928 (Agrilus)\
*Agrilus pubifrons* Fisher 1928 (Agrilus)\
*Agrilus pulchellus* Bland 1865 (Agrilus)\
*Agrilus puncticeps* LeConte 1860 (Agrilus)\
*Agrilus putillus* Say 1839 (Agrilus)\
*Agrilus quadriguttatus* Gory 1841 (Agrilus)\
*Agrilus quadriimpressus* Ziegler 1845 (Agrilus)\
*Agrilus quercicola* Fisher 1928 (Agrilus)\
*Agrilus quercus* Schaeffer 1905 (Agrilus)\
*Agrilus restrictus* Waterhouse 1889 (Agrilus)\
*Agrilus ruficollis* Fabricius 1787 (Buprestis)\
*Agrilus salviaphilos* Manley 1979 (Agrilus)\
*Agrilus santaritae* Knull 1937 (Agrilus)\
*Agrilus sapindi* Knull 1938 (Agrilus)\
*Agrilus sapindicola* Vogt 1949 (Agrilus)\
*Agrilus sayi* Saunders 1871 (Agrilus)\
*Agrilus scitulus* Horn 1891 (Agrilus)\
*Agrilus shoemakeri* Knull 1938 (Agrilus)\
*Agrilus sierrae* Van Dyke 1923 (Agrilus)\
*Agrilus sinuatus* Olivier 1790 (Buprestis)\
*Agrilus snowi* Fall 1905 (Agrilus)\
*Agrilus subcinctus* Gory 1841 (Agrilus)\
*Agrilus subtropicus* Schaeffer 1905 (Agrilus)\
*Agrilus townsendi* Fall 1907 (Agrilus)\
*Agrilus toxotes* Obenberger 1935 (Agrilus)\
*Agrilus transimpressus* Fall 1925 (Agrilus)\
*Agrilus utahensis* Westcott 1991 (Agrilus)\
*Agrilus ventralis* Horn 1891 (Agrilus)\
*Agrilus viridescens* Knull 1935 (Agrilus)\
*Agrilus viridis* Linnaeus 1758 (Buprestis)\
*Agrilus vittaticollis* Randall 1838 (Buprestis)\
*Agrilus walsinghami* Crotch 1873 (Agrilus)\
*Agrilus waltersi* Nelson 1985 (Agrilus)\
*Agrilus wenzeli* Knull 1934 (Agrilus)

**Appendix 2.** Distribution maps of *Fraxinus* species in the United
States.

(Maps from USGS, Earth Surface Processes, Digital Representations of
Tree Species Range Maps from "Atlas of United States Trees" by Elbert L.
Little and Other Publications \<
<http://esp.cr.usgs.gov/data/atlas/little/>\> *last accessed* March 21,
2007.)

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[^1]: In this case, small, stingless wasps that during their
    development, live in the body or egg of a single host individual,
    eventually killing that individual.

[^2]: ^2^ Regulations implementing the National Environmental Policy Act
    of 1969 (42

    United States Code 4321 *et seq.*) provide that an environmental
    assessment "\[shall include brief discussions of the need for the
    proposal, of alternatives as required by section 102(2)(E), of the
    environmental impacts of the proposed action and alternatives, and a
    listing of agencies and persons consulted." 40 CFR § 1508.9.

[^3]: