Current Research
| Southern Pine Beetle Biological
Control |
| Significance: |
| Southern pine beetle remains the most serious insect
problem in southern forests. An operationally effective
and environmentally acceptable direct control treatment
for southern pine beetle is of highest priority for
southern forestry. All existing technologies for direct
control of SPB populations are either still in the experimental
stage or have problems that prohibit their use in some
situations. |
| Accomplishments: |
| We are testing a biological control program that integrates
available knowledge on SPB parasitoids and infestation
dynamics with a newly developed natural product, EliminadeTM,
that can be applied in SPB infestations to begin immediately
reducing SPB population levels. This technology is well
suited for application on commercial forests or private
lands, wilderness areas, or National Forests. It is
consistent with the principles of ecosystem management,
and should significantly reduce short and long term
losses from SPB. EliminadeTM is environmentally safe,
does not require EPA registration and could be made
immediately available to land managers. During the past
five years, in cooperation with Entopath Inc., we have
developed the synthetic food, and developed a prototype
technologies for field application in SPB infestations.
We have established that parasitoid longevity increases
when food and water are available, compared to water
only treatments. We have documented that egg resorption
decreases and development of new, immature eggs increases
with parasitoid feeding. The food appears nutritionally
complete, is partially rain-fast, and parasitoids will
feed on it when encountered in the field. We conducted,
in 1999 through 2001 in Alabama, operationally realistic
field tests, applying EliminadeTM by ground and air
to conserve and increase the effectiveness of parasitoid
populations as a means to stop or reduce SPB infestation
growth. This research was conducted in partnership with
L. E. Browne of Entopath, Inc. and in cooperation with
USDA Forest Service, National Forests of Alabama and
Forest Health Management of Pineville, MS. Epidemic
beetle populations resulted in unexpected movement of
SPB populations among treatment and control infestations,
but we still had limited success with the treatment.
We also gained new knowledge about the foraging behavior
of SPB parasitoid adults in the foliage of pine canopies.
We learned that application of food to foliage will
result in parasitoid feeding and subsequent movement
of those fed individuals to the bark of trees where
parasitoid oviposition occurs. |
| Importance: |
| This project may produce a direct control treatment
for SPB infestations that is environmentally acceptable
and consistent with the principles of ecosystem management.
An operationally effective and environmentally acceptable
direct control treatment for southern pine beetle is
of highest priority for southern forestry. This treatment
of SPB infestations will be particularly useful in sensitive
areas (wilderness, research natural areas, etc.). The
results of this project are likely to be used throughout
the entire range of SPB. This technology is well suited
for use by commercial, private and public timber managers.
We are developing a biological control program that
integrates available knowledge on SPB parasitoids and
infestation dynamics with a newly developed natural
product, EliminadeTM, that can be applied in SPB infestations
to begin immediately reducing SPB population levels.
In 2000 we gained new knowledge on SPB movement among
infestations and parasitoid foraging behavior in forest
canopies should result in being able to apply EliminadeTM
by aerial application. That would result in faster,
more cost effective treatments, which could be applied
to a greater number of infestations. This technology
is well suited for application on commercial forests
or private lands, wilderness areas, or National Forests.
It is consistent with the principles of ecosystem management,
and should significantly reduce short and long term
losses from SPB. EliminadeTM is environmentally safe,
does not require EPA registration and could be made
immediately available to land managers. |
| Publications |
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| Role and impact of Cerambycidae
in SPB population dynamics: |
| Significance: |
| Larvae of Cerambycidae are normally considered phytophagus,
feeding on most parts of living and dying plants and
trees. Conifer-inhabiting cerambycids often rapidly
colonize dying or dead trees attacked by pine bark beetles.
Release of pine host volatiles and a kairomonal response
to bark beetle pheromones, results in some cerambycids
arriving on host trees coincident with or shortly following
bark beetle attack, leading to spatial and temporal
coexistence of these two families in newly colonized
host tree phloem. Traditionally Monochamus have been
rarely looked at with other than casual interest, or
speculation that they may at time compete with SPB larvae.
If they play a more significant role than that in SPB
population dynamics, it is important to understand what
role they do play and how we can use that knowledge
to predict the future of SPB infestation growth and
decline. |
| Accomplishments: |
| Sampling of within tree populations of
Monochamus resulted in data that permitted construction
of partial life tables for Monochamus in loblolly pine.
That information showed high mortality during egg and
early larval stages suggesting an important role for
intraspecific competition or predation. Phloem sandwiches
with Monochamus larvae and bark beetle larvae enabled
us to examine the behaviors that emerged following intra
and interspecific encounters. Through repeated studies
we were able to determine that larvae of Monochamus,
always considered a phytophagus phloem feeder, actually
are cannibalistic and predaceous when they encounter
other larvae. |
| Importance: |
| In the southern U.S., Monochamus populations are often
found associated with southern pine beetle killed trees.
Adult cerambycids that are present in SPB infestations
rapidly respond and colonize the freshly killed trees,
continually breeding and numerically increasing in these
bark beetle infestations. It now appears highly probable
that not only are they competitors with SPB, but also
facultative predators on SPB larvae in phloem of host
trees. It has been theorized that intraguild predation
can drastically reduce or eliminate local populations
of prey items. This may prove important in decline of
SPB populations following density-dependent intraguild
predation and competition by several generations of
Monochamus. Deciphering the key elements of this association
through further research may provide knowledge essential
for long term prediction of SPB population trends. |
| Publications |
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| SPBMODEL |
| Significance: |
| A central component of successful Forest IPM systems
is the ability to predict damage amounts and associated
loss. Ability to predict southern pine beetle population
growth and associated tree mortality has only been possible
since the development of our SPB model. For the model
to remain in the central arena of forest IPM efforts,
we must revise the code to reflect advances in computer
modeling and programming. Creating an object-oriented
version of the model that will be more easily revised
and which can be housed as a WWWeb based model appears
necessary. |
| Accomplishments: |
| In 1995 we completed restructuring our southern pine
beetle model to include a fully revised user-friendly
graphical interface, better incorporation of winter
biology and population dynamics data, and simulation
capability on year-around basis. However, web sites
not in existence then, now house SPB forest management
information and alternatives. In a cooperative relationship
developed with modelers and computer scientists at Virginia
Tech University we have begun to re-write model code
and develop of a web based model version. |
| Importance: |
| The model is frequently used by pest management personnel
in the USDA Forest Service to predict growth of southern
pine beetle infestations and associated amounts of tree
mortality, and to determine and justify their control
efforts on National Forest and Wilderness Areas across
the South. The development and effective implementation
of SPBMODEL has enabled forest pest managers to predict
beetle infestation growth and corresponding tree mortality
in pine forests across the South. The model permits
correct quantitative assessment of bark beetle-caused
damage and impact in environmentally sensitive areas
such as national forests, wilderness and high-use recreational
sites. This has resulted in reduced pesticide usage,
protection of endangered species, and minimization of
disruptive control practices in southern pine forests.
SPBMODEL has become an integral component of the U.
S. Forest Service's integrated pest management strategies
for southern pine beetle, and is now an essential component
of their environmental assessments of potential damage
from this pest. A revised, web based version of the
model will permit its continuation as a primary pest
management tool in forest IPM. |
| SPBMODEL (Bark Beetle Java Hog) |
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| Gypsy Moth |
| Significance: |
 Gypsy moth is one of the most serious exotic insect
pests of hardwood forests in North America. It has defoliated
millions of acres of oak and other susceptible tree
species across the northeastern United States since
its introduction in the late 1900’s. Attempts
at eradication have failed, except in situations where
limited populations have been found introduced to new
areas of the United States. Pesticides used for these
eradication projects can be lethal to non-target species
and may become central points of environmental concern
when used to eradicate populations of gypsy moth in
new areas of discovery. |
| Accomplishments: |
 In northern Ozark forests in early May of 1994 and
1995, >25,000 acres of forest land were aerial sprayed
with Bacillusthuringiensis in the course of an apparently
successful eradication of gypsy moth. We established
treatment and control plots on sprayed and non-sprayed
areas, and monitored, for 3 years, abundance of forest
canopy arthropods, structure of the breeding bird community
and breeding biology of Hooded Warbler. We presented
results of this research at an invited formal biodiversity
symposium in Brazil. |
| Importance: |
| Lepidoptera populations were dramatically reduced
following the spray, and remained low for several weeks
thereafter. Lepidoptera populations remained low in
May and early June of 1995 in the area that had been
sprayed in 1994, and a similar pattern was noted in
1996 in the area sprayed in 1995. Effects on bird populations
were not as significant as expected, but some effects
were noted. We are now in the final phases of research
to fully establish the recovery of Lepidoptera and bird
populations on the spray areas. |
| Publications |
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Research Links
SPBMODEL (Bark Beetle Java Hog)
Southern Pine Beetle Internet Control Center
 
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