Biodegradable Insecticides in Forestry
177
• Significant, but not persistent, residual action.
• Previous experience in the field against the target insect.
• Registered or near registration for agricultural pests.
For a summary of the results of field tests against the major forest insect
pests, the review of the National Academy of Sciences is unsurpassed (NAS,
1975b). The report of the Committee for the Working Conference on Principles
of Protocols for Evaluating Chemicals in the Environment is an excellent reference on techniques and approaches to field testing (NAS, 1975c).
Concomitant formulation and application of Bacillus thuringiensis and
acephate for spruce budworm control (Morris, 1977) show great promise as a
new strategy for an early application to protect new current-year foliage. Acephate would be the controlling factor in the early instars with the bacteria promoting protection in the later instars after the acephate has degraded-usually
about 14 days.
Markin and Shea (1978), Brooks etal. (1978), and the USDA (l978b) have
prepared summaries of small and large field tests conducted for control of Douglas
fir tussock moth and western spruce budworm. Acephate is registered for use
against those two species. Other promising candidates are aminocarb (pending
establishment of a tolerance in western states), methomyl, permethrin, and trichlorfon (pending reestablishment of the old formulation that was available when
the field testing began) (Lyon, 1974). Carbaryl was registered with the EPA in
1978 for use against the western spruce budworm and Douglas fir tussock moth.
Morrison and Dimond (1978) have prepared a history and bibliography of field
trials for control of spruce budworm in Maine. Carbaryl (Sevin-4-0il), acephate,
and aminocarb are the most efficacious insecticides for spruce budworm management. Diftubenzuron is effective against the Douglas fir tussock moth, but
its efficacy toward spruce budworm is poor.
Larch casebearer [Coleophora laricella (Hubner)) is an important pest of
western larch. Malathion is registered to control this insect. Aerial applications
of acephate (Hard et al., 1977b; Washburn et al., 1977) were highly effective
at 1.0 lb/gal per acre and are not as variable as malathion. Chemical control
methods for larch casebearer may be set aside, if the recently developed biological
control methods are as effective as the early indications suggest (Bergstrom,
1978).
A compendium from the Douglas fir Tussock Moth Research and Development Program (Brooks et al., 1978) documents the findings of this major pestcontrol program. The integrated approach to R&D used by the program is an
example for forest insect pest-control research. At the onset ground spraying of
small plots indicated favorable results for trichlorfon, carbaryl, acephate (Markin,
1977; Brewer and Markin, 1978), diftubenzuron (Hard et al., 1977a, 1978), and
pyrethrins (stabilized). Aerial application over large plots showed that mexacarbate at 0.15 lb/acre was highly effective in suppressing the moth population
177
• Significant, but not persistent, residual action.
• Previous experience in the field against the target insect.
• Registered or near registration for agricultural pests.
For a summary of the results of field tests against the major forest insect
pests, the review of the National Academy of Sciences is unsurpassed (NAS,
1975b). The report of the Committee for the Working Conference on Principles
of Protocols for Evaluating Chemicals in the Environment is an excellent reference on techniques and approaches to field testing (NAS, 1975c).
Concomitant formulation and application of Bacillus thuringiensis and
acephate for spruce budworm control (Morris, 1977) show great promise as a
new strategy for an early application to protect new current-year foliage. Acephate would be the controlling factor in the early instars with the bacteria promoting protection in the later instars after the acephate has degraded-usually
about 14 days.
Markin and Shea (1978), Brooks etal. (1978), and the USDA (l978b) have
prepared summaries of small and large field tests conducted for control of Douglas
fir tussock moth and western spruce budworm. Acephate is registered for use
against those two species. Other promising candidates are aminocarb (pending
establishment of a tolerance in western states), methomyl, permethrin, and trichlorfon (pending reestablishment of the old formulation that was available when
the field testing began) (Lyon, 1974). Carbaryl was registered with the EPA in
1978 for use against the western spruce budworm and Douglas fir tussock moth.
Morrison and Dimond (1978) have prepared a history and bibliography of field
trials for control of spruce budworm in Maine. Carbaryl (Sevin-4-0il), acephate,
and aminocarb are the most efficacious insecticides for spruce budworm management. Diftubenzuron is effective against the Douglas fir tussock moth, but
its efficacy toward spruce budworm is poor.
Larch casebearer [Coleophora laricella (Hubner)) is an important pest of
western larch. Malathion is registered to control this insect. Aerial applications
of acephate (Hard et al., 1977b; Washburn et al., 1977) were highly effective
at 1.0 lb/gal per acre and are not as variable as malathion. Chemical control
methods for larch casebearer may be set aside, if the recently developed biological
control methods are as effective as the early indications suggest (Bergstrom,
1978).
A compendium from the Douglas fir Tussock Moth Research and Development Program (Brooks et al., 1978) documents the findings of this major pestcontrol program. The integrated approach to R&D used by the program is an
example for forest insect pest-control research. At the onset ground spraying of
small plots indicated favorable results for trichlorfon, carbaryl, acephate (Markin,
1977; Brewer and Markin, 1978), diftubenzuron (Hard et al., 1977a, 1978), and
pyrethrins (stabilized). Aerial application over large plots showed that mexacarbate at 0.15 lb/acre was highly effective in suppressing the moth population