USDA Forest Service:
1931. Airplane dusting forest for western hemlock looper control. Pacific and Grays Counties, Washington.
USDA Forest Service:
1931. Airplane dusting forest for western hemlock looper control. Pacific and Grays Counties, Washington.
USDA Forest Service:
1931. Airplane dusting forest for western hemlock looper control. Pacific and Grays Counties, Washington.
USDA Forest Service:
1931. Two airplanes dusting on Naselle area for forest for western hemlock looper control. Pacific and Grays Counties, Washington.
USDA Forest Service:
1931. Airplane dusting on Naselle area for forest for western hemlock looper control. Pacific and Grays Counties, Washington.
USDA Forest Service:
1945. Airplane spraying insecticide. Western hemlock looper control project. Clatsop County, Oregon.
USDA Forest Service:
1945. Airplane spraying insecticide. Western hemlock looper control project. Clatsop County, Oregon.
USDA Forest Service:
1945. Airplane spraying insecticide. Western hemlock looper control project. Clatsop County, Oregon.
USDA Forest Service:
1945. Demonstration spraying on hemlock looper project, Clatsop County, Oregon.
USDA Forest Service:
1945. Demonstration spraying on hemlock looper project, Clatsop County, Oregon.
USDA Forest Service:
1945. Loaded airplane over hemlock looper control area. Clatsop County, Oregon.
USDA Forest Service:
1945. Loaded airplane over hemlock looper control area. Clatsop County, Oregon.
USDA Forest Service:
1945. Loaded airplane over hemlock looper control area. Clatsop County, Oregon.
USDA Forest Service:
1945. Aerial application of DDT on a plantation of Jack pine badly infested with insects. Deerskin area, Eagle River Ranger District, Chequamegon-Nicolet National Forest, Wisconsin.
USDA Forest Service:
1947. DC-3 spraying DDT. Douglas-fir tussock moth control project in northern Idaho.
USDA Forest Service:
1947. Ford Trimotor spraying DDT. Douglas-fir tussock moth control project in northern Idaho.
USDA Forest Service:
1948. Aircraft for Spraying and Dusting. EC-2. Bureau of Entomology and Plant Quarantine. Agricultural Research Administration. USDA.
USDA Forest Service:
1948. Central Aircraft's Travelaire 4000 discharging DDT spray over budworm-infested forest. Western spruce budworm control project. Kinzua area, Oregon.
USDA Forest Service:
1948. Central Aircraft's Travelaire 4000 discharging DDT spray over budworm-infested forest. Western spruce budworm control project. Kinzua area, Oregon.
USDA Forest Service:
1948. Central Aircraft's Travelaire 4000 discharging DDT spray over budworm-infested forest. Western spruce budworm control project. Kinzua area, Oregon.
USDA Forest Service:
1948. Helicopter spraying. Spray is visible by refracted light. Western spruce budworm control project. Kinzua area, Oregon.
USDA Forest Service:
1948. Helicopter spraying (spray does not show). Western spruce budworm control project. Kinzua area, Oregon.
USDA Forest Service:
1948. Helicopter en-route with spray. Western spruce budworm control project. Kinzua area, Oregon.
USDA Forest Service:
1948. Helicopter en-route with spray. Western spruce budworm control project. Kinzua area, Oregon.
USDA Forest Service:
1948. Helicopter spraying; spray is visible by refracted light. Western spruce budworm control project. Kinzua area, Oregon.
USDA Forest Service:
1949. B-18 spraying on western spruce budworm project. Mt. Hood area, Oregon.
USDA Forest Service:
1949. BT-19 releasing spray on western spruce budworm control project. Mt. Hood area, Oregon.
USDA Forest Service:
1949. B-18 spraying DDT. Spruce budworm control project. Mt. Hood area, Oregon.
USDA Forest Service:
1949. B-18 spraying DDT. Spruce budworm control project. Mt. Hood area, Oregon.
USDA Forest Service:
1949. B-18 spraying DDT. Spruce budworm control project. Mt. Hood area, Oregon.
