USDA Forest Service:
1902. Pioneer Forest Entomologists and Forest Pathologists. L-R: J.L. Webb, Asst. Forest Expert; Dr. Hermann VonSchrenk, in charge of Forest Pathology; Burns, Asst. in Forest Pathology; Dr. A.D. Hopkins, Forest Insect Investigations. Black Hills, SD.
USDA Forest Service:
1913. Example of tree surgery on valuable cultivated chestnut trees affected by the Chestnut Bark Disease. Westchester, Pennsylvania.
USDA Forest Service:
1934. The Bureau of Entomology and the Bureau of Plant Quarantine are consolidated with the disease control and eradication functions of the Bureau of Plant Industry to create the Bureau of Entomology and Plant Quarantine (BEPQ).
USDA Forest Service:
1935. George Englerth, forest pathologist, beside an insect cage on a fire-killed Douglas-fir near Gales Creek, Oregon.
USDA Forest Service:
1953. USDA is reorganized and the BEPQ, Division of Forest Insect Investigations and the BPISAE, Division of Forest Pathology are transferred to Research Branch of the Forest Service.
USDA Forest Service:
1953. Windthrow used for D. pseudotsugae population studies. Heavy Poria weirii infection in root over James Trappe's head. Packwood, Washington.
USDA Forest Service:
1954. Port Orford cedar dying from Phytophthora root infection. Phloeosinus filling in. North Bend, Oregon.
USDA Forest Service:
1955. Forest pathologists Drs. T.W. Childs and J. Clark (PNFRES) examine section from butt of 180 y.o. Douglas-fir infested with Poria weirii.
USDA Forest Service:
1956. Dr. E. Wright examines Douglas-fir laminated by Poria weirii. Weyerhaeuser Timber Company.
USDA Forest Service:
1957. Two large pole-sized western larch with heavy dwarf mistletoe. Notice large swellings on the boles. Gilbert Starks in tree examining the canker. Kootenai River above Libby, Montana.
USDA Forest Service:
1958. Dr. T.W. Childs examining ponderosa pine branch infested by the midge, Retinodiplosis sp. Canyon-Izee Road, Malheur National Forest, Oregon.
USDA Forest Service:
1959. Morey Vogel and Floyd Cory on plot location during dwarf mistletoe survey of the Growden Sale Area. Sherman Creek, Colville National Forest, Washington.
USDA Forest Service:
1960. Treating blister rust with Actidione. Control spray test at Oregon State University, Corvallis, Oregon.
USDA Forest Service:
1960. Kenneth J. Kessler identifying fungi that cause hard maple defects in the new laboratory at Rhinelander, Wisconsin.
USDA Forest Service:
1961. The transfer of survey and suppression-project entomologists and pathologists out of Research and into the Division of Timber Management created a staff called Insect and Disease Control - the equivalent of today's Forest Health Protection staff.
USDA Forest Service:
1961. William Brown staining material sectioned from canker on trembing aspen caused by Hypoxylon pruinatum. St. Paul, Minnesota.
USDA Forest Service:
1961. Dr. John Ohman examining a canker on a trembling aspen caused by Hypoxylon pruinatum. L 'Anse, Michigan.
USDA Forest Service:
1962. Roger Drayna removes the phloem from a white pine for a bioassay to determine if antibiotic treatment is present. Merrill, Wisconsin.
USDA Forest Service:
1962. Plant pathologist J.H. Ohman adjusting distillation apparatus. Northern Hardwoods Lab, Marquette, Michigan.
USDA Forest Service:
1963. Darroll Skilling working with single sporidia of white pine blister rust using a micromanipulator. Ramsey County, Minnesota.
USDA Forest Service:
1963. Ken J. Kessler, Jr., inoculating a root wound on sugar maple with a spore suspension of the fungus Ceratocystis coerulescens, the cause of the sapstreak disease. Upper Peninsula Experimental Forest, Michigan.
USDA Forest Service:
1963. Eugene Van Arsdel and Spar Sager examine Phomopsis canker on white pines. Schoolcraft County, Michigan.
USDA Forest Service:
1963. Fundamental research on pathogenic micro-organisms is aided by the use of the electron microscope. Corvallis, Oregon.
USDA Forest Service:
1964. John H. Ohman pointing to an open hole and seam. These are external indicators of butt rot. Upper Peninsula Experimental Forest, Michigan.
USDA Forest Service:
1964. Forest pathologist Ken J. Kessler, Jr., examining rot at the stump. Upper Peninsula Experimental Forest, Michigan.
USDA Forest Service:
1964. Plant pathologist Ken J. Kessler, Jr., working in the lab. Northern Hardwoods Laboratory, Marquette, Michigan.
USDA Forest Service:
1964. After all water is removed from plant material, it's ready for infiltration with melted paraffin. Plant pathologist Ken J. Kessler, Jr., is adding a piece of plant material to a small container of molten wax. Northern Hardwoods Lab, Marquette, MI.
USDA Forest Service:
1964. Ken J. Kessler, Jr., is cutting a ribbon of consecutive sections with the microtome. Northern Hardwoods Laboratory, Marquette, Michigan.
USDA Forest Service:
1964. After staining, plant pathologist Ken J. Kessler, Jr., applies a drop of canada balsam to the slide and then a thin glass cover slip. Northern Hardwoods Laboratory, Marquette, Michigan.
USDA Forest Service:
1964. Plant pathologist Ken J. Kessler, Jr., examines a finished slide under the microscope. Northern Hardwoods Laboratory, Marquette, Michigan.
