USDA Forest Service:
1920. Western pine beetle (Dendroctonus brevicomis) galleries in Pinus ponderosa. Sierra National Forest, California.
USDA Forest Service:
1923. Tree peeled to show galleries of western pine beetle. Photo also shows the method of tagging and numbering trees for control work. Southern Oregon Northern California (SONC) beetle control project.
USDA Forest Service:
1926. Dendroctonus brevicomis work on the surface of sapwood.
USDA Forest Service:
1926. Red turpentine beetle (Dendroctonus valens) work in ponderosa pine.
USDA Forest Service:
1926. Ponderosa pine tree attacked by Ips emarginatus. Southern Oregon Northern California beetle control project.
USDA Forest Service:
1926. Western pine beetle (Dendroctonus brevicomis) work on the surface of sapwood.
USDA Forest Service:
1926. Dendroctonus brevicomis work on the surface of sapwood.
USDA Forest Service:
c.1930. Platypus wilsoni egg tunnels in wood of Abies concolor.
USDA Forest Service:
1934. Three relative degrees of Dendroctonus brevicomis attack; heavy, medium, and light on ponderosa pine.
USDA Forest Service:
1934. Xyleborinus sp. galleries in sapwood of Douglas-fir killed by fire. Pack Forest, Washington.
USDA Forest Service:
1934. Xyleborinus sp. galleries in sapwood of Douglas-fir killed by fire. Pack Forest, Washington.
USDA Forest Service:
c.1934. Drawing shows primary egg gallery, larval mines, and pupal cells of Ips oregoni (Eich.) on surface of sapwood of pine.
USDA Forest Service:
c.1934. Drawing shows Ips radiatae Hopk. Egg gallery, larval mines and pupal cells on surface of sapwood of pine.
USDA Forest Service:
1934. Drawing by de Young shows the brood stages, work, and life history of the western pine beetle, Dendroctonus brevicomis Lec.
USDA Forest Service:
c.1934. Drawing shows some western bark beetles injurious to native and planted trees used for ornamental and recreational purposes.
USDA Forest Service:
1934. Drawing shows the brood stages, work and life history of the Douglas-fir beetle. Dendroctonus pseudotsugae Hopk. by artist de Young.
USDA Forest Service:
c.1934. Principle types of scolytid bark tunnels: cave tunnel, radiate, and forked. Transverse and longitudinal views.
USDA Forest Service:
1934. Types of ambrosia beetle galleries, pith and wood tunnels.
USDA Forest Service:
1934. Types of scolytid galleries, pith and wood tunnels.
USDA Forest Service:
1935. Western pine beetle (Dendroctonus brevicomis) adults and work in ponderosa pine (Pinus ponderosa).
USDA Forest Service:
1935. Western pine beetle (Dendroctonus brevicomis) adults and work in ponderosa pine (Pinus ponderosa).
USDA Forest Service:
1935. Page 3. BarkBeetle Enemies of California Forests. Prepared by the USDA Bureau of Entomology and Plant Quarantine in cooperation with the State Emergency Relief Administration - Project 3F-2-302 and the Emergency Educational Program. Berkeley, CA.
USDA Forest Service:
1935. Page 4. BarkBeetle Enemies of California Forests. Prepared by the USDA Bureau of Entomology and Plant Quarantine in cooperation with the State Emergency Relief Administration - Project 3F-2-302 and the Emergency Educational Program. Berkeley, CA.
USDA Forest Service:
1935. Orthotomicus orantus Sw. work in bark of Pinus ponderosa.
USDA Forest Service:
1953. Douglas-fir beetle (Dendroctonus pseudotsugae). Typical etching of log by galleries. Completeness of larval mines indicates a highly successful brood. North Fork Willamette River. Oakridge, Oregon.
USDA Forest Service:
1955. Pseudohylesinus grandis egg galleries and larvae on inner bark of silver fir. Baker River District, Mt. Baker National Forest. Washington.
USDA Forest Service:
1955. Pseudohylesinus grandis egg galleries on Pacific silver fir. Upper part - galleries on wood; lower part - galleries on bark, removed from upper part. Baker River District, Mt. Baker National Forest. Washington.
USDA Forest Service:
1955. Pseudohylesinus grandis egg galleries on wood of Pacific silver fir and mycelium of Armillaria mellea. Baker River District, Mt. Baker National Forest. Washington.
USDA Forest Service:
1956. Detail of Ips vancouveri egg gallery and larval mine on the wood surface of Pinus monticola.
USDA Forest Service:
1956. Ips concinnus egg galleries and larval mines on the inner bark surface of Sitka spruce.
