30 Keen, F.P. 1931. Letter dated July 17 to F.C. Craighead. On file with: Pacific Northwest Research Station, Forestry and Range Sciences Laboratory, 1401 Gekeler Lane. La Grande, Oregon 97850.
31 Craighead, F.C. 1931. Letter dated Sept. 2 to F.P. Keen. On file with: Pacific Northwest Research Station, Forestry and Range Sciences Laboratory, 1401 Gekeler Lane, La Grande, Oregon 97850.
32 Keen, F.P. 1931. Letter dated Sept. 9 to F.C. Craighead. On file with: Pacific Northwest Research Station, Forestry and Range Sciences Laboratory, 1401 Gekeler Lane, La Grande, Oregon 97850.
33 Craighead, F.C. 1931. Letter dated Sept. 21 to F.P. Keen. On file with: Pacific Northwest Research Station, Forestry and Range Sciences Laboratory, 1401 Gekeler Lane, La Grande, Oregon 97850.
34 Craighead, F.C. 1931. Letter dated Oct. 12 to F.P. Keen. On file with: Pacific Northwest Research Station, Forestry and Range Sciences Laboratory, 1401 Gekeler Lane, La Grande, Oregon 97850.
35 Keen, F. P. Jan. 25, 1932. Report of the mountain pine beetle situation in Crater Lake National Park and surrounding National Forest areas, season 1931 and recommendations for control, spring 1932. Portland, OR: U.S. Bureau of Entomology. 12 p. On file with: Pacific Northwest Research Station, Forestry and Range Sciences Laboratory, 1401 Gekeler Lane, La Grande, Oregon 97850.
36 Wickman, B.E. ; Hall, R.C. Oct. 27, 1953, Mountain pine beetle Conness Basin, Yosemite National Park, August 1953 appraisal survey. Berkeley, CA: U.S. Department of Agriculture, Bureau of Entomology and Plant Quarantine, Division of Forest Insect Investigations, Forest Insect Laboratory. 4 p. On file with: Pacific Northwest Research Station, Forestry and Range Sciences Laboratory, 1401 Gekeler Lane, La Grande, Oregon 97850.
37 Keen, F.P. 1932. Letters dated May and June to F.C. Craighead. On file with: Pacific Northwest Research Station, Forestry and Range Sciences Laboratory, 1401 Gekeler Lane, La Grande, Oregon 97850.
38 Craighead, F.C. 1932. Letter dated June 28 to F.P. Keen. On file with: Pacific Northwest Research Station, Forestry and Range Sciences Laboratory, 1401 Gekeler Lane, La Grande, Oregon 97850.
39 Keen, F.P. 1932. Letter dated Nov. 12 to F.C. Craighead. On file with: Pacific Northwest Research Station, Forestry and Range Sciences Laboratory, 1401 Gekeler Lane, La Grande, Oregon 97850.
40 Keen, F.P. Nov. 15, 1932. Report of the mountain pine beetle situation in Crater Lake National Park and adjacent National Forest lands, season 1932. Portland, OR: U.S. Bureau of Entomology. 6 p. On file with: Pacific Northwest Research Station, Forestry and Range Sciences Laboratory, 1401 Gekeler Lane, La Grande, Oregon 97850.
41 Solinsky, Frank J., III. Oct. 15, 1932. Report on the insect control project, spring 1932. U.S. Department of the Interior, National Park Service, Crater Lake National Park. 9 p. On file with: Pacific Northwest Research Station, Forestry and Range Sciences Laboratory, 1401 Gekeler Lane, La Grande, Oregon 97850.
42 Craighead F.C. 1932. Letter dated Nov. 29 to F.P. Keen. On file with: Pacific Northwest Research Station, Forestry and Range Sciences Laboratory. 1401 Gekeler Lane, La Grande, Oregon 97850.
43 Solinsky, Frank J., III. Aug. 1, 1933. Report on the insect control project, spring 1933, Crater Lake National Park. U.S. Department of the Interior, National Park Service, Crater Lake National Park. 12 p. On file with: Pacific Northwest Research Station, Forestry and Range Sciences Laboratory, 1401 Gekeler Lane, La Grande, Oregon 97850.
44 Solinsky, Frank J., III. 1933. Letters dated July and August to F.P. Keen. On file with: Pacific Northwest Research Station, Forestry and Range Sciences Laboratory, 1401 Gekeler Lane, La Grande, Oregon 97850.
