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Priest River Experimental Forest

Scientist in Charge: 

General Description

Established in 1911, Priest River Experimental Forest is one of the first experimental forests set aside by the Forest Service as a forestry research center. Located just outside of Priest River, Idaho, this experimental forest is currently administered by the Rocky Mountain Research Station from the Forestry Sciences Laboratory in Moscow, Idaho.

Background Information and History

Image of map showing the location of the Priest River Experimental Forest
Location of the Priest River Experimental Forest
Priest River Experimental Forest (PREF) lies 13 miles northeast of the city of Priest River, Idaho, and 23 miles northwest of Sandpoint, Idaho. The Forest Service established the Priest River Experimental Forest in 1911 as one of the first experimental forests set aside as a forestry research center. PREF also served as the headquarters for the District 1 (now Region 1) investigative program until 1930, when PREF was incorporated into the Northern Rocky Mountain Forest and Range Experiment Station, headquartered in Missoula, Montana. The Rocky Mountain Research Station (RMRS), headquartered in Fort Collins, Colorado, currently administers the PREF from the Moscow Forestry Sciences Laboratory, Moscow, Idaho.

Situated on the westward slope of a spur of the Selkirk Mountains, PREF contains elevations that vary from 2,200 feet (671m) at the Priest River on the western boundary, to 5,900 feet (1,798 m) at Experimental Point, 5.6 miles (9 km) to the east. Mountains comprise approximately 90% of the area. This high land is cut by a number of streams that flow east to west, with ridges between them that also run in a general east-west direction. Though the main slopes face north and south, because tributary waterways also cut into ridges, a considerable number of slopes have east-west exposures. The slopes range from moderately steep to very steep. Benton Creek, Canyon Creek, and Fox Creek drain into Priest River, which cuts across the southwestern corner of the Experimental Forest.

PREF contains approximately 6,368 acres (2,758 ha) of mountainous forestland, with small areas of talus and alpine grassland. The Experimental Forest contains a variety of managed and reserve areas, a multitude of ecological site choices from wild to extremely disturbed areas, and all of the significant forest types and habitat associations of the region.

Within PREF are two Research Natural Areas, Canyon Creek, 977 acres (395 ha), established in 1937, and Wellner Cliffs, 310 acres (125 ha), established in 2006.


Sikkink, Pamela G. ; Jain, Terrie B. ; Reardon, James ; Heinsch, Faith Ann ; Keane II, Robert E. ; Butler, Bret W. ; Baggett, L. Scott. , 2017
Tinkham, Wade T. ; Denner, Robert J. ; Graham, Russell T. , 2015
Ferguson, Dennis E. ; Zack, Arthur C. , 2006
Harvey, Alan E. ; Jurgensen, Martin F. ; Larsen, Michael J. ; Graham, Russell T. , 1987
Ferguson, Dennis E. ; Stage, Albert R. ; Boyd, Raymond J. , 1986
Wykoff, William R. ; Crookston, Nicholas L. ; Stage, Albert R. , 1982
McDonald, Geral I. ; Hoff, Raymond J. ; Wykoff, William R. , 1981
Snyder, Gordon G. ; Haupt, Harold F. ; Belt, George H. Jr. , 1975
Brackebusch, Arthur P. , 1975
Rehfeldt, G. E. ; Steinhoff, R. J. , 1970
Satterlund, Donald R. ; Haupt, Harold F. , 1970
Haupt, Harold F. , 1969
Daubenmire, R. ; Daubenmire, Jean B. , 1968
Smith, Alexander H. ; Hesler, L. R. , 1968
Barney, Richard J. ; Fischer, William C. , 1967
Satterlund, Donald R. ; Haupt, Harold F. , 1967
Anderson, Hal E. ; Brackebusch, Arthur P. ; Mutch, Robert W. ; Rothermel, Richard C. , 1966
Doty, Robert D. ; Deitschman, Glenn H. , 1966
Breuer, Erwin H. , 1965
Smith, Alexander H. ; Theirs, Harry D. , 1964
Miller, Orson K. Jr. , 1964
Lloyd, Merle G. , 1963
Fahnestock, George R. ; Dieterich, John H. , 1962
Wellner, Charles A. , 1962
Fahnestock, George R. , 1960
Watt, Richard F. , 1960
Foiles, Marvin W. , 1959
Boyd, Raymond J. Jr. , 1959
Schaefer, Vincent J. ; Dieterich, John H. , 1959
Leaphart, Charles D. ; Copeland, Otis L. Jr. ; Graham, Donald P. , 1957
Wellner, C. A. ; Watt, R. F. ; Helmers, A. E. , 1951
Wellner, C. A. ; Watt, R. F. ; Helmers, A. E. , 1951
Haig, Irvine T. ; Davis, Kenneth P. ; Weidman, Robert H. , 1941
Davis, Kenneth P. ; Moss, Virgil D. , 1940
Davis, Kenneth P. ; Klehm, Karl A. , 1939
Kachin, T. ; Gisborne, H. T. , 1937
Hornby, L. G. , 1935
Haig, I. T. , 1932
Marshall, Robert ; Averill, Clarence. , 1928
Brewster, Donald R. ; Larsen, J. A. , 1925
Larsen, J. A. ; Lowdermilk, W. C. , 1924
Larsen, J. A. ; Smith, R. J. , 1913

Publications (Non RMRS)

Belt, G. H., J. G. King, and H. F. Haupt. 1975. Streamflow modification by a silicone antitranspirant. p. 201-206 in Proc. Symp. on Watershed Manage., Am. Soc. Civ. Eng. [Logan, Utah, Aug. 11–13, 1975.]

Brackebusch, A. P. 1960. The significance of Priest River slash research findings to the land manager. p. 4-6 in West. For. Conserv. Assoc., West. For. Fire Res. Counc. Proc.

Buchanan, T. S., G. M. Harvey, and D. S. Welch. 1951. Pole blight of western white pine: A numerical evaluation of the symptom. Phytopathology 41:199-208.

Callaham, Robert Z. 1962. Geographic variability in growth of forest trees. p. 311-325 in Tree growth. Theodore T. Kozlowski, ed. Ronald Press, New York.

Carpenter, Stanley B. 1961. The Weidman Arboretum. Priest River Experimental Forest 1931-1961. 9 p. Paper presented at Northwest Sci. Ann. Meet. [Dec. 27-28, 1961].

Cline, R. G., and B. L. Jeffers. 1975. Installation of neutron probe access tubes in stony and bouldery forest soils. Soil Sci. 120:71-72.

Copeland, Otis L., Jr. 1957. Ecological consideration of the pole blight disease. Fourth Int. West. Dis. Work Conf. Proc. 49-55.

Copeland, Otis L., Jr. 1958. Soil-site index studies of western white pine in the northern Rocky Mountain region. Soil Sci. Soc. Am. Proc. 22:268-269.

Davis, Kenneth P. 1936. Stand improvement measures for the western white pine type. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. mimeo rep. 62 p.

Davis, Kenneth P. 1938. Weedings and thinnings in the western white pine forests. South. Idaho For. 2(2):28-31.

Davis, Kenneth P. 1940. Economic aspects of managing western white pine forests. Northwest Sci. 14(2):26-32.

Ehrlich, John, and Loren K. Baker. 1942. Preliminary study of dying of young white pine on Coeur d'Alene and Kaniksu Forests. Spec. Rep., Univ. Idaho Sch. For. 50 p.

Fahnestock, George R. 1954. Cooperative logging slash research in the northern Rocky Mountains. Soc. Am. For. Proc. 1954:169-170.

Fahnestock, George R. 1954. Roofing slash fires can save--or lose--you dollars. Fire Control Notes 15(3):22-26.

Fitzgerald, O. A. 1951. Plague in the big pines. Popular Mech. 95(4):140-142, 244-246.

Fitzgerald, O. A. 1958. A man and his monument. Steelways 14(4):24.

Gilbertson, R. L., C. D. Leaphart, and F. D. Johnson. 1961. Field identification of roots of conifers in the Inland Empire. For. Sci. 7:352-356.

Gill, Lake S., Charles D. Leaphart, and Stuart R. Andrews. 1951. Preliminary results of inoculations with a species of Leptographium on western white pine. USDA, B.P.I.S.A.E., Div. For. Pathol., For. Pathol. Spec. Release 35. 14 p.

Gisborne, H. T. 1923. A million dollars a year for smoke. The Timberman 24(7):33-34.

Gisborne, H. T. 1924. Moisture content of fuels as an index of fire danger. Lumber World Rev. 45:44.

Gisborne, H. T. 1926. Forest fire--a mother of invention. Am. For. and For. Life 32(389):265.

Gisborne, H. T. 1926. Meteorology and forest fire prevention. p. 29 Univ. Mont., For. Kaimin.

Gisborne, H. T. 1927. The objectives of forest fire--weather research. J. For. 25(4):452-456.

Gisborne, H. T. 1929. The complicated controls of fire danger. J. For. 27(3):311-312.

Gisborne, H. T. 1929. A forest fire explosion. The Frontier 10(1):13-16.

Gisborne, H. T. 1929. Brush disposal. The Timberman 30(3):194.

Gisborne, H. T. 1930. Forest-fire research. Sci. Mon. 31:76-80.

Gisborne, H. T. 1931. Phases of fire problem. Am. Lumberman.

Gisborne, H. T. 1931. The scheme of forest fire control. J. For. 29(7):1077-1079.

Gisborne, H. T. 1931. Lightning on the lookouts. Am. For. 37(9):515-518,574-575. Republished in: Readers Digest, Oct. 1931. 559-561; Rangers of the Shield, Am. For. Assoc., 1934. 161-172.

Gisborne, H. T. 1933. Deadwood lying on duff drier than in air. J. For. 31(8):979-980.

Gisborne, H. T. 1933. Progress in forest fire research. Northwest Sci. 7(3):71-76.

Gisborne, H. T. 1934. Woodlands cut by the "selection method" less liable to fire damage. Washington, D.C.: U.S. Dep. Agric. Yearb. 1934. 376-378.

Gisborne, H. T. 1934. Measuring forest fire danger. Q. Nat. For. Protect. Assoc. (April).

Gisborne, H. T. 1935. Where is the forest meteorologist? Mich. For. 26.

Gisborne, H. T. 1938. Determination of normal fire danger. The Ames For. 29:27-31.

Gisborne, H. T. 1939. Forest pyrology. Sci. Mon. 49:21-30.

Gisborne, H. T. 1941. The new trend in fire control. Mich. For. 16-18,57.

Gisborne, H. T. 1948. Fundamentals of fire behavior. Fire Control Notes 9:13-24.

Gisborne, H. T. 1948. Calculating precipitation probabilities. The Timberman 49(1-0).

Gisborne, H. T. 1948. Dry ice to make rain and stop lightning. Proc. 39th Annu. Meet., West. For. and Conserve Assoc.

Gisborne, H. T. 1950. Tests show cigar and cigarette stubs come down hot. Fire Control Notes 11(2):28-29.

Graham, Donald P. 1958. Results of some silvicultural tests in pole blight diseased white pine stands. J. For. 56(4):284-287.

Graham, Donald P. 1959. Pole blight threatens western white pine. J. West. Conserv. 16(1):16,60,70.

Haig, I. T. 1930. A quarter century of silviculture in the western white pine type. Univ. Mont., For. Kaimin. 36-41.

Haig, I. T. 1931. Stand tables for second growth western white pine. Northwest Sci. 5(4):94-98.

Haig, I. T. 1936. Factors controlling initial establishment of western white pine and associated species. Yale Univ. Sch. For. Bull. 41. 149 p. + plates.

Hardy, Charles E. 1935. Half-inch fuel moisture sticks--how they are made. Fire Control Notes (Oct.)

Hardy, Charles E. 1954. Sticks measure fire danger. J. West. Conserv. 11(1):16-17,28-30.

Harrison, Kenneth, and Alexander H. Smith. 1968. A preliminary study of Clavariadelphus in North America. Mich. Bot. 7:35-57.

Haupt, Harold F. 1967. Snowpack outflow as measured by lysimeter-type gages. Ogden, UT: USDA For. Serv. Intermt. For. and Range Exp. Stn. Progress Rep. (unpubl.).

Haupt, Harold F. 1969. Research concerning management of snow for water yields in the northern Rocky Mountains. Proc. Int. Hydrol. Decade Workshop on Snow and Ice Hydrol. [Fort Collins, Colo., Aug. 18-22, 1969.]

Haupt, Harold F. 1970. A 2-year evaluation of the snowmelt lysimeter. West. Snow Conf. Proc. 1969:97-101.

Haupt, Harold F. 1972. Improved instrumentation for measuring melted precipitation on windswept topography. p. 75-85 in Distribution of Precipitation in Mountainous Areas, Geilo Symposium, Norway, Vol. II.

Haupt, H. F. 1972. Relation of wind exposure and forest cutting to changes in snow accumulation. Proc., Int. Symp. on the Role of Snow and Ice in Hydrology [Banff Alberta, Can.] 10 p.

Hayes, G. L. 1935. Don't let a "normal" deceive you. Washington, D.C.: USDA For. Serv., Serv. Bull. 19(17):4.

Helmers, Austin E. 1952. Precipitation measurements on wind-swept slopes. Northwest Sci. 26(2):65-68.

Hicks, Clifford B. 1949. Weather a la carte. Popular Mech. 92(4):167-172.

Hornby, L. G. 1936. Fuel type mapping -- its relation to forest fire control planning. Northwest Sci. 10(3):3-7.

Jemison, George M. 1932. Man-power placement and facilities for fire control. J. For. 30:626-627.

Jemison, George M. 1936. The effect of low vegetation on the rate of spread of fire in the northern Rocky Mountain region. Thesis, Yale Univ. 80 p.

Jemison, George M. 1937. Loss of weight of wood due to weathering. J. For. 35(5):460-462.

Kempff, Gerhard. 1924. Some results of winter slash disposal. The Timberman 25(10):146; Pulp & Paper Mag. of Can. 22(4):1026-1027.

Kempff, Gerhard. 1928. Nonindigenous western yellow pine plantations in northern Idaho. Northwest Sci. 2(2):54-58.

Lapham, M. H., and F. C. Youngs. 1925. Soil survey of the Priest River Experiment Station. USDA Bureau of Soils. Unpubl. file rep., Nov. 17, 1925. 10 p.

Larsen, J. A. 1916. Silvical notes on western larch. Proc. Soc. Am. For. 11(4):434-440.

Larsen, J. A. 1916. Seed testing with the Jacobsen germinating apparatus at the Danish seed control station. For. Q. 14(2):272-276.

Larsen, J. A. 1918. Growth of western white pine and associated species in northern Idaho. J. For. 16(7):839-840.

Larsen, J. A. 1918. Comparison of seed testing in sand and in the Jacobsen germinator. J. For. 16(6):690-695.

Larsen, J. A. 1922. Effect of removal of the virgin white pine stand upon the physical factors of site. Ecology 3(4):302-305.

Larsen, J. A. 1922. Some characteristics of seeds of coniferous trees from the Pacific Northwest. Nat. Nurseryman 30(9):146-149.

Larsen, J. A. 1924. Some factors affecting reproduction after logging in northern Idaho. J. Agric. Res. 28(11):1149-1157.

Larsen, J. A. 1924. Trend in silvicultural development in Germany. J. For. 22(5):506-512.

Larsen, J. A. 1925. Products from immature white pine stands in Idaho. Idaho For. 7:15-16.

Larsen, J. A. 1925. Natural reproduction after forest fires in northern Idaho. J. Agric. Res. 30(12):1177-1197.

Larsen, J. A. 1925. Methods of stimulating germination of western white-pine seed. J. Agric. Res. 31(9):889.

Larsen, J. A. 1926. Thinnings. Iowa State Univ., Ames Forester.

Larsen, J. A. 1928. Suggestions for forest research in Idaho. Idaho Forester.

Larsen, J. A. 1948. Early researches in the relations of forest fires and unusual weather conditions, humidity, duff moisture, and inflammability. Iowa State Univ. J. Sci. 22(4).

Larsen, J. A., and W. C. Lowdermilk. 1924. Slash disposal in pine forests of Idaho. West Coast Lumberman 47(553):50,59-63,75.

Leaphart, Charles D. 1959. Drought damage to western white pine and associated tree species. Plant Dis. Rep. 43(7):809-813.

Leaphart, Charles D., and Otis L. Copeland, Jr. 1957. Root and soil relationships associated with the pole blight disease of western white pine. Soil Sci. Soc. Am. Proc. 21(50):551-554.

Leaphart, C. D., Otis L. Copeland, Jr., and D. P. Graham. 1957. Pole blight of western white pine. Washington, D.C.: USDA For. Serv., For. Pest Leafl. 16. 4 p.

Leaphart, Charles D., and Lake S. Gill. 1955. Lesions associated with pole blight of western white pine. For. Sci. 1(3):232-238.

Lloyd, Merle G. 1959. Air currents send spores over ridge. West. Conserv. J. 16(1):32-33.

Lloyd, Merle G. 1960. Microclimate studies: results to date and their practical application to control problems in Region 1. Proc. Nat. Blister Rust Contr. Meeting, 1959 29:36.

Lloyd, M. G. 1960. Microclimate phases of blister rust control. Int. For. Dis. Work Conf. Proc. 59-64.

Lloyd, M. G. 1961. The contribution of dew to the summer water budget of northern Idaho. Bull. Am. Meteorol. Soc. 42(8):572-580.

Lloyd, Merle G., Clyde A. O'Dell, and J. H. Wells. 1959. A study of spore dispersion by use of silver-iodide particles. Am. Meteor. Soc. Bull. 40(6):305-309.

McAlpine, J. F. 1964. Descriptions of new Lonchacidae (Diptera). Can. Entomol. 96:701-757.

McConnell, R. C. 1965. Soil survey--Priest River Experimental Forest. USDA For. Serv. North. Reg. Progress Rep. 7 p.

MacCready, Paul B., Jr. 1957. The Munitalp cloud theodolite. Am. Meteorol. Soc. Bull. 38(8):460-464.

McHarg, C. K., J. Kittredge, J. F. Preston, and others. 1917. Developments in the marking of western white pine (Pinus monticola) in northern Idaho. J. For. 15(7):871-885.

Marshall, Robert. 1927. Influence of precipitation cycles on forestry. J. For. 25(4):415-429.

Marshall, Robert. 1928. The life history of some western pine stands on the Kaniksu National Forest. Northwest Sci. 2(2):48-53.

Miller, Orson K. 1962. Sporulation, germination, and early growth of Echinodontium tinctorium. Plant Dis. Rep. 46:576-578.

Nelson, Morlan W., and J. Alden Wilson. 1965. Summary of snow survey measurements for Idaho, 1921-1924. Portland, OR: US Dep Agric., Soil Cons. Serv.

Olson, D. S. 1953. Preliminary tests on relative inflammability of logging slash by species in the western white pine type. Univ. Idaho, For., Wildlife and Range Exp. Stn. Res. Note 5. 7 p.

Olson, D. S. 1953. Solids and voids in logging slash. Univ. Idaho, For., Wildlife and Range Exp. Stn. Res. Note 8. 4 p.

Olson, D. S., and George R. Fahnestock. 1955. Logging slash: a study of the problem in Inland Empire forests. Univ. Idaho, For., Wildlife and Range Exp. Stn. Bull. 1. 52 p.

Packer, Paul E. 1960. Some terrain and forest effects on maximum snow accumulation in a western white pine forest. West. Snow Conf. Proc. 28:63-66.

Packer, Paul E. 1962. Elevation, aspect, and cover effects on maximum snowpack water content in a western white pine forest. For. Sci. 8(3):225-235.

Palpant, E. H., John L. Thames, and Austin E. Helmers. 1953. Swith shelters for use with soil moisture units. p. 21-30 in Soil moisture measurement with the fiberglas instrument. New Orleans, LA: USDA For. Serv. South. For. Exp. Stn. Occas. Pap. 128.

Peffer, Al. 1950. Evolution of the fire danger meter. Am. For. 56(4):12-13.

Schaefer, V. J. 1957. Atmospheric studies from a moving weather observatory. Bull. Am. Meteorol. Soc. 38:124-129.

Slipp, Albert W., and Walter H. Snell. 1944. Taxonomic-ecologic studies of the Boletaceae in northern Idaho and adjacent Washington. Lloydia 7:1-66.

Squillace, A. E., and Roy R. Silen. 1962. Racial variation in ponderosa pine. For. Sci. Monogr. 2. 27 p.

Stickel, P. W. 1943. Local application of standard meteorological references. Northwest Sci. 17(4):75-81.

USDA Forest Service. 1949. Pole blight--this is how to recognize it. Joint Publ., Univ. Idaho Div. For. Pathol and USDA For. Serv. 5 p.

Watt, Richard F. 1950. Approach toward normal stocking in western white pine stands. Northwest Sci. 24(4):149-157.

Weidman, R. H. 1927. Prolific seed production in the forests of northern Idaho. Northwest Sci. 1(4):79-80.

Weidman, R. H. 1928. Forest research activities in the northern Rocky Mountain region. Northwest Sci. 2(2):33-37.

Weidman, R. H. 1929. What is research? Northwest Sci. 3(2):42-44.

Weidman, R. H. 1933. Progress of research in silviculture in the Inland Empire. Northwest Sci 7(3):67-71.

Weidman, R. H. 1939. Evidences of racial influence in a 25-year test of ponderosa pine. J. Agric. Res. 59(12):855-888.

Wellner, C. A. 1947. Forest protection in the silviculture of western white pine forests. Northwest Sci. 21(3):109-112.

Wellner, C. A. 1948. New disease threatens western white pine stands. J. For. 46(4):294-295.

Wellner, C. A., and F. D. Johnson. 1974. Research natural area needs in Idaho: A first estimate. Univ. Idaho., Coll. For., Wildlife and Range Sci. [Rep. of Natural Areas Workshop, April 24-25, 1974, Boise, Idaho.] 179 p.

Wicker, Ed F. 1967. Seed destiny as a klendusic factor of infection and its impact upon propagation of Arceuthobium spp. Phytopathology 57(11):1164-1168.

Wicker, Ed F., and C. Gardner Shaw. 1967. Target area as a klendusic factor in dwarf mistletoe infections. Phytopathology 57(11):1161-1163.

Wright, Ernest, and Donald P. Graham. 1952. Surveying for pole blight. J. For. 50(9):680-682.

Older U.S. Forest Serivce Publications (Not in Treesearch)

Copeland, Otis L., Jr. 1956. Preliminary soil-site studies in the western white pine type. Ogden, UT: USDA For. Serv. Intermt. For. and Range Exp. Stn. Res. Note 33. 4 p.

Fahnestock, George R. 1951. Correction of burning index for the effects of altitude, aspect, and time of day. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Res. Note 100. 4 p.

Fahnestock, George R. 1953. Inflammability of the current year's logging slash. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Res. Note 120. 10 p.

Fahnestock, George R. 1953. Chipping takes the hazard out of logging slash. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Res. Note 125. 5 p.

Fahnestock, George R. 1953. Relative humidity and fire behavior in logging slash. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Res. Note 126. 5 p.

Gisborne, H. T. 1922. Weather records applied to the fire problem. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Appl. For. Note 34. 4 p.

Gisborne, H. T. 1925. The effect of weather on the inflammability of forest fire fuels. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Appl. For. Note 58. 3 p.

Gisborne, H. T. 1934. Paired minimum temperatures as indices of fair or foul weather. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Appl. For. Note 65. 2 p.

Gisborne, H. T. 1935. The rating of forest fire danger. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Appl. For. Note 67. 3 p.

Gisborne, H. T. 1935. The character of the 1935 fire season in Region One. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Appl. For. Note 73. 4 p.

Gisborne, H. T. 1941. How the wind blows in the forest of northern Idaho. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. 14 p.

Gisborne, H. T. 1944. Slash burns well at B.I. 10 to 20. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Res. Note 35. 2 p.

Gisborne, H. T. 1945. Critical fire season indicated for 1945 in the northern Rocky Mountain region. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Res. Note 36. 4 p.

Hardy, Charles E., Charles E. Syverson, and John H. Dieterich. 1955. Fire weather and fire danger station handbook. Ogden, UT: USDA For. Serv. Intermt. For. and Range Exp. Stn. Misc. Publ. 3. 84 p.

Hayes, G. L. 1937. Variations of some fire danger factors with altitude, aspect, and time of day. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Appl. For. Note 80. 8 p.

Hayes, G. L. 1942. A discussion of hygrographs. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Res. Note 25. 6 p.

Helmers, Austin E. 1946. How heavily should western white pine be pruned? USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Res. Note 41. 5 p.

Helmers, Austin E. 1946. Pruning wound healing on western white and ponderosa pines. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Res. Note 45. 6 p.

Jemison, G. M. 1932. Climatological summary for the Priest River Forest Experiment Station, 1912-1931, inclusive. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. 27 p.

Jemison, George M. 1932. Drought not yet broken. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Appl. For. Note 62. 2 p.

Kempff, Gerhard. 1923. Some results of winter slash disposal. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Appl. For. Note 41. 3 p.

Larsen, J. A. 1921. Relative humidity of the atmosphere and its relation to the fire problem. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Appl. For. Note 6. 1 p.

Larsen, J. A. 1921. Wind and its relation to forest fires. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Appl. For. Note 7. 5 p.

Larsen, J. A. 1921. Sunshine and air temperature in relation to forest fires. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Appl. For. Note 9. 6 p.

Leaphart, Charles D. 1958. Root characteristics of western white pine and associated tree species in a stand affected with pole blight of white pine. Ogden, UT: USDA For. Serv. Intermt. For. and Range Exp. Stn. Res. Pap. 52. 11 p.

MacCready, Paul B., Jr., Vincent J. Schaefer, John H. Dieterich, and J. S. Barrows. 1955. Project Skyfire: cloud and lightning observation handbook. Ogden, UT: USDA For. Serv. Intermt. For. and Range Exp. Stn. Misc. Publ. 5. 47 p.

Marshall, Robert. 1928. Natural reproduction in the western white pine type. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Progress Rep. 72 p.

USDA Forest Service, Pole Blight Investigations Steering Committee. 1952. Pole blight--what is known about it. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Misc. Publ. 4. 17 p.

Watt, Richard F. 1950. Growth in understocked and overstocked western white pine stands. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Res. Note 78. 3 p.

Watt, Richard F. 1952. Western white pine stands show irregular growth pattern. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Res. Note 113. 1 p.

Watt, Richard F. 1953. Site index changes in western white pine forests. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Res. Note 132. 2 p.

Weidman, R. H. 1922. Intensive management on a demonstration forest. Ogden, UT: USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Appl. For. Note 35. 3 p.

Weidman, R. H. 1925. Ten years' trial of some introduced species at Priest River Experiment Station. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Appl. For. Note 56. 3 p.

Wellner, C. A. 1946. Improving composition in young western white pine stands. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Res. Note 43. 6 p.

Wellner, C. A. 1946. Estimating light intensity in residual stands in advance of cutting. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Res. Note 47. 4 p.

Wellner, C. A. 1947. Marking instructions for the white pine type in the northern Rocky Mountain region. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. 14 p.

Wellner, C. A. 1952. A vigor classification for mature western white pine trees in the Inland Empire. USDA For. Serv. North. Rocky Mt. For. and Range Exp. Stn. Res. Note 110. 3 p.

Ecological Information

In terms of climate, topography, flora, and fauna, the Northern Rocky Mountains are a diverse region. Within this context, Priest River Experimental Forest is an excellent representation of the forested ecosystems that are common to an area west of the continental divide and north of the Snake River Plain.

Climate and weather

In general terms, the Priest River-Northern Rocky Mountain climate is transitional between a northern Pacific coastal type and a continental type.

The Pacific influence is noted particularly by the late autumn and winter maximum cloudiness and precipitation. The relatively moderate average winter temperatures, compared with areas east of the continental divide, also show the Pacific influence. Summer is characteristically sunny and dry, though July and August are the only distinct summer months.

The average annual (water year, Oct 1 – Sep 30) precipitation at the Forest headquarters is 32.17 inches (817 mm). At higher elevations, precipitation slightly increases. The Benton Spring rain gauge at 4,774 feet-elevation (1455 m) receives an annual average of 36.42 inches (925 mm) of precipitation. The wettest months are November through March, which receive close to 60% of the annual total precipitation. Snowfall accounts for more than 50% of the total precipitation at elevations above 4,593 feet (1400 m). Snow cover usually persists in the valleys from early December through the end of March, with maximum averages around 19.29 inches (49 cm) deep. High-elevation snowpack can reach an average depth of 51.97 inches (132 cm) at the end of March and sometimes remain into June.

The monthly mean temperatures at the headquarters range from 25oF (-4oC) in January to 64oF (18oC) in July. The annual mean temperature is 45oF (7oC). Extreme temperatures have ranged from a high of 103oF (40oC) to a low of -36oF (-38oC). The climate at PREF provides a transition between the strong maritime influence on the coniferous forests of the coastal Pacific Northwest domain and the dryer, colder interior flora found east of the continental divide. The long-term daily weather record, coupled with the snow pack record, allow researchers to document subtle changes in weather patterns. This is particularly relevant to stakeholders within the drainages of the Priest, Pend O'Reille, Snake, Clearwater, and Columbia River systems.


The soils of the mountain slopes are underlain by rocks, including granites, gneiss, and schist. The major rock type appears to be gneiss. The schist contains prominent biotite and muscovite mica, and is thinner bedded than the gneiss. Soil surface horizons have formed in aeolian loess and volcanic ash. Surface textures are mostly silt loams, relatively fine-textured soils with low rock contents and high water-holding capacity.

Soils at elevations up to 3,280 feet (1,000 m) on southerly aspects are associated with shallow Saltese soils with minor amounts of deeper Jughandle soils on concave slopes of the drainages. Above this threshold, the Jughandle soils and associated phases of exposure, except the subalpine phase above 4,593 feet (1400 m), are mapped in the zone of maximum soil moisture and soil temperature effectiveness. Fertility is high on these sites. Above 4,593 feet (1,400 m), the colder soils predominate, though moisture is near maximum. South-facing slopes near this elevation and above contain the Horsehead soils, which represent a prairie-forest transition to the subalpine environment.

The soils of Priest River Experimental Forest, Jughandle, Cabinet, Springdale, and Chamokane, are extensively mapped in forest lands in northern Idaho. Saltese and Horsehead soils have been mapped in Montana in the St. Regis and Ninemile area. A detailed geologic map of the Sandpoint Quadrangle, which includes the entire Priest River drainage, was completed in 1979.

Forest productivity

Moisture usually limits high timber production on soils of the river terraces and lacustrine benches, and the south-facing slopes at lower elevations. Relatively high evaporation from prevailing southwest winds helps make these sites dry. The stream terraces and fans of Benton and Canyon Creeks have favorable run-in moisture from side slopes, and fertility and productivity are near maximum in the area. Soils of the middle elevations, and on northerly, easterly, and westerly slopes have highest fertility and productivity associated with favorable moisture-temperature relationships. Fertilizer experiments have demonstrated that nitrogen and, on metamorphic bedrocks, potassium deficiencies, may co-limit productivity. Soils of the high elevations have less favorable soil temperature and lowest fertility (McConnell 1965).

Terrestrial ecosystems

About two thirds of the Experimental Forest is covered in mixed conifer forest more than 100 years old. Most of this is timber in the 120- to 140-year age class (resulting from a fire ca. 1860). The remainder is in timber more than 200 years old. The other third of the Experimental Forest is in non-stocked areas or in young timber on harvest units and burns that have occurred since PREF was established (Wellner 1976).

The most detailed and intensive sampling of habitat types and cover types at PREF was reported by Daubenmire (1973) (also see Wellner 1976). A species list of vascular flora collected and identified by Daubenmire is found in Wellner's 1976 publication. Reconnaissance surveys and mapping have helped determine cover types and habitat types. Habitat types within PREF are best described as "complex" because of the extremely rapid changes in aspects and from wet to dry habitats. Plant species diversity is high due to the number of different habitat types that are intimately intermixed. Within the Wellner Cliffs RNA are plants indicative of wet habitats — western redcedar (Thuja plicata), wild ginger (Asarum caudatum), baneberry (Actaea rubra), and devils club (Oplopanax horridum). These occur within a few feet of dry habitats that support species such as ponderosa pine (Pinus ponderosa), lodgepole pine (P. contorta), Idaho fescue (Festuca idahoensis), and bluebunch wheatgrass (Agropyron spicatum) (Ferguson and Zack 2006).

Mosses and lichens were inventoried along the lower section of Canyon Creek within the RNA in 2001. During this inventory, the moss Ulota megalospora was recorded for the first time in Idaho. A list of lichens observed by Mike Hays at Wellner Cliffs RNA was complied in July 1997.

Stream ecosystems

A survey of lower Canyon Creek was conducted by Fred Rabe in 1995 (Rabe 1995). The surveyed portion of the stream was the last 0.3 miles (0.5 km) of Canyon Creek before it exits the Wellner Cliffs RNA. In this section of the stream, Canyon Creek is a 2nd order stream with v-shaped valley form and 4-6% gradient. Stream size is 5–15ft (1.5–4.6m), averaging 11ft (3.4m). Sinuosity index is 1.3 (average) with many debris dams caused by windthrown trees falling into the stream. This riffle-pool stream had a pH of 7.3 and 45oF (7.2oC) temperature on September 25, 1995. Canopy coverage was estimated at 60–75% of the channel shaded by vegetation, which was mostly shrubs and conifers.

Rabe compiled a list of 40 macroinvertebrate taxa found in the RNA. A low biotic index was calculated from these data, indicating the macro invertebrate community is quite intolerant of poor water quality conditions.In his summary, Rabe notes that lower Canyon Creek would be a good choice as a reference site for comparison with impacted streams of similar size and flow.

Research – Historical and Present

Since the Priest River Experimental Forest began, numerous educators, Forest Service researchers, and state and private forestry personnel have used the site. Research conducted by J.A. Larsen, Harry Gisborne, Ken Davis, Charles Wellner, and Irvine Haig provided information on basic forestry principles still used today for managing Rocky Mountain forests. These and other researchers throughout PREF's history have made it a key location for conducting studies of forest ecosystems of the Northern Rocky Mountains.

Old photograph of mature western white pine
Mature western white pine forest
Regeneration studies using shelterwood, seedtree, and clearcut methods have provided information for regenerating mixed-conifer forests. Site preparation, planting, cleaning, weeding, and thinning studies have provided information on regeneration and maintenance of forest stand composition and growth.

Performance trials began in 1911 with a species variation test of ponderosa pine, composed of seed sources from 22 locations throughout the western United States. Researchers have studied growth characteristics of disease-resistant western white pine since 1955, and seed-transfer rules and zones for western conifers.

Fire research began with the development of the first fire danger rating system, followed by studies on weather factors, fire behavior, fuel inflammability, and fire effects. This effort is the foundation for the current fire danger systems now used throughout the United States and Canada.

Researchers have studied forest growth and yield on the PREF since 1914, with several permanent plots re-measured at regular intervals. Information from these plots and other locations throughout the Northern Rocky Mountains is used to verify and test growth and yield computer models.

Currently, researchers are studying ecosystem processes and functions, including: the effects of management activities on long-term soil productivity, coarse woody debris function, atmospheric deposition, western white pine seedling development in canopy gaps, forest structure impacts on water yield and quality, white bark pine progeny trials, and carbon sequestration in mixed-conifer forests.

Research Accomplishments

The following major research findings were developed at Priest River:

  • Rust-resistant western white pine;
  • Mapping of habitat types, development of the Prognosis computer model, forerunner to the present Forest Vegetation Simulator (FVS);
  • Beginnings of fire behavior, fire danger rating, and fire effects information;
  • Influence of forest structure on water yield and quantity; and
  • Importance of coarse woody debris in maintaining forest productivity

Long-term Monitoring and Data

The Forest Service has collected and archived long-term datasets of daily weather (1911), snow pack (1937), tree growth (1914) and streamflow (1938). In 2003, PREF became a monitoring site (site # ID02) of the National Atmospheric Deposition Program (NADP).

The climatic, hydrological, and atmospheric datasets collected at PREF are public domain and available to interested parties. Raw data are archived at the PREF and the Moscow Forestry Sciences Lab, and is also available at several websites:

Control Weather Station

Daily Observations (11/27/1911 to present) are available. Search using the Priest River Experimental Station, ID # 107386. The data set consists of daily maximum and minimum temperature, precipitation, daily snowfall and accumulated snow fall.

  • The NCDC website has the complete record in txt or pdf formats.
  • The Western Regional Climate Center has monthly averages and station metadata.
  • A reformatted version of the NCDC data, with gaps filled from PREF records, is available as an xlsx document at the Moscow Forestry Sciences Lab.

Snow Pack Data Sets

(WY 1937 to present) are available for the Benton Meadow (elev. 2,380 ft, 725 m) and Benton Spring (elev. 4,775 ft, 1,455 m) snowcourses:

  • Natural Resource Conservation Service (NRCS) has the full record for both snowcourses. Visit the NRCS National Water and Climate Center website and select the snow course of interest (Benton Meadow or Benton Spring).

Surface, Terrain, and Canopy Height Models

These data publications each contain three raster datasets with a spatial resolution of one meter: 1) a digital surface model (DSM), which represents the highest lidar return in each grid cell; 2) a digital terrain model (DTM), a representation of the ground surface with vegetation and other non-ground returns removed; and 3) a canopy height model (CHM), a representation of the height of vegetation above the ground surface. 

Atmospheric Chemistry

On December 31, 2002, a National Atmospheric Deposition Program (NADP) site was established in Priest River Experimental Forest. The site designation is ID02. Data can be found at the NADP webpage.


  • Benton Spring (elev. 4,725 ft, 1,440 m), monthly observations, transcribed into Excel spreadsheets from 1960 to present.
  • Benton gauging dam (elev. 2,640 ft, 805 m), daily and monthly data, beginning from 1941 to present.

Stream Flow from Benton Gauging Dam

Digitized gauge heights from 1955 to present are available from the Moscow Forestry Sciences Lab. This data will eventually be archived in the Rocky Mountain Research Station database.

Tree Growth Data

Derived from permanent growth and yield plots, 1914 to present is available at the Moscow Lab.

Archaeological data

A detailed archaeological survey of PREF was conducted in 1978 and is on file at the Moscow Forestry Sciences Lab.

Facilities Information

Road access to Priest River Experimental Forest is by State Highway 2 from Spokane, Washington to Priest River, Idaho. From Priest River, drive north on State Highway 57 for 3 miles, then north on Peninsula Road, a Bonner County road (5 miles pavement and then 5 miles of gravel) to reach the Experimental Forest. Within PREF, the entry and forest roads are surfaced with gravel or native soils.

The headquarters site consists of an office/lab building, three residential buildings, a bunkhouse/mess hall, and modest shop. A full-time resident and employee occupy a fourth residence. All were constructed by the Civilian Conservation Corps between 1934 and 1939 and are listed in the National Register of Historic Places. The Gisborne Fire Lookout is listed on the National Historic Lookout Register. A conference building, with a capacity of 50, was added in 1998.

During the field season, the Experimental Forest averages 1000 use-days by Forest Service personnel and their cooperators. The residential buildings and bunkhouse have a capacity of 27 beds. During the winter months, a cabin and the bunkhouse/mess hall are shut down, reducing bed space to 18. The residential buildings are ADA compliant and provide visitors with full kitchen facilities and linens.

Research Opportunities

The diversity of conifer species, age classes, and associated flora and fauna provide endless opportunities for research projects. Forest conditions range from pristine to highly disturbed. Of the 13 major conifer species found in the Northern Rocky Mountains, all are represented in PREF. In addition, long-term climate data is valuable for characterizing subtle weather changes in this ecosystem and can supplement a variety of ecological studies. Priest River Experimental Forest GIS layers and LiDAR coverage are available at the Moscow Lab.