Research in the Siskiyou and Klamath
Mountain Regions

Last updated June 1997

This web page was established to support ecological research in the Siskiyou and Klamath Mountains in several ways:

First, as a tool to be used in conjunction with the 1997 First conference on Siskiyou Ecology Second, by creating an information library and electronic links to literature, plant lists, researchers and projects related to the Siskiyous.

The utility of these resources will depend on the participation of researchers and advocates like yourself. As well as the features we have planned, we look forward to any suggestions or assistance for further developments. We are currently building the following resources:

Siskiyous Ecology Conference

The First Conference on Siskiyou Ecology was held May 30 - June 1, 1997 in Kerby, Oregon. The conference included presentations on a broad spectrum of topics, including past and current research on regional flora and fauna, the botanical significance of the area, unique geological features, and historical changes influencing the integrity of the Siskiyou Mountain region, as well as the Klamath Mountain region. There also were educational workshops and field trips to areas of ecological interest.

Keynote speakers included Dr. Art Kruckeberg, Professor Emeritus and Chairman of the Botany Department at the University of Washington, Dr. Frank Lang Chairman of the Biology Department and Professor of Biology at Southern Oregon State College and Donald Zobel, Professor of of Botany and Plant Pathology at Oregon State University.

The conference, was organized by the Siskiyou Regional Education Project . Visit their web site for current news and events.

"The Northwest has perhaps the most serious gap in the system of preserved lands in the continental United States: the Klamath-Siskiyou region, biologically one of the richest areas in North America, indeed one of the richest temperate areas in the world."
-Dr. Elliot A. Norse, Ancient Forests of the Northwest.

Siskiyous Literature

The literature database contains compiled references of researchers with an interest in the ecology and natural history of the Siskiyou and Klamath Mountains of Southern Oregon and Northern California. Although the current list is partial and very incomplete, our goal is to provide access to a quick and comprehensive list of literature, both published and unpublished, on the Siskiyous.

In addition to this WWW home page, we are also developing a public-access library of all articles to be housed at the Siskiyou Regional Education Project in Cave Junction, Oregon. If you are able to provide us a hard copy of any articles for the library, you may send it to the same address as that listed below for literature citations.

Siskiyou Links

We would also like to compile a list of Siskiyous researchers and their projects (past, present and future). As well as names, addresses and research or project descriptions, this can include links to the web pages of researchers working in the Siskiyous and to other Siskiyou-related web sites. If you have links to add, please send the urls to Bart's email. In the near future we will develop a means to automatically add the links.

Plans for the future

Our next step in database development will be to incorporate this information in a searchable library-style database. This would allow searches by author, subject, keyword, etc. As part of this we would like to include abstracts or short article summaries that you may be able to contribute.

We would also like to develop several other resources as part of this web site:

if you have thoughts or suggestions, please send them to us at:,

Thank you for your help. We hope you find this database useful in your work and encourage you to join with us in understanding and protecting this magnificent landscape.

Jennifer Beigel, Siskiyou Regional Education Project
Bart Johnson, University of Oregon

Siskiyous Literature

This database represents the compiled references of researchers with an interest in the ecology and natural history of the Siskiyou and Klamath Mountain Regions. Since much of the literature on the Siskiyous is in the form of unpublished and difficult-to-locate reports, even incomplete references are welcome -- we will put them on the web to see if anyone knows the full reference or source.

If you are able to contribute any further references (including abstracts or summaries, if possible), you can do so in one of several ways:

If you have the references in an electronic file, you can send the information by e-mail to, or you can mail the file on a 3 1/2" floppy disk to:

Bart Johnson
Dept. of Landscape Architecture
5234 University of Oregon
Eugene, OR 97403-5234

If you do not have an electronic copy, please send a hard copy to the above address.

References to Literature on the Siskiyou Mountains Region

Agee, J.K. 1991. Fire history along an elevational gradient in the Siskiyou Mountains, Oregon. Northwest Science 65:188-199.

Alexander, E.B. 1988. Morphology, fertility and classification of productive soils on serpentinized peridotite in California (U.S.A.). Geoderma 41:337-351.

Amaranthus, M.P. and J.M. Trappe. 1993. Effects of erosion on ecto- and VA-mycorrhizal inoculum potential of soil following forest fire in southwest Oregon. Plant and Soil 150:41-49.

Amaranthus, M.P. Investigation of a rare conifer, Picea breweriana: its history, habit and prospects for the future. Unpublished report. Siskiyou National Forest. 11p.

Amaranthus, M.P., R.M. Rice, N.R. Barr, and R.R. Ziemer. 1985. Logging and forest roads related to increased debris slides in southwestern Oregon. Jounral of Forestry April:229-223.

Atzet, T. and D. Wheeler. 1982. Historical and Ecological Perspectives on fire activity in the Klamath Geological Province of the Rogue River and Siskiyou National Forests. R6 Range-102-1982. Portland, OR: US Department of Agriculture, Forest Service, Pacific Northwest Region. 16 p.

Atzet, T. and D. Wheeler. 1984. Preliminary plant associations of the Siskiyou Mountain Province. U.S.D.A. Forest Service PNW Region, Portland, Oregon. 315 p.

Atzet, T., and R.E. Martin. 1991. Natural disturbance regimes in the Klamath Province. Proceedings of the Symposium on Biodiersity of Northwestern California.

Atzet, T. 1979. Description and classification of the forests of the upper Illinois River drainage of southwestern Oregon. Ph.D. dissertation, Oregon State University, Corvallis.

Beckman, S.D. 1978. Cultural resource overview of the Siskiyou National Forest. U.S.D.A. Forest Service, Grants Pass, OR.

Borchers, J. 1992. The influence of soil and texture aggregation of carbon and nitrogen dynamics in southwestern Oregon forests and clearcuts. Canadian Journal of Forest Research 22(3): 298-305.

Chaney, R. 1940. Tertiary Forests and Continental History. Bulletin of the Geological Society of America 51: 469-488

Detling, L. E. 1948. Concentration of Environmental Extremes as the Basis for Vegetation Areas. Madrono 9(5): 169-185.

Detling, L. E. 1953. Relict Islands of Xeric Flora West of the Cascade Mountains in Oregon. Madrono 12(2): 39-47.

Detling, L.E. 1947. Environmental Extremes and Endemism . Madrono 9(4): 105-136.

Franklin, J.F. and C.T. Dryness. 1988. Natural Vegetation of Oregon and Washington. Oregon State University Press: Corvallis.

Franklin, J.F. and C.T. Dyrness. 1973. Natural vegetation of Oregon and Washington. U.S.D.A. Forest Service, Portland, Oregon, USA.

Frissell, C.A. 1991. Water quality, fisheries and aquatic biodiversity under two alternative forest management scenarios for the west-side federal lands of Washington, Oregon and northern California. A report prepared for The Wilderness Society, Seattle.

Frost, E.J. 1992. The effects of forest-clearcut edges on the structure and composition of old-growth mixed conifer stands in the western Klamath Mountains. Thesis. Humbolt State University, Arcata, California, USA.

Gilkey, H. 1951. A new fritillaria from Oregon, Fritillaria gentneri. Madrono 11:137-141.

Guerrant, E.O. 1992. An Electrophoretic Investigation into the Status of Fritillaria gentneri (Liliaceae): Is It a "Good" Species or Not? Unpublished report. Oregon State Department of Agriculture and Bureau of Land Management, Medford District.

Irwin, W.P. 1966. Geology of the Klamath Mountains province. In, E.H. Bailey, ed., Geology of Northern California. Calif. Div. Mines and Geology Bull. 190:19-38.

Jules, E.S. 1996. Yellow jackets (Vespula vulgaris) as a second seed disperser for the myrmecochorous plant, Trillium ovatum. American Midland Naturalist 135:367-369.

Jules, E.S. In press. Consequences of forest fragmentation for the understory plant, Trillium ovatum (Liliaceae). In T.N. Kaye, A. Liston, R.M. Love, D. Luoma, R.J. Meinke, M.V. Wilson, editors. Conservation and Management of Native Flora and Fungi. Native Plant Society of Oregon, Corvallis, Oregon.

Kagan, J. 1988. Draft Species Management Guide for Senecio hesperius. Unpublished document on file at the Oregon Natural Heritage Program, Portland, OR.

Kruckeberg, A. R. 1951. Intraspecific variability in the response to certain native plant species to serpentine soil. American Journal of Botany 38:408-419.

Kruckeberg, A. R. 1954. The ecology of serpentine soils: plant species in relation to serpentine soils. Ecology 35(2):267-274.

Kruckeberg, A. R. 1969. Soil diversity and the distribution of plants with examples from western North America. Madrono 20:129-154.

Kruckeberg, A. R. 1970. Plant life on serpentine and other ferro-magnesium rocks in northwestern North America. Syesis 2:15- 144.

Kruckeberg, A. R. 1984. The flora on California's serpentine, part II. Fremontia (April):3-10.

Kruckeberg, A. R. 1985. California Serpentines: Flora, Vegetation, Geology, Soils and Management Problems. U.C. Publications in Botany: Vol. 28.

Lang, F. 1994. Hastingsia bracteosa/atropurpurea: A Taxonomic Status Report. Unpublished report prepared for the USDA Forest Service, Siskiyou National Forest.

Lang, F. and C. MacDonald. 1987. Species Management Guide for Hastingsia bracteosa Wats. Unpublished report on file at The Nature Conservancy of Oregon, Portland, Oregon

Lewis, P. A. 1966. The Plant Communities of the Marble Mountain Wilderness Area, Siskiyou County, California. Unpubl. Master's thesis. Pacific Union College.

Long, W. A. 1977. Reconnaissance of the Glacial Geology of the Siskiyou Mountains. U.S. Department of Agriculture, Six Rivers National Forest.

McKinley, G. and D. Frank. 1995. Stories on the land: an environmental history of the Applegate and Upper Illinois Valleys. BLM, Medford District.

Mills, L.S. 1993. Extinction in habitat remnants: proximate mechanisms and biogeographic consequences. Ph.D. dissertation. University of California, Santa Cruz, California, USA.

Mills, L.S. 1995. Edge effects and isolation: red-backed voles on forest remnants. Conservation Biology 9:395-403.

Mills, L.S. 1996. Fragmentation of a natural area: dynamics of isolation for small mammals on forest remnants. Pages 199-219 in R.G. Wright, editor. Natural Parks and Protected Areas. Blackwell Press, Cambridge, Massachussetts, USA.

Oregon Natural Heritage Program. 1995. Rare Threatened and Endangered Plants and Animals of Oregon. Oregon Natural Heritage Program, Portland, Oregon. 84 p.

Parker, E.L. 1963. The geographic overlap of noble and red fir. Forest Science 2:207-216.

Pullen, P. 1995. Overview of the environement of Native inhabitants of southwestern Oregon, Late Prehistoric Era. U.S.D.A. Forest Service, Grants Pass, OR.

Roth, L.F., E.J. Trione, and W.H. Ruhman. 1957. Phytophthora induced root rot of native Port-Orford-cedar. Journal of Forestry 55:294-298.

Stebbins, G.L. and J. Major. 1965. Endemism and speciation in the California flora. Ecological Monographs 35:1-35.

U.S. Forest Service. 1989. Siskiyou National Forest Plan. Appendix F: Botanical and Research Natural Areas.

U.S.D.A. Soil Conservation Service. 1983. Soil Survey of Josephine County, Oregon. National Cooperative Soil Survey.

Wallace, D.R. The Klamath Knot. Sierra Club Books.

Waring, R.H. 1969. Forest plants of the eastern Siskiyous, their environmental and vegetational distribution. Northwest Science 43:1-17

Waring, R.H. and S.W. Running. 1975. Environmental limits of an endemic spruce, Picea breweriana. Can. J. Bot. 53:1599- 1613.

White, C.D. 1971. Vegetation-soil chemistry correlations in serpentine ecosystems. Unpublished dissertation on file at the University of Oregon, Eugene, 151 pp.

Whittaker, R.H. 1954. The ecology of serpentine soils. The vegetational response to serpentine soil. Ecology 35:275-288.

Whittaker, R.H. 1960. Vegetation of the Siskiyou Mountains, Oregon and California. Ecological Monographs 30:279-338.

Whittaker, R.H. 1961. Vegetation History of the Pacific Cost States and the “Central” Significance of the Klamath Region. Madroño 16(1): 5-23.

Zobel, D.B. 1990. Chamaecyparis lawsoniana (A. Murr.) Parl.: Port-Orford-cedar. Pages 88-89 in Burns, R.M, B.H. Honkala, coordinators. Silvics of North America: Volume 1, conifers. USDA Forest Service, Washington, DC.

Zobel, D.B. and G.M. Hawk. 1980. The environment of Chamaecyparis lawsoniana. American Midland Naturalist 103:280-297.

Zobel, D.B., L.F. Roth, and G.M.Hawk. 1985. Ecology, pathology, and management of Port-Orford-Cedar (Chamaecyparis lawsoniana). USDA Forest Service General Technical Report PNW-184.

Annotated Bibliography

Chaney, R. 1940. Tertiary Forests and Continental History. Bulletin of the Geological Society of America 51: 469-488

Throughout the Tertiary, North America has been a rising continent as judged by the record of its vegetation. Narrow bordering seas have largely withdrawn, mountain ranges have been uplifted, until we of the Recent epoch have inherited great diversity of environment. Controlled largely by these earth changes, the climate has tended toward lowered temperature and rainfall. Resulting forest migrations across the continents enable us to determine the sequence and age of plant-bearing deposits. The pattern of land vegetation around the Northern Hemisphere indicates that the factors controlling air and water circulation have been essentially the same since the Eocene-that North America and Eurasia have stood in their present positions since the dawn of the Cenozoic. Evidence of land plants of earlier times, less completely known and interpreted, seems also to refute the hypothesis of continental drift. Forest under compulsion of climatic change, rather than the continents on which they live, appear to have been the wanderers during the history of life upon earth.

Reviewer Comments:
Despite the rebuke of continental drift-this article contains possibly some interesting information on the Klamath/Siskiyou area.

Detling, L.E. 1947. Environmental Extremes and Endemism. Madrono 9(4): 105-136.

The degree of endemism in the nine major plant associations on a transect through western and central Oregon is compared with annual precipitation, summer precipitation, January minimum temperature and summer maximum temperature in the sue associations. Its found that the higher percentages of endemism occur in those associations in which the greater number of climatic factors reach one of their extremes in the area. It is pointed out that the centers of floral areas richest in endemic species coincide with areas in which occur the end pints of a number of climatic gradients, and it is suggested that taxonomic and distributional studies be based upon geographic areas constituted along these lines.

Detling, L. E. 1948. Concentration of Environmental Extremes as the Basis for Vegetation Areas. Madrono 9(5): 169-185.

In any region extensive enough to show physiographic variability, the climatic or other environmental factors occur as gradients. Previous investigation has shown that where several extremes of these gradients occur together they mark the center of an area rich in endemic plant species. In this study the Pacific Northwest has been divided into sixteen vegetation areas, each built around one of those extremes. Each area is briefly characterized as to its dominant plant association. Examples from the recent works of monographers show how the distribution of most plant species fits into the pattern of these areas.

Detling, L. E. 1953. Relict Islands of Xeric Flora West of the Cascade Mountains in Oregon. Madrono 12(2): 39-47.

Distribution patterns of thirty-two xeric plant species occurring on isolated mountain tops west of the Cascade Mountains of Oregon suggest that they are relicts of a once widespread xeric flora which originated, first, in the Rogue River Valley, and secondly, on the plateaus of east-central Oregon. They have persisted on the mountain summits because of the arid and relatively warm conditions of the shallow soil and exposed dark rocks, and the consequent freedom from competitions with the surrounding mesic forest types.

Whittaker, R.H. 1961. Vegetation History of the Pacific Cost States and the “Central” Significance of the Klamath Region. Madrono 16(1): 5-23.

1. The Klamath Region of northwestern California and southwestern Oregon is an area of old and geologically complex mountains, supporting a complex vegetation pattern and a diverse flora rich in narrowly endemic species. The region is a floristic and vegetational “center” for the forests of the western United States.
2. Vegetation history of the Pacific Coast states since Miocene time has involved progressive shrinkage of Arcto-Tertiary forest and progressive expansion and differentiation of Madro-Trertiary communities.. Mixed forests (coastal Sequoia and mixed evergreen forests) most nearly related to the Arcto-Tertiary forests in the West are now limited to the Klamath Region and northern California Coast Ranges, while woodland, chaparral, and grassland communities primarily of Madro-Tertiary derivation have entered the Klamath Region from the south to form the more xeric part of its vegetation pattern.
3. Floristic diversity of the Klamath Region has resulted from climatic and parent -material diversity, together with age of the mountains which has permitted species of diverse histories and environmental relations to survive there, often as relicts restricted to special parent materials or situations.