Bear Basin Butte Botanical Area (excerpts from the Special Interest Area Management Strategy for Six Rivers National Forest) Lisa D, Hoover and Mark Smith Botanist and Geologist, Six Rivers National Forest Along the crest of the Siskiyou Mountains, in the Smith River National Recreation Area of the Six Rivers National Forest, one can view an extraordinarily high diversity of conifers within the Bear Basin Butte Botanical Area (BBA). The area encompassing the BBA covers 8,500 acres and is located in the headwaters of the Middle and South Fork Smith River. Elevation ranges within the area extend from 1,360 feet to 5,290 feet at Bear Basin Butte. Due to its rich geologic history, parent material diversity, landscape position, and topographic variation, the BBA contains an array of habitats that support a unique blend of species converging from the north and south, as well as refugia sites for species present during glacial times. Specific stands within the BBA have been described as unique or one of a kind (Sawyer and Keeler-Wolf 1995). The only other place where this degree of conifer diversity exists is within the Salmon Scott area of the Klamath Mountains.
The BBA is considered a Significant Natural Area by the California Department of Fish and Game and also considered globally rare. The BBA is distinctive for its conifer diversity concentrated in a relatively small area. Brewers spruce (Picea breweriana), one of the most noteworthy and noble species, is endemic to the Klamath Region, occurring in local and disjunct populations. Its habitat includes high elevations, talus rocky ridges, and moraine substrates of metasedimentary, granitic, serpentine or metavolcanic origin. Alaska cedars (Cupressus nootkatensis) range extends from the Siskiyou Mountains to south central Alaska. Its habitat is similar to that of Brewers spruce, occurring as individual trees or small stands, on rocky and well drained soils at high elevations. Mountain hemlock (Tsuga mertensiana) ranges from the Sierra Nevada and Siskiyou Mountains, the Cascade Ranges in Oregon to southern Alaska. Mountain hemlock is typically associated with north facing slopes and occurs as small stands where there is a lingering snow pack. Port-Orford-cedar (Cupressus lawsoniana) aligns the creeks that meander through the area, providing the primary conifer cover in the riparian areas. The Port-Orford-cedar communities associated with the headwater creek within the BBA are some of the few remaining which are free of the lethal Port Orford cedar root disease (Phytopthora lateralis).
Paramount to the appreciation of the BBA and its conifer diversity is the understanding of the geomorphic and geologic history of the area. The BBA is located within the western Klamath Mountains province and is a geologically complex area, underlain by a variety of metamorphosed sedimentary and volcanic rocks, as well as some plutonic igneous rocks. The terrain varies among the different bedrock units due to differences in their physical structure relative to slope, resistance to weathering, soil development, and the geomorphic history of different positions in the landscape. The bedrock units are as follows: Galice metasediments, ultramafic rocks, metavolcanic rocks, metasedimentary rocks, and intrusive rocks (including dioritic plutons).
Geomorphic processes have influenced the pattern and composition of the vegetation in the area. Most of the areas history is related to mass wasting and gradual surface erosion. North facing slopes bear marks of an ancient erosional epoch where steep, semi barren rock, and talus slopes occur. Glacial ice was generally restricted to small pockets on north facing slopes. Land sliding has been a dominant process for thousands of years. The most dramatic feature is the Bear Basin slide that developed along a major weakness plane in bedrock northeast of Bear Basin Butte. Much of the terrain in the BBA is extremely rugged and steep because of persistent mass wasting. High rates of weathering combined with active uplift of the landscape for millions of years are driving forces behind the dominance of mass wasting.
Several rare plants are know to the BBA. Mt. Eddy draba (Draba carnosula) and Howells draba (Draba howellii var. howellii) occupy the high elevation rocky slopes, and cliff faces of the Siskiyou Crest. The Wiggins lily (Lilium pardilinum ssp. wigginsii) is found in meadows and the Washington lily (Lilium washingtonianum ssp. pururascens ) occupies the shrub dominated plant communities. An interesting liliaceous vine, English Peak greenbriar (Smilax jamesii) is occasionally found along high elevation riparian areas.
Habitat features of the area include meadows, alder thickets, and rock outcrops. The largest meadow in the area is Bear Meadow, supporting an array of native species herbs and grasses. Alder thickets lay on the landscape as linear features positioned on slopes and associated with perennial or empheral streams. Rock outcrops, including Bear Basin Butte, support colorful herbs such as cliff maids (Lewisia cotyledon var. cotyledon), rock pentstemon (Penstemon rubicola), pruinose Indian paintbrush (Castilleja pruinosa) and joint-leaved saxifrage (Saxifragopsis fragariodes).
Along with the diverse array of conifers, plants, habitats, and geology the Bear Basin Butte offers commanding views of the surrounding landscape. On the butte is an historical fire look-out and newly constructed cabin that are now available for overnight accommodations on a permit basis, for information contact the Smith River National Recreation Area. The primary road through the BBA leads to the Doe Flat trailhead, gateway to the Siskiyou Wilderness Area. Presently this trail is the only trail, however there are future plans to develop a trail loop starting at the butte. The two access roads into the BBA are gated during the wet months of winter and early spring to protect the area from vehicles readily transporting mud with the spores of Port-Orford-cedar root disease. These seasonal closures are an important tool to help reduce the chance of spreading the Port-Orford-cedar root disease into this pristine and still uninfected area.
The Bear Basin Butte Botanical is one of the six botanical areas on the Six Rivers National Forest established to protect unique botanical features of an area. The primary goal of these areas is to manage for species and habitat diversity as well as the natural processes that support these elements. Public use, education, and other activities need to be consistent with the values for which these areas were established.