The 280 ha Three Creek RNA is located in the central Cascades, approximately 21 air miles east of Sweet Home in Linn County, Oregon. The RNA is comprised of north-facing glacial cirques, which form the two main drainages that make up the headwaters of Three Creek. The topography is generally steep, and high cliffs, formed by glacial action and massive slumping, run east-west through the middle elevations of the RNA. Elevations range from 1122 m to 1638 m. Moist, protected glacial cirques contain a forest mosaic of Alaska cedar, Douglas fir (Pseudotsuga menziesii), and Pacific silver fir (Abies amabilis); some trees are 800 years old. Sedges and wet site forbs dominate two wet meadows located in the cirque in the southern portion of the RNA, and Sitka mistmaiden and threeleaf lewisia can be found on nearby rock outcrops. Elsewhere in the RNA Tsuga heterophylla (western hemlock), Douglas fir, and noble fir (Abies procera) dominate the lowest elevations. The highest ridge tops are dominated by mountain hemlock (Tsuga mertensiana). Non-forested shrub communities are prominent on talus slopes and cliffs. Drier sites in these areas are either dominated by vine maple (Acer circinatum) or are unvegetated, while moister sites are dominated by vine maple, Sitka alder (Alnus viridis ssp. sinuata), devil's club (Oplopanax horridus), and stink currant (Ribes bracteosum). The northern spotted owl, a Federally listed threatened species, has been spotted in the RNA.

Township/Range/Section:

Parts of secs 18, 19 and 20, T14S, R5E, and a portion of section 13 in T14S, R4E.

Latitude:

44,20N

Longitude:

122,15W

Quad Map:

Tidbits Mtn. and Carpenter Mtn.(7.5), Oreg. cover the western and eastern halves, respectively.

Threatened or Endangered Species:

Confirmed sightings of, and suitable habitat for, the northern spotted owl. Two plant species on the OR Natural Heritage Review List are Douglasia laevigata and Castilleja rupicola.

Exotic Species Present:

Lactuca muralis has been seen and pulled. More are likely present.

Plant Communities:

The area includes an old-growth Douglas fir-Pacific silver fir forest in near climax condition, an Alaska yellow cedar forest mosaic, and the headwaters of Three Creeks.

Aquatic Features Present:

The Three Creek headwaters is within the RNA.

Soils:

There are six soil mapping units occur within the RNA, representing seven landtypes including the following: 1) Rock outcrop, andesites and basalts 2) Talus, rock outcrop, avalanche chutes, and low-site timber 3) Wet non-forest land 4) Loamy-skeletal, mixed Dystric Cryochrept 5) Loamy-skeletal, Entic Cryumbrept

Other Physical Features:

Massive rock cliffs

Past Disturbance History:

A fire lookout cabin was located on the southern peak of Twin Buttes, but was removed in 1986.

Other Comments:

Access by road