South Umpqua Experimental Forest
Introduction
The South Umpqua Experimental Forest was established on the Umpqua National Forest in 1951. It was
originally intended to provide research opportunities in the mixed-evergreen forest type common in the Cascade
Range of southern Oregon. Experimental watershed studies were undertaken on four watersheds tributary to
Coyote Creek by researchers in Corvallis in 1962. In 1967, the area of the forest was reduced in total area
from the original 1,921 to 263 ha of the Coyote Creek experimental watersheds.
Climate
Annual precipitation at the watershed #2 gauge from 1961 to 1976 averaged 1,230 mm and ranged from 880
to 1,560 mm, falling mainly as rain but with some snow in winter. During this period, annual discharge from the
control watershed averaged 630 mm.
Soils
Soils in the South Umpqua are derived from volcaniclastic bedrock and are moderately well-drained
gravelly loams to a depth of 150 cm. Both active and inactive large, slow-moving landslides have created
subdued topography in parts of the area, especially watershed 3.
Vegetation
The forest vegetation of the South Umpqua is characteristic of the mixed-conifer zone with Douglas-fir
intermingled with several pine species, incense-cedar, other conifers, and several hardwood species.
Long-Term Data Bases
Streamflow and climate records for the Coyote Creek watersheds are available online from the Forest Science
Data Bank associated with the Corvallis Forestry Sciences Lab (http://www.fsl.orst.edu/lter).
Research, Past and Present
The Coyote Creek experimental watershed studies of the effects of cutting and regrowth on hydrology and
sediment production have been the central feature of research on the South Umpqua. After gauging
commenced in 1962, watershed treatments were implemented in 1971, involving roads constructed in
watersheds 1, 2, and 3; watershed 1 was partially cut, watershed 2 had small patches cut, watershed 3 was
clearcut and burned, and watershed 4 was left as a control. Stream gauging and other studies were ended in
1981 but were restarted in 2000-01 in a cooperative effort of the Umpqua National Forest and Pacific
Northwest Research Station. A few studies of sediment production, ecology of mixed evergreen forest types, and
effects of forest cutting and regrowth on streamflow took place in the Coyote Creek experimental watersheds in the
early study period. The new period of stream gauging and sediment basin monitoring is intended to set the stage for
thinning and perhaps prescribed fire in the South Umpqua in the near future.
Facilities
The South Umpqua is located on the Umpqua National Forest’s Tiller Ranger District west of Tiller, Oregon, in
the South Umpqua River drainage. The forest has no facilities (other than roads, gauging stations, and
sediment basins) nor a web page, except for watershed research data on the Andrews Experimental Forest web
page (http://www.fsl.orst.edu/lter). The area is accessible via the National Forest System roads.
Lat. 43° 1' N, long. 123° 10' W
Contact Information
South Umpqua Experimental Forest
USDA Forest Service
Pacific Northwest Research Station
Corvallis Forestry Sciences Laboratory
3200 SW Jefferson Way
Corvallis, OR 97331
Tel: (541) 750-7355
http://www.fs.fed.us/pnw/exforests/south-umpqua/index.shtml
1Information has been updated since original publication.
pnw >
exforests >
South Umpqua
|