Assessment - Southern Oregon Digital Archives

In the vicinity of the upper Powell Creek drainage, the soils are derived from shale and
altered basalt and are recognized as the Beekman gravelly loam, Vermisa extremely
gravelly loam, and Colestein gravelly loam. The main limitation for most uses of land
containing these soils is steepness of slopes.
Predominantly located in the southern part of the watershed, but also found in eastern
upslope areas near the mouth of Williams Creek, are soils that are formed mainly in
colluvium and residuum of granitic origin. These include Holland sandy loam, Barron
coarse sandy loam, Siskiyou gravelly sandy loam, Tetherick gravelly fine sandy loam,
Crannler very stony sandy loam, Goodwin very stony sandy loam and Rogue stony
coarse sandy loam. These soils are known for their erosion hazard. Sediment from these
soils can damage spawning beds by filling voids between cobbles and pebbles.
Within the USDA Soil Survey of Josephine County, there are seventy-one different soil
units represented in the Williams Creek Watershed. Also within the soil survey there is a
general soil map for Josephine County that provides an overview of the fourteen soil unit
associations that occur (NRCS 1983). A soil unit association is named for the most
commonly occurring soil in the group, which is named first. Eight of these are found in
the Williams Creek Watershed. A detailed description of these soil unit associations
appears in Appendix F.
Williams Creek Watershed Assessment 17