USFS/EPA Watershed Analysis Demonstration Project for Estimating
Existing and Potential Stream Shading

The Pacific Southwest Region developed a new methodology for assessing existing shade, from adjacent forest stand height and cover, as compared to potential shade along perennial streams as an alternative to direct stream temperature measurements. The project was funded by the Environmental Protection Agency to develop a process for determining current stream shade and demonstrating watershed recovery over time, as disturbed areas of forest re-grow and provide direct shading of streams. The 25,441 acre Pilot Creek 6th Order Watershed on the Six Rivers National Forest was selected as the study site within California because it is managed under the direction of Northwest Forest Plan, and is primarily National Forest ownership. The GIS and modeling procedures used life form, forest type, tree cover from above, and top story tree diameter attributes from a recent existing vegetation map derived from 30 meter TM and 5 meter Spot imagery. Forest Inventory and Analysis plots were used for deriving average site index and modeling existing and potential stand heights along buffered stream reaches. This analysis process is very cost effective and could be accomplished for determining stream shade conditions over larger stream networks, landscapes and watersheds for all National Forests, including private in-holdings, within the Northwest Forest Planning Area of California.