Influence of Streamside Cover and Stream Features on Temperature Trends in Forested Streams of Western Oregon

Clearcut harvesting along low-elevation western Oregon streams with forest buffers (8.6 to 30.5 m wide) was followed by little direct local effect on water temperature. A study of 14 streams demonstrated that all have a tendency to warm with downstream direction even under full forest cover. After the natural warming trend of the stream water was accounted for, water at slightly higher temperatures within the buffered clearcut zones cooled to the trend line of temperature by 150 m downstream. Because of the natural warming trends in streams, estimating the net temperature effect associated with management practices requires use of a warming trend line as the norm for fully covered forests for each general level of discharge. West. J. Appl. For. 14(2):106-113.