Large-scale aerial color photographs were used to evaluate trout habitat by studying stream and streambank conditions. Ninety-two percent of these conditions could be identified correctly on the color photographs. Color photographs taken 1 year apart showed that rehabilitation efforts resulted in stream vegetation changes. Water depth was correlated with film density: 76.4 percent on normal color film and 73.5 percent on infrared film. Shadow-length measurements of streambank vegetation height were 86 percent accurate. A technique to measure the degree of shade created by streambank vegetation is described. The cost of largescale color evaluation of trout habitat was estimated to be from $200 to $250 per mile of stream.

A method of stream habitat inventory using photo interpretation of large scale color infrared photography is described. The supporting methods of ground truth, targeting for aerial photographic identification and photo scale, film format exposure for water penetration of clear water, lens filers, and description of acceptable weather and sunlight conditions for optimum film exposure are identified.