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Section 785.19 (c) Continued. • ridge to the right of the bright red area are another good example of coarse texture. The dark green areas in the central portion of photograph number 359 are big sagebrush stands and are examples of fuzzy texture. Location relative to elevation and drainage features is important in predicting soil conditions and associated vegetation. Within floodplains, even slightly elevated land may support different plant communities than that of the surrounding plain. Using a stereoscope to achieve a three dimensional view of the subject area enables the interpreter to make elevation determination. At the scale of these photographs, three dimensional relief can be de- tected for objects such as trees of about 6 to 8 feet in height. Channels in drainage bottoms with an elevation difference of 2 to 3 feet can be detected. u The first of the six subject areas, the Illinois River floodplain, was not analyzed due to the fact that CIR coverage is not avail- able. The Canadian River is the second subject area. It appears as a reddish-green area about an inch wide arching across the upper half of all three photographs. The river is the black meandering line (flowing to the north) occupying the lower boundary of the subject area. When viewed in stereo, the active floodplain (measuring about ''L to '~ inches wide) is isolated from the hay fields to the north by an embankment or gently sloping bluff and from the high sagebrush ground to the-south by a relatively steep bluff. Trees can be seen immediately adjacent to the river channel, appearing as small red bumps protruding upwards. Two areas in the active flood- plain (the central 1/3 of photograph 358 and the left 1/3 of 359) have been cut for hay as evidenced by lighter colors, greenish in 358 and pinkish in 360, and by linear or striated patterns result- •785-23