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TABLE 2.04.10-20 C~ MEAN HERBACEOUS PRODUCTION AND PERCENT COMPOSITION (BY DRY WEIGHT) FOR THE MORPHOLOGICAL CLASSES ENCOUNTERED IN SAMPLES OF THE SWALE/DRAINAGE (SW) VEGETATION TYPE NEW HORIZON 2 PERMIT EXPANSION STUDY AREA, 1999 (n=50) GRAMS/PLOT PROD. PERCENT MORPHOLOGICAL CLASS 01 25M') LBSIACRE KG/HA COMPOSITION Perennial Graminoids 208.9 7,461 8,357 90.6 Perennial Forbs 21.7 775 868 9.4 Total 230.6 8,236 9,225 100.0 The willow component of the swaleldrainage type occurs on shallow, slightly elevated sites that are better-drained than areas supporting vegetation that can tolerate standing or flowing water, • and completely saturated conditions. No attempt was made to sample cover in the willow component because of the extremely high shrub densities encountered. Qualitative evaluation indicated that the canopy and ground cover, including litter, in the willow thickets was equal to or greater than 100 percent. In more open areas where the willows were less dense, quackgrass, alkali muhly and common spikerush were prevalent. The mean density of coyote willow, the only shrub species represented, was 78 stems per meter square. This translates to 312,000 stems per acre. The density of actual willows is expected to be much lower. It was impossible to tell which stem went with which individual and since willow is a clonal body individuals are in determinant. These density figures do not represent an average density for the swale/drainage type as a whole, but only in the thickets. A total of thirty species were found in the swale/drainage type. Graminoids dominated, with a total of twenty species (see Table 2.04.10-19) with ten having relative cover values of one percent or greater. Annual and perennial fortis totaled ten, only one perennial forb had relative cover greater than 1 percent. • (REVISED 8115100) 2.04.10 - 61