2015-04-29_PERMIT FILE - C1981008A (7)

Home Browse Search

located sample plots, although this species occurs in the graminoid component as scattered monotypic stands that range in size from approximately 0.1 to 2 acres. Eight species of perennial forbs occurred in the cover and frequency sample (Table 2.04.10-9). The dominant perennial forb was white prairie aster (Aster adscendens). This species comprised nearly one-half of the perennial forb cover and occurred in 50 percent of the cover plots. Only three species of annual forbs and one shrub species were represented in the samples. The mean herbaceous production in the graminoid component of the swale/drainage type is presented in Table 2.04.10-10. Individual plot data used to derive the summary may be found in Attachment 2.04.10-6, formerly Peabody 10-2 (Table 2-12). Table 2.04.10-10 expresses production on a dry weight basis by morphological class as grams per 0.25m2 (plot size), pounds per acre and percent composition by weight. The results indicate that perennial graminoids dominated the type component in terms of biomass (97.8 percent of the total above -ground plant biomass). Perennial and annual forbs contributed only minor amounts to total herbaceous production. Total production exceeded that of any vegetation type sampled (3,500.2 pounds/acre). The willow component of the swale/drainage 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. February 2015 JR -66) 2.04.10-38