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1 <br />' <br /> by a large number of Chrysothamnus nauseosus seedlings, which contributed to total <br /> cover (and woody plant density). <br />' <br /> Bromus japonicus/tectorum accounted for the majority of cover by individual species in <br />' all Test Plot 1 treatments. Several perennial grasses were present in all treatments, <br />with .~ropyron cristatum and ~gropyron smithii representing the cool season species, <br /> and fiilaria jamesii and Sporobolus airoides representing the warm season species. <br /> Mirroring the general graminoid cover trend, these perennial species showed increasing <br />' cover to the 24" treatment depth. Perennial graminoid numbers were lower on the 48" <br /> treatment than on other depth treatments in Test Plot 1. All annual forts were <br />' characteristic of open and/or disturbed areas. No single species was singularly <br /> predominant. Woody plants were represented by four different species in the Test Plot, <br /> with no single species predominating in all treatments. <br />1 <br /> Test Plot 2 cover values (Tables 11, 13, 15) showed lifeform cover trends similar to <br /> Test Plot 1. Graminoid cover increased from 6" to 12" treatments (26.8% to 36.0%) <br />' and decreased in the 24" treatment (28.0%), again coincident with a decrease in <br /> Bromus japonicus/tectorum cover (23.6%). Annual forb cover was variable with the <br /> 24" treatment plot having the highest cover (5.2%), 12" the lowest (1.2%), and 6" <br />' intermediate (3.2%). Woody plant cover showed a distinct increase with soil depth. <br /> The 6" treatment had 1.6% cover, the 12" treatment 3.2% cover, and the 24" treatment <br />' plot had 14.0% total woody plant cover. <br /> The species dominating the cover in Test Plot 2 was Bromus japonicus/tectorum. <br /> Agropyron cristatum, Agropyron smithii, Elymus junceus, and Sporobolus airoides <br />' represented the perennial grasses in this Test Plot. Test Plot 2 did not have the <br /> consistent variety of perennial grass species that Test Plot 1 did. Perennial grasses <br />' increased in cover with increasing soil depth (1.6%, 2.0%, 2.8% for ,~ropyron <br /> cristatum). Annual forts species were present in decreased number in Test Plot 2 also. <br /> Lower species representation in Test Plot 2 may be a result of the western aspect and <br />' it's accompanying xeric moisture regime. Atriplex confertifolia found Test Plot 2 <br /> conditions favorable, increasing in cover from 1.2% on the 6" treatment to 10.4% on <br /> the 24" treatment. Since Atrip/ex confertifolia is an inhabitant of xeric azeas in the <br /> western states, this may provide additional indirect support for the lower species <br /> representation alluded to previously. <br /> Test Plot 3 showed the highest cover values (by treatment) of the Test Plots (Tables 17, <br /> 19, 2l ). The predominant reason is the high cover of Bromus japonicus/tectorum. <br /> Cover for this species ranged from a low of 26.4% on the 6" treatment plot to a high of <br />' 42.4% on the 24" plot. Total graminoid cover showed an increasing trend with <br /> increasing soil depth. Fort cover did not show a consistent trend with increasing soil <br />' depth. Speculation on a competitive interaction between Bromus japonicus/tectorum <br /> and forb species is not borne out by close examination of herbaceous production data <br /> from this Test Plot. <br />' 49 <br />