2022-10-26_PERMIT FILE - C1981041

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pratensis). This years sampling of the new reference area identified two annual grarrrinoids . (Bromus tectorum and Eremopyrum tr{t{cc~um) as well as four perennial grasses (Arist{da purpurea, Hilaria jamesii, Oryzopsis hymenoides, and Sporobolus cryptandru;r). Cover sampling of the original greasewood reference area in 1983 revealed six forb species that provided 17.8 percent of the cover. Of the five forb species encowntered, three are generally considered weedy invaders (Cardaria draba, Descurania Sophia, and Lepidium perjoliotum). Forbs did not contribute greatly to the ne~v reference area cover, however, Plantcrgo patagonica is indicative of relatively undisturbed azeas. Sarcobatus vermiculatus was the major woody species in the original greasewood reference azea. Chrysothamnus nouseosus and Tamarix ramosissinra (tamarisb<) were also present to a lesser degree. Within the new greasewood reference area, six woody species were represented in cover sampling this year. Sarcobatus vermiculatus remained the dominant shrub, with a diverse assemblage of other species ranging from Chrysot{ranrnus viscidiJlorus (rabbitbrush) to Artemesia tridentate (big sagebrush). Tltis is again indicative of elevation and a more native condition in the new greasewood refe:renct: area. Herbaceous Production Herbaceous production sampling in 1983 from the original greasewood reference area yielded a total mean value of 50.1 g/m2 or 446.5 pounds/acre. Forbs dominated the • herbaceous production with a mean of 30.5 g/m2 (271.8 pounds/acre). Graminoids provided 19.6 g/m2 (] 74.7 pounds acre) in the ] 983 sampling. In the new greasewood reference area, total herbaceous production was nearly twice that of the original greasewood reference azea (83.5 g/m2 or 744.3 !b/ac). Graminoids provided 96.7 percent of the herbaceous production in the new reference area, though 65 percent of the graminoid production was the annual Bromus tectorum. The low herbaceous production level in the original reference area can be attributed to the dense overstory of Sarcobatus vermiculatus which effectively shades out understory species. Overall, the new reference azea provides a more open environment with greater herbaceous production. Woody Plaot Density Two woody plants were encountered in the 1983 sampling of the original greasewood reference area, Sarcobatus vermiculatus and Chrysothamnus nauseous. Total woody plant density in 1983 was 28.5 Gve stems/SOmz or 2314.9 Gve stems/acre. Sampling of the new greasewood reference area identified a woody plant density of 37.32 live stents/SOrr~ or 3020 Gve stems/acre this year. Eight woody species contnbuted to the woody density of the new reference azea. Sarcobatus v~srmiculatus was the most dense woody plant in the original reference azea, contributing 21.5 Gve stems/SOrt>z (1748 Gve stems acre). In the new reference azea, the small shrub Gutierrezia sarothrae was the most prevalent woody plant with 18.22 Gve stems/SOm2 1.1475 Gve stems acre). Sarcobatus vermiculatus was the most prevalent tall shrub in the new reference azea, contributing 9.26 Gve • stems/SOmz (749.5 Gve stems/acre). Remaining woody density at the new greasewood -8-