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• Cover
<br />Total absolute vegetation cover averages 68.9 percent. Bare soil
<br />is 12.0 percent, and litter and rock average 14.2 and 4.9 percent, respectively.
<br />Cover by fifeform is as follows: shrubs and subshrubs--47.4 percent, perennial
<br />graminoids--9.9 percent, perennial forbs--B.2 percent, trees--1.1 percent,
<br />annual forbs--1.0 percent, succulents--0.9 percent, and vines--0.4 percent
<br />(Table 151.
<br />Shrubs and subshrubs account for 64.6 percent of the vegetative
<br />cover. Gambel oak is the dominant species with 39.7 percent absolute
<br />cover. Common species are true mountain mahogany 13.0 percent), big sagebrush
<br />(2.6 percent), squaw-apple (0.6 percents, Oregon-grape 10.5 percent), and
<br />cliff fendlerbush 10.5 percent). Less common species include rubber rabbit-
<br />brush, broom snakeweed, common chokecherry, and skunkbush sumac.
<br />Perennial graminoid cover is relatively high, contributing about
<br />19 percent of the vegetative cover. Major species are intermediate wheatgrass,
<br />an introduced species with 2.1 percent cover; needle-and-thread with 1.6 percent
<br />cover; squirreltail with I.3 percent; Indian ricegrass with 1.3 percent; and
<br />mutton bluegrass with 1.0 percent. Minor species include, in descending order,
<br />red threeawn, elk sedge, side oats grams, Kentucky bluegrass, western wheat-
<br />grass, blue grams, and prairie junegrass.
<br />• Perennial forb cover is also relatively high, comprising 11.4
<br />percent relative cover. Common species are hairy goldenaster 12.0 percent),
<br />toadflax penstemon (1.3 percent), Louisiana sage 11.0 percent), pingue 10.9
<br />percent), stemless actinea 10.6 percent), and slimflower scurfpea (0.6 percent).
<br />Minor species are, in descending order, showy goldeneye, western yarrow
<br />lAchiddea m<!.le~o~lium), scarlet globemallow, redroot eriogonum, and Fendler
<br />rockcress IA~aGi~ ~endle~,i 1.
<br />Tree cover is low, averaging only 1.6 percent relative cover.
<br />Pinyon pine and Utah juniper average 0.6 and 0.4 percent absolute cover,
<br />respectively.
<br />Annual forb cover is low. The more common species are trailing
<br />fleabane Ifici~.eaon ~.lo~.e.~~la~ti~l, spreading erigeron, yellow sweetclover, and
<br />purple-white owlclover.
<br />Succulent cover is low, composed of New Mexican yucca and plains
<br />pricklypear. Vine cover is also very low, composed of hairy clematis
<br />lC.lema.ti~ hia~u.ti~aimal. Other minor plant species found in this vegetation
<br />type are listed in Table 15.
<br />Production
<br />Total production in the Mountain Shrubland reference area averages
<br />52.1 g/2 m2 or about 260 Ibs/acre. Perennial forbs comprise about 54 percent
<br />of the total (28.1 g/2 m2). Perennial graminoids produce 22.6 g/2 m2. The
<br />• major graminoid species are, in descending importance, mutton bluegrass,
<br />-14-
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