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w W CD o colluvium; and, 3) dissected Mancos shale uplands. Some of the geologic or soil forming materials were identified in several geomorphic units - cutting across geomorphic boundaries. A vertic-like swelling soil was mapped both on the low pediment and on dissected shale surfaces. The data suggest that the parent material for these soils is probably aeolian or windblown in origin,as it occurred on both the low flat areas and along the southern and eastern sides of the outcrops; it also lacks rock fragments and was noticeably silty or very fine sandy loam in texture. Eleven different soil series in 22 mapping units were recognized in the Woodsite site (Schafer, 1981). Few of these series were established during the Soil Conservation Service inventory of the area. The series identified during the detailed survey were named for the purposes of the survey (Table 1). Torriorthents varying in depths and texture were the most common soils en- countered. The soil series were delineated partially on the basis of the depth to bedrock or para1ithic horizon. The para1ithic contacts, described as CR horizon herein, and shale were defined as that point where more than 50% gf the shale was retained on a 2 mm sieve after one minute of shaking. Slightly weathered shale (R horizon) was defined as a depth where 5% or less of the material passed a 2 mm sieve and shale fragments averaged over 1 cm in thick~ ness. In many instances, a prominent accumulation of salts and gypsum oc- curred just above the R horizon or the CR horizon, forming a Ccs or Cca 1 ayer . Vegetation Resource Inventory: A literature review was included in the vegetatlon lnventory study. The more significant papers reviewed include that of Ibrahim (1963) and West and Ibrahim (1960) which discuss the soil and vegetative relationships of plant communities developing on the Mancos shale of southeastern Utah. In those studies, they identified and described four edephical1y controlled climax plant communities on the Mancos shale. The communities identified included: Atrip1ex confertifo1ia/Hi1aria jamseii, Atrip1ex nuttal1ii/nutta11i/Hi1aria jameseii, Atriplex nutta11ii gardnerii/ astor zyloriza and Atrlplex corrugata. Lusby, et al. (1963) in a hydrologic study identified Sarcobatus vermicu1atus as a dominant on the lower part of the main drainages, Atrtip1ex currugata as occurring on alkaline flats in the upper reaches of the dralnage basins, Artemesia tradentata and cr~sothamnus nauseosus on alluvial soils along the drainages, and Atriplex con ertifolia and Hil ari a jamsei i on upland sandy soil s. Branson et al (1976) stUdi ed several sOll factors affecting the geographic distribution of salt desert shrubs. He concluded that the soil moisture relationship was the primary factor affecting distribution of salt desert shrubs. Soil soluble salts appear to be an important cause of community differences. Plant communities occurring on soils with the highest osmotic stress are dominated by Atrip1ex nutta11ii. Communities dominated by Atri,lex confertifolia, Sarcobatus vermicu1atus, and Eurotia lanata have soi s with decreasing osmotic concentratlons. An initial reconnaissance study of the site was made in July 1981, where tentative community types were identified. Representative sampling sites were then selected. Sites were sampled as follows: 13 % ~ . ~ "'- ~,>~" '''--'' .'.'