Consequently, samples with shrub or tree dominants (cover class 2 or 

 greater) were segregated hierarchically. The order of segregation was: 

 Populus deltoides , Fraxinus pennsyl vanica , Juniperus scopulorum , Shep- 

 herdia argentoa and associated ( Prunus virginienus , Cornus stolonifera , 

 Amelanchier ainifolia ) , Symphoricarpos occidental is , Artemisia tridentata , 

 and Artemisia cana . Samples with these dominants were separately clustered, 

 and the result compared with the original dendrogram. 



The classification resulted in recognition of twenty-seven community 

 types and one phase containing 452 (eighty-two percent) of the sample plots. 

 The remaining plots contained vegetation that was not recognized to form 

 discernable units repeated on the landscape, f^ore sampling may have re- 

 sulted in recognition of more types or other revisions. 



SPECIES COMPOSITION 



The species composition of the twenty-seven community types has been 

 summarized in a constancy and average coverage table (Appendix A). Con- 

 stancy refers to the percent of reconnaissance samples in which a species is 

 found for a given community type. Average coverage is based on absolute cov- 

 erage as taken from the midpoints of cover classes in reconnaissance samples 

 constituting a type. 



SITE DESCRIPTIONS 



Data collected in the vegetation reconnaissance were summarized for 

 form site descriptions for each ty^e. The data Are usually given in per- 

 centages by category or in means (X), standard deviations (s), and ranges. 

 Site descriptions will be useful in reclamation, especially if native 

 species are used. The Department of State Lands requires a discussion of 

 environmental factors for species and types. Site requirements for dom- 

 inant species can be inferred from these site descriptions. Unfortunately, 

 the soil series for the samples were not obtained. 



The only derived descriptor for each site is the slope-slope aspect 

 value. It is commonly recognized that slope aspect is of little descrip- 

 tive value if the slope is not also known. Stage (1975) describes a useful 

 index for combining both factors. 



The expression, tan (slope) (sin aspect + cos aspect), where slope 

 and slope aspect are measured in degrees, results in positive values for 

 cool aspects and negative values for warm aspects. Level ground results in 

 a value of zero. A slope of 45° is taken to be the coolest slope aspect and 

 225° the warmest slope aspect. This equation works well for the slopes en- 

 countered in the study area. 



By examining the slope-slope aspect value in conjunction with slope 

 values, one can determine whether a low mean slope-slope aspect value is the 

 result of low slopes and consistent slope aspects, or steeper slopes and ran- 

 dom slope aspects. The slope-slope aspect values, together with the soil 

 texture data are judged to be the most important site descriptors of those 

 evaluated. 



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