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1 • each of the two reference areas. Acreage weighting these reference area values does not resuR in any change to these findings. Only the second criterion is met. The first, third, and fourth comparisons fail. Rewmmendatlons / It is recommended by Cedar Creek that resolution of the diversity evaluation difficulties be corrected in three steps. First, because the native reference areas cannot pass the established standards, it would seem that such standards were set inappropriately for site-specific conditions. Therefore, a more appropriate diversity standard must be developed. Based on data collected from the two reference areas, 1 Cedar Creek would suggest replacement of the current diversity success criteria with the following: ~' One perennial grass species or one perennial shrub species-with-> 3% relatve cover. '~ ~ • Total perennial warm season grasses with > 3% relative cover or one additional perennial species with > 3% relative cover. - 1 a • No reclaimed area shall have a single species that represents > 70% relative cover. Rationale for the above changes is as follows. First, much of the project area exhibits site-specific conditions conducive to the development of salt-desert scrub communities that heavily favor drought- 1• tolerant shrubs over herbaceous species. Such communities in this portion of Colorado tend to exhibit poor diversity values (e.g., Mancos shale areas often exhibit sparse cover by only a single species). Portions of the project area exhibit conditions somewhat conducive to establishment of herbaceous species /communities, but these are limited to north and easterly facing aspects. Where herbaceous 1 species can establish and persist, warm season taxa should be represented owing to both the amount and timing of precipitation expected in this area. Finally, given that cheatgrass is a well~stablished component of the native community, the limitation that a single taxon cannot exceed 40% of the composition is unrealistic (see values for cheatgrass on Table 6). Therefore, this value has been 1 increased accordingly. Furthermore, dominance by a desirable taxon such as four-wing saltbush is far more preferable than dominance by an undesirable taxon such as cheatgrass. A second recommendation would involve changing the comparison procedure to allow for the option 1 of an acreage-weighted comparison. Such a comparison would tend to eliminate certain difficulties inherent with "micro-management" of revegefated areas. To effect this change, the language on page 14- 22 (last paragraph -first sentence) of the permit should-be changed to read-as follows:- - _ ___ . 1 "Determination of revegetation success will be based upon sample data comparison of reclaimed areas • with reference areas", and will include the option of utilizing an acreage-weighted comparison procedure _ acro ge portions. or even the entireri. of reclaimed surtaces. - -~ ~~ . j ~~-o o ~ /S Page 9 ~w~ o~n i