2009-08-13_PERMIT FILE - C1981019A (3)

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number of seeds per square foot, from 29.2 / ft2 to 75.1 / ft. Much of the increase is due to the substantial increase of sagebrush seed from 0.02 pounds PLS/acre to 0.5 pounds PLS/acre. Although inclusion of sagebrush seed is contrary to the intended vegetation community that targets the grazingland land use, this change has been adopted to increase the potential for development of shrub patches within the grassland community as well as to add structural diversity to the community and overall reclaimed area. If too much sage results from this mix for the intended land use, the amount of sagebrush seed can be reduced. If excess shrub numbers result from early revegetation efforts, then managerial techniques are readily available to reduce sage populations once the land surface has been transferred back to the landowner if Colowyo does not choose to reclassify the area as sagebrush steppe and apply for bond release under those criteria. Table 2.05-8, List of Contingency Substitutions for Table 2.05-7 and Table 2.05-9, provides the approved list of contingency substitutions for the seed mixes should certain taxa be unavailable or unwarranted in any given year. The reclamation seed mixture for areas targeting sagebrush steppe (wildlife habitat land use - sage grouse brood rearing habitat), as shown in Table 2.05-9, Reclamation Seed Mixture, also contains sufficient diversity for ecological stability. This mixture contains a variety of grasses, forbs and shrub species well adapted to the soil and moisture conditions found at Colowyo and should provide both the structural diversity and life form diversity necessary for habitat requisites of young sage grouse. The seed mixture is capable of self-selection for each reclaimed micro-habitat encountered in the reclaimed areas and contains sufficient sagebrush seed to hopefully encourage at least some emergence each year and substantial emergence occasionally. There is potential, that too much sagebrush seed (115 seeds / ft2) has been incorporated into this mix, and given recent experience with new planting techniques designed for use at Colowyo in and after 2008, the amount of seed may need to be adjusted at some future point*. However, present knowledge within the industry dictates that a significant amount of sagebrush seed is necessary to consistently obtain desired emergence. Present knowledge also dictates that special care must be taken to plant sagebrush seed at precisely the correct depth (-1/16th of an inch) and at precisely the correct time of year (immediately prior to the first major snowfall event of the Fall). The greater the attention given to such details, the greater the potential for successful emergence. As with the reclamation seed mixture for grassland areas, the species and seeding rates indicated on this sagebrush steppe mix resulted from in-depth analyses of past mixes and the resulting emergence and dominance within revegetated areas. Furthermore, it is anticipated that the reduced competition from grasses, especially sod-formers like thickspike wheatgrass, will result in elevated diversity and better performance from certain poor producers such as big bluegrass, Rocky Mountain Fescue, Louisiana sagewort, bitterbrush, and Wood's rose. If performance of any of these taxa remains poor after additional attempts, they would be candidates for removal from the mix. Because the amount of grasses (and all sod-formers) has been substantially reduced for this . By example, as of 2007 the CSU shrub test plots exhibited an average sagebrush population of 3,500 plants per acre. This population resulted from an initial 0.25 pounds PLS of seed in the mix, following an excellent recruitment year. 2.05-51 Revision Date: 3/14/08 Revision No.: TR-72