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The tree seedGn~noted were a mixture of Pinyon Pined Douglas Fir. Unlike the tree plantings on the main quarry access roadside disturbances, Douglas Fir on this site survived almost as well as the Pinyon and actually had a proportion to the Pinyon Pine similar to the proportions planted. This means that Douglas Fir seedlings can survive on this slope essentially as well as Pinyon Pine, if not better. Whereas on the roadside disturbances the Douglas Fir plantings were almost a total failure and Pinyon Pine survived in large numbers, along with Rocky Mountain Juniper. Why this difference exists, cannot be directly determined. This site is west facing and should be hotter and drier than the north facing slopes along the quarry access road. It could have something to do with the nature of the soil microbiology. That is, if Douglas Fir is quite sensitive to soil microbiology (some literature does indicate this may be the case), it might fail to survive on the roadside disturbances where the microbiology has been very severely disrupted. On the other hand, it might do quite well on this site where the primary damage was to the surface vegetation and the soil microbiology was only slightly affected. It could also be related to the amount and type of organic matter present, which would also relate to microbiology. At least a half dozen of the trees that had been severely damaged but not uprooted by the rolling boulders, have developed significant regrowth. The regrowth is developing rapidly and appears to be very healthy. It is expected that these damaged trees will eventually develop into full size trees, but due to the damages inflicted by the rolling rocks, these trees will have an unusual form. Most of the depressions created by the rolling rocks are well vegetated with grasses and some of them have shrubs beginning to encroach into the disturbance. Only the larger ones are still very evident. Another year or two of growth will obscure those. No headword erosion was seen in any of the depressions. Grass growth in all disturbed areas on the slope is excellent. Only the very rocky scree slopes, none of which were produced by the rock spillage, show weak growth. The grasses covering the slope are a nice combination of those that were planted and the native species. No locations were seen that contained grass growth that was intensely dominated by the seeded grasses. Although to a botanist the grass community on the slope would exhibit a slightly artificial character, to the layman the blend of introduced and native grasses would look quite natural. No photographs of the initial condition of the site were taken on the inspection, but it appeared that the shrub cover had increased significantly in the last two to three years. This could be an illusion produced by the much more dense grass growth around the shrubs. Photographs were taken for comparison with earlier images. It would be expected that in time shrub cover would increase significantly due to the reduced competition from trees. This competition primarily came from the shade factor produced by the trees and competition for water. With the removal of the trees, more resources are available for the shrubs. The rate at which this increase in shrub cover would occur, however, cannot be predicted with accuracy. Therefore, any real increase in shrub cover will need to be determined by comparison to the previous photographs. Page 2 of 3 1992 Annual Report Supplement M-77-210 Snyder t2uarry