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e e extended research period. Plants at the edge and downslope of an extended snowbank will increase growth somewhat due to the increase in moisture from the melt. However, this effect could be offset to a degree, or entirely, by decreases in soil temperature. During years within the average spectrum, no noticeable effects will occur. In other than average periods, some increase or decrease in plant growth may be detectable, but no change in composition would be expected.1I [8, p. 105, et seq.] )0 The Skywater Programmatic Final Environmental Statement reached the following conclusions with regard to short-term, research mode (random- ized) cloud seeding on herbaceous vegetation: ... liThe study situations encompassed seasons of naturally heavy and naturally light snowfall, and of naturally early and naturally late snow cover. In addition, artificial snow accumulations were deposited on portions of some study areas in both forest-meadow and alpine-meadow locations. Prelimi- nary results indicate that heavy or late-lying snow tends to shift the growing season to a later date, but not to affect its length. In delayed seasons, species were observed to complete their growth cycles and set seed. In the alpine setting, certain species subjected to artificial snowdrifts produced seed of reduced germinability. It is tentatively concluded that the Skywater experimental program of winter snowpack augmentation will have no discernable impact on herbaceous vegetation." [2, pp. 3-104, 3-105] The Skywater Programmatic Statement concluded: . . IINo significant impact on the overall productivity of the herbaceous community is expected. The main reason for this expectation is the finding that species composition is determined principally by minimum soil moisture during the growing season, and that productivity of different species in different settings is influenced by a variety of factors, including a slight delay in snow release data and a delay in the date of exhaustion of winter moisture. , - . "0ther outputs of the Skywater program such as instrument and equipment installations, travel, and seeding agents, are expected to have no significant impact on herbaceous vege- tation.1I [2, p. 3-108] Lana-term monitorina of the responses of veaetation to incremental pre~ipitation incre~ses will be reauirea to determine whether soecies comoosition and produc:ivity wi 11 be significantly affected. Studies of the effects of precipitation increases on large and small ~ammals were undertaken in the Medicine Bow Ecoiogy Project [14J, the Sierra Ecology Project [15], and the San juan Ecology Project [10]. In addition, Montana State University surveyed previous research on the 17