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<br />of disease and insect attacks. Therefore, the most effective <br />monitori ng and research program woul d be one that concentrates <br />on determining: (1) the success of the augmentation, (2) the <br />effect upon snowpacks under various environmental complexes, and <br />(3) the effects of different climatic influences upon insect and <br />disease incidence. <br /> <br />"Item 3 is a research recommendation that goes beyond the impact <br />of weather modification. It involves the basic impact of all <br />forms of climatic influence upon forest diseases and insects. <br />This encompasses microclimatic influences which occur as a <br />result of forest fires, the creation of openings in forest <br />stands due to natural causes, forest harvest operations, grazing <br />by wil d 1 ife and domest i c stock, and any other ch ange to the <br />climatic and cover conditions existing at any point in time and <br />space." [15, pp. 1-31 to 1-34] <br /> <br />The Sierra Cooperative Pilot Project Environmental Assessment states: <br /> <br />"With regard to precipitation, it is generally believed that the <br />average annual rainfall is the basis for the species composition <br />of an area; and that it is the end of the curve (the drought or <br />below-average situation) that determines whether a given species <br />will continue in an area. Shifts in moisture through the middle <br />range of moi sture avail abil ity wi 11 affect growth and biomass, <br />but do not have a controlling impact on composition of the plant <br />commun ity. <br /> <br />II It woul d requi re a significant increase in moi sture supply over <br />a middle- to long-term period in order that competing plants <br />would invade an area and push existing species out. <br /> <br />II Small shifts in speci es may occur due to 1 ate-lyi ng snowbanks <br />at small, localized sites if the wind and other snow-depositing <br />controls extend the same snowbank each season during an extended <br />research period. Plants at the edge and downslope of an <br />extended snowbank wi 11 increase growth somewhat due to the <br />increase in moisture from the melt. However, this effect <br />could be offset to a degree, or entirely, by decreases in soil <br />temperature. During years within the average spectrum, no <br />noticeable effects will occur. In other than average periods, <br />some increase or decrease in plant growth may be detectable, <br />but no change in composition would be expected." [8, p. 105, <br />et seq. ] , <br /> <br />The Skywater Programmatic Final Environmental Statement reached the <br />following conclusions with regard to short-term, research mode <br />(randomized) cloud seeding on herbaceous vegetation: <br /> <br />liThe study situations encompassed seasons .of naturally heavy <br />and n at u r all y 1 i g h t s n 0 wf all, and 0 f n at u r ally ear 1 y and <br />naturally late snow cover. In addition, artificial snow accum- <br />ulations were deposited on portions of some study areas in both <br /> <br />16 <br />