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<br />3604 <br /> <br />13 <br /> <br />. <br /> <br />Both upland and wetland veRetation in the San Luis Valley and the <br />Closed Basin have been studied for many years. A 3-year growth study <br />was conducted by the Bureau of Reclamation on hasically uoland vegeta- <br />riao. The study area was located whpre the water table was Inwered by <br />a pilot salvage well. rhe study has shown that shrubs right ar0und <br />~roject salvage wells will be adversely affected. Most of the shrubs <br />within several hundred feet of the well will oe smaller in size and <br />fewer in number after several years of project operat ion. Younger <br />shruhs ~ill most likely survive even near the wells. These shrubs hav~ <br />the ability to follow the water table down as they continue to utilize <br />surface precipitation. Older shrubs do not respond to rainfall as <br />well. <br /> <br />The reaction of saltgrass and wiregras8 to a lowering water tahle is a <br />little more conplicated. Where the water table is more than 5 feet <br />down, mo~t grasses depend on direct rain and snowfall for annllsl <br />growth. In these areas, project pumping and lower water tables will <br />not affect the ~rasses. In areas where a very high water table does <br />support stands of grass, lowerLng the water table will result in fpwer <br />grass plants. Lower water tables and fewer saltgras5 plants will allow <br />other grass species native to the ar~a to increase. Grasses cOQing <br />into th~ area will De more valuable to liv~stock grazing. These <br />grasses will ~~ able to compete because of decreased surface salt accu- <br />mulations. Less desirable forage plants (saltgrass and wiregrass) will <br />share space with more desirable grasses (alkali sacaton, blue grams, <br />and westerll wheat). <br /> <br />There will ~e some reduction in plant vigor in wetland areas as a <br />direct result of pr0ject pumping. Federal 18\/ requires the replacement <br />of affected IJetlands. The project will deliver water to the existing <br />Blanca Wildlife Habitat Area and Alamosa Wildlife Refuge. A new <br />wildlife habitat area will be developed in the Russell Lakes vicinity. <br />A recreation ar~a will be established in the San Luis and Head Lake <br />area. These steps \/ill maintain both the overall quality and extent of <br />wetlands in the San Luis Valley and the Closed Basin sump ares. These <br />steps \.,I'i11 more than conpensate for any wetland vegetation loss <br />resulting fro~ project pumping. <br /> <br />Preliminary studies suggest that a program of establi~hing stabilizing <br />vegetation around salvage wells and the main canal should greatly <br />reduce long-terln project maintenance costs. Shelter belts of trees and <br />starting stands of native grass in bare areas are being studied for <br />inclusion as part of the pr0ject design. Applying small amounts of <br />project salvage wateT fOT a ShOTt time after planting should allow <br />native plants to get well started. This program should result in a <br />significant increase in vegetation over preproject conditions in the <br />areas of the salvage wells and main canal. <br /> <br />To sum things up, the direct effects of the project operations on <br />plants will oe neither widespread nor severe. Vegetation effects will <br />occur only within the project boundaries. Visibly less vegetation may <br />result within 1,000 feet of some salvage wells. At distances farther <br />away from the well., the change in vegetation (if there is any) will <br />only show up in careful scientific studies. <br />