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6 The consequences of clearing phreatophytes are as yet not completely evaluated. Certainly some of the results of clearing would be of a nature that would work against the salvage of water. Among these would be an increase in the temperature of the water and soil formerly shaded by the phreatophytes, and a rise of the water table of the banks surrounding the watercourse, both of which would increase the loss of water to evapora- tion and transpiration. Other consequences would also be ex~ected, includ- ing increased erosion of the soil formerly held by phreatophyte roots by wind I I and water. Vegetation barriers, for instance, can protect against the wind erosion of soils for distances nine to twelve times their hei~ht. 3 Some more obvious changes would be the 'effects of a radical change in the environment of the different types of wildl ife which reside in phreato- phytic areas. The removal and control of phreatophytes would certainly caUse a dramatic alteration in the I iving habits of many species. Aesthetic considerations must also be taken into account in any evaluation of phreatophyte control. As phreatophytes are often the most noticeable vegetation in a rather barren area, phreatophyte control is bound to have significant emotional impact because of its aesthetic impor- tance. As inroads are made further and further into natural areas as a result of man's aClivities, resources such as certain phreatophyte vege- tation wi II become increasingly important. The effect of phreatophytes upon sedimentation in rivers is large. Typically, the phreatophytes obstruct, an,~ SIOl", the flo>! of water, thus causing a large .proportion of the sediment bein9 carried. dO\.vnstreilnl to be depositecJ, This has consequences for reservoirs, ~.Jhich, in many cases, \'Y'ould llsi It up"more Lj.Jic:""Jy if upstre<1,;J phreatophytes \",'ere removed. r