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5 Several types of control of phreatophytes through chemical means have been examined, among them herbicides, defoliants, and anti-transpirants. Although the treatment of phreatorhytes by chemicals shows some initial promise, there are some i'roblems associated with chemicals which have not yet been solved, among them pollution of the nearby water and land. Spraying on a regular basis is also necessary to maintain phreatophyte control. Combinations of various control techniques have been studied, includ- ing the grazing of mowed areas. One particular example, hOYlever, illustrates 8 ~he problems of long-term phreatophyte control. In this case, the salt cedar "as mmved to a height of 12 inches and the area was then subjected to heavy grazing. By the second year after mowing, despite the heavy grazing pressure, the salt cedar had regrown and become so dense that cattle would no longer enter the area. Assuming that a complete phreatophyte control program would be possible, approximately 80,000 acre-feet of water might be salvaged in the Arkansas Basin in the first year at an approximate clearing cost of $2,000,000 to $4,000,000. This initial clearing cost would, by necessity, have to be repeated regularly. The indirect costs would also have to be considered. A proposal made in 1968 by the Army Corps of Engineers to lessen the amount of water lost to phreatophytes in the Arkansas River would have \Vorked On a basis of denying the phreatophytes water. This \Vould have been accompl ished by Im,ering the channel of the river. This plan has met with considerable public resistance, even though it was claimed by the Corps of Engineers that imple~entation of this plan \Vould have decreased the loss of water to phreatophytes by 80 percent. - - 1-'