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I I I I I I I I I I I I I I I I I I I I miles downstream of this study's Channel Problem Area No.1. Transect 4 approximates the section line between Sections 13 and 14, Township 23 South, Range 54 West. Lindauer and Ward (1968:9) reported, "This stand type is almost pure salt cedar and is flooded yearly. A recent flood [either 1965? or 1966?], which raised the river level approximately 5 feet, covered almost 70 percent of the area of this stand. A few young cottonwoods 25-30 feet tall are scattered through the stand." They continue, saying "North of the river an extremely dense stand of salt cedar exists." and "About 1/3 mile west of line #4 a mature stand of cottonwoods can be found." (Lindauer and Ward 1968:9). Their vegetation types (Lindauer and Ward 1968:5-6) and transect line are marked on a 1965 aerial photograph (Lindauer 1970:25) that is exhibited as their Appendix X (Lindauer and Ward 1968:38). They also reported that deer, horses, and cattle had heavily grazed the area. The east section line for this same Section 13 (Township 23 South, Range 54 West) is also the Otero-Bent County line that Bittinger and Stringham (1963:25, Appendix II) utilized for their Transect No.7. Their report provided 1936 and 1957 aerial photographs from the U.S. Department of Agriculture as a comparison example of phreatophyte growth (Bittinger and Stringham 1963:1, 16, Figure 2). Transect 7 was 2,042 feet in length from which they took 4 vegetative samples (Bittinger and Stringham 1963:26, Appendix III, 29, Appendix IV). They categorized the 4 samples as Tree and Shrub Growth (Vegetative) Type III - dense brush and trees (Bittinger and Stringham 1963:4-7, Table 1). In their La Junta to Las Animas study area, Bittinger and Stringham (1963) reported that between the 1936 and 1957 aerial photograph years there had been flooding in the valley in 1942, 1944, 1947, and 1955 and that phreatophyte growth had averaged 47 acres per year between 1936 and 1947, and averaged 57 acres per year between 1947 and 1957 (Bittinger and Stringham 1963:1, 13, 15) In the Bent's Old Fort and Otero-Bent County line area, visual comparisons between the 1965 aerial photographs found in Lindauer and Ward (1968:38, Appendix X), the 1936 and 1957 aerial photographs found in Bittinger and Stringham (1963:16, Figure 2), and the 1998 aerial photographs provided by the Colorado Water Conservation Board found that vegetative composition in this area is also similar to that previously documented. Cottonwood and salt cedar have matured and salt cedar stands appear to be denser in 1998. Dense, new salt cedar growth was also evident on reshaped sand bars and along the river channel. Lindauer and Ward's (1968:9, Appendix X, 38) TranseCt Line No.4 is in the vicinity of the upper left-hand corner of Aerial Photograph 2 and Bittinger and Stringham's (1963:25, Appendix II) Transect No.7, at the Otero-Bent County line, is also in Aerial Photograph 2. The trend for increases in salt cedar expansion and density noted by Bittinger and Stringham (1963) in this area appear to be continuing. In Channel Problem Area No.2 (Aerial Photograph 3; (Figure 2), vegetation is not as dense as the other areas reviewed for this study. There are mature cottonwoods in the area and salt cedar growth is visible on sand bars, several stands of which are very dense. Scouring has occurred along the river margins in Problem Area 2 and is likely due to recent channelization efforts and flooding in recent years. Salt cedar does not appear to be a problem in flood flow conveyance or conveyance capacity at this time; however, as in numerous other areas in the valley, salt cedar should be controlled. 47