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Downstream, Lindauer and Ward's (1968:9-10, 39) Transect Line No.5 is located about 2 miles east of Las Animas approximating the sectiollline between Section 6, T23S, R51 Wand Section 1, T23S, R52W, and as shown on the Lindauer and Ward (1968:39) aerial photograph designated as Appendix XI. Transect 5 is located in this study's Channel Problem Area No.3, and is upstream of the confluence of the Purgatoire River. Transect 5 is located near the lower center of Aerial Photograph 6. They reported that vegetation on the south side of the Arkansas River was more variable than on the north. Salt cedar dominated scattered cottonwoods and a few willows were present (Lindauer and Ward 1968:9-10). They noted that in the late summer there was an abundance of sunflowers, some reaching 10 feet in height, and that considerable flood deposition was observed in the area,saying thl\t a flood in July 1966 [sic ?, or possibly 1965] influenced the surrounding flood plain considerably. There was a dense stand of salt cedar on the north side of the river that was interrupted by small water channels near the river. North of the salt cedar stand was a large expanse of alkali sacaton and the area had little evidence of grazing (Lindauer and Ward 1968:9-10). Their "expanse of alkali sacaton" is an area of high ground that is shown as lighter colored vegetation on the north side of the river in the center of Aerial Photograph 6. The floodplain north of their "expanse" is again inundated with surface water and extensive cattails. . Bittinger and Stringham's (1963:25, AppendIx ll) Transect No. 18 is located on the section line between Sections 2 and 3, T23S, R52W, which is located at the State Highway 50 bridge north of Las Animas (Aerial Photograph 5) and about 1 mile upstream of the upstream end of this study's Channel Problem Area No.3. Bittinger and Stringham (1963) did not provide aerial photographs of this area in their report. TranSect No. 18 measured 132 feet in length and although they took no vegetation samples, the transect area was characterized as Tree and Shrub Growth (Vegetative) Type V - trees and light brush (Bittinger and Stringham 1963:4-7, Table 1; 26, Appendix ill; 31, Appendix IV). Bittinger and *ringham's (1963:15, Table 7) study between La Junta and Las Animas found that Vegetative Type V had decreased by about one- third, from 1340 acres to 841 acres, between the years of 1936 and 1957 while Vegetative Type ill - dense brush and trees had a rather alarming increase in their valley samples from 14 acres to 1280 acres for the same period (Bittinger and Stringham 1963:6, Table 1; 15, Table 7). Their analysis provided "An approximation of the degree of encroachment of saltcedar..." in a "percentage of the total phreatophyte area..." and that for the area between Las Animas and John Martin Reservoir, salt cedar density was 58.4 percerit of the total vegetative cover (Bittinger and Stringham 1963: 19). Their conclusions indicated that salt cedar was the predominate shrub and that the I'increase in density... [was] primarily due to encroachment of saltcedar into areas fonnerly occupied by only cottonwood growth" (Bittinger and Stringham 1963:21). This trend in increasing salt cedar encroachment and density appears to be continuing in Channel Problem Area No.3. In this study's Channel Problem Area No.3 (Figure 2), visual comparisons were made between the 1965 aerial photograph found in Lindauer and Ward (1968:39, Appendix XI), Corps 1980 ortho-photography related to the John Martin Reservoir Project area, and the 1998 aerial photographs (Aerial Photograph 6) provided by the Colorado Water Conservation Board.. On November 3, 2000, the Corps also conducted a field visit to Channel Problem Area No.3. Aerial. photograph comparisons found that vegetative composition in the area was somewhat similar to but is visually much denser than that previously documented. Observation during the field visit 48 I I I I I I I I I I I I I I I I I I I