Recent vegetation changes along the Colorado River between Glen Canyon Dam and Lake Mead, Arizona

Abstract

document conditions as they were between 1872 and 1963. In general, the older pictures show an absence of riparian plants along the banks of the river. The new photographs of each pair were taken in 1972 through 1976. The most obvious vege tation change revealed by the photograph comparison is the in creased density of many species. Exotic species, such as salteedar and camelthorn, and native riparian plants, such as sandbar willow, arrowweed, desert broom, and cattail, now form a new riparian com munity along much of the channel of the Colorado River between Glen Canyon Dam and the Grand Wash Cliffs.