A FLORISTIC STUDY OF TSEGI CANYON, ARIZONA

The purpose of this study is to list the vascular flora present in Tsegi Canyon, Arizona, and to describe any change in flora that may have happened during the past hundred years. Plants were collected during the years 1994-1997. Three hundred and ten species representing seventy three families are reported to occur within the Tsegi drainage. Three percent of these species are endemic to the Colorado Plateau and twelve percent of the species found are non-native. A change in floristic composition is found to have occurred in the last century, correlated with a shift in habitat types in the canyon. The canyon of the late 1800' s had a slowly moving stream and marshes along a continuous alluvium. The present canyon has a faster moving stream that has eroded much of the alluvium to bedrock. One species, Cymopterus beckii is a new report for Arizona and also is listed as a candidate for rare and endangered species status.