Evaluation of species establishment and revegetation practices along roadsides in Tucson, Arizona.

Abstract

This study evaluated the success of recently revegetated roadsides in Tucson, Arizona. The primary objectives of this study were to (1) evaluate a sample of revegetated roadsides by assessing site condition and comparing existing vegetation to the original seed mix; and (2) develop recommendations for appropriate revegetation practices for use in Tucson. Density data were collected at 20 locations using belt transects to derive species information such as origin, vegetative life-form, and invasiveness. Results indicated that the study sites had greater proportions of plant material not specified in the original construction documents than specified plant material. Of the specified species, creosote bush, desert senna, and triangle-leaf bursage had the highest rates of establishment while brittlebush, globemallow, shrubby buckwheat, and fourwing saltbush provided the most vegetative cover. Several non-specified species exhibited successful establishment on many study sites, while some species rarely or never appeared in the study area despite frequent specification.