Species Adapted for Planting Arizona Pinyon-Juniper Woodland

Abstract

Species adaptation trials were observed over periods varying from 21 to 28 years at ten Arizona pinyon-juniper sites. Fifty-nine species and varieties developing fair to excellent stands and persisting five or more years were considered adapted to one or more of the sites. Fifty-four of these were still present at the last rating. Thirty have reproduced themselves and are spreading naturally. Most widely adapted species are Agropyron desertorum, A. intermedium, A. smithii, A. trichophorum, Atriplex canescens, Bothriochloa ischaemum, Bouteloua curtipendula, Muhlenbergia wrightii, and Tridens elongatus. Moisture variation caused some cool season grasses to fluctuate more widely in growth and stand than the other adapted species, especially shrubs. Warm-season growers were generally sensitive to low temperatures and cool-season growers to high temperatures. Complete protection from livestock appeared to have detrimental effects on some species. Sites are described and classified to help identify planting potential and facilitate wide application of results. Guidelines are suggested for shortening the time period needed to evaluate species adaption.