Versatile Native Grasses and a Turf-Alternative Groundcover for the Arid Southwest United States

Abstract

Water use limitations offers new opportunities for utilization of low-input native grasses and groundcovers for the landscapes of southwest USA. Two field studies were conducted with eleven plant species for two years in Scottsdale and Sun City West, AZ to evaluate rate of emergence, ground surface coverage, plant height, and overall plant quality. In the laboratory, Eragrostis tef at 86% and Eragrostis intermedia at 85% were showing higher percentage of germination compared to other species. Within eight weeks, ten species exhibited an average of 81% emergence at Scottsdale while nine species showed only 58% emergence at Sun City West. Sporobolus cryptandrus grew to greater than 76 cm (30 in) in height while kurapia (Lippia nodiflora) grew to about 5 cm (2 in). The performances of the groundcover kurapia and the native grasses tested demonstrated excellent potential in the low desert southwest U.S., with low rates of water use, applying fertilizer only at planting, and less frequent mowing requirements. Lippia nodiflora, Sporobolus airoides, Bouteloua gracilis, Eragrostis intermedia, and Muhlenbergia asperifolia remained green throughout the year when mowed twice a year. Lippia nodiflora, Hilaria rigida, and Bouteloua gracilis exhibited the highest ground surface coverage and uniformity in growth. Index words: groundcover, landscape, low input, native grasses, plant species. Species used in this study: Blue grama, Bouteloua gracilis (Kunth) Lag. ex Griffiths; bufflograss, Buchloe dactyloides (Nutt.) Engelm.; plains lovegrass, Eragrostis intermedia A.S. Hitchc.; teff, Eragrostis tef (Zucc) Trotter; big galleta, Hilaria rigida (Thurb); Kurapia, Lippia nodiflora (L.) Greene; alkali muhly, Muhlenbergia asperifolia (Nees & Meyen ex Trin.) Parodi; alkali sacaton, Sporobolus airoides (Torr.) Torr.; spike dropseed, Sporobolus contractus A.S. Hitchc.; sand dropseed, Sporobolus cryptandrus (Torr.) A. Gray; and desert zinnia, Zinnia acerosa (DC.) A. Gray.