By Kai Umeda
There is increasing interest by golf course superintendents and residential/commercial landscapers to consider native grasses and/or new multi-use groundcovers that require less water and management inputs when replacing turfgrass. Golf courses are reducing turf in non-play areas and residential and commercial landscapes are being designed to optimize water use by xeriscaping and incorporating desert-adapted, low water use plants. There is also a need for salt tolerant grasses and ornamental plants because of detrimental growing conditions in high salinity soils and with poor quality water.
When turfgrasses are removed to conserve water and reduce maintenance inputs, there are expectations for the aesthetic qualities of the site to be maintained or improved. An option to enhance landscapes and conserve water is to install low-input grass species or groundcover plant materials that require less mowing, fertilization, and irrigation.
There are native grass species and groundcovers that are drought, heat, and salt tolerant; not as susceptible to diseases and insects; and have relatively low fertility and infrequent mowing requirements. Grass species are alkali muhly (Muhlenbergia asperifolia), alkali sacaton (Sporobolus airoides), blue grama (Bouteloua gracilis), buffalograss (Buchloe dactyloides), big galleta (Hilaria rigida), plains lovegrass (Eragrostis intermedia), spike dropseed (Sporobolus contractus), and sand dropseed (Sporabolus cryptandrus). An introduced warm-season annual forage grass, Teff grass (Eragrostis tef) is gaining interest for pastures and as a hay crop. Groundcovers include a forb, desert zinnia (Zinnia acerosa) and an imported introduction from Japan, Kurapia (Lippia nodiflora).
We’ve received support to assess the low-input adaptation of these species across varying environments in the low desert to determine their performance for germination, emergence, and stand establishment and to generate locally based research information for their water, nutrition, and management requirements in non-play areas of golf courses. Our ultimate goal is to increase awareness and demonstrate for golf course superintendents and landscapers that options are available to substitute alternative plant materials where turfgrasses are removed.
Our field research at the Camelback Golf Club in Paradise Valley, AZ was initiated in 2015 where Kurapia plugs were planted in the spring and early stage herbicide tolerance experiments were conducted. Preemergence and postemergence herbicides were evaluated and preliminary results were corroborated by similar studies conducted in California at the University of California, Riverside and at Cal Poly, San Luis Obispo. A second fall planting of Kurapia compared its rate of establishment during the cooler season.
During the late spring of 2016, the grasses and groundcovers were planted to evaluate and demonstrate their performance in replicated small plots. Over time, the water use, fertility and management practices will be monitored and the newly developed information will be available for adoption by golf course superintendents and landscapers.
Species included in the nativegrasses and groundcovers experiment at Camelback Golf Club, Paradise Valley, AZ.
Alkali muhly is a native grass that can be used as a soil stabilizer because it is strongly rhizomatous and grows in moist to wet, sandy to clay, and neutral to alkaline soils.
Alkali sacaton is a native warm-season grass that is useful for low input, high saline soil conditions, with tolerance to heat and poor soils, and is used for soil stabilization in tough environments where other grasses fail.
Blue grama is a densely tufted, perennial, warm-season, native short-statured grass distributed throughout the Great Plains and Southwest. It has shown potential for use in low-nitrogen soils and arid environments and is suitable for mixtures of grasses used for erosion control.
Buffalograss is a native species that has excellent heat and drought resistance with low fertility and infrequent mowing requirements that can be established from seed, sod, and plugs.
Big galleta is a native perennial, warm-season grass with strong rhizomes that can be used as a conservation groundcover in heavily trafficked areas.
Plains lovegrass is a native, warm-season perennial bunchgrass used as forage grass for livestock and wildlife.
Spike dropseed is a native, perennial, warm-season bunchgrass, 1.5 to 4 feet tall with a spike-like inflorescence. The potential uses of spike dropseed include erosion control, wildlife food/cover, restoration of disturbed areas, rehabilitation of rangeland, and for increasing plant diversity in arid rangeland communities.
Teff grass is a self-pollinated, warm-season annual forage grass, tolerant to drought, has wide adaptation, and ability to survive in moisture-stressed and water-logged soils. Due to its fast germination (3 – 5 days) and fibrous root system, it is an excellent choice for both wind and water erosion control.
Kurapia, a newly introduced sterile selection of Lippia nodiflora was evaluated in California as a low water use groundcover. Aesthetically, the groundcover can stabilize soils on slopes and reduce erosion especially along streetscapes and right-of-way areas along freeways and medians. The plant has prolific flowering capacities and is attractive to honeybees and other pollinators.
Desert zinnia is a small, shrub-like, native, perennial forb that may be used in restoration of disturbed areas, wildlife and pollinator habitat improvement, and to increase plant diversity.
Kai Umeda is and Area Extension Agent, Turfgrass Science at the University of Arizona Cooperative Extension in Tucson, AZ.