Deficit irrigation and traffic impacts bermudagrass fairway performance

By Reagan Hejl and Ben Wherley, Ph.D.

Photo: Reagan Hejl and Ben Wherley, Ph.D.

Golf course water use in Texas has become increasingly regulated in the past decade due to persistent drought conditions, diminishing water supplies and rapidly growing population. Many golf courses have been faced with considerable cutbacks to irrigation allocations, but information is limited regarding critical levels needed for maintaining adequate turf quality, persistence and recovery from divots and traffic.

A field study was conducted over two years in College Station, Texas, to determine the effects of continuous reference evapotranspiration (ET°)- based deficit irrigation levels on quality of Tifway bermudagrass (Cynodon dactylon x C. traansvalensis Burt. Davy) fairway plots. Turf quality evaluations from both seasons demonstrated that in the absence of traffic, irrigation levels of 30% x ET° (supplied 3x/week on a fine sandy loam soil) were sufficient to maintain acceptable turfgrass quality during summer months. Canopy temperatures noticeably increased with deficit irrigation practices, with up to a 30°F temperature increase observed between irrigated and unirrigated plots.

Upon resumption of full irrigation levels in October of both years, deficit and unirrigated plots quickly recovered to ^~90 percent green cover by late November 2012, but these same plots were much slower to recover after the 2013 season, indicating cumulative drought stress effects, especially in unirrigated plots. In both years, traffic delayed fall recovery of turf at all irrigation levels. This research was supported by the GCSAA’s Environmental Institute for Golf and the Lone Star Chapter of Golf Course Superintendents.

Reagan Hejl and Ben Wherley, Ph.D., Texas A&M University, College Station, Texas. Ben Wherley can be contacted at b-wherley@tamu.edu for more information.