Much of the US experiences periodic drought from time to time. Even though rainfall is generally abundant in Florida, its occurrence is seasonal with 70% of the annual rainfall amount occurring from May to October. Couple this with increased population growth and greater demand for potable water resources, landscapes and other turfed sites typically lose out when outdoor water use is curtailed. Residential water use comprises 61% of the public supply category and is the largest single portion (43%) of groundwater withdrawal in Florida. The use of water for landscape and turfgrass sustenance is a hot topic and many parts of Florida experience restrictions on outside water uses. On top of water restrictions, ordinances which restrict turfgrass use (species selection and square footage limits) are being drafted. Many of these restrictions are only based on casual information, not necessarily science. Grasses undergo many changes in response to drought and some of these responses are not easily noticed. However, they have a profound effect on the plant’s ability to withstand drought. Some of these changes can be very difficult to quantify in the laboratory. Other changes are readily observed and easily quantified. With this in mind, we are addressing drought tolerance of turfgrass from several angles.
Linear Gradient Irrigation System
One way to study the effects of drought on turfgrass is by using a Linear Gradient Irrigation System (LGIS). At the onset of construction, 12” of topsoil was removed and stockpiled using heavy equipment. The subgrade was shaped and laser-leveled to provide a 5″ drop from the outside edges inward to ensure that all surface water flows to the center. After the subgrade was established, the topsoil was replaced, and the final grade was established using laser-guided implements.
Water Quality Plant Genetics and Genomics to Improve Drought and Salinity Tolerance in Turfgrass Species for the Southern United States