Turfgrass covers 40 million acres in the U.S., or nearly 2% of the land, and is the U.S.’s number one irrigated crop (yes, the USDA considers it a “crop.”) Turfgrass management is an important component in the multi-billion-dollar industries of lawn maintenance, park facilities, sod/seed farms, sports field maintenance, and so forth. The combined revenue for all landscaping services alone in the U.S. is over $100 billion.
Yet the maintenance of turf requires nearly 20 trillion gallons of water annually, as well as fertilizers, and other inputs that consume natural resources and impact the environment. As a result, some are calling for the elimination or reduction of turfgrass because they believe the costs outweigh the benefits. In a similar fashion, some states and local communities are banning fertilizer and/or pesticide use.
But there are many ecosystem benefits provided by turfgrass, such as capturing carbon, producing oxygen, reducing chemical leaching and runoff, minimizing soil erosion, improving soil health, and lowering temperatures and noise pollution. And according to surveys taken over several years, the “kept” and formal appearance of turfgrass is valued by people, especially Americans, as an important aspect of their living spaces. International studies have found lawns are culturally significant and common in North America, as well as Europe and Australia. While some argue we need a shift away from this mentality, the fact remains that people value beautiful landscapes that include turfgrass. Despite the costs, societies across the globe value turfgrass and its socially unifying abilities (sports, recreation, etc.) as part of their communities.
While non-vegetated surfaces do not generate the same economic, environmental, and societal benefits that natural grass and other landscape plants provide, we can’t ignore the need to be better stewards. So how do we manage turfgrass for maximum benefit while still providing for sustainability? Here are a few basic guidelines to enhance community aesthetics and ecosystems with lawns, while keeping conservation in mind.
1. Smart Irrigation. Water is increasingly scarce as populations increase, global temperatures rise, and droughts are more frequent. As a result, water management is a growing issue on the international stage. While water use for turfgrass is significant, part of the problem could be solved through better management. Recent surveys show that the average homeowner grossly overwaters their lawns. Correcting this could save trillions of gallons of water annually.
Instead, irrigate deeply and infrequently. Use “smart irrigation” controllers to avoiding runoff and leaching losses below the root zone. Try fostering deeper rooting with intentionally moisture stressing the grass twice in spring and properly fertilizing, especially avoiding excess nitrogen.
2. Frugal Fertilization. Most of us understand that fertilization is necessary for quality lawns. Yet like irrigation, we tend to over-apply fertilizers. Fertilizer misusage and nutrient pollution have gotten to the point that several states and cities have banned certain fertilizers—primarily due to surface water quality issues (eutrophication). In a case study of fertilizer run-off in 2013, researchers found that roughly 25% of the tested residential lawns were using more nitrogen fertilizer than was legally permitted. And in most of these cases, nitrogen application was about 54% higher than recommendations proposed by the University of Michigan Extension Services that same year.
Apply proper rates of nitrogen (and sulfur) to spread out its release through the entire growing season, including some in the fall prior to winter. Apply 0.5-0.7 lb N per 1000 ft2 for every month of active growth with at least 50% as a slow/control release. Two to three applications of a proven slow/control release fertilizer will generally enable season long availability. Apply phosphorus, potassium, and micronutrients based on soil tests done every three to five years. Plant tissue and water testing is also beneficial in some cases.
3. Smart Species Selection. While turfgrass provides many benefits, it should be in balance with other plant types (trees, shrubs, flowers, etc.). Some landscapes may benefit from a reduction of turfgrass square footage. Allow for biodiversity with a mixture of grasses, trees, shrubs, etc. Select plants based on the purpose of the area and choose plants with drought tolerance and high water efficiency. Where practical, use low-maintenance, water-wise plant types in low-use areas.
4. Proactive Pest Control. There’s no denying the importance of chemicals in turf management, but practices need to be as thorough and careful as fertilizer management. There is no “one-size fits all” solution, and any lack of care can lead to many negative ecological impacts. Applicators must adhere to labeled directions, as well as develop other proactive habits including, but not limited to, varying treatments to avoid resistance build-up and integrating cultural and mechanical practices to develop a program that considers pest lifecycles and potential negative externalities.
What About Artificial?
But what about using artificial turf in some situations, such as sports fields? Despite artificial grass being advertised as low maintenance, installation costs are high and studies show the average cost per year for maintaining artificial turf (brushing, cleaning, etc.) is not significantly different than that of natural turfgrass. While artificial turf does reduce water, pesticide, and fertilizer use, it isn’t without environmental costs. Water must be used to clean and cool it. Further, the plastics, rubber, etc. used to create artificial turf are often derived from non-renewable resources and represent a significant environmental concern regarding resource consumption and disposal. Finally, artificial turf also comes with an extreme decrease in the environmental benefits of having natural turfgrass in the landscape.
There is no denying turfgrass is important environmentally, socially, and economically. Turfgrass is iconic in the U.S., but it also serves vital roles. It deserves proper management, not elimination.
Dr. Hopkins is a professor in Plant & Wildlife Sciences at Brigham Young University. He has been a Certified Professional Soil Scientist with the Soil Science Society of America since 1992.
Maughan holds a BS in Landscape Management from Brigham Young University, where his studies emphasized turfgrass and soil management in the urban environment. He is currently a graduate student at Utah State University pursuing an MS in Plant Science. His research focuses on control methods of invasive annual grasses in the Wasatch Mountain Range and surrounding areas.
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