USDA-Funded Experiment Puts Lawns to the Test Against Sudden Summer Drought

When a lawn browns during a dry spell, most homeowners see a cosmetic problem. A research team at Binghamton University, State University of New York, sees something far more consequential: a window into how one of the most widespread human-managed ecosystems on the continent will cope with a climate that increasingly delivers its water in short, unpredictable bursts. Assistant Professor of Ecosystem Science Amber (Amy) Churchill has received a 298,476-dollar grant from the U.S. Department of Agriculture to expand an ongoing field experiment at the university’s Nuthatch Hollow, pushing the project into new territory by experimentally manipulating how much water the lawn plots receive and tracking the consequences over successive years.

The funding arrives at a moment when the familiar rhythms of lawn care are being quietly upended. Climate change has produced sudden and unexpected shifts in weather patterns, including dry spells that arrive without the warning that seasonal drought planning once assumed. For the turfgrass systems that carpet suburban yards, public parks and golf courses across the United States, these shifts raise a practical question with real resource implications: can a lawn stay green and functional without escalating demands for irrigation, fertilizer and chemical management? Churchill’s project is designed to answer that question at the level of individual plots, species mixtures and years, rather than relying on snapshots taken during a single establishment season.

The experimental platform at the heart of the work is the Pasture and Lawn Enhanced Diversity Global-change Experiment, known by the acronym PLEDGE. The site sits within Nuthatch Hollow, an outdoor laboratory and wildlife sanctuary gifted to Binghamton University by Robert F. Schumann and the Schumann family. Established in the spring of 2024, PLEDGE was conceived with an overarching goal of studying the functional effects of plant diversity on lawns and examining how these grass-dominated systems respond to external factors such as fertilization. The new USDA grant allows the team to maintain the field site as a long-term project, a shift that Churchill argues is essential for understanding lawns on their own ecological terms.

That argument rests on a deceptively simple observation about the life cycle of a lawn. Unlike an agricultural field that is planted and harvested within a single season, a lawn is a persisting ecosystem, installed once and then managed for years or decades afterward. Churchill notes that the project’s long-term framing reflects this reality: how well a lawn is doing years after establishment is as ecologically important as how it performs during the initial construction phase. In other words, the question is not only whether a freshly seeded lawn can be coaxed into existence, but whether the mixtures and management choices made at planting continue to pay ecological dividends when the system is stressed by drought, heat and shifting water availability.

The PLEDGE site consists of 30 enhanced functional diversity lawns, each containing one to three species drawn from a deliberately small and practical palette. Tall fescue, a common grass that most homeowners in the region already have in their yards, anchors the mixtures. White clover, a legume, brings the ability to interact differently with soil nutrients than a conventional grass. Creeping thyme, a short evergreen that grows year-round and flowers almost continuously during the summer months, rounds out the trio. Beyond the field plots, the research team is also working with additional native species in the greenhouse, work that could eventually feed into future recommendations about what homeowners might plant in their own lawns.

The experimental design for the new phase builds directly on this structure. The 30 plots are divided into three groups of 10 based on the species they contain. In the expanded study, each individual lawn will be divided into three sections, with specific groups receiving different amounts of water. This within-lawn split transforms every plot into its own controlled comparison, allowing the researchers to hold soil conditions, history and species composition constant while varying only the water regime. The first year of the new research will focus on quantifying the variation within each lawn, establishing the baseline against which drought effects can be measured. The drought treatments themselves will take place during the second year of the project.

The choice to focus on short-term drought reflects the specific way climate projections bear on the northeastern United States. Churchill notes that in New York, short-term drought, particularly high-intensity pulse droughts with very low water over short intervals that are often combined with high temperatures, are generally predicted to become more common, especially during the summer months. These pulse droughts differ from the slow, season-long water deficits that drought research has traditionally addressed. A lawn can absorb a gradual decline in soil moisture by slowing its growth and deepening its roots; a sudden two-week dry spell stacked on top of a heat wave presents a fundamentally different physiological challenge, and one that falls squarely within the window when lawns are most visibly used and valued.

What the researchers are watching as the drought treatments unfold is not simply survival. Churchill explains that the team is especially interested in understanding how changes in water availability will impact some of the ways people use and rely on lawns, including lawn greenness and plant density, two attributes that directly affect aesthetic value and recreational use. Greenness is the quality homeowners notice first, the visual signal that signals either a thriving yard or one in need of attention. Density, meanwhile, determines whether a lawn can withstand foot traffic, resist weed invasion and recover after stress. By tracking both qualities across the drought gradient, the experiment can translate ecological performance into the practical terms that drive lawn management decisions.

The stakes of that translation are far from trivial. Almost 2 percent of the continental United States is cultivated with turf species, a category that includes lawns, public parks and golf courses. These human-created ecosystems account for an estimated 30 to 60 percent of potable water use for irrigation, meaning that water poured onto grass competes directly with municipal drinking supplies in many regions. Maintaining the traditional lush green appearance also often requires management with fertilizers, herbicides and pesticides, inputs that carry their own environmental costs as they move through soil and waterways. Any finding that allows a lawn to maintain function with less irrigation, or with a species mixture that needs fewer chemical inputs, would therefore scale up to meaningful water and environmental savings across a very large land area.

The project is also designed to look outward, from the field plots to the community that manages millions of additional lawn hectares one backyard at a time. As part of the grant, the researchers will host discussions on managing biodiversity in urban spaces and on how that management can support ecosystem stability under changing environmental conditions. These conversations are explicitly intended to extend beyond fellow researchers: members of the surrounding community are invited to participate and to learn new ways to manage their own backyards. Churchill frames the grant itself as a signal of that orientation, noting that receiving USDA support for the work highlights the commitment that Binghamton University places on community-engaged research. As the drought treatments begin in the experiment’s second year, the green plots at Nuthatch Hollow will serve double duty: a rigorous test of how species mixtures, water stress and time interact in turf systems, and a public demonstration of what a more resilient lawn might actually look like.

Subject of Research: USDA-funded research on the effects of short-term drought on lawn plant diversity and performance

Article Title: New USDA-funded research project to explore the impact of short-term drought on lawns

Article References: New USDA-funded research project to explore the impact of short-term drought on lawns. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: drought, lawns, turfgrass, plant diversity, USDA grant, Binghamton University, PLEDGE experiment, ecosystem science, water availability, urban ecology, climate change, irrigation