By Mary Free, Extension Master Gardener
Part 3. Residential Land Use: Lawns
![Mount Vernon and U.S. lawn area](https://i0.wp.com/mgnv.org/wp-content/uploads/2024/05/Mount_Vernon_and_US_Lawn_Area.jpg?resize=800%2C362&ssl=1)
Ever-expanding residential development not only continues to destroy wildlife habitats but affects biodiversity by replacing natural systems with human-made structures surrounded by pollinator– and environment–unfriendly monocultures. Lawns—residential and commercial and golf courses—cover nearly 50,000 square miles in the United States, slightly larger than the land mass of Virginia and Maryland combined.
![](https://i0.wp.com/mgnv.org/wp-content/uploads/2024/06/HillsArchimedeanLawnMower.jpg?resize=709%2C539&ssl=1)
DO YOU KNOW THE HISTORY OF LAWNS?
Early colonists imported grass and clover seeds from Europe to replace the native grasses that could not withstand the grazing of their livestock. The term lawn, referring to a mowed grassy area, was first recorded in 1733 and “George Washington… used it to describe the area in front of Mount Vernon” (Jenkins, 1994). Lawns remained the fashion of wealthy landowners attempting to imitate the landscapes of English country estates until the mid-to-late nineteenth century when the upper and middle classes started fleeing the industrial cities. Suburban developments built to house them adopted landscape designs partly influenced by the pastoral style of newly created urban public parks with their open greenspaces and smattering of trees and shrubs.
The promotion of houses surrounded by well-tended grass lots coincided with U.S. patenting of the first reel lawn mower and lawn sprinkler. Also at this time, golf was gaining popularity and by the turn of the century there were 1000 golf courses in the U.S. (The National Golf Foundation estimates that at the end of 2023 there were nearly 16,000.) Lawn maintenance, however, remained very labor intensive, so it was not until advancements in lawn equipment and chemicals in the mid-1900s that lawns became an affordable landscape feature for most Americans.
Environmental Impact
Despite what we have learned about the negative environmental impact of lawns over the last thirty years or so, the manicured green lawn aesthetic remains a staple feature of residential properties. These mostly non-native monocultures provide no benefit to pollinators. Instead, consider them as an irrigated crop, using up three times more acres than irrigated corn (Linsey 2005) and along with gardens, about 30% of residential water nationwide. Additionally, the U.S. Environmental Protection Agency (EPA) has reported that up to 50% of that water may be wasted due to evaporation, wind, or runoff. Although lawns soak up carbon dioxide from the atmosphere, the carbon cost of maintaining them with gas-powered equipment and synthetic fertilizers may offset this benefit.
DID YOU KNOW?
• In 2020, lawn equipment in the City of Alexandria produced 14,166.9 tons of carbon dioxide equal to that produced by 3119 cars. The equipment also emitted fine inhalable particles (PM2.5), which cause environmental damage, equal to that produced by 122,691 cars.
• In Arlington County, lawn equipment produced 13,535.82 tons of carbon dioxide equal to that produced by 2980 cars. The PM2.5 emitted by the equipment equaled that produced by 109,197 cars.
You can find Emissions from lawn equipment by county, 2020 for your locality (scroll down to the middle of the page).
The EPA has estimated that gas-powered lawn mowers produce 5% of total air pollution in the U.S. and that a gas-powered leaf blower releases more hydrocarbons than a pickup truck. Gas-powered lawn equipment consumes annually an estimated 800 million gallons of gasoline and another 17 million gallons are wasted due to spillage, often by the use of old gas cans. The Utah Department of Environmental Quality warned that old gas cans also can release volatile organic chemicals (VOCs), which can affect human health.
![Assateague Island National Seashore, Maryland algae bloom from nutrient pollution. Courtesy Eric Vance, U.S. EPA](https://i0.wp.com/mgnv.org/wp-content/uploads/2024/05/Assateague_Island_Natl_Seashore_algae-bloom_9324594954_8f3deec24b_o.jpg?resize=800%2C532&ssl=1)
According to Princeton University, the 3 million tons of nitrogen-based fertilizer used by Americans annually release 4–5 tons of carbon dioxide for every ton of nitrogen created in the manufacturing process. Scientists at UC Berkeley found a direct link between the increased use of synthetic fertilizer during the last fifty years and a rise in nitrous oxide, a greenhouse gas, produced by microbes in the soil. Additionally, the runoff of nitrogen can pollute waterbodies, create toxic algae blooms, and ultimately kill fish and other native aquatic life. Nitrogen can also seep into shallow aquifers, contaminating drinking water.
Home-owner lawn maintenance is time-consuming and requires an initial investment in a variety of equipment and tools and the yearly purchase of lawn care products and fuel if needed. Otherwise, it requires the hiring of lawn care professionals. According to USA Today, in 2024, an annual professional services contract averages about $750 for routine maintenance, not including specialty services like seeding, aerating, fertilizing, herbicide treatment, pesticide application, and seasonal cleanup.
Individual property owners have the most flexibility in how they care for their lawn. Those who live in condominiums or in areas with homeowner associations (HOAs) can work with their governing bodies on lawn issues. Effective October 1, 2021, Maryland’s law on Low-Impact Landscaping prevents condo and homeowners’ associations from imposing unreasonable limitations on homeowners’ use of bio-habitat gardens, pollinator gardens, rain gardens, and xeriscape to conserve water, lower maintenance costs, provide pollution prevention, and create habitat for wildlife. The Alexandria and Arlington Stormwater Management Manuals support similar efforts to rethink and replace lawns and impervious surfaces. (See Part 2. Residential Land Use: Impervious Surfaces.)
What You Can Do
Shrink the size of your lawn to save on lawn care and water costs and to help pollinators. A study published last month (May 2024) showing pollinator diversity loses in western and southern North America, also pointed to abundant and diverse pollinator populations in many urban and developed areas (Souther et al., 2024). It recommended promoting pollinator habitat in these areas by replacing lawns with native plants, as well as educating the public to use fewer pesticides and planting more flowering native species on public lands.
- Identify “the portions of your lawn you need for paths, pets, and play, and then dedicate the rest of your yard to native plants” suggests entomologist Doug Tallamy, co-founder of Homegrown National Park™ (Hassler & Jensen).
- Start off devoting just a small section of your lawn to a native plant garden if a larger project sounds overwhelming or intimidating. Expand the garden areas as you become more comfortable with design, planting, and maintenance.
- Try to create a natural and diverse habitat. The more diverse the vegetation in terms of species, shape, size (with horizontal and vertical layers) and seasonal interest, the more diverse the wildlife it will entice. Be sure to include some “keystone plant genera,” such as Solidago (goldenrod) and Symphyotrichum (aster), each of which supports about 100 lepidopteran species.
- Allow non-native white clover (Trifolium repens) to grow naturally in the remaining lawn or seed it with a microclover and no-mow seed mix. Better yet, choose the less trafficked areas and seed it with bee-friendly lawn mixes that use a combination of white clover and low-growing native wildflowers along with low-growing fescues to create low-maintenance, ecologically friendly 3–5” high lawns.
DID YOU KNOW?
A study of turfgrass interspersed with flowering species found that lawns with naturally growing Trifolium repens (white clover) provided “high quality forage for diverse bee communities,” although a majority were European honey (most common) and other non-native bees with a smaller percentage of native bees (Wolfing et al, 2023). When native floral species were added to the lawn, the composition of the bee community changed. While white clover continued to attract some native bee species, 97% of the visitors to the native flowers were native bees.
- Use xeriscape or water-wise gardening to reduce the need for supplemental watering. Xeriscaping is not just for those who live in arid regions of the country. Rather this drought-resistant, low-maintenance landscaping works in any dry-prone, exposed area where routine watering is problematic. (For a list of suitable plants, see MGNV’s Native Plants for Dry Conditions Best Bets Fact Sheet and video.)
Change the way you maintain your lawn.
- Use electric (or manually-operated) lawn equipment—lawnmowers, leaf-blowers, edgers, trimmers, chainsaws, shredders, etc. California now bans the sale of some gas-powered lawn equipment manufactured after December 31, 2023. In the District of Columbia (except on Federal land) no one may sell or use a gas-powered leaf blower as of January 1, 2022, Montgomery County, Maryland prohibits the sale (starting July 1, 2024) and use (starting July 1, 2025) of handheld, backpack, and walk-behind gas-powered leaf blowers and leaf vacuums.
- Mow your lawn less often and in the evening when ozone is less likely to form if you are unable to replace your gas-powered lawn mower.
- Buy new EPA-approved gas cans with automatic shut-off and closing features.
- Use the grass that grows best in your area and mow the lawn with a sharp blade at the highest height for your grass type—taller grass has healthier roots, retains moisture better, and discourages weed growth.
- Leave grass clippings—spread evenly—to decompose and naturally add nitrogen and potassium to the soil.
- Use organic fertilizer.
- Ask lawn service companies about the equipment and products they use and practices they employ so that the service you hire will care for your lawn in an environmentally-friendly manner.
- Irrigate your lawn early in the morning and deeply, so that it receives ½ –1” of water per week including rainfall (monitor rainfall with a rain gauge). How much water your lawn needs per week depends on the type of grass. How many times per week you have to irrigate depends on the soil (clayey soil once or twice a week; sandy soil two or three times a week).
- Alternatively, provide little to no supplemental water for well-established lawns. Under droughty conditions and intense heat, the lawn will yellow and become dormant. It will green up with rain and cooler temperatures.
![Vintage buck saw, weed whip, reel mower, and garden push plow, some dating back to the 1920s.](https://i2.wp.com/mgnv.org/wp-content/uploads/2024/05/Old_buck_saw_weed-whip_reel_mower_push_plow_JF.jpg?ssl=1)
![Gas-powered trimmer and chain saw](https://i0.wp.com/mgnv.org/wp-content/uploads/2024/05/Gas-powered_-trimmer_and_chain_saw_JF.jpg?ssl=1)
![A gas-powered lawn tractor.](https://i1.wp.com/mgnv.org/wp-content/uploads/2024/05/Gas-powered_Lawn_Tractor_JF.jpg?ssl=1)
Note: Click on images to see enlarged photos, captions, and photo attributions. On a mobile phone, click on the information symbol (circle with a letter ℹ︎ symbol).
Next up: Part 4. Residential Land Use: Invasive Species
MGNV Resources
Uncertain on how to replace your lawn or choose turf grass native alternatives, then the following MGNV resources may help:
- Case Studies in Lawn Replacement and Turf Grass Alternatives videos
- The Lure of the Lawn
- Rethinking Your Lawn
- Take this lawn and . . . shrink it
- Tried and True Native Grass and Sedge Selections for the Mid-Atlantic fact sheets
References
Banks JM. McConnell R. 2015. National Lawn and Garden Equipment Emissions. 2015 International Emissions Inventory Conference, San Diego, CA.
Dutzik T, Sokolow L, Schatz K, Metzger L. 2023. Lawn Care Goes Electric. Environment America Research & Policy Center.
Fresenburg BS. 2010. Proper Mowing Practices for Your Lawn. Integrated Pest Management, University of Missouri.
Gage EN, Alpert Y. 2024. Average lawn care cost (2024). USA Today.
Hassler G, Jensen G. Native Bee Lawns: The “Better” of Both Worlds. Homegrown National Park. (accessed May 6, 2024).
Keystone Plant Guides. Homegrown National Park™. (accessed May 6, 2024).
Lindsey R.2005. Looking for Lawns. NASA Earth Observatory.
Maryland-2021-HB322: Real Property – Restrictions on Use – Low–Impact Landscaping. [PDF]
Montgomery County Executive Elrich Signs Bill to Phase Out of Gas-Powered Leaf Blowers and Leaf Vacuums. 2023. Montgomery County, MD Government.
Osborne C. 2018. #NoMowDays and Other Ways to Trim Your Grass and Your Emissions. Utah department of Environmental Quality.
Resources and guides for the 2022 D.C. Phase-Out Law. Quiet Clean D.C.
Sanders R. 2012. Fertilizer use responsible for increase in nitrous oxide in atmosphere. Berkeley News. UC Berkeley.
Seymour RM, Wade GL. 2017. Make Every Drop Count: Xeriscape: Seven Steps to a Water-Wise Landscape. Circular 895-1. University of Georgia Extension. [PDF]
Son J. 2020. Lawn Maintenance and Climate Change. Princeton Student Climate Initiative (PSCI). Princeton University.
Souther SK, Sandor ME, Sample M, Gabrielson S, Aslan CE. 2024. Bee and butterfly records indicate diversity losses in western and southern North America, but extensive knowledge gaps remain. PLOS ONE 19(5): e0289742. doi: 10.1371/journal.pone.0289742
WaterSense. 2013. U.S. Environmental Protection Agency. [PDF] (accessed May 13, 2024).
Wolfin J, Watkins E, Lane I, Portman ZM, Spivak M. 2023. Floral enhancement of turfgrass lawns benefits wild bees and honey bees (Apis mellifera). Urban Ecosystems. 26:361–375. doi: 10.1007/s11252-023-01339-7