Did you know that lawns and turf grass cover over 40 million acres in the United States? This makes it the largest single “irrigated crop” by surface area in the U.S. For decades, the ideal American landscape was a large expanse of closely mowed lawn. While lawns provide space for recreation and aesthetics, they contribute relatively little to local biodiversity. Increasingly, homeowners and land managers alike are discovering that even modest reductions in lawn areas can create valuable habitat for pollinators, birds, and beneficial insects. By replacing portions of turf with diverse native plantings, we can transform properties into functioning ecosystems that support wildlife while often reducing long-term maintenance needs.
I recently completed reading a book by entomologist Dr. Douglas Tallamy called Bringing Nature Home. Tallamy argues that native plants are the foundation of healthy food webs because many native insects have evolved alongside them and depend upon them for survival. When native plants disappear from the landscape, insect populations decline, reducing food resources for birds and other wildlife. Tallamy describes an "unbreakable link" between native plants and native wildlife, emphasizing that gardeners can make significant contributions to biodiversity simply by choosing native species.
Tallamy is perhaps best known for his observation that lawns are among the least productive landscape features from an ecological standpoint. Through his Homegrown National Park initiative, he has popularized the idea that if half of America's lawns were converted to native plantings, the result would be the equivalent of a 20-million-acre national park supporting biodiversity across the continent.
Locally, homeowners have many opportunities to put these concepts into practice. Replacing lawn with native trees such as oaks, native shrubs like arrowwood viburnum, and flowering perennials such as purple coneflower, wild bergamot, and goldenrod can dramatically increase habitat value. Research highlighted by Tallamy consistently shows that native plants support far more insect species than many commonly used exotic ornamentals, providing the food needed by birds and other animals throughout the growing season.
An often-overlooked benefit of plant diversity is natural pest management. A landscape containing a variety of flowering plants attracts predatory and parasitic insects that help suppress pest populations. These beneficial insects include lady beetles, lacewings, hover flies, assassin bugs, predatory wasps, and numerous parasitoid species. Diverse plantings provide nectar, pollen, shelter, and alternative prey that sustain these natural enemies even when pest populations are low.
This principle has been frequently discussed by Ohio State University Extension educators and specialists through the Buckeye Yard and Garden Line (BYGL). BYGL contributors often emphasize the importance of preserving "bio-allies," including predators and parasitoids that naturally regulate pest populations. Joe Boggs wrote an excellent commentary on this very topic earlier this year (bygl.osu.edu/node/2635). In his discussions of bagworm management, Boggs also notes that biological controls such as Bacillus thuringiensis var. kurstaki (Btk) are valuable partly because they do not harm beneficial insects that provide natural control of bagworm populations.
Bagworms offer an excellent example of why biodiversity matters. These caterpillars can severely damage arborvitae, junipers, spruce, and many deciduous trees when populations become high. However, landscapes dominated by a few plant species often experience greater pest problems because they provide abundant food for pests while offering limited support for natural enemies. By contrast, landscapes with a mixture of native trees, shrubs, grasses, and flowering plants create habitat for parasitoid wasps and other beneficial insects that help keep pest populations in check. Boggs reinforces the fact that preserving these natural enemies is a critical part of integrated pest management.
Joe shared these key pieces of scientific backing for these principles: “A scientific paper published in 1976 showed that the parasitoid wasp, Itoplectis conquisitor (family Ichneumonidae) accounted for almost 76% of the parasitism observed on common bagworms in the study. This parasitoid wasp commonly visits flowers to sip nectar. It's a pollinator and a parasitoid.” Additionally, “A study published in 2005 showed parasitism rates of I. conquisitor exceeded 70% in bagworm-infested plants that were next to a central flower bed, but less than 40% in infested plants with flower beds further away. In other words, an effective insecticide-free long-term bagworm management strategy is to supply parasitoid wasps with nectar by planting flowering plants.”
The transition from lawn to wildlife habitat does not have to happen all at once. Homeowners can begin by converting a small corner of the yard, expanding garden beds, planting a native tree, or establishing a pollinator border along a property edge. Even modest changes can increase insect diversity, support birds during nesting season, and improve ecological resilience.
As Tallamy shares, gardeners have become important players in conservation. The cumulative impact of millions of individual decisions can help rebuild the ecological connections that sustain wildlife. By replacing portions of lawn with diverse native plantings, homeowners are not simply creating attractive gardens. They are helping restore the food webs, beneficial insects, and natural processes that make healthy ecosystems possible.
Frank Becker is the Agriculture and Natural Resources Extension Educator with Ohio State University Extension – Wayne County, and a Certified Crop Adviser, and may be reached at 330-264-8722 or becker.587@osu.edu
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This article was previously published in The Daily Record.