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In the “insect apocalypse,” your garden could be a lifeline for insects.

By Carol Stocker, The Boston Globe

November 6, 2024 | 10:19 a.m.

It’s quite a paradigm shift to ask homeowners to stop killing insects to encourage them, but entomologist Douglas W. Tallamy wants homeowners to do just that by replacing half of their lawns with native trees.

“When I tell people they can do something on their own property to protect the environment and fight global warming, it gives them a feeling of empowerment. They love it,” said Tallamy, who received the George Robert White Medal of Honor from Massachusetts Horticultural Society at Elm Bank in Wellesley on October 30.

Which trees to plant?

“Make them oak trees, because they have the most wildlife,” Tallamy said in an interview with the Globe. “Lawn is the worst plant for sequestering carbon. The roots are shallow and you cut off half the leaves each week. Lawns contribute to climate change, but trees are great.

Tallamy’s award-winning books “Bringing Nature Home: How You Can Sustain Wildlife With Native Plants” (2007) and “Nature’s Best Hope: A New Approach to Conservation That Starts in Your Yard” (2020) have been highly influential among gardeners . The message is that forests are more effective in combating global warming than lawns, wildflower meadows and gardens. They’re also much easier to maintain, especially if you mulch with leaf mold or ground cover plants to create a no-walk zone underneath. Tallamy said to keep the lawn in the front yard to keep the neighborhood clean and in areas where you walk, because lawns provide protection against ticks without spraying. (Ticks hate lawns.)

Oak trees are home to several hundred different caterpillars. Their soft bodies serve as food for baby birds (which cannot digest seeds from bird feeders). Tallamy said a pair of Carolina chickadees needs 6,000 to 9,000 insects to raise a brood of chicks, providing a round-trip delivery service every six minutes from 6 a.m. to 8 p.m., seven days a week If you spray your garden with insecticides, their babies could starve.

Surprisingly, the insect population is in alarming decline, in part because insecticides have worked too well. Some call it the “insect apocalypse,” but all higher animals, including birds and humans, cannot survive without insects, Tallamy said. “They are the foundation of the food chain.”

Because they evolved here, native trees harbor 10 to 100 times more insects than “pest-free” ornamental plants in other parts of the world. In addition to planting red and white oaks, Tallamy recommended replacing Japanese hydrangeas and your lawn with native sugar maples, red maples, black cherry trees, willows, shadbushAmerican sycamore, river birch, box elder, American basswood, American dogwood, hackberryAmerican holly and Princeton elm. For more information, visit the Tallamy website at homegrownnationalpark.org.

No room to plant a forest? Perhaps the easiest way to combat the decline of birds and insects is to simply turn off your outdoor lights, Tallamy added. “Install motion-activated security lights to reduce disturbance from nocturnal insects and animals like owls.”

Other honorees at the 121st Medal of Honor Dinner were David Barnett, CEO Emeritus of Mount Auburn Cemetery; landscape architects Patrick Chassé, Thomas R. Ryan‚ and Matthew J. Cunningham; Murphy Westwood of Chicago Morton Arboretum; and Barbara E. Millen, National Committee Chair Center for Plant Conservation.

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