Douglas Tallamy, whose influential 2007 book “Bringing Nature Home” made many gardeners aware that growing native plants is essential to preserving native wildlife, has launched a new project.

“We are in the midst of an insect apocalypse,” Tallamy told the more than 300 people attending a locally sponsored webinar earlier this month. “We are in the midst of the Sixth Great Extinction, and it is caused by us.”

The program was sponsored by the National Garden Club, which includes the Garden Club Federation of Maine and the Cape Elizabeth Garden Club, of which I am a member.

Humans are causing this extinction, he said, as our population grows (there are nearly 8 billion of us today, about double the number from just 50 years ago), and as people raze natural landscapes for houses with sterile gardens, cities, highways, airports and monoculture fields of crops.

To prevent, or at least slow, that extinction, Tallamy proposes that ordinary people around the country create what he calls the Homegrown National Park. Existing national and state parks in the United States aren’t enough, he argues. They are too few and too small to preserve enough wild lands, plants and animals needed to save the Earth. In total, such parks make up only about 12 percent of the country, and most were chosen for their beauty rather than their ecological significance, he said.

Many wild plants and animals are extinct, virtually extinct or endangered, among them the American chestnut, once common from Maine to Georgia; and the rusty patch bumblebee, which is virtually extinct today. There are no longer enough beavers, whose dams used to control runoff from rainfall, to provide that benefit. When wildlife disappears from local ecosystems, so do their services – such as flood control, pest control, clean water and carbon storage – all of which trickle up to benefit mankind.

Although Tallamy has written several groundbreaking books on restoring the Earth’s biodiversity, he credited the science behind the Homegrown National Park to Harvard biologist Edward O. Wilson‘s “Half Earth: Our Planet’s Fight for Life.” “E.O. (Wilson) says we have to support life on half of the Earth if we are going to save life on Earth,” Tallamy said. “We have to give up the idea that humans and nature can’t co-exist.”

With this project, Tallamy’s goal is to restore 30 percent of the globe to a natural state by 2030 and 50 percent by 2050.

Step one is for homeowners to make their yards more nature-friendly and then to register them at homegrownnationalpark.org. Tallamy would like to see 20 million acres of backyards in the United States supporting wildlife. But even if the Homegrown Park reaches that goal, it amounts to less than 2 percent of what is needed, he said.

The website includes maps – Tallamy compared them to the county-by-county COVID maps – that show where homeowners are adding their properties to the Homegrown National Park, as well as advice on how to start and then expand natural gardens. To demonstrate what not to do, Tallamy showed several photos of sterile home landscapes with lots of lawn and a few nonnative shrubs up next to the house.

If ordinary homeowners planted native plants, like these in the UMaine Cooperative Extension demonstration garden in Falmouth, it could help slow the extinction of wildlife, Douglas Tallamy says. Kate Irish Collins/The Forecaster

His advice for the garden is nothing new, Tallamy noted. It combines efforts by groups like the Audubon Society and National Wildlife Federation as well as the Maine-based Wild Seed Project. Shrinking lawns is just one piece of the project. Additionally, when homeowners buy plants they should consider not merely their attractiveness but their value to nature: Do they provide food for animals, insects and pollinators? Do they store carbon, prevent runoff and improve the soil?

For cropland, Tallamy recommended the return of hedgerows, with native plant populations separating the fields and supporting wildlife. At the same time, commercial forests must be maintained to remove invasive plants, which tend to thrive there because deer and other wildlife don’t eat them.

I disagreed with one thing Tallamy said. He claims that most people like gardens, but they don’t like to garden. My experience with garden clubs and readers of this column convince me otherwise – but maybe I just don’t know that many non-gardeners. But I agree with him that landscaping companies, not just individual gardeners, need to start creating the type of yards that will add to the Homegrown National Park.

We love it when skipping a chore turns out to be good for the environment. Do not rake up all the leaves in the fall (and certainly don’t use a leaf blower!), Douglas Tallamy says, as the leaves shelter the eggs of many beneficial insects. Andy Molloy/Kennebec Journal

Tallamy sprinkled his talk with gardening advice: Avoid seeds coated with neonicotinoid pesticides because they don’t prevent pests and they do poison groundwater. Don’t rake all the leaves in the fall, because beneficial insects lay eggs in the leaves that hatch in the spring. Don’t leave outdoor lights on at night, or if you must, use LED bulbs that give a yellow light, which are less confusing to beneficial insects.

My main takeaway from Tallamy’s talk is that every little thing people do in their gardens has an impact on the health of the planet. While the individual gardener’s effect may be small, all of us together can make a difference.

Tom Atwell is a freelance writer gardening in Cape Elizabeth. He can be contacted at: tomatwell@me.com.