They Fought the Lawn. And the Lawn Lost.

Dozens of states have passed legislation to promote the health of pollinators, which include bees, wasps, bats and butterflies, while some have curbed the authority of homeowner association edicts during droughts.

But the Maryland law was the first in the country to limit homeowner association control over eco-friendly yards, said Mary Catherine Cochran, former legislative director for Maryland State Delegate Terri L. Hill, a Democrat who co-sponsored the legislation. The measure gained bipartisan support, passed with near unanimity, and became law in October 2021.

“It’s a really small effort in the face of the international work that needs to be done,” said Dr. Hill, a physician. “But it’s nice that individuals in the community are able to feel that they are empowered to make a difference.”

In December 2020, the Crouches and their homeowner association, which had countersued, reached a settlement. The Crouches were able to keep virtually all of their garden intact, but agreed to remove plantings within three feet of their neighbor’s land and six feet of the sidewalk, and replace them with some sort of grass — they chose native Pennsylvania sedge.

Their fight had a ripple effect. Their lawyer, Jeff Kahntroff, has since resolved not to use pesticides, and when part of a tree fell in his yard, he and his wife left it there for critters to use as habitat. Another Maryland couple, Jon Hussey and Emma Qin, were able to point to the law after their homeowner association objected to weeds in their lawn, which they kept mowed but pesticide free. “It’s crazy how ingrained turf grass has become,” Mr. Hussey said. “It doesn’t have to be that way.”

In the end, the Crouches spent $60,000 on lawyers fees, but they say it was worth it. This fall, with the new law backing them up, the Crouches let their dead coneflowers, sunflowers and other perennials stand. Mr. Crouch awoke one frigid morning this November to find six birds on the stalks, feasting on the seeds.

“Maryland was a big deal,” Dr. Tallamy, the ecologist, said. “Now people know if they fight back, they can win.”