Working with his bare hands, acclaimed poet William S. Merwin took decades to turn 19 acres of once-barren East Maui pineapple land into one of the largest private collections of palm trees in the world.

The poet, known for living an environmentally conscious lifestyle, has now permanently protected his palm forest with a perpetual conservation easement to the Hawaiian Islands Land Trust.

Merwin, 87, the 2010 U.S. poet laureate, and his wife, Paula, continue to live in their house in the palm forest, and the trust will make sure under the conservation easement established Oct. 10 that the palms remain protected even if portions of the land are sold later.

“From the start, 30-some years ago, Paula and I have hoped to be able to save this bit of the wrecked land and valley of Peahi Stream,” Merwin remarked upon signing the permanent conservation documents. “To see a fully organized and legally expressed conservation easement take form is a reassurance and a great joy to the both of us.”

The Merwin Conservancy, a nonprofit organization, would remain in charge of managing, maintaining and expanding the Merwin Palm Collection.

“We are deeply honored to have worked with W.S. Merwin and his wife, Paula, so they could achieve a life dream: the perpetual protection of their beloved palm forest,” said Ted Clement, the Hawaiian Islands Land Trust’s executive director.

Clement said Merwin’s writings have inspired him over the years in his conservation career.

“So it was especially meaningful helping the Merwins save their land,” he said.

Nearly 3,000 palm trees representing 400 species have become what the National Tropical Botanical Gardens call “a living treasure house of palm DNA.”

Each palm has been tagged, categorized and placed on a map using global positioning and Google Earth.

Merwin built his house in Peahi in the mid-1970s, relying on solar energy for power.

He writes in the mornings and tends to his palms in the afternoons. His writings are quite often meditations on nature and the conduct of humankind.

Merwin has more than 30 published works of poetry, prose and translations, including “Migrations” (National Book Award, 2005), “Shadow of Sirius” (Pulitzer Prize, 2009) and his most recent book, “Moon Before Morning” (2014).