Sometimes Baron Horiuchi and his work at Hawaii’s Hakalau Forest National Wildlife Refuge are all that stand between a plant and its disappearance from Earth.

Phyllostegia brevidens was thought to be extinct for more than 100 years, before being discovered on the refuge. Since then, Horiuchi has propagated and replanted more than 1,000 of the native plants, ensuring the species’ survival.

As the U.S. Fish and Wildlife Service’s only horticulturalist, Horiuchi leads a team of volunteers and staff in restoring native and endangered species at Hakalau Forest Refuge. Because of his persistence and ingenuity, more than 6,000 other plants of seven endangered species have been propagated from seeds and cuttings, greenhouse–grown and planted in protected areas.

Horiuchi’s techniques have resulted in the propagation of several endangered Hawaiian lobeliad and mint species. The lobeliad Clermontia pyrularia is down to six individuals in the wild; he has propagated 1,100 in the greenhouse in the past decade and a half. Cyanea shipmanii lobeliad is down to three individuals in the wild; he has propagated 800. Endangered mints Phyllostegia velutina and Phyllostegia racemosa are down to 10 individuals each in the wild; he has propagated hundreds.

“You learn how not to give up on plants,” Horiuchi says. “It’s like creative work.”

For his contributions toward native plant propagation at Hakalau Forest Refuge, the Service awarded him the 2012 Rachel Carson Award for Scientific Excellence. “We are honored that Baron has been recognized with this award,” says Service Pacific Region Director Robyn Thorson.

Since 1987, almost 500,000 native plants, including koa trees, have been planted at the refuge, which is on the windward slope of Mauna Kea, a 13,796–foot dormant volcano on the Big Island of Hawaii. Each year 20,000 plants are grown at the refuge greenhouse.

Horiuchi cultivates plants—and partnerships, too.

Seeds are collected, germinated, propagated and transplanted by volunteers he supervises. The program is so popular with conservation partners that volunteer weekends are booked a year in advance. A greenhouse entrance sign made for Horiuchi by volunteers features the Hawaiian word Laulima.

“Laulima means ‘many hands working together.’ The work I do would not be possible without our volunteers, and all of the other refuge staff,” says Horiuchi. “The volunteers are about the island—it is in their heart. They are passionate about this work, just like the refuge staff. Mahalo to all of them for making Hakalau Forest Refuge what it is today.”

Native Forest Restoration

The refuge was established in 1985 to conserve habitat for some of the most diverse native bird populations in Hawaii. Little was known then about large–scale native forest restoration. So refuge staff began intense adaptive management, conducting carefully designed small experiments as part of broader forest restoration.

At the time, Hakalau Forest Refuge’s 32,733 acres resembled a pasture. Now, as a result of adaptive management techniques used by refuge staff and replanting led by Horiuchi, the slopes of Mauna Kea are returning to native forest habitat, and native bird populations are stable or increasing.

Many of the native bird species, such as ‘apapane, ‘i‘iwi, Hawaii ‘elepaio, and Hawaii ‘amakihi, are seen within replanted areas and returning forest habitat. In addition, the endangered Hawaii creeper and ‘akiapola‘au regularly forage in replanted koa groves.

“If you plant it, they will come,” says Horiuchi. “That’s how I found out I loved the ‘elepaio, when it was the first bird I started seeing come back to the koa trees.”

Forest restoration at the refuge creates a necessary hedge against extinction for many Hawaiian bird species and serves as a hopeful model of how Hawaiian forest may be restored elsewhere.

Horiuchi can’t imagine working anywhere else. “I love these trees, this forest, this island,” he says. “It’s in my heart.”

Megan Nagel is a public affairs officer in the Pacific Region office in Portland.