The Nature Conservancy in Hawaii

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By Naomi Sodetani

Every summer on Maui, when green seas of kāhili ginger bloom in full gold, blood-red regalia, many hikers often gasp, “Oh, that’s so beautiful!”

"But it’s a deadly beauty,” says Conservancy Invasive Plant Specialist Pat Bily.

Indeed, the exotic South Asian ginger is one of the state’s most noxious alien weeds, its spread hastened by birds that feast on its bright scarlet berries and drop its seeds many miles away. The ginger displaces native mosses, ferns, and other shrubs that form the understory of the Hawaiian forest, while its sprawling, dense roots prevent rainfall from percolating into the water table — thus diminishing the forest’s critical role and function as a watershed.

“Most people don’t understand the problem,” Bily concedes. “‘Why does it matter if it’s native or not?’ People think if it’s green, it’s good.”

A Conservation Hero

Bily is a self-confessed “weed warrior” — and one of Maui’s best. The lanky, bearded Kula resident has led the Conservancy’s weed-control efforts there for almost two decades, foraying almost daily into the island’s forests and outlying areas to vigilantly monitor the balance of native and non-native growth.

In 1991, he organized a project to stomp out Maui’s worst weed threats, beginning with the highly invasive Miconia calvescens. And in 1999 he helped establish the Maui Invasive Species Committee (MISC). Following its multiagency model, other committees have since formed on other islands.

Pat Bily with hapu'u fern tree

Bily has also planted seeds of awareness. Since 1990, he has led monthly volunteer trips to remove weeds and build and repair fences in the Conservancy’s Maui preserves. These work trips have inspired a growing cadre of community conservationists of all ages and all walks of life, including local students, canoe club members, and hunters.

“Every one has tremendous respect for Pat’s dedication, commitment, and hard work,” says Mark White, Director of Maui Programs for the Conservancy. “He is a true conservation hero.”

Mission Possible

Bily strategically pursues his mission. "There's no way we could get enough volunteers, or bulldozers or chemical herbicides or biocontrol to get rid of fields of ginger that have taken over." Gesturing towards a sprawling patch thronging the outskirts of Waikamoi Preserve, he says, "We have to just live and let live with places like this. But

The Conservancy's go-to weed guy is passionate and clear about what's at stake.

The cool, misty air of Waikamoi is perfumed by thriving groves of fragrant maile — rare in Hawai‘i nowadays. This 5,230-acre Conservancy preserve, located on the windward slopes of Haleakala, lies at the heart of the East Maui Watershed — a vast, 100,000-acre koa-‘ōhi‘a forest that is the last stronghold for 24 endangered native plant species and 10 species of endangered native birds.

Standing in the presence of great hapu‘u ferns and towering koa and ‘ôhi‘a trees, some hundreds of years old, Bily’s voice is a reverent hush. “This forest ecosystem has existed up here for hundreds of thousands of years; it’s as old as East Maui itself. Makes you feel pretty insignificant to be in this primal place.”

Native Hawaiian mint When Bily arrived in Hawai‘i 30 years ago, he fell in love with the Islands’ amazing diversity. The admitted plant nerd supported himself farming, raising protea, and ran a landscaping business. Ironically, he notes, “some of the things I’m now trying to remove, like the Australian tree fern, were what I used to grow.”

Volunteering with the Native Plant Society, and helping to cultivate endangered native plants at a Maui arboretum, opened Bily’s eyes. Introduced animals and plants were key factors causing the precipitous decline of the Hawaiian forest. Certain plants and animals are considered “invasive” if they displace native species and permanently alter the composition and functions of the ecosystem.

“Invasive plants and animals pose one of the greatest threats to biodiversity, particularly in island ecosystems,” he says. “If they spread unchecked, they disrupt natural cycles, and globally cause billions of dollars in damage.”

He warns that a newly arrived fungus called ‘ōhi‘a rust” could potentially decimate native ‘ōhi‘a trees, just as the gall wasp, in a few years, has devastated native wiliwili tree populations. A plague of the ‘ōhi‘a disease would be even more cataclysmic, since ‘ōhi‘a and koa are “king canopy trees” that support the whole web of life in native forests.

Bily's 'Ark'

When he is not out battling alien weeds, you can usually find Bily growing native plants and trees. Last year, the Haleakala National Park and National Tropical Botanical Garden gave him cuttings from two plants endemic to East Maui — an endangered native mint and native pepper — both species perilously close to extinction. This mint species inhabits an ultra-tiny 300-yard radius in this specific area of East Maui, existing nowhere else on the planet.

Bily planted the seedlings in a small plot in Waikamoi, and two days after he finished fencing them in, he saw massive pig damage in the area. “If I hadn’t closed it all off when I did, they would have plowed this whole place up and that would’ve been the end of that,” he says.

More recently, several of his former student volunteers — now adults and employed in conservation jobs in Hawai‘i and abroad — returned to help him outplant endangered native geraniums. “Most of the time we’re out killing invasive plants,” Bily says. “So it was a nice break to actually plant something.”

He smiles, warmly recalling the reunion. “It was a pretty joyous day.”

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what’s not been inundated by ginger, we have to prevent it from converting those areas into places like this. Containing the threat — that’s my goal."