story by Dennis Hollier
photos by Chris McDonough
The great wiliwili tree in my front yard is blighted. Its crown bristles with dried twigs. Leaves still grow on the lower branches, but in twisted, stunted bunches. They’re gnarled and pocked with galls. The old tree is dying — another victim in a statewide epidemic of parasitic Erythrina gall wasps.
These invasive wasps were first noted in Hawai‘i less than two years ago. Now, throughout the Islands, almost every type of tree in the Erythrina genus is infested, including both native wiliwili and ornamental imports such as the Indian Coral Tree. On the street behind my house, a windbreak of tall wiliwili stands leafless in the sun. These were once venerable trees. Now, to paraphrase Samuel Beckett, they’re more than venerable; they’re dead.
Despite the best efforts of the state’s botanists, there’s still no treatment for the gall wasps. No known pests for bio-control. No poisons to apply. No mutations to muddle the genome of these destructive pests. Fearing the worst—that the blight may only end with the extinction of the wiliwili in Hawai‘i—scientists throughout the state are methodically stocking up on seeds. In the back of Manoa Valley, the botanists at Lyon Arboretum’s Rare Hawaiian Plants Program have ninety pounds of wiliwili seeds on ice. For after the apocalypse.
Of course, the crisis of the wiliwili, although sudden and dramatic, is only the latest episode in the long story of loss and extinction here in Hawai‘i. There are about 1,000 native plant species in Hawai‘i, ninety percent of which exist nowhere else in the world. Hundreds of these species are endangered. Hawai‘i accounts for about a quarter of the federally listed endangered plant species in the country, while countless other unlisted species also teeter on the brink of extinction.
Over the last few years, a network of organizations and conservation professionals has emerged, seeking to preserve these fragile plants. The very public efforts to save the wiliwili simply highlight the largely anonymous work being done to protect Hawai‘i’s other rare and endangered plants. Scientists in white coats toil at their microscopes. Administrators scramble for funding. And high on the windy, perilous ridges of the Ko‘olau Mountains, intrepid field biologists nurture the last dwindling communities of these rare Hawaiian plants. But the nexus of all this quiet work can be found in two unobtrusive laboratories at Lyon Arboretum.