Lanai Sandalwood

Santalum freycinetianum var. lanaiense

Description

The Santalum freycinetianum var. lanaiense (Lanai sandalwood), known in Hawaiian as 'ilahi, is a small moderately branched tree with a gnarled trunk. Its leaves are shiny dark green above and lighter green below, and vary in shape from round to oblong. The ends of branches bear clusters of bright red flowers, which develop into a berry-like fruit.

The flowering period of the Lanai sandalwood varies from late summer to early fall, with flowering frequent and fruiting occasional. Vegetative reproduction by root suckers has been noted infrequently. Observations of other species of sandalwood indicates that flowering does not usually begin until plants are three years old and viable fruit is produced at about five years. Related species of sandalwood are hemiparasites that require the availability of the roots of other plants to maintain vigor during at least some growth stages, particularly young stages. The specific requirements and preferences regarding these aspects of the life cycle of the Lanai sandalwood are not specifically known. Sandalwoods are valued for their fragrance and beauty and have been used extensively for incense and decorative woodworking.

The growth of sandalwoods is slow. In areas where commercial sale of sandalwood is being explored, 50-100 years are required to grow a tree of "merchantable" size.

Habitat

The Lanai sandalwood occurs in habitat ranging from coastal, dryland, tropical forest to higher elevation woodland. It grows in shallow, well-drained soils that support only a sparse plant cover. The sites it now occupies have been severely degraded by livestock and exotic game animals.

Distribution

The Lanai sandalwood was once widely distributed on the island of Lanai, Hawaii. It has been found nowhere else.

Threats

When the Lanai sandalwood was listed as Endangered in 1986, only 39 trees were known to survive, grouped roughly into two populations. One is near Kanepu'u, and the other near the summit of the island. Almost all trees occur on private land owned by Castle and Cooke, a major agricultural firm.

Extensive trade in Hawaiian sandalwoods from 1790 to 1820 resulted in a decline in the species, but the Lanai sandalwood has not been commercially exploited in this way for some time. Some trees have been cut for sale to hobbyists or woodworkers, but most have been lost to agricultural conversion and land-use practices. Chronic overgrazing by cattle, sheep, and axis deer has severely degraded the dry-land forests of Lanai. Much of the native ground-cover has been removed, increasing erosion of the fragile soils and allowing alien plants to invade and cause severe ecological damage. In addition, large tracts of forest have been cleared for pineapple production. Spike disease, destructive to sandalwoods in India, is suspected to affect sandalwoods on Hawaii and may be a threat to the Lanai sandal-wood.

A more immediate threat to the survival of the Lanai sandalwood is predation of its fruit by introduced rats. Rats feed on the fruit before it ripens, and all but eliminate reproduction in the wild. Only a single sapling of the Lanai sandalwood has recently been observed.

Conservation and Recovery

At the time of its listing under the Endangered Species Act, all critical habitat of the Lanai sandal-wood was on privately owned land, and was vulnerable to development and other threatening activities. In fact, the landowner opposed the listing of the rare plant because it would automatically invoke protection under state law. The state statute is considerably restrictive and would have interfered with the landowner's long-term development plans for the site. However, after the Lanai sandal-wood was listed as endangered, the landowner agreed to take its custodial role seriously and to cooperate with state and federal recovery efforts. In fact, the landowner granted a conservation easement to the Nature Conservancy of Hawaii, with funding assistance by the State of Hawaii Natural Area Partnership Program. The Kanepu'u preserve will be managed by the Nature Conservancy of Hawaii for native forest conservation and preservation. The Waimea Arboretum and Botanical Garden and the botany department of the University of Hawaii are working with the U.S. Fish and Wildlife Service (FWS) to enhance the recovery of the rare sandalwood. The goal of the Recovery Plan is to protect the remaining population of the Lanai sandalwood from the threats of trampling, grazing, and browsing by herbivorous mammals; from fruit predation by rats; from fire; and from harm by development and recreational use of the habitat. To achieve these goals, the FWS recommends acquiring management rights to the habitat; fencing the habitat and removing feral animals; controlling rodents; building a firebreak around the Kanepu'u population and removing other plants that fuel fires; and cultivating new plants for transplantation to the habitat.

Contact

U. S. Fish and Wildlife Service
Regional Office, Division of Endangered Species Eastside Federal Complex
911 N. E. 11th Ave.
Portland, Oregon 97232-4181
Telephone: (503) 231-6121
http://pacific.fws.gov/

References

Carr, G. D. 1981. "Status Report on Santalum freycinetianum var. lanaiense." U.S. Fish and Wildlife Service Contract. Research Corporation of the University of Hawaii.

Spence, G. E., and S. Montgomery. 1976. "Ecology of the Dryland Forest at Kanepuu, Island of Lanai." Hawaii Botanical Society Newsletter 15: 62-80.

U.S. Fish and Wildlife Service. 1986. "Determination of Endangered Status for Santalum freycinetianum var. lanaiense (Lanai Sandalwood or 'iliahi)." Federal Register 51: 3182-3185.

U.S. Fish and Wildlife Service. "Recovery Plan for Lanai Sandalwood." Portland, Oregon.