Kolea

Myrsine juddii

Description

Myrsine juddii, or kolea, a member of the myrsine family (Myrsinaceae), is a many branched shrub that ranges from 3.5 to 6.6 ft (1 to 2 m) in height. The leathery leaves, 1.6-4.7 in (4-12 cm) long and 0.6-1.3 in (1.5-3.3 cm) wide, are narrowly inverse lance-shaped or more elliptic. The upper leaf surface is hairless, whereas the lower surface is sparsely to moderately covered with short, coarse, stiff, whitish or brownish hairs toward the base and along the midrib. The leaf base is broadly wedge-shaped to heart-shaped, and the margins are smooth and curl under. The flowers are unisexual and the plants are dioecious, meaning that male and female flowers are on separate plants. Flowers occur in groups of four to eight in tight clusters surrounded by small bracts. The yellowish green petals are narrowly inverse lance-shaped and 0.1 in (0.25 cm) long. The fleshy, round fruit contains a single seed. This species is distinguished from others in the genus by the hairiness of the lower leaf surface and the shape of the leaf base. In addition, the hairy leaves distinguish this species from all other species of Myrsine on Oahu.

M. juddii was first described in 1940 from a specimen collected in the Koolau Mountains. Otto and Isa Degener, in an action in the 1970s not supported by other taxonomists, transferred this species from Myrsine to the genus Rapanea. The concept of Myrsine is currently followed. The specific epithet honors Albert Judd, who had a keen interest in conservation of the native Hawaiian flora.

Habitat

M. juddii typically grows in wet forests dominated by 'ohi'a or a mixture of 'ohi'a and uluhe at elevations between 1,900 and 2,820 ft (579 and 860 m). Associated plant taxa include 'uki, 'olapa, kolokolo mokihana, kopiko, 'ohi'a ha, and the endangered plant Chamaesyce rockii.

Distribution

M. juddii has been reported from only three populations in the central Koolau Mountains—the North Kaukonahua-Kahana Summit divide, Peahinaia Trail, and Puu Kainapuaa to Poamoho Trail. These populations are found on private and state land leased by the Department of Defense for Kawailoa Training Area. The total number of plants in 1997 was estimated at between 500 and 3,000 individuals; all but five to ten of these occurred in a single, poorly defined population.

Threats

The primary threats to M. juddii are habitat degradation and destruction by feral pigs, potential impacts from military activities, competition with alien plants such as Koster's curse and strawberry guava, and risk of extinction from natural events or reduced reproductive vigor due to the small number of extant populations.

The noxious shrub Koster's curse is a threat to this endangered plant, as are the dense stands formed by strawberry guava.

Populations of M. juddii that occur on land leased and owned by the U. S. Army face the threat of being damaged through military activity, either by troops in training maneuvers or by the construction, maintenance, and utilization of helicopter landing and drop-off sites.

Conservation and Recovery

The National Tropical Botanical Garden has collected seed from this species, but M. juddii has not been propagated.

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
(503) 231-6121
http://pacific.fws.gov/

Reference

U.S. Fish and Wildlife Service. 1998. "Recovery Plan for Oahu Plants." U.S. Fish and Wildlife Service, Portland, Oregon. 207 pp., plus appendices.