Neraudia Sericea

views updated

Neraudia sericea

No Common Name

StatusEndangered
ListedNovember 10, 1994
FamilyUrticaceae (Nettle)
DescriptionShrub with densely hairy branches and elliptic or oval leaves.
HabitatLowland dry to mesic shrubland or forest.
ThreatsHabitat degradation by feral pigs and goats; competition with the alien plant molasses grass; low numbers.
RangeHawaii

Description

Neraudia sericea, a member of the nettle family, is a shrub with densely hairy branches that reaches a height of 10-16 ft (3-5 m). The elliptic or oval leaves are 1.7-5.1 in (4.3-13 cm) long and have smooth margins or slightly toothed margins on young leaves. The upper leaf surface is moderately hairy, while the lower leaf surface is densely covered with irregularly curved, silky, gray to white hairs up to 0.04 in (1 mm) long along the veins. The male flowers may be stalkless or have short stalks. The female flowers are stalkless and have a densely hairy calyx that is either toothed, collarlike, or divided into narrow and unequal segments. The fruits are achenes, 0.04 in (1 mm) long, with the apical section separated from the basal portion by a deep constriction. Seeds are oval with a constriction across the upper half. N. sericea differs from the other four closely related species of this endemic Hawaiian genus by the density, length, color, and posture of the hairs on the lower leaf surface and by the mostly entire leaf margins.

N. sericea was published in 1851. It was reduced to a variety of N. melastomaefolia (N. melastomaefolia var. sericea ) in 1888. It was also described N. kahoolawensis, a new species treatment for a specimen collected by J.M. Lydgate on the island of Kahoolawe. In the most current treatment in 1990, the reduction of N. sericea to a variety of N. melastomaefolia is not accepted, and N. kahoolawensis is considered a Kahoolawe population of N. sericea.

Habitat

N. sericea generally occurs in lowland dry to mesic shrubland or forest at elevations of 2,200-4,500 ft (671-1,372 m). Other associated plant species include 'ilima, lama, Bobea ('ahakea), Coprosma (pilo), and Hedyotis.

Distribution

N. sericea was known historically from Kamalo and near Waianui on Molokai; from Kaiholena on central Lanai; from Olowalu Valley on West Maui; from the southern slopes of Haleakala on East Maui; and from an unspecified site on Kahoolawe.

Three populations of this species were extant in 1995. A population of 50-100 individuals occurred on Molokai in an area of more than 1,080 sq ft (100.3 sq m) on private land below Puu Kolekole, specifically along the bottom and lower slopes of Makolelau Gulch. West Maui had a population of undetermined size on private land at Pohakea Gulch, and East Maui had a population of two individuals on state land in the Kahikinui area.

Threats

The primary threats to N. sericea are habitat degradation by feral pigs and goats, competition with the alien plant molasses grass, and reduced reproductive vigor or stochastic extinction due to the small number of existing populations and individuals.

Two populations of N. sericea on Molokai are threatened by pigs; another population on the same island is presently threatened by goats.

N. sericea is not known to be unpalatable to cattle and deer; as such, predation is a probable threat to this plant at sites where these animals have been reported.

At least one population of N. sericea on Molokai is being harmed by molasses grass.

Conservation and Recovery

Living Indigenous Forest Ecosystems, a community-based nonprofit corporation, manages conservation lands at Kahikinui Forest Reserve; in July 1997 this organization fenced a portion of the forest reserve that harbors a population of N. sericea. Plans also include ungulate removal and forest restoration. Follow-up monitoring will be conducted annually or biannually. This action is expected to enhance conservation of the N. sericea plants growing there.

More than 1,000 seeds were in storage in 1997 at the National Tropical Botanical Garden. Seed germination tests show a germination rate of only 2% for fresh seeds; no germination of seeds occurred after a minimum of 45 days in storage.

Contacts

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/

Pacific Remote Islands Ecological Services Field Office
300 Ala Moana Blvd., Room 3-122
P.O. Box 50088
Honolulu, Hawaii 96850
Telephone: (808) 541-3441
Fax: (808) 541-3470

Reference

U. S. Fish and Wildlife Service. 10 November 1994. "Endangered Status for 12 Plants from the Hawaiian Islands." Federal Register 59 (217): 56333-56351.