Popolo 'aiakeakua

Solanum sandwicense

Description

Popolo 'aiakeakua (Solanum sandwicense ) is a large sprawling shrub in the nightshade family (Solanaceae) that grows up to 13 ft (4 m) high. The younger branches are more densely hairy than older branches. The oval leaves are usually 4-6 in (10-15 cm) long and 2-5.5 in (5-14 cm) wide and have up to four lobes along the margins. Leaf stalks are 0.8-1.6 in (2-4 cm) long. On the flowering stem, a few to as many as 40 flowers are grouped in threes, with each flower on a stalk that is about 0.6 in (1.5 cm) long and is bent at the end so that the flower faces downward. The corolla is white with a faint purplish stripe, and each lobe is curved somewhat backward. Stamens are attached low on the corolla tube, with anthers curved inward. The fruit is a berry 0.5-0.6 in (1.3-1.5 cm) in diameter and black when ripe. This species differs from others in the genus in having dense hairs on young plant parts, a greater height, and its lack of prickles.

Habitat

S. sandwicense is typically found in open, sunny areas at elevations of 2,500-4,000 ft (760-1,220 m) in diverse lowland to montane mesic forests, and occasionally in wet forests. Associated vegetation includes koa, 'ohi'a, uluhe, and wet forest plants such as kopiko, ho'i'o, and the more common Melicope species (alani).

Distribution

S. sandwicense was known historically from widely scattered populations throughout the Waianae Mountains and southern portions of the Koolau Mountains on the Hawaiian island of Oahu. On the island of Kauai, this species was known from locations in the Kokee regions bounded by Kalalau Valley to the north, Milolii Ridge to the west, and Kawaikoi to the east, extending southward to the Hanapepe River.

This species is now known on Oahu from a single population on privately owned land in what is now Honouliuli Preserve. One other population was destroyed by a landslide in 1986. The Kauai populations are on private and state land and most are from Kokee and Na Pali Coast State Park. Of the 12 known historical populations, only four are currently extant; these number about 20 plants.

Threats

The major threats to populations on Kauai are habitat degradation by feral pigs and competition with alien plants, especially banana poka, prickly Florida blackberry, strawberry guava, kahili ginger, and Japanese honeysuckle. S. sandwicense is also threatened by fire, overcollecting by scientists, and stochastic extinction and reduced reproductive vigor as a result of limited numbers.

All Oahu populations except one are now apparently extinct, the result of habitat being destroyed by urbanization, landslides, feral pigs, and alien weeds.

Conservation and Recovery

S. sandwicense has been successfully propagated and then cultivated by the Lyon Arboretum, the National Tropical Botanical Garden, and the Waimea Arboretum. Holdings at Lyon Arboretum through 1995 consisted of 12 plants in the tissue culture lab. Through the same year, the National Tropical Botanical Garden had seeds in short-term storage as well as plants growing in their garden, while Waimea Arboretum had two plants.

In the late 1990s, the Kauai District of the State of Hawaii's Division of Forestry and Wildlife completed fencing in Kuia National Area Reserve; this fencing will protect the S. sandwicense population there.

The Nature Conservancy of Hawaii is planning on outplanting approximately 10 seedlings of this species in Honoutiuli Preserve on Oahu.

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/

Reference

U. S. Fish and Wildlife Service. 1995. "Recovery Plan for the Kauai Plant Cluster." U. S. Fish and Wildlife Service, Portland, Oreg. 270 pp.