Kuahiwi Laukahi

Plantago hawaiensis

Description

Kuahiwi laukahi (Plantago hawaiensis ) is a perennial herb which grows from a stout, short stem. This species has thick, leathery, narrowly oval or oblong leaves located at the base of the plant, which measure 3-8.7 in (7.6-22.1 cm) long and usually 0.6-1.3 in (1.5-3.3 cm) wide. The flowering stalk is 7.9-35 in (20.1-88.9 cm) long and is topped by a spike usually 5.9-9.0 in (14.9-22.9 cm) long. Each upward pointing flower, subtended by a single bract 0.08-0.1 in (2.0-2.5 mm) long, has a four-lobed calyx 0.06-0.09 in (1.5-2.3 mm) long, and a trumpet-shaped corolla about 0.04 in (1.0 mm) long. The capsule, 0.1-0.2 in (2.5-5.1 mm) long and projecting from the calyx, opens to release four to six dull black seeds about 0.04 in (1.0 mm) long and winged on one end. This species is distinguished from other endemic and naturalized species of the genus in Hawaii by its perennial herbaceous habit, thick leathery leaves, upward pointing flowers, and capsules that project from the calyx.

Habitat

The habitat of P. hawaiensis is somewhat variable. The taxon grows either in montane wet sedgeland with mixed sedges and grasses, or in montane mesic forest growing with stunted Acacia koa and Metrosideros polymorpha ('ohi'a) often growing in cracks of lava. P. hawaiensis occurs at elevations of 5,900-8,040 ft (1,798-2,451 m) mainly on the leeward side of the island.

Distribution

Historically, this species was found only on the island of Hawaii on the southern slope of Mauna Kea; the northeastern, southeastern, and southern slopes of Mauna Loa; and the western slope of Hualalai.

Since 1975, eight populations have been identified in North and South Hilo, Waiakea Forest Reserve, Hawaii Volcanoes National Park, Kapapala and Puu Waawaa. The populations are found on state, federal, and privately owned lands. The total number of individuals present is not known; however, estimates exceed 5,000. Two plants were discovered in Puu Waawaa around 1990, and the presence of additional plants is suspected. The Volcanoes Park populations are flowering, fruiting, and reproducing. A few scattered plants have been observed in the Upper Waiakea Forest Reserve near Powerline Road and the Ka'u Silversword Bog.

Threats

Feral goats and mouflon sheep are problems for the two populations that occur on Kipuka Kulalio and Kipuka Mauna'iu in Hawaii Volcanoes National Park. These individuals grow at an elevation of 7,000 ft (2,134 m). They occupy an area outside the Mauna Loa strip goat fence and, therefore, are unprotected from these feral animals. Browsing by goats and mouflon sheep may affect the viability of these plants, preclude the establishment of juveniles, and damage the habitat, thereby opening suitable sites for the inevitable establishment of alien weeds.

Reproductive ability may be decreased because of limited numbers of individuals in most populations and widely scattered distribution of these few populations, resulting in the demise of the taxon. Random extinction from natural phenomena and human interference is possible.

Conservation and Recovery

The National Tropical Botanic Garden has propagated the taxon. Four plants are located at the greenhouse at Hawaii Volcanoes National Park.

Steps should be taken to fence known populations in order to protect them from ungulates and to encourage regeneration. Research as to additional causes for decline may also be necessary. Ownership of the large population at Kapapala should be determined and the site protected.

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/

Senior Resident Agent Office
U.S. Fish and Wildlife Service
300 Ala Moana Boulevard, Room 7-235
P.O. Box 50223
Honolulu, Hawaii 96850-5000
Telephone: (808) 541-2681
Fax: (808) 541-3062

Reference

U.S. Fish and Wildlife Service. 4 March 1994. "Endangered and Threatened Wildlife and Plant; Determination of Endangered or Threatened Status for 21 Plants from the Island of Hawaii, State of Hawaii." Federal Register 59 (43): 10305-10325.