Alani (Melicope knudsenii)

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Melicope knudsenii

ListedFebruary 25, 1994
FamilyRutaceae (Citrus)
DescriptionMedium-sized tree with smooth gray bark, yellowish-brown to olive-brown hairs on the tips of the branches, and densely hairy flowers that cluster in the leaf axils.
HabitatLowland dry forests.
ThreatsCattle, goats, pigs, alien plants, low populations.


This alani (Melicope knudsenii ), a member of the citrus family, ranges in height from 10-33 ft (3-10 m) and has smooth gray bark and yellowish-brown to olive-brown hairs on the tips of the branches. The leaves, which vary from oblong to elliptic, are 3.5-9.8 in (8.9-24.9 cm) long and 1.8-3.9 in (4.6-9.9 cm) wide. The lower surface of the leaves is uniformly covered with olive-brown hairs, but the upper surface is only sparsely hairy along the midrib.

The densely hairy flowers are bisexual or may be unisexual. There are usually 20-200 flowers per cluster in the leaf axils. The sepals and petals are covered with silky gray hairs, and the sepals persist in the fruit. The fruits, 0.7-1.2 in (1.8-3 cm) wide, are comprised of distinct follicles that reach lengths of 0.3-0.6 in (7.6-15.2 mm). The hairless exocarp is dotted with minute glands. The endocarp also lacks hairs. Seeds number one or two per carpel (ovule-bearing structure) and are about 0.2 in (5.1 mm) long. The distinct carpels of the fruit, the hairless endocarp, the larger number of flowers per cluster, and the distribution of hairs on the underside of the leaves distinguish this species from others in the genus.


M. knudsenii grows on forested flats or talus slopes in lowland dry to mesic forests at elevations of about 1,500-3,300 ft (457-1,006 m). The lowland dry forests where this species grows are well-drained and have highly weathered substrates rich in aluminum. They are also characterized by mostly winter rainfalls of 20-80 annual in (50.8-203.2 cm). The Auwahi population on Maui grows on a substrate of 'a'a lava in a remnant native forest dominated by a continuous mat of kikuyu grass. Plants associated with the Kauai populations include 'a'ali'i, hame, 'ohi'a, and Xylosma.


Historically, this species was known only from the southeast slope of Haleakala on Maui and from Olokele Canyon on Kauai. It remains in the Auwahi and Kanaio areas of Maui on privately owned land, but its numbers have decreased from being very common in 1920 to having only 20-30 plants at the time of its last observation in 1983.

Four populations of one individual each remain on state land in Kauai. Three populations in the Koaie drainage area of Waimea Canyon are distributed across a distance of 1.6 mi (2.6 km); the fourth population is a single individual in the upper Kuia Valley. The total population numbers around 24-34 individuals.


Competition with alien plants and habitat degradation by feral and domestic animals are the major threats affecting M. knudsenii. On Kauai, this species competes with lantana and is affected by feral goats and pigs; on Maui, the species grows in an area currently grazed by domestic cattle, where a continuous mat of kikuyu grass prevents seedlings from becoming established.

Conservation and Recovery

The major threats to M. knudsenii are habitat destruction by feral animals and competition with alien plant taxa. On Kauai, feral goats and pigs destroy habitats, while weeds such as daisy fleabane and prickly Florida blackberry compete with the species.

The recovery of this species depends on how well management practices can be implemented. The habitat of this and other Hawaiian species has undergone extreme alteration because of past and present land management practices, including the deliberate introduction of alien animals and plants and increased agricultural and recreational development. To understand the recovery problems facing this species, it is necessary to understand the long-term causes of habitat destruction.


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

Pacific Remote Islands Ecological Services Field
300 Ala Moana Blvd., Room 3-122
P.O. Box 50088 Honolulu,
Hawaii 96850
Telephone: (808) 541-1201
Fax: (808) 541-1216


U. S. Fish and Wildlife Service. 25 February 1994. "Endangered and Threatened Wildlife and Plants; Determination of Endangered or Threatened Status for 24 Plants from the Island of Kauai, HI." Federal Register 59 (38): 9304-9329.