Haha (Cyanea longiflora)
|Listed||October 10, 1996|
|Description||Unbranched shrub with woody stems with five to ten flowers per stalk and pear-shaped berries.|
|Habitat||Steep slopes or ridge crests in mesic koa-'ohi'a forest in the Waianae Mountains or wet 'ohi'a-uluhe forest in the Koolau Mountains.|
|Threats||Habitat degradation and destruction by feral pigs, potential impacts from military activities, potential predation by rats, competition with alien plants, and fire.|
Cyanea longiflora, a member of the bellflower family, is an unbranched shrub with woody stems 3.5-10 ft (1-3 m) long. The leaves are elliptic or inversely lance-shaped, 12-22 in (30.5-55.8 cm) long and 2.4-4.7 in (6-12 cm) wide. Mature leaves have smooth or hardened leaf edges with shallow, ascending, and rounded teeth. The flowering stalks are five-to ten-flowered and 1.2-2.4 in (3-6 cm) long. The calyx lobes are fused into an irregularly toothed sheath 0.08-0.2 in (0.2-0.5 cm) long. The petals, 2.4-3.5 in (6-9 cm) long, and the hairless staminal column are dark magenta. The berries are almost pear-shaped. C. longiflora differs from others in this endemic Hawaiian genus by the fused calyx lobes.
C. longiflora was first collected on Oahu, then named Rollandia longiflora by Dr. Heinrich Wawra in 1873. Other names considered synonymous with Rollandia longiflora are R. lanceolata var. brevipes and R. sessilifolia.
The new combination C. longiflora was published in 1993. The specific epithet refers to the long flowers.
C. longiflora usually is found on steep slopes or ridge crests in mesic koa-'ohi'a forest in the Waianae Mountains or wet 'ohi'a-uluhe forest in the Koolau Mountains, usually at elevations between 2,030 and 2,560 ft (619 and 780 m). Associated plant taxa in koa-'ohi'a forest include hame, kopiko, uluhe, Coprosma sp. (pilo), and Syzygium sp. (ha). In wet 'ohi'a-uluhe forest, associated native taxa include 'akia, alani, Cibotium sp. (hapu'u), Dubautia sp. (na'ena'e), Hedyotis sp., and Pittosporum sp. (ho'awa).
C. longiflora was known historically on Oahu from five populations in the Waianae Mountains and six populations in the Koolau Mountains. Only five populations of this species are extant: Pahole Gulch, Makaha Valley, and Makaha-Waianae Ridge in the Waianae Mountains, as well as Kawainui Drainage and Opaeula Gulch in the Koolau Mountains. These five populations total between 220 and 300 plants. The Pahole Gulch population contains more than 200 individuals, while the remaining two populations contain fewer than ten individuals. These occurrences are found on City and County of Honolulu land, private land leased by the Department of Defense for the Kawailoa Training Area, and state-owned land that includes territory on Pa-hole National Area Reserve.
The major threats to C. longiflora are habitat degradation and destruction by feral pigs, potential impacts from military activities, potential predation by rats, competition with the alien plants strawberry guava and prickly Florida blackberry in the Waianae Mountains and Koster's curse in the Koolau Mountains, potential fire, and a risk of extinction from naturally occurring events or through the reduced reproductive vigor so prevalent in very small and widely dispersed populations.
C. longiflora is potentially threatened by feral pig predation because the species is not known to be unpalatable to pigs, who favor plants from the bell-flower family for food.
It is possible that rats eat the fruit of C. longiflora, a plant with fleshy stems and fruit that grows in areas where rats occur.
The noxious shrub Koster's curse and the noxious weed prickly Florida blackberry are significant threats to C. longiflora. Dense stands of strawberry guava also threaten this listed plant.
Populations of C. longiflora 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.
Fire is also a potential threat to C. longiflora, which occurs in dry or mesic habitats where seasonal conditions exist for the easy spread of fire.
Conservation and Recovery
Fencing and removal of feral pigs in the Pahole drainage was completed by Division of Forestry and Wildlife in July 1997. Weeding of strawberry guava, Christmas berry, and Koster's curse continues in the surrounding areas. Plants in the Pahole drainage have been measured and mapped, and seeds have been collected from plants outside the fence for nursery cultivation and reintroduction into the fenced areas. This species is also being propagated at the Lyon Arboretum and the National Tropical Botanical Garden.
U. S. Fish and Wildlife Service
Regional Office, Division of Endangered Species
Eastside Federal Complex
911 N. E. 11th Ave.
Portland, Oregon 97232-4181
U. S. Fish and Wildlife Service. 1998. "Recovery Plan for Oahu Plants." U. S. Fish and Wildlife Service, Portland, Oregon. 207 pp., plus appendices.