Search / Plant Profile / Mezoneuron kavaiense

Plant Profile

Uhiuhi (Mezoneuron kavaiense)

Full view of young tree. Photo Credit: Jill Shimatsu

Global Rank: G1 - Critically Imperiled
Legal Status: Federally Endangered
Family: Fabaceae
State: HI
Nature Serve ID: 133812
Lifeform: Shrub, Tree
Date Inducted in National Collection: 05/28/1986

Description:

There are four Caesalpinia species in Hawaii, three introduced and one endemic. Caesalpinia kavaiensis, or uhiuhi, was once fairly abundant on the islands of Hawaii, Oahu, Kauai, and Maui. The wood of C. kavaiensis is highly valued for its color, grain, and density. Hawaiians made spears with the wood and also a fishing implement known as laau melomelo or laau maklei. The past cutting of trees for these uses is likely not the contributing factor to its decline and current endangered status, as numbers have more recently declined as a result of grazing by introduced cattle, goats and sheep. However, because populations are now so small (only 32 individuals remain), the loss of even one tree for any purpose brings the species precipitously close to extinction. C. kavaiensis, a member of the pea family (Fabaceae), is a tree that can grow up to 10 meters (33 ft) tall, with trunks that have dark gray bark with rough rectangular or oblong plates. The flowers are perfect (with both male and female organs) with a pink to rose calyx and red anthers borne in terminal racemes that are pink to red in color. C. kavaiensis has pink seedpods that are winged on one side, making this a very attractive tree. (Wagner et al. 1999)

Where is Uhiuhi (Mezoneuron kavaiense) located in the wild?

Habitat:

C. kavaiensis is restricted to dry or mesic forests between 80 to 920 meters (262 to 3,018 ft) elevation. (Wagner et al. 1999)Associated species of C. kavaiensis include Dodonaea viscosa (aalii), Diospyros sandwicense (lama), and Canthium odoratum (alahee).

Distribution:

C. kavaiensis, an endemic tree to the Hawaiian Islands, was once widespread on the islands of Kauai (Waimea Canyon), Oahu (Waianae Mountains), west Maui, North Kona District, Hawaii, and Lana`i. Today

States & Provinces:

Uhiuhi can be found in Hawaii

Which CPC Partners conserve Uhiuhi (Mezoneuron kavaiense)?

National Tropical Botanical Garden

Not Sponsored

Assigned 06/09/17

Harold L. Lyon Arboretum

Not Sponsored

Assigned 07/24/23

CPC's Plant Sponsorship Program provides long term stewardship of rare plants in our National Collection. We are so grateful for all our donors who have made the Plant Sponsorship Program so successful. We are in the process of acknowledging all our wonderful plant sponsorship donors on our website. This is a work in progress and will be updated regularly.

Conservation Actions

Nature Serve Biotics

05/02/2017

Recorded from Kauai, Oahu, Maui, Lanai, and Hawaii, but known to be extant only on Oahu and Hawaii. There have been no records of the species on Maui for more than half a century. The last known plants on Kauai and Lanai died recently (in the 1990's). On Oahu and Hawaii a total of fewer than 100 plants are known to remain. Successful recruitment does not presently occur at most sites. Rats are reported to feed heavily on the seeds at some locations. The populations on Hawaii Island are in areas that have been affected by urbanization, agriculture, and fire. As with most native Hawaiian dry and moist forest plants, the species is threatened by alien plants and animals.

01/01/2010

Threats to C. kavaiensis include habitat degradation by grazing cattle, mouflon, axis deer, and feral goats. Additional threats include urban development, fires, and invasion of exotic plants, rodents, exotic insects such as the coffee twig borer (Xylosan

01/01/2010

Less than 20 individuals total are found in in 2 populations on the Big Island Less than 10 individuals total in 2 populations on Oahu Two individuals in 1 population on Kauai FROM NTBG: Nos. of Pop: 5 (Center for Plant Conservation [CPC] 2002) Nos. of Plants: <32 (CPC 2002)

01/01/2010

C. kavaiensis plants, both wild and cultivated produce viable seed. The Division of Forestry and Wildlife, Hawaii Department of Land and Natural Resources (DOFAW) occasionally collects seeds from the wild and propagated plants in Hilo nursery. The seedlings are then transplanted into fenced enclosures where they are supported by watering and weed control (USFWS 1994). Seeds of C. kavaiensis have been tested by the Center for Conservation Research and Training (CCRT), finding that they are orthodox and can tolerate freezing and drying. The laboratory germination time was one to three weeks (Yoshinaga 2002).

01/01/2010

Management goals for C. kavaiensis include reducing current threats such as fire, damage by herbivores, to make habitat improvements, and to encourage natural re-generation. Outplanting nursery-raised trees are also a part of management goals. Management strategies are focused on fenced exclosures. The fences protect trees from browsing cattle and feral ungulates. They are designed to be large enough for expansions in populations. Fire breaks and fire roads outside the protected areas have been cleared to protect and to give access to the enclosures. Fountain grass removal also increases the probability of regeneration and seedling establishment (USFWS 1994). The National Tropical Botanical Garden (NTBG) currently has ex situ holdings of 1,160 seeds in its seed bank, which represents four out of the five populations. In addition, there are five plants growing in the nursery and 11 plants in the botanical garden representing two populations.

01/01/2010

1. Prevent the destruction of the few remaining wild trees of C. kavaiensis 2. Remove the environmental factors that may prevent natural regeneration and dispersal of C. kavaiensis (ex. control alien species such as fountain grass, insect control and feral ungulate control). 3. Conduct research on limiting factors of C. kavaiensis. 4. Augmenting current populations of C. kavaiensis. 5. Validate and revise recovery objectives for C. kavaiensis. 6. Map genetic diversity in the surviving populations of C. kavaiensis. 7. Conduct pollination biology and seed dispersal studies. Recommendations derived from M.H. Chapin, M. Maunder, Center for Plant Conservation [CPC] (2002), and USFWS (1994).

01/01/2010

1. Develop proper horticultural protocols and pest management for C. kavaiensis 2. Establish secure ex situ stocks with full founder representation. 3. Survey ex situ holdings and conduct molecular fingerprinting. Recommendations derived from M.H. Chapin and M. Maunder.