Colubrina oppositifolia, known as Kauila in Hawaiian

Hawaiian language

The Hawaiian language is a Polynesian language that takes its name from Hawaii, the largest island in the tropical North Pacific archipelago where it developed. Hawaiian, along with English, is an official language of the state of Hawaii...

, is a species of flowering

Flowering plant

The flowering plants , also known as Angiospermae or Magnoliophyta, are the most diverse group of land plants. Angiosperms are seed-producing plants like the gymnosperms and can be distinguished from the gymnosperms by a series of synapomorphies...

 tree

Tree

A tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to...

 in the buckthorn

Buckthorn

The Buckthorns are a genus of about 100 species of shrubs or small trees from 1-10 m tall , in the buckthorn family Rhamnaceae...

 family, Rhamnaceae

Rhamnaceae

Rhamnaceae, the Buckthorn family, is a large family of flowering plants, mostly trees, shrubs and some vines.The family contains 50-60 genera and approximately 870-900 species. The Rhamnaceae have a worldwide distribution, but are more common in the subtropical and tropical regions...

, that is endemic to Hawaii

Hawaii

Hawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...

. It can be found in dry

Hawaiian tropical dry forests

The Hawaiian tropical dry forests are a tropical dry broadleaf forest ecoregion in the Hawaiian Islands. They cover an area of on the leeward side of the main islands and the summits of Niihau and Kahoolawe. These forests are either seasonal or sclerophyllous. Annual rainfall is less than and...

, coastal mesic, and mixed mesic forests at elevations of 240–920 m (787.4–3,018.4 ft) on the islands of Oahu

Oahu

Oahu or Oahu , known as "The Gathering Place", is the third largest of the Hawaiian Islands and most populous of the islands in the U.S. state of Hawaii. The state capital Honolulu is located on the southeast coast...

 (Waianae Range

Waianae Range

Waianae Range is the eroded remains of an ancient shield volcano that comprises the western half of the Hawaiian Island of Oahu...

) and Hawaii

Hawaii (island)

The Island of Hawaii, also called the Big Island or Hawaii Island , is a volcanic island in the North Pacific Ocean...

 (slopes of Kohala

Kohala (mountain)

Kohala is the oldest of five volcanoes that make up the island of Hawaii. Kohala is an estimated one million years old—so old that it experienced, and recorded, a reversal of magnetic field 780,000 years ago. It is believed to have breached sea level more than 500,000 years ago and to...

, Hualālai

Hualalai

Hualālai is a dormant shield volcano on the island of Hawaii in the Hawaiian Islands. It is the third-youngest and the third most active of the five volcanoes that form the island of Hawaii, following Kīlauea and the much larger Mauna Loa, and also the westernmost. Its peak is above sea...

, and Mauna Loa

Mauna Loa

Mauna Loa is one of five volcanoes that form the Island of Hawaii in the U.S. state of Hawaii in the Pacific Ocean, and the largest on Earth in terms of volume and area covered. It is an active shield volcano, with a volume estimated at approximately , although its peak is about lower than that...

). There is also one individual remaining on Maui

Maui

The island of Maui is the second-largest of the Hawaiian Islands at and is the 17th largest island in the United States. Maui is part of the state of Hawaii and is the largest of Maui County's four islands, bigger than Lānai, Kahoolawe, and Molokai. In 2010, Maui had a population of 144,444,...

. Associated plants include alahee (Psydrax odorata

Psydrax odorata

Psydrax odorata, known as Alahee in Hawaiian, is a species of flowering shrub or small tree in the coffee family, Rubiaceae, that is native to the Pacific Islands, Malesia and Australasia...

) and ohe kukuluāeo (Reynoldsia sandwicensis

Reynoldsia sandwicensis

Reynoldsia sandwicensis, known as Ohe kukuluāeo in Hawaiian, is a species of flowering plant in the ivy family, Araliaceae, that is endemic to Hawaii. It is a tree, reaching a height of high with a trunk diameter of...

).

Description

This tree reaches a height of 5–13 m (16.4–42.7 ft). The trunk is coated in shredding gray-brown bark and the smaller twigs are reddish. The leaves are oppositely arranged and have pointed oval blades. The yellow-green flowers occur in clusters of 10 to 12. The fruit is a rounded capsule which is explosively dehiscent

Dehiscence (botany)

Dehiscence is the opening, at maturity, in a pre-defined way, of a plant structure, such as a fruit, anther, or sporangium, to release its contents. Sometimes this involves the complete detachment of a part. Structures that open in this way are said to be dehiscent...

.

Uses

Native Hawaiians

Native Hawaiians

Native Hawaiians refers to the indigenous Polynesian people of the Hawaiian Islands or their descendants. Native Hawaiians trace their ancestry back to the original Polynesian settlers of Hawaii.According to the U.S...

 valued the hard wood of C. oppositifolia and that of a related species, Alphitonia ponderosa

Alphitonia ponderosa

Alphitonia ponderosa is a species of flowering tree in the buckthorn family, Rhamnaceae, that is endemic to the Hawaiian Islands. It is locally known as kauila, as is the related Colubrina oppositifolia.-Description:A...

, both of which were known as kauila

Kauila

Kauila refers to two species of trees in the buckthorn family, Rhamnaceae, that are endemic to Hawaii: Alphitonia ponderosa and Colubrina oppositifolia. Their wood was prized for being extremely hard, and is so dense that it sinks in water. Both occur in dry to mesic forest and are now rare; C....

. Consequently, the exact usage of C. oppositifolia wood is unknown. It is believed to have been used in pou (house posts), hohoa (round kapa

Kapa

Kapa is a fabric that was made by Native Hawaiians from the bast fibres of certain species of trees and shrubs in the orders Rosales and Malvales. It is similar to tapa found elsewhere in Polynesia but differs in the methods used in its creation...

 beaters), ie kūkū (square kapa beaters), ō (harpoon

Harpoon

A harpoon is a long spear-like instrument used in fishing to catch fish or large marine mammals such as whales. It accomplishes this task by impaling the target animal, allowing the fishermen to use a rope or chain attached to the butt of the projectile to catch the animal...

s), hia kā upena (fishing net

Fishing net

A fishing net or fishnet is a net that is used for fishing. Fishing nets are meshes usually formed by knotting a relatively thin thread. Modern nets are usually made of artificial polyamides like nylon, although nets of organic polyamides such as wool or silk thread were common until recently and...

 shuttles

Shuttle (weaving)

A shuttle is a tool designed to neatly and compactly store weft yarn while weaving. Shuttles are thrown or passed back and forth through the shed, between the yarn threads of the warp in order to weave in the weft....

), ihe pahee (javelin

Javelin

A Javelin is a light spear intended for throwing. It is commonly known from the modern athletic discipline, the Javelin throw.Javelin may also refer to:-Aviation:* ATG Javelin, an American-Israeli civil jet aircraft, under development...

s), pololū (spear

Spear

A spear is a pole weapon consisting of a shaft, usually of wood, with a pointed head.The head may be simply the sharpened end of the shaft itself, as is the case with bamboo spears, or it may be made of a more durable material fastened to the shaft, such as flint, obsidian, iron, steel or...

s), pāhoa (dagger

Dagger

A dagger is a fighting knife with a sharp point designed or capable of being used as a thrusting or stabbing weapon. The design dates to human prehistory, and daggers have been used throughout human experience to the modern day in close combat confrontations...

s), lāa pālau (club

Club (weapon)

A club is among the simplest of all weapons. A club is essentially a short staff, or stick, usually made of wood, and wielded as a weapon since prehistoric times....

s), leiomano

Leiomano

The leiomano is a shark-toothed club used by various Polynesian tribes, but mostly by the native Hawaiians.Leiomano is a word in the Hawaiian language and may have been derived from lei o manō, which means "a shark's lei."...

 (shark tooth

Shark tooth

A shark tooth is one of the numerous teeth of a shark. Sharks continually shed their teeth, and some Carcharhiniformes shed approximately 35,000 teeth in a lifetime. In some geological formations, shark's teeth are a common fossil...

 clubs), ōō (digging stick

Digging stick

In archaeology and anthropology a digging stick is the term given to a variety of wooden implements used primarily by subsistence-based cultures to dig out underground food such as roots and tubers or burrowing animals and anthills...

s), pieces for ume (a wand game), and ūkēkē

Ukeke

The ūkēkē is a musical bow made of koa wood, 16 to 24 inches long and about 1½ inches wide with two or three strings fastened through and around either end, tuned to an A major triad. Prior to the introduction of steel strings, gut or sennit were used.The strings were strummed with one hand...

 (musical bow

Musical bow

The musical bow is a simple string musical instrument most archaic cultures as well as in many in the present day. It consisting of a string supported by a flexible stick 1.5 to 10 feet long, and strung end to end with a taut cord. Usually made out of wood...

s).

Conservation

This tree has become rare in the wild. Once a dominant species

Dominance (ecology)

Ecological dominance is the degree to which a species is more numerous than its competitors in an ecological community, or makes up more of the biomass...

 of the forests it inhabits, it has now been reduced to no more than 300 wild individuals. Threats to the species have included introduced plant species

Introduced species

An introduced species — or neozoon, alien, exotic, non-indigenous, or non-native species, or simply an introduction, is a species living outside its indigenous or native distributional range, and has arrived in an ecosystem or plant community by human activity, either deliberate or accidental...

, feral pigs and goats

Feral goat

The feral goat is the domestic goat when it has become established in the wild. Feral goats occur in Australia, New Zealand, Ireland, Great Britain, Hawaii, the Galapagos and in many other parts of the world...

, rat

Rat

Rats are various medium-sized, long-tailed rodents of the superfamily Muroidea. "True rats" are members of the genus Rattus, the most important of which to humans are the black rat, Rattus rattus, and the brown rat, Rattus norvegicus...

s, and the black twig borer (Xylosandrus compactus). The hard wood made it valuable to people, who overharvested

Overexploitation

Overexploitation, also called overharvesting, refers to harvesting a renewable resource to the point of diminishing returns. Sustained overexploitation can lead to the destruction of the resource...

 it. This is a federally listed endangered species

Endangered species

An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...

of the United States.

External links