Acacia koaia
Encyclopedia
Acacia koaia, known as koaia or koaie in Hawaiian
, is a tree
in the pea
family
, Fabaceae
, that is endemic to Hawaii
. It is closely related to koa (A. koa), and is sometimes considered to be the same species. Koaia is usually distinguished by growing as a short (rarely more than 5 m (16.4 ft)), broad, gnarled tree; having the seed
s longitudinally arranged in the pod; shorter, straighter phyllodes; and much denser wood. A population on the northern coast of Kauai
may be intermediate, but the relationships have not been worked out. Koaia wood is claimed to be very different from that of koa, and this may be the best character to separate them.
Koaia is highly adapted to dry habitats, and is capable of forming dense forests in areas with very little rainfall. It was formerly found widely in dry forests
on all of the main islands. Associated plants include uluhe (Dicranopteris linearis
), hala (Pandanus tectorius
), kookoolau (Bidens
spp.), kokio (Hibiscus kokio
), nehe (Lipochaeta
spp.), hala pepe (Pleomele
spp.), and ōhia lehua (Metrosideros polymorpha
). Like many legumes, koaia is able to fix nitrogen
. However, it has been devastated by cattle
and other ungulate
s and is now rare. It can be seen on ranch land in North Kohala
, and at a small fenced exclosure outside of Waimea known as the koaia sanctuary. Koaia is one of the species being used to revegetate the island of Kahoolawe
, which lost most of its plant life to overgrazing
and ordnance testing.
ground koaia leaves and bark with auaukoi (Senna
occidentalis
) and kikānia pipili (Desmodium
sandwicense) stalks. The mixture was then hydrated and used in a steam bath to treat diseased skin.
s), hoe (paddle
s), ihe (short spear
s), pololu (long spears), ōō (digging stick
s), ie kūkū (square kapa
beaters), and papa olonā (Touchardia latifolia
scrapers). Koaia leaves were used to cover hale lau koaie (shelters and permanent sheds).
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 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 pea
Pea
A pea is most commonly the small spherical seed or the seed-pod of the pod fruit Pisum sativum. Each pod contains several peas. Peapods are botanically a fruit, since they contain seeds developed from the ovary of a flower. However, peas are considered to be a vegetable in cooking...
family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
, Fabaceae
Fabaceae
The Fabaceae or Leguminosae, commonly known as the legume, pea, or bean family, is a large and economically important family of flowering plants. The group is the third largest land plant family, behind only the Orchidaceae and Asteraceae, with 730 genera and over 19,400 species...
, 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 is closely related to koa (A. koa), and is sometimes considered to be the same species. Koaia is usually distinguished by growing as a short (rarely more than 5 m (16.4 ft)), broad, gnarled tree; having the seed
Seed
A seed is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant...
s longitudinally arranged in the pod; shorter, straighter phyllodes; and much denser wood. A population on the northern coast of Kauai
Kauai
Kauai or Kauai, known as Tauai in the ancient Kaua'i dialect, is geologically the oldest of the main Hawaiian Islands. With an area of , it is the fourth largest of the main islands in the Hawaiian archipelago, and the 21st largest island in the United States. Known also as the "Garden Isle",...
may be intermediate, but the relationships have not been worked out. Koaia wood is claimed to be very different from that of koa, and this may be the best character to separate them.
Koaia is highly adapted to dry habitats, and is capable of forming dense forests in areas with very little rainfall. It was formerly found widely in dry forests
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...
on all of the main islands. Associated plants include uluhe (Dicranopteris linearis
Dicranopteris linearis
Dicranopteris linearis is a common species of fern known by many common names, including Old World forked fern and uluhe . It is one of the most widely distributed ferns of the wet Old World tropics and adjacent regions, including Polynesia and the Pacific...
), hala (Pandanus tectorius
Pandanus tectorius
Pandanus tectorius is a species of Pandanus that is native to Malesia, eastern Australia, and the Pacific Islands. Common names include Thatch Screwpine, Hala , Bacua , and Vacquois ....
), kookoolau (Bidens
Bidens
Bidens is a genus of flowering plants in the family Asteraceae. It contains about 200 species. The common names beggarticks, black jack, bur-marigolds, stickseeds, tickseeds and tickseed sunflowers refer to the achene burrs on the seeds of this genus, most of which are barbed...
spp.), kokio (Hibiscus kokio
Hawaiian hibiscus
Hawaiian hibiscus are the seven known species of hibiscus regarded as native to Hawaii. Although tourists regularly associate the hibiscus flower with their experiences visiting the US state of Hawaii, and the plant family Malvaceae includes a relatively large number of species that are native to...
), nehe (Lipochaeta
Lipochaeta
Lipochaeta is a genus of flowering plants in the daisy family, Asteraceae.-Selected species:*Lipochaeta connata DC. – Nehe *Lipochaeta degeneri Sherff – Molokai Nehe...
spp.), hala pepe (Pleomele
Pleomele (genus)
Pleomele is a genus of flowering plants, sometimes placed in the genus Dracaena. In the APG III classification system, both genera are placed in the family Asparagaceae, subfamily Nolinoideae...
spp.), and ōhia lehua (Metrosideros polymorpha
Metrosideros polymorpha
The ōhia lehua is a species of flowering evergreen tree in the myrtle family, Myrtaceae, that is endemic to the six largest islands of Hawaii. It is a highly variable tree, being tall in favorable situations, and much smaller when growing in boggy soils or on basalt...
). Like many legumes, koaia is able to fix nitrogen
Nitrogen fixation
Nitrogen fixation is the natural process, either biological or abiotic, by which nitrogen in the atmosphere is converted into ammonia . This process is essential for life because fixed nitrogen is required to biosynthesize the basic building blocks of life, e.g., nucleotides for DNA and RNA and...
. However, it has been devastated by cattle
Cattle
Cattle are the most common type of large domesticated ungulates. They are a prominent modern member of the subfamily Bovinae, are the most widespread species of the genus Bos, and are most commonly classified collectively as Bos primigenius...
and other ungulate
Ungulate
Ungulates are several groups of mammals, most of which use the tips of their toes, usually hoofed, to sustain their whole body weight while moving. They make up several orders of mammals, of which six to eight survive...
s and is now rare. It can be seen on ranch land in North Kohala
Kohala, Hawaii
thumb|right|300px|The districts of the [[Hawaii |Big Island]]. From Northernmost, clockwise; Kohala , [[Hamakua|Hāmākua]], [[Hilo, Hawaii|Hilo]], [[Puna, Hawaii|Puna]], [[Kau, Hawaii|Kaū]], [[Kona District, Hawaii|Kona]]...
, and at a small fenced exclosure outside of Waimea known as the koaia sanctuary. Koaia is one of the species being used to revegetate the island of Kahoolawe
Kahoolawe
Kahoolawe is the smallest of the eight main volcanic islands in the Hawaiian Islands. Kahoolawe is located about seven miles southwest of Maui and also southeast of Lanai, and it is long by wide, with a total land area of . The highest point on Kahoolawe is the crater of Lua Makika at the...
, which lost most of its plant life to overgrazing
Overgrazing
Overgrazing occurs when plants are exposed to intensive grazing for extended periods of time, or without sufficient recovery periods. It can be caused by either livestock in poorly managed agricultural applications, or by overpopulations of native or non-native wild animals.Overgrazing reduces the...
and ordnance testing.
Medicinal
Native HawaiiansNative 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...
ground koaia leaves and bark with auaukoi (Senna
Senna (genus)
Senna , the sennas, is a large genus of flowering plants in the family Fabaceae, subfamily Caesalpinioideae. This diverse genus is native throughout the tropics, with a small number of species reaching into temperate regions. The number of species is usually estimated to be about 260, but some...
occidentalis
Senna occidentalis
Senna occidentalis is a pantropical plant species.Vernacular names include : ʻauʻaukoʻi in Hawaii, coffee senna, coffeeweed, Mogdad coffee, negro-coffee, senna coffee, Stephanie coffee, stinkingweed or styptic weed....
) and kikānia pipili (Desmodium
Desmodium
Desmodium is a genus in the flowering plant family Fabaceae, sometimes called tick-trefoil, tick clover or beggar lice. There are dozens of species and the delimitation of the genus has shifted much over time....
sandwicense) stalks. The mixture was then hydrated and used in a steam bath to treat diseased skin.
Non-medicinal
The wood of koaia is harder and more dense than that of koa. It was used to make laau melomelo (fishing lureFishing lure
A fishing lure is an object attached to the end of a fishing line which is designed to resemble and move like the prey of a fish. The purpose of the lure is to use movement, vibration, and colour to catch the fish's attention so it bites the hook...
s), hoe (paddle
Paddle
A paddle is a tool used for pushing against liquids, either as a form of propulsion in a boat or as an implement for mixing.-Materials and designs:...
s), ihe (short 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), pololu (long spears), 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), ie kūkū (square 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), and papa olonā (Touchardia latifolia
Touchardia latifolia
Touchardia latifolia, commonly known as Olonā in Hawaiian, is a species of flowering shrub in the nettle family, Urticaceae. T. latifolia is endemic to Hawaii and inhabits mesic valleys and wet forests at elevations of . Typical to many Hawaiian plants, the olonā does not have any stinging needles...
scrapers). Koaia leaves were used to cover hale lau koaie (shelters and permanent sheds).
External links
- Photos of Acacia koaia at Hawaiian Ecosystems at Risk Project (HEAR)