The Hawaiian tropical dry forests are a tropical dry broadleaf forest

ecoregion An ecoregion (ecological region) or ecozone (ecological zone) is an ecologically and geographically defined area that is smaller than a bioregion, which in turn is smaller than a biogeographic realm. Ecoregions cover relatively large areas of ...

in the Hawaiian Islands. They cover an area of on the leeward side of the main islands and the summits of

Niihau Niihau ( Hawaiian: ), anglicized as Niihau ( ), is the westernmost main and seventh largest inhabited island in Hawaii. It is southwest of Kauaʻi across the Kaulakahi Channel. Its area is . Several intermittent playa lakes provide wetland ha ...

and

Kahoolawe Kahoolawe (Hawaiian: ), anglicized as Kahoolawe (), is the smallest of the eight main volcanic islands in the Hawaiian Islands. Kahoolawe is located about southwest of Maui and also southeast of Lānaʻi, and it is long by wide, with a total l ...

. These forests are either seasonal or

sclerophyll Sclerophyll is a type of vegetation that is adapted to long periods of dryness and heat. The plants feature hard leaves, short internodes (the distance between leaves along the stem) and leaf orientation which is parallel or oblique to direct ...

ous. Annual rainfall is less than and may be as low as ; the rainy season lasts from November to March. Dominant tree species include koa (''

Acacia koa ''Acacia koa'' or commonly known as koa is a species of flowering tree in the family Fabaceae. It is endemic to the Hawaiian Islands, where it is the second most common tree. The highest populations are on Hawaii, Maui and Oahu. Name The name ...

''), koaia ('' A. koaia''), akoko (''

Euphorbia ''Euphorbia'' is a very large and diverse genus of flowering plants, commonly called spurge, in the family Euphorbiaceae. "Euphorbia" is sometimes used in ordinary English to collectively refer to all members of Euphorbiaceae (in deference to t ...

'' spp.), 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 ...

''), lonomea ('' Sapindus oahuensis''), māmane (''

Sophora chrysophylla ''Sophora chrysophylla'', known as ''māmane'' in Hawaiian, is a species of flowering plant in the pea and bean family, Fabaceae, that is endemic to Hawaii. It is highly polymorphic, growing as a shrub or tree, and able to reach a height of ...

''), loulu ('' Pritchardia'' spp.), lama (''

Diospyros sandwicensis ''Diospyros sandwicensis'' is a species of flowering tree in the ebony family, Ebenaceae, that is endemic to Hawaii. It belongs to the same genus as both persimmons and ebony. Its common name, ''lama'', also means enlightenment in Hawaiian. ...

''), olopua ('' Nestegis sandwicensis''), wiliwili (''

Erythrina sandwicensis Wiliwili (''Erythrina sandwicensis''), is a species of tree in the pea family, Fabaceae, that is endemic to the Hawaiian Islands. It is the only species of ''Erythrina'' that naturally occurs there. It is typically found in Hawaiian tropical dry ...

''), and iliahi (''

Santalum ''Santalum'' is a genus of woody flowering plants in the Santalaceae family, the best known and commercially valuable of which is the Indian sandalwood tree, '' S. album''. Members of the genus are trees or shrubs. Most are root parasites w ...

'' spp.).

Endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...

plant species in the dry forests include hau heleula (''

Kokia cookei ''Kokia cookei'' is a small, deciduous tree commonly known as the kokio, Molokai treecotton, Cooke's kokio, or Molokai kokio. Distribution This species is only known to have existed in the lowlands of western Molokai island of the Hawaiian Islan ...

''), uhiuhi (''

Caesalpinia kavaiensis ''Mezoneuron kavaiense'' is a rare shrub or small tree in the genus ''Mezoneuron'' (pea family, Fabaceae), that is endemic to Hawaii. Common names include ''Uhiuhi'' ( the Big Island and Kauai), ''Kāwau'' (Maui), and ''Kea'' (Maui). It is thre ...

''), and '' Gouania'' spp. The

palila The palila (''Loxioides bailleui'') is a critically endangered finch-billed species of Hawaiian honeycreeper. It has a golden-yellow head and breast, with a light belly, gray back, and greenish wings and tail. The bird has a close ecological rel ...

(''Loxioides bailleui''), a

Hawaiian honeycreeper Hawaiian honeycreepers are a group of small, passerine birds endemic to Hawaii. They are closely related to the rosefinches in the genus ''Carpodacus'', but many species have evolved features unlike those present in any other finch. Their great ...

, is restricted to this type of habitat.

Prehistoric dry forests

The plant composition of Hawaii's dry forests has changed rather dramatically since the

arrival Arrival(s) or The Arrival(s) may refer to: Film * ''The Arrival'' (1991 film), an American science fiction horror film * ''The Arrival'' (1996 film), an American-Mexican science fiction horror film * ''Arrival'' (film), a 2016 American science ...

of Polynesians, excluding the deliberate introduction of non-native species.

Fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

ized pollen has shown that loulu ('' Pritchardia'' spp.) forests with an understory of Ka palupalu o Kanaloa ('' Kanaloa kahoolawensis'') and aalii (''

Dodonaea viscosa ''Dodonaea viscosa'', also known as the broadleaf hopbush, is a species of flowering plant in the '' Dodonaea'' (hopbush) genus that has a cosmopolitan distribution in tropical, subtropical and warm temperate regions of Africa, the Americas, sout ...

'') existed on the islands' leeward lowlands from at least before 1210 B.C. until 1565 A.D. Populations of loulu and aalii still exist in diminished form, while only two Ka palupalu o Kanaloa specimens have ever been seen in the wild.

Maui

The Auwahi Dryland Forest Restoration Project has produced a substantial forest on the slopes of Haleakala on the island of Maui.

References

External links

* {{cite document , url=http://www.hear.org/naturalareas/auwahi/ethnobotany_of_auwahi.pdf , title=Auwahi: Ethnobotany of a Hawaiian Dryland Forest , first=A. C. , last=Medeiros , author2=C.F. Davenport , author3=C.G. Chimera , publisher=Cooperative National Park Resources Studies Unit,

University of Hawaiʻi at Mānoa The University of Hawaii at Mānoa (University of Hawaii—Mānoa, UH Mānoa, Hawai'i, or simply UH) is a public land-grant research university in Mānoa, a neighborhood in Honolulu, Hawaii. It is the flagship campus of the University of Haw ...

, year=1998

Dry forests The tropical and subtropical dry broadleaf forest is a habitat type defined by the World Wide Fund for Nature and is located at tropical and subtropical latitudes. Though these forests occur in climates that are warm year-round, and may receive ...

Tropical and subtropical dry broadleaf forests Forests of Hawaii Oceanian ecoregions . . . . . .

Prehistoric dry forests

Maui

See also

References

External links