Poa mannii is a rare species of grass

Grass

Grasses, or more technically graminoids, are monocotyledonous, usually herbaceous plants with narrow leaves growing from the base. They include the "true grasses", of the Poaceae family, as well as the sedges and the rushes . The true grasses include cereals, bamboo and the grasses of lawns ...

 known by the common names Mann's bluegrass and Olokele Gulch bluegrass. It 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...

, where it is limited to the island 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",...

. It is threatened by the loss and modification of its habitat. It 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.

There are three species of Poa

Poa

Poa is a genus of about 500 species of grasses, native to the temperate regions of both hemispheres. Common names include meadow-grass , bluegrass , tussock , and speargrass. "Poa" is Greek for fodder...

native to Hawaii, and they are all endemic to Kauai. There are at least 13 populations of this species, totalling about 100 individuals. These populations are found on steep slopes and dripping wet cliffs in forests dominated by 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...

and Acacia koa. The fact that it is limited to steep, inaccessible habitat suggests that like many other Kauaian plants, this grass has been eliminated from all other habitat types by feral goat

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...

s, one of the major threats to the species. Other plants in the habitat include ahinahina (Artemisia australis), kookoolau (Bidens sandwicensis), iliau

Wilkesia gymnoxiphium

Wilkesia gymnoxiphium , is a species of flowering plant in the sunflower family, Asteraceae, that is endemic to the island of Kauai in Hawaii...

 (Wilkesia gymnoxiphium), emoloa (Eragrostis variabilis), haiwale (Crytandra wawrae), heau

Exocarpos luteolus

Exocarpos luteolus is a rare species of flowering plant in the sandalwood family known by the common name heau. It is endemic to Hawaii, where it is known only from the island of Kauai. There are eight populations remaining, for a total global population of only 39 individuals...

 (Exocarpos luteolus), kamakahala

Labordia helleri

Labordia helleri is a rare species of flowering plant in the Loganiaceae family. It is endemic to Hawaii, where it is found only on Kauai. It is a federally listed endangered species of the United States...

 (Labordia helleri), kului

Nototrichium

Nototrichium is a genus of flowering plants in the pigweed family, Amaranthaceae. All members of the genus are endemic to the Hawaiian Islands. They are known in Hawaiian as kuluī.-Species:*Nototrichium divaricatum Lorence...

 (Nototrichium sp.), manono (Hedyotis terminalis), mokihana (Melicope anisata), pelea (Melicope barbigera), alaa

Pouteria sandwicensis

Pouteria sandwicensis is a species of flowering tree in the sapodilla family, Sapotaceae, that is endemic to the main islands of Hawaii. Names for this species in the Hawaiian language include Ālaa, Āulu and Ēlaa....

 (Pouteria sandwicensis), lama

Diospyros sandwicensis

Diospyros sandwicensis is a species of flowering tree in the ebony family, Ebenaceae, that is endemic to Hawaii. Its common name, Lama, also means enlightenment in Hawaiian. Lama is a small to medium-sized tree, with a height of and a trunk diameter of . It can be found in dry, coastal mesic,...

 (Diospyros sandwicensis), kopiko

Psychotria mariniana

Psychotria mariniana, or Kōpiko, is a tree endemic to Hawaii. The plant belongs to the Rubiaceae family, subfamily Rubioidae...

 (Psychotria mariniana), Kaua’i wild coffee

Psychotria greenwelliae

Psychotria greenwelliae is a species of plant in the Rubiaceae family. It is endemic to the islands of Kauai and Oahu in Hawaii. It is threatened by habitat loss.-Source:* World Conservation Monitoring Centre 1998. . Downloaded on 23 August 2007....

 (Psychotria greenwelliae), and kokio

Kokia kauaiensis

Kokia kauaiensis, the Kauai Kokio, is a species of flowering plant in the mallow family, Malvaceae, that is endemic to Kauai, Hawaii.It inhabits coastal mesic and mixed mesic forests at elevations of...

 (Kokia kauaiensis).

Besides feral goats, the plant and its habitat are threatened by introduced 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...

of plants, fire, hurricanes, and landslides.