It includes the central and eastern Caroline Islands in the Federated States of Micronesia.
[1] The Chuuk islands are surrounded by almost circular barrier reef more than 60 km across at its widest point, which encloses a lagoon and 69 low islets composed of coral sand.
The center of the island is a tableland with 11 separate peaks, the tallest of which reaches 734 meters elevation.
[1] Kosrae lies 550 km to southeast of Pohnpei towards the eastern end of the Carolines.
It is a deeply dissected volcanic island with several steep high peaks, the highest of which reaches 629 meters elevation.
[1] The natural vegetation of the islands was mostly tropical rain forest, with smaller areas of savanna and scrub, and mangroves along the shore.
The islands are sufficiently close to Southeast Asia's diverse forests to allow plants to disperse, while the islands' age and relative isolation allowed plants to evolve into distinct species.
Other montane forest trees include species of Glochidion, Myrsine, Elaeocarpus, Syzygium, Psychotria, Timonius, Gynotroches, and Astronidium, and the palms Ptychosperma and Metroxylon.
Lianas of Ipomoea, Merremia, Freycinetia, Hypserpa, and Pachygone are abundant, and there are many terrestrial and epiphytic ferns.
The principal trees of Kosrae's montane forests include species of Horsfieldia, Neuburgia, Psychotria, Syzgium, Campnosperma, Macaranga, Dendrocnide, Boehmeria, and Ficus, tree ferns (Sphaeropteris sp.
The understory is composed of lush mosses, herbaceous hepatics (members of the buttercup family, and the ferns Marattia fraxinea and Pteris spinescens There are many epiphytes, including Elaphoglossum carolinense, Hymenophyllum polyanthos, Lindsaea rigida, and the endemic Peperomia kusaiensis.
[1] The mottled munia (Lonchura hunsteini) was introduced to Pohnpei from New Ireland in the 1920s, and is abundant on the north and east of the island.
Early settlers brought and cultivated coconut, breadfruit, taro, bananas, and sugarcane in the lowlands.
It requires fertile organic soil, and montane forests are being cleared to expand its cultivation.