Shrubs

Dricanopteris heath is the main form of degraded Metrosideros forest on the plateaux and peaks of the Society Islands between altitudes of 200 and 400 m. Such formations have suffered from repeated fires, which have reduced them to a herbaceous formation of ferns, in which Dicranopteris linearis is predominant in dense thickets growing to a height of 2 m. Dicranopteris heath is found in similar environments in the Tubuai Islands, but is disappearing through overgrazing. In the Marquesas Islands, it represents a degraded form of mesophile Sapindus forest.

Miscanthus-Psidium savannah, the degraded form of low- and medium-altitude mesophile forest, is found in the driest parts of the Society Islands. Miscanthus floridulus and Psidium guyava grow together at low altitudes. In the Tubuai Islands, pure stands of Miscanthus floridulus cover large areas up to 250 m. This formation is found on steep cliffs in the Marquesas Islands.

Leucaena leucocephala brushland forms pure stands below 200 m in some of the Society Islands. This formation reaches a maximum height of 6 m, and is a degraded form of low-altitude mesophile formations. It also covers relatively large areas in the Marquesas Islands.

Malvaceae-Sterculaceae brushland forms a belt around Nuku Hiva (Marquesas Islands) up to an altitude of 300 m and is the main degraded form of forests at these altitudes. The brushland is 2 m high, with Sidastrum paniculatum and Waltheria tomentosa as the dominant species.

Peaks above 900 m in the Society Islands have low forests (3 m) with a herbaceous association of Vaccinium cereum and Astelia nadeaudii. This is a transitional form between rainforest and peak brushland.

Brushland on peaks above 1 500 m (in the Society and Marquesas Islands) consists of small trees (under 1 m) stunted by the combined effects of wind and low temperatures. The formation is open, with a high degree of endemism, and Vaccinium, Metrosideros spp., etc., are found here.

last updated: Tuesday, January 13, 2004