Broadleaved

Open forests on high islands occur as three main types of association, depending on the island in question:

    Casuarina forest is found on hilltops and crests below 200 m on Moorea and Tahiti (Society Islands) and in the Marquesas Islands. This is an open pure forest of Casuarina equisetifolia, reaching a height of 8 to 12 m. Patches of Lantana camara and Dicranopteris are also found, but it has practically no herbaceous layer;

    Dodonaea-Xylosma forest is a low, open formation found on the driest crests in the Tubuai Islands; it is made up of Dodonaea viscosa, Xylosma suaveolens and Casuarina equisetifolia. It is often degraded through human activities, and in such cases some naturalized species, such as Psidium guyava or Lantana camara, appear;

    Metrosideros-Weinmannia forest is found on the driest hills and slopes in the Marquesas Islands. It is a low (3 m), open formation, made up of Metrosideros collina, Weinmannia parviflora and other endemic woody species. The herbaceous layer is composed of ferns.

Open forests on atolls were originally composed mostly of Pisonia grandis, with an undergrowth of ferns, grasses, and some bushes and shrubs, but such formations have been almost completely destroyed on the atolls to make way for coconut plantations. However, a few remnants are still found on some motus. Pisonia grandis can grow to over 20 m and is generally found in association with Guettarda speciosa and Pipturus argenteus. The shrub layer contains a small number of species (Morinda citrifolia or Euphorbia atoto), and the herbaceous layer is varied.

last updated: Wednesday, October 6, 2004