About Metrosideros collina (Forst.) A.Gray
Metrosideros collina (Forst.) A.Gray is a species of flowering plant in the myrtle family, Myrtaceae, that grows as either a tree or a shrub. It is native to French Polynesia, the Cook Islands, and the Pitcairn Islands. In the Society Islands, this species is a common canopy tree in montane rain forests located above 300 meters elevation, in cloud forests between 400 and 1000 meters elevation, and on exposed ridges. In the Marquesas Islands, it is common in drier, more exposed montane forests and in cloud forests; it grows in shrub form in windswept mountaintop shrublands. On Rarotonga, part of the Cook Islands, Metrosideros collina is the dominant tree in cloud forests that grow on the island’s cloud-shrouded peaks and ridges above 400 meters elevation. This species and its associated trees, which include Pterophylla samoensis, Elaeocarpus floridanus, and Pittosporum rarotongense, form a low forest canopy that averages eight meters tall. In wetter areas and at higher elevations, Ascarina diffusa is often co-dominant or the dominant canopy species. Metrosideros collina can also be found in lower-elevation rainforests that are dominated by Homalium acuminatum. It is a common canopy tree in higher-elevation interior forests on Pitcairn Island, where it grows alongside the trees Homalium mouo, Ficus prolixa, Pandanus tectorius, and Thespesia populnea.
