Miconia calvescens

It forms dense monotypic stands which have progressively overwhelmed the native forests, this plant pest is a direct threat to the rich Tahitian indigenous flora.Miconia calvescens DC. (Melastomataceae), first introduced to Tahiti (French Polynesia, South Pacific Ocean) in 1937 as an ornamental plant, now covers over two-thirds of the island. Between 40 and 50 species of the 107 species endemic to Tahiti are thought to be on the verge of extinction.

Miconia calvescens has the potential to accelerate surface erosion in stands where it invades by (i) reducing under‐canopy light levels, thereby reducing the establishment of ground cover vegetation, and (ii) producing highly erosive throughfall drops on large leaves in a single‐layer canopy. The large, dark leaves of miconia reduce light levels beneath the canopy, thereby inhibiting germination and growth of understory plant species that would typically dissipate the erosive energy of throughfall drops (Meyer, 1994, 2004). Its litter decomposes more rapidly than that of native species (Allison and Vitousek, 2004), exposing the soil surface to the direct impact of throughfall drops.

It forms dense monotypic stands which have progressively overwhelmed the native forests, this plant pest is a direct threat to the rich Tahitian indigenous flora.Miconia calvescens DC. (Melastomataceae), first introduced to Tahiti (French Polynesia, South Pacific Ocean) in 1937 as an ornamental plant, now covers over two-thirds of the island. Between 40 and 50 species of the 107 species endemic to Tahiti are thought to be on the verge of extinction. Miconia calvescens has already attained dominance over most of the island of Tahiti. Dense, monotypic stands of this species occupy mesic and wet environments (mean annual rainfall >2000 mm) at 10-1300 m elevation. It not only occupies roadsides, forest edges, and abandoned pastures, but also has invaded primary native forests.