Miconia: Miconia calvescens

One of the Pacific’s most menacing weeds

It would be easy to describe Miconia (Miconia calvescens) as the scariest weed in the Pacific islands. Imagine an herbaceous looking plant that can grows purplish leaves that are nearly 6 feet long. It can grow into a small tree 50 feet tall. In wet forests it grows quickly and can take over a forest, chocking out the other plants. Now imagine a giant hillside that Miconia has taken over. The shallow roots of Miconia don’t stabilize the soil though, eventually, this hillside could collapse in a giant mudslide. It’s a story all too familiar to Tahitians and something Hawaii wants to stop before it gets to that stage.

Distribution

Miconia is native to Central and South America but has been introduced to various othe places, including many of the Pacific Islands. It was introduced to the Islands of Hawaii in 1960. It was reported wild in in 1982.

While this enormous melastomacous plant is fairly restricted in range on Maui and the Big Island, it is top on the list of weeds to get rid of. A few plants have been found on Oahu and Kauai and a great deal of effort is used to exterminate it when they’re found.

General Description

Miconia is easily recognized. Like most other melastomacous plants, it has 3 prominent veins that run longitudinally from the stem leaf to the leaf tip. The leaf is hairy and the undersides are reddish-purple. The leaves are opposite. 

Other Video Describing the Control of Miconia