Clidemia hirta (L.) D.Don

Mayotte : Clidemia hirta flowers and fruits all year round.

Comoros: Clidemia hirta is a newly introduced species, probably in the 1970s. It spreads very rapidly both in open and closed areas, in dry or humid areas. It is able to colonize large areas very quickly. It was observed in all regions of the island of Grande Comore up to 1800 m altitude.
French Guiana: It is occasionally found in orchards or pineapple plantations in more or less recent forest slashed areas.
Madagascar: Very common species on the wet eastern side of the island. This species, disseminated by birds, infests the edges of fields and canals, uncultivated land and sometimes old plots of "tavy" (shifting cultivation).
Mauritius: Weed very common in the humid part of the island, in the sugar cane fields, uncultivated land and pastures for deer.
Mayotte: Clidemia hirta is an exotic species and very widely naturalized as an invader in mesophilic and hygrophilic regions in natural or degraded environment. It is found along roads, in undergrowth, around wetlands, in crops, gardens, wastelands, pastures, villages and ditches.
Reunion: This species, very shade tolerant emerged in the 1970s in the rainforests of low altitude of Southeast Reunion and in the vanilla plantations at the same time with Pycnonotus jocosus (Bulbul), which is the main disseminator. It then spreaded largely throughout the island in culture as well as in natural environment. Indeed, C. hirta is commonly encountered in areas ranging from St. Joseph to St. Suzanne and rarely between Saint-Joseph and Saint-Pierre.
Seychelles: Present in unoccupied land and forest land, it is rarely abundant.
West Indies: Clidemia hirta is an indigenous species. This species contributes to plant formations (woods and coppices) in mesophilic and hygrophilic environments. In agricultural areas, it often occupies the edges of fields (fences, hedges, coppices...) and settles permanently in perennial crops.

Local harmfulness
 
Comoros: Clidemia hirta is a very invasive species present in the abandoned waste land and plantations in forest areas (banana, cassava, vanilla). Because of its fairly deep roots, it is difficult to remove.
French Guiana: A moderately frequent species and generally not very abundant in fruit  and pineapple plots.
Madagascar: A weed common and abundant in the uncultivated lands and very inconvenient for development with the manual means (such as Lantana camara). Its frequency and abundance in annual crops are relatively low.
Mauritius: A weed with low to medium harmfulness, except when present in large numbers in the sugar cane fields.
Mayotte : Clidemia hirta is a weed that is globally not very frequent, present in 4% of cultivated plots. It is found more particularly in ylang plantations, and also in pineapple crops.
Reunion: C. hirta is present in 10% of surveys with an average cover of 7-15% of the surface. It is present in 10% of surveys in sugarcane cultivation and 20% in pineapple, it does not present any particular problem when grassing is well managed. Conversely, one can occasionally observe plots where the cover reaches 30-50%, due to poor management of weed, due to a lack of effective herbicides products and great difficulty to fight manually. In mégatherme forest, it can completely occupy the undergrowth, developing dense thickets.
Seychelles: invasive plant in the forest.
West Indies: Clidemia hirta is almost absent from cane, food and vegetable crops, it is frequent in banana plantations and orchards. It tolerates shade well and often settles at the foot of trees and at the edge of plots. It is not very harmful but is resistant to certain herbicides. It becomes very troublesome when it reaches a high level of abundance. Under these conditions, it forms thickets that make plots difficult to access.

Global control

Clidemia hirta is very difficult to uproot because of its deep taproot.
 
Local control

Reunion: see the website of CaroCanne (The online magazine of sugar cane workers in Réunion);
Mauritius: See MSIRI Recommendation Sheet No 172 - Chemical Control of Clidemia hirta (Watook) in Sugarcane fields (click here)
West Indies: Clidemia hirta is resistant to certain herbicides and tolerant to mechanical slashing techniques (brush cutting), its management requires the implementation of mechanical or manual techniques allowing a complete removal of the plants.

Herbarium pictures ReCOLNAT: https://explore.recolnat.org/search/botanique/simplequery=Clidemia%2520hirta