Weed Problems and Weed Control in the Commonwealth Caribbean

Abstract

Abstract The effect of weeds on crops is discussed, with particular reference to the Commonwealth Caribbean. The most serious weeds in the region are Cyperus rotundas, Cynodon dactylon, Commelina spp., Parthenium hysterophorus, Portulaca oleracea, Cleome spp. and Amaranthus spp. Serious weeds include Eleusine indica, Echinochloa colonum, Euphorbia spp., Brachiaria mutica, Paspalum conjugatum, Sporobolus indicus and Ipomoea tiliaceae. Brief notes are given for these species and also for the locally serious weeds, Rottboellia exaltata, Digitaria sanguinalis, Mimosa pudica, Scleria reflexa, Cenchrus echinatus. Control measures include macheting, hand weeding, flooding, mulching and short-term fallows. Herbicides are used especially by larger vegetable growers and in sugarcane and citrus groves. Paraquat is the most widely used. Other chemicals used in specific situations are listed. Knapsack sprayers are the commonest application method but granular and c.d.a. application is likely to increase. Weed control research in the Commonwealth Caribbean is also briefly reviewed.