First Attempt at and Early Results on the Biological Control of Pistia stratiotes L. in South Africa

Abstract

Although Pistia stratiotes L. (water lettuce) is not an important weed in the Republic of South Africa, the host-specific weevil Neohydronomus pulchellus Hustache was imported for the biological control of this weed. The weevil was released onto a dense infestation of P. stratiotes of several years standing on a pan in the Pafuri area in December 1985. By September 1986 the weevils had already destroyed most of the weed and in October 1986 the weed was under biological control at this site.