Salvinia molesta

Other workers have examined the use of insects to consume troublesome weeds. Again there are problems associated with the selection of an insect that is specific to the weed and has no other disadvantages such as the sensitivity of some people. Such systems are unlikely to become widely used in agriculture but do find small niche markets, especially with the home gardener. Workers in South Africa have evaluated several insects for the control of the invasive weed Lantana camara and the aquatic fern Salvinia molesta with encouraging results.9 The grass carp has also been recommended for control of a number of submerged aquatic weeds. 

Pandey DK (1994) Inhibition of Salvinia (Salvinia molesta Mitched) by parthenium Partheniwn hysterophorus L.). II. Relative effect of flower, leaf, stem, and root residue on salvinia and pmldy. J Chem Ecol 20 3123-3131... 

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