The dense mats of S. molesta clog waterways and irrigation canals, block passage, obstruct irrigation pumps, prevent light from reaching aquatic plants, reduce the oxygen content of the water and seriously degrade the quality of the water. The leaf surface is covered with minute stalks bearing 3 or 4 hairs joined at the tips forming cage-like structures that resemble inverted kitchen whisks. This fern is grown in garden ponds and aquaria and is known to be in cultivation in the Islands. It escapes from cultivation and invades aquatic fresh water bodies where is grows aggressively, rapidly becoming a serious pest. It is listed on the Federal Noxious Weed list .
Every effort needs to be made to control the growth and spread of Salvinia molesta.