ABSTRACT
Eurasian watermilfoil (Myriophyllum spicatum) has been established for several decades in Florida. Eurasian watermilfoil is a submersed vascular aquatic plant that produces a mat of vegetation several meters thick and tends to dominate the water surface where it grows. Effective control of Eurasian watermilfoil by herbicide use has been of great value. A high degree of susceptibility to the phenoxy herbicides has been demonstrated. The conventional method of applying liquid formulations of herbicides for submersed aquatic weed control is to apply a phytotoxic herbicide concentration in the entire volume of water. Controlled release of a herbicide from a carrier may also prevent regrowth that emerges from propagating structures buried in the bottom muds. Polyvinyl chloride (PVC) was evaluated as a plastic carrier by preparing herbicide-PVC formulations from a premixed plastisol. The injury rating decreased at later observation periods indicating that regrowth was occurring.
