ABSTRACT
Aquatic macrophyte problems have become common in the reservoirs and inland waterways of the US Pond and lakes — Granular formulations may prevent occurrence of high concentrations of certain herbicides in water by confining portions of the chemicals at the soil surface. The use of phenoxy-type herbicides in aquatic situations is almost entirely limited to derivatives of 2,4-dichlorophenoxy acetic acid (2,4-D). Most organic herbicides used for control of aquatic weeds are resistant to chemical attack. Degradation of 2,4-dichlorophenol, sodium salt of 2,4-D, and butyl and isopropyl esters of 2,4-D were relatively rapid and pH dependent. No harmful response to the herbicide was observed in zooplankton, phytoplankton, benthic macroinvertebrates, or fish. The use of herbicides in water assumes that in the normal process of degradation certain amounts may deposit on the bottom muds. Potable water supplies frequently become infested with algal blooms which produce objectionable flavors and odors.
