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Abstract In recent years, many researchers have put much effort into developing new chemicals for use as insecticide and herbicides. The use of herbicides to control and inhibit undesirable weed growth is well known and accepted. As a result, there is widespread use in agricultural, industrial, and domestic fields. Roadsides, embankments, railway rights¬of way and other earth surfaces are often subjected to treatment with toxic chemicals, organic and inorganic. Numerous compounds with widely variant functionalities are effective to a greater or lesser degree in inhibiting or destroying the growth of undesirable vegetation. One of the most widely used techniques in chemical application is to accomplish the control by spraying the active chemical upon the area within which the disease or the weed is expected. In some instances, expected areas of weed growth are sprayed in early spring or late fall to prevent an appearance of noxious plants or at least to severely weaken their growth patterns. Certain problems arise in connection with such chemical applicatipns. First, and foremost, is a problem of misting or fogging which generally begins to occur at a spray pressure of 15 psi and worsens as spray pressures are increased. The chemical spray tends to drift and valuable crops that are downwind can be destroyed or damaged to varying degrees. In some instances, due to the extreme toxicity of certain chemicals, even valuable animal life such as livestock can be injured. The problem of drift has become more widespread in recent years, due to the more extensive use of herbicides and to the application of |