Agricultural spray adjuvant

Agricultural spray adjuvants are used to enhance the effectiveness of pesticides such as herbicides, insecticides, fungicides and other agents that control or eliminate unwanted pests. As with medical adjuvants, agricultural spray adjuvants are not themselves active in controlling or killing pests. Instead, these additives modify some property of the spray solution, which improves the ability of the pesticide to penetrate, target or protect the target organism. Among the typical types of ingredients used are surfactants, emulsifiers, oils and salts. Each of these ingredients, and others, modifies the spray solution itself to improve such properties as spreading, penetration, droplet size or other characteristics.

These additives may be included in a formulation with a pesticide or may be added separately to a tank. When they are included in the pesticide formulations themselves, they are called in-can adjuvants. Agricultural spray adjuvants may also be added separately when the spray solution is being prepared. In this case, the adjuvant is called a tank mix adjuvant. When delivered in-can, adjuvants may be quite effective. However, because of the limited space or limited compatibility in a pesticide formulation, not all necessary adjuvants may be included in-can. Thus, the addition of tank mix adjuvants may be necessary to optimize performance of the pesticide.

Agricultural spray adjuvants do not reduce the amount of pesticide needed below the recommended use rate on a pesticide label. In fact, it is illegal to use a pesticide outside of the instructions on the label, although, FIFRA, the act governing pesticide use, does allow for the use of pesticides at rates below the label, as long as the label does not specifically deny such use. Agricultural spray adjuvants are used to enhance the performance of the legal amount of a pesticide that may be used. These adjuvants give more consistent performance and may make up for underperformance under certain conditions.

In the United States, agricultural tank adjuvants are essentially unregulated except in a few isolated cases. The states of Washington and California require that adjuvants be registered before they can be sold. Other states may or may not regulate adjuvants at some level. There is no federal regulation of tank mix adjuvants.

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Wikipedia