PR Notice 87-1, released by the Environmental Protection Agency, now requires pesticide manufacturers to include specific statements on the label regarding application through irrigation systems. The statements are required on all pesticides shipped after April 30, 1988. If the material is not registered for chemigation, the following statement should be found on the label: "Do not apply this product through any type of irrigation system."
For materials that are registered for chemigation, the following generic label statements are required:
a) Apply this product only through one or more of the following types of irrigation systems: sprinkler (including center pivot) lateral move, end tow, side roll, traveler, big gun, solid set, or hand move; flood (basin); furrow; border or drip (trickle) irrigation systems(s). Do not apply this product through any other type of irrigation system.
b) Crop injury, lack of effectiveness, or illegal pesticide residues in the crop can result from nonuniform distribution of treated water.
c) If you have questions about calibration, you should contact state extension service specialists, equipment manufacturers or other experts.
d) Do not connect an irrigation system (including greenhouse systems) used for pesticide application to a public water system unless the label-prescribed safety devices for public water systems are in place.
e) A person knowledgeable of the chemigation system and responsible for its operation, or under the supervision of the responsible person, shall shut the system down and make necessary adjustments should the need arise.
In addition to the generic label statement, the label will also contain specific label statements depending on the type of irrigation system.
Further requirements for materials intended for chemigation include posting requirements for toxicity category I, and nonspecific label statements, which are recommendations for mixing, agitation, and guidelines for the application of the pesticide with regard to duration of the water application.
It is important to note that these are only guidelines and the requirements may vary by county, state or federal regulations. For further information, or to ensure that your system meets the EPA requirements, contact your county agricultural commissioner's office.