Cut Crop Injury By Cleaning Sprayer Properly

 A clean sprayer is essential to prevent damage from herbicide contamination to susceptible crops.  Rinsing with water is not adequate to remove all herbicides. Some herbicides have remained tightly adsorbed in sprayers through water rinsing and even through several tank-loads of other herbicides. Then, when a tank-load of solution, including an oil adjuvant or nitrogen solution, was put in the sprayer, the herbicide was desorbed, moved into the spray solution, and damaged susceptible crops. Highly active herbicides that have been difficult to wash from sprayers and have caused crop injury include dicamba, Pursuit, Raptor and sulfonylurea herbicides.

Proper sprayer cleanout procedures are given on many herbicide labels and the procedure on the label should be followed for specific herbicides. The following procedure illustrating a thorough sprayer cleanup procedure is effective for most herbicides:

Step 1. Drain tank and thoroughly rinse interior surfaces of tank with clean water. Spray rinse water through the spray boom. Sufficient rinse water should be used for 5 minutes or more of spraying through the boom.

Step 2. Fill the sprayer tank with clean water and add a cleaning solution (many labels provide recommended cleaning solutions). Fill the boom, hoses, and nozzles and allow the agitator to operate for 15 minutes.

Step 3. Allow the sprayer to sit for 8 hours while full of cleaning solution so the herbicide can be fully desorbed from the residues inside the sprayer.

Step 4. Spray the cleaning solution through the booms.

Step 5. Clean nozzles, screens, and filters. Rinse the sprayer to remove cleaning solution and spray rinsate through the booms.

Common types of cleaning solutions are chlorine bleach, ammonia, and commercially formulated tank cleaners. Chlorine lowers the pH of the solution, which speeds the degradation of some herbicides. Ammonia increases the pH of the solution, which increases the solubility of some herbicides. Commercially formulated tank cleaners generally raise pH and act as detergents to remove herbicides. Read herbicide label for recommended tank cleaning solutions and procedures. Never mix chlorine bleach and ammonia, as a dangerous and irritating gas will be released.

Sprayers should be cleaned as soon as possible after use to prevent the deposit of dried spray residues. A sprayer should not remain empty overnight without cleaning; fill the tank with water to prevent dried spray deposits from forming.

Source: NDSU

Sprayer Cleaning Solutions For Herbicides

 Ammonia + water: Accent, Ally, Amber, Assure II, Basis, Basis Gold, Beacon, dicamba, Exceed, Expert, Finesse, FirstRate, Glean, Peak, Permit, Harmony GT, Python, Resolve, Stinger.

Kerosene or diesel fuel followed by ammonia + water: 2,4-D ester

Ammonia or commercial tank cleaner + water: Action, Basagran, Bladex, Buctril + Atra, bromoxynil, Callisto, Classic, Cobra, Contour, Dual/II/Magnum, Flexstar, Fusilade DX, Fusion, Gauntlet, Gramoxone, Harness, Harmony Extra, Hornet, Lasso, Lightning, Moxy, Moxynil, Passport, Prowl, Pursuit, Pursuit, Plus, Reflex, Resource, Scepter, Select, Squadron, Status, Steel, Surpass, Treflan, trifluralin, and Ultra Blazer.

Water: Command and glyphosate.

Detergent + water: Atrazine and Sencor.

Commercial tank cleaner + water: Liberty, Marksman, Optill, Shotgun, and Touchdown

Detergent or commercial tank cleaner + water: Turbo

Ammonia, commercial tank cleaner, or detergent + water: Poast.

Baking soda (1 to 2 lb/100 gal water): Engame nf