Three rinses are the key to proper sprayer maintenance and vibrant crops.
When it comes to your crops and sprayers, very small amounts of chemical residues can cause big problems.
“Insurance will not pay for damages you caused to your crops,” Fred Whitford of Purdue Agriculture told farmers at Corn College 2015. This puts proper sprayer maintenance in perspective to ensure a clean pass in the field and avoid unnecessary damage to your crops.
Although farmers will admit cleaning their sprayer is important to good crop management, they also say they don’t always have the time to go through the whole cleaning process.
You might want to think about making the time. If you don’t take proper care of your sprayer, you could be looking at a total yield loss and not have a leg to stand on. Skeptical? Just look at the difference between these fields.
The key to thoroughly cleaning a sprayer and protecting your crops from contamination is not one, not two, but three, and sometimes even four rinses, Whitford said. Here’s the approach he recommends.
Before you actually do the first rinse, it’s important to empty the booms, tank and hoses. The tank and hoses often have residual chemicals that well up in low places that can be missed. Both are also normally plastic and can pull in chemicals if they sit too long, making it harder to prevent contamination.
Once you’ve emptied the equipment, do the first rinse in the field. Even though you may think your sprayer is empty, there still can be a fair amount of chemicals left in the tank, and you don’t want any of those to seep into groundwater.
Before you start a second rinse, remove and thoroughly clean all the screens, according to Whitford. A common mistake in cleaning the screens is just flushing them out. This may remove large chunks, but it won’t remove any caked-on substances, so you need to use a brush and soap to properly clean the screens.
What’s another commonly neglected area of the sprayer? End caps. These are the difficult-to-remove dead spaces at the ends of the booms. Chemicals circulate here and build up, creating a toothpaste-like substance to continue to contaminate the system.
“If the screens [and end caps] are not cleaned, you will continue to see problems,” Whitford said.
Once that’s done, you can replace your screens and do your second rinse, either in the field or on a gravel road. Once the second rinse is finished, you can replace the end caps and move on to the next rinse.
Before you do the third rinse, you should add a tank cleaner—but keep in mind what it can and can’t do.
“These cleaners can’t do what you think they can do in 15 minutes,” said Whiford, explaining that such cleaners are needed to only help neutralize remaining chemicals. As for the best tank cleaner, Whitford recommended Roundup, because it has surfactants to pull out chemicals stuck in the plastic parts.
The third rinse can now be done followed a fourth rinse, if you choose. Many farmers choose to do a fourth rinse, just in case any tank cleaner was missed in the last flush.
Spray the Outside
One final step often missed is power-washing the outside of the sprayer. There can be dried herbicide residue on the outside of the sprayer, which can mix with other chemicals and contaminate the field.
It’s a lot of work, Whitford said, but it’s worth the extra time and effort to not lose yields. He closed by asking farmers what grade, from A to F, they would give their sprayer cleaning and what they would do to improve it.
“If you don’t give yourself an A, find a way to do something better,” he told Corn College attendees. After all, you don’t want to accidentally kill your crops by neglecting to rinse out your sprayers.
Fred Whitford’s Sprayer Checklist
Want to make sure you get an A? Follow this checklist provided by Whitford.
- Empty boom every night.
- First rinse sprayed in field.
- Remove, clean and replace screens.
- Remove and clean all end caps.
- Second rinse with water and replace end caps.
- Add and hold tank cleaner.
- Third rinse and flush.
- Fourth rinse, if necessary.
- Rinse outside of sprayer.