Changing chemicals in a spray tank
If you use liquid herbicides, insecticides, or fungicides then you know how important avoiding cross contamination is. Spraying a tree with a mix that has round-up residuals in it can quickly become a disaster.
Is there any way to be sure a product is never mixed into an unintended batch, by way of residuals, other than having a separate sprayer for each product? What about buying a used spray tank, how can you be sure there isn’t scythe or triplet remaining in the lines before using it for your tree work?
The bottom line is you can’t know if there is some remnants in a spray tank and you can’t afford to take chances, but there is a way to properly clean out a tank. By using a product called “Lesco-sol” or other spray tank cleaners, like neutralize (see more info at bottom of post), you can thoroughly clean out any questionable equipment. The process is an easy 5 steps. Here is how to clean a spray tank.
1- Empty out any remaining product from the tank to be cleaned.
Make sure you spray it out until you are sucking air through your line. *WARNING* do NOT just dump out old products on the ground, either move them to a sprayer still used for that chemical or dump the product into a catch basin designed for chemical removal. Treat your pesticide removal like you treat waste oil.
2- Run clean water through your tank twice, emptying out each time
I know what you are thinking, why not triple rinse ( if you don’t know triple rinsing is the method for cleaning out an empty container that removes all residuals for disposal). I don’t triple rinse because by the end you will have rinsed five times.
3- Add lesco-sol to your tank
One bottle of lesco-sol treats a one hundred gallon spray tank, just read the bottle if in doubt. For a backpack sprayer I just eye out a good pour usually enough to cover the bottom of the sprayer with powder.
4- Add water over the lesco-sol and agitate your tank
Be sure to run the lesco-sol through your tank for a few minutes, recycling water though your spray gun back into the tank will thoroughly clean out the spray lines. This step is important because the cleaning agent is abrasive and will help get any persistent chemicals out.
5- After using lesco-sol rinse out with clean water two more times.
That should do it! You now have a clean spray tank that could go from being used for lawn weeds to spraying junipers for disease or from round-up to nutsedge without fear of spraying an unwanted chemical on your plants. This procedure is especially important any time you buy used spray equipment, even if the seller claims that it was only used for water.
A last note, while I do recommend lescosol because we all know and trust the brand Lesco, there are cheaper options that I have used and they work well. I am posting a link here to one I have used before-