By: Kale Wilson BSA, P. Ag, CCA, Regional Crop Specialist, Swift Current
There are many factors to consider in herbicide applications including application rates, tip calibration, tank mixing and tank clean out. It is import for producers to look at the herbicide label to reduce the risk of injury to crops. When working with your sprayer, it is important to regularly check that your nozzles are all working and applying the correct rates. Calibration will ensure that the nozzles are applying the correct rates and not over or under applying the herbicide. Sprayer tips can break down over time and should be checked with a calibration test before the spraying season to ensure that they are all functioning correctly. If you have had the same set of tips for several years and notice that there are a few not functioning properly, replacing the whole set is recommended.
Before applying herbicides, it is important to ensure proper cleanout of your sprayer. Different herbicides kill weeds in various crops. Herbicide residues may remain in the sprayer on the screens or at dead ends of booms if it is not properly cleaned out, which can lead to crop damage. For example, when moving to spray a canola field after spraying for broadleaf weeds in a cereal crop, there is the potential to pull herbicide residues that had been previously applied with the sprayer. Pulling the herbicide from dead zone(s) or screen(s) in the sprayer can result in damage to your canola fields if the sprayer was not properly cleaned.
With the large variety of crops that are grown on farms, it is important to ensure that your sprayer is not carrying unwanted herbicides from field to field. Using tank cleaner products, such as All Clear or Flush, as recommended on the label ensures that you will not have contamination issues. When applying herbicides, also ensure that the tank mixes are supported and surfactant rates are correct. With surfactants, they are based on water volume application rates, so spraying at 10 gallons per acre requires twice as much surfactant as 5 gallons per acre. Surfactants applied at incorrect rates may result in poor herbicide performance and/or crop injury. When tank mixing herbicides and fertilizer products, ensure that they have been tested and are registered for tank mixing so that the added fertilizer does not reduce herbicide efficacy or damage the crop.