A website from UGA Cooperative Extension


As we finish the last at cracking herbicide sprays, and move into the first of our fungicide and post emergence herbicide applications, I wanted to share information pertaining to tank mix combinations.  Dr. Eric Prostko urges caution when combining a variety of products into one tank mix. Of course, we all want to save time, diesel, and trips back over the field.  But, whenever there is a high percentage of chemicals opposed to water there can be an increase in injury to the crop.  The result of multiple  products in a tank mix may be cosmetic injury, detrimental crop injury, and/or loss of control over targeted species.  Dr. Prostko has conducted extensive research and observed countless trials with numerous tank mix combinations, all with varying degrees of injury.  It is important to remember that anytime we mix more than 3 products together we cannot be confident that the  level of injury will be acceptable.  The levels of injury observed can range from no injury to severe and may not be consistent from field to field or even day to day.   The degree of injury can be impacted by numerous factors including; how the crop is growing, temperature, time of day, and humidity.  When injury occurs,  it is very difficult to pin point that any one particular product can be credited for the resulting problem.  It is almost always the combination of products that has enhanced the damaging effect.  Also, while some tank mixes result in crop injury, still others have compatibility issues in mixing.  The tank mix compatibility problems can result in negative effects on equipment.  The possibility of combinations in a tank mix can be endless when we consider meeting nutritive needs of crop, weed control, insect control, and disease control.  I have copies of a regional publication that summarizes what could happen (good or bad) in peanuts with many tank mix options.  If you would like a physical copy of this publication please give our office a call and we will get it to you. The link to this publication is also attached below.