For information on herbicide injury please see the article "Dealing with Drift" from Iowa State University Weed Science.
Iowa State University Plant & Insect Diagnostic Clinic DOES NOT offer chemical residue testing. We can investigate f the symptoms observed may be related to other common problems including disease and insect damage. Please see our website for current forms, fees, and instructions on collecting and packing samples. Contact information for each states diagnostic laboratory for U.S. residents can be located at the NPDN website. If you have a sample from outside of Iowa, please DO NOT submit it to the Plant & Insect Diagnostic Clinic without contacting us.