Pesticide injury complaints in 2005
Editor’s note: This article is from the archives of the MSU Crop Advisory Team Alerts. Check the label of any pesticide referenced to ensure your use is included.
MSU Diagnostic Services worked on several pesticide injury complaints in 2005. Pesticides can injure desirable plants by drift, volatilization, carryover, tank contamination, misapplication or simply the accidental or intentional spill or exposure to a pesticide.
All plant samples submitted to our multi-disciplinary plant health and pest diagnostic facility are visually inspected for pesticide injury. If warranted, samples can be tested for the presence of pesticides using appropriate analytical instruments and techniques. This article will briefly explain three cases from 2005 with the injury symptoms observed and our diagnosis of the problem.
Flumioxazin (Valor) plus glyphosate injury on maple
Foliage from several landscape plants contained similar necrotic spots and wilting. The pattern of injury on the property suggested herbicide drift from a neighboring soybean field treated with a burndown of Valor plus glyphosate. Flumioxazin was detected at 0.18 ppm on the foliage. (See Photo)
2,4-D injury on ash
The newer growth of an ash tree contained twisted and cupped leaves. This injury was noticed soon after an herbicide application in a nearby grass pasture. The pattern of injury suggested herbicide drift of a broadleaf herbicide used in the grass pasture. 2,4-D was detected in the tissue. (See Photo)
Tribenuron (Express, component in Harmony Extra) injury on sugar beet
Stunted sugar beet plants submitted to the lab contained elongated petioles and strapped leaves. These injury symptoms can be characteristic of ALS carryover or misapplication. Therefore, soil was analyzed for the presence of several sulfonylurea and imidazolinone herbicides. Only tribenuron was detected in the soil. Tribenuron (Express) is used for weed control in wheat and fall-applied prior to soybeans. Tribenuron plus thifensulfuron (Harmony Extra) is used for weed control in wheat. Either one of these herbicides could have persisted in high pH areas of the field or was a contaminant in the spray tank. Plant samples are visually inspected for pesticide injury for $20. Fees for individual pesticide analytical screens are $90, $100 and $125 in water, vegetation and soil, respectively. Fees for multi-pesticide screens are $125, $150 and $175 in water, vegetation and soil, respectively. Questions regarding pesticide injury should be directed to Steven Gower by phone at 517-432-9693 or by email at