Treatment and Control
Chemical control of spider mites is challenging. While some pyrethroid products may suppress activity of spider mite, nearly all the synthetic pyrethroid products have a detrimental effect on spider mite predators. The lack of full control by pyrethroids allows mite numbers to increase unchecked or “flare up” when conditions are favorable.
Spider mites, like other soybean insects, are found on the undersides of soybean leaves. For optimal control of spider mite populations, use high pressure and a high volume of carrier to achieve thorough coverage and penetration of the crop canopy. Using higher pressures, (40 to 60 psi) and increased carrier volume (15 to 25 gpa) will improve overall performance.
Unfortunately, residual control of most treatments is short-lived, and applications will only control adults and nymphs. Treated fields need to be re-scouted five to ten days following application. It is possible that a second application might be necessary to pick up any newly hatched spider mites, so be sure to scout treated fields about a week after application.
Conditions can change quickly depending on environmental conditions. Heavy rainfall, or changes in temperature, humidity or crop conditions may warrant a re-evaluation of mite populations before treatments are made.