Time To Scout For Potato Leafhopper

Jun 10, 2015

It is time to have your sweep net out and be scouting for potato leafhopper (PLH) in your alfalfa field. The recent rains have brought PLH into our region from the south where they overwinter. So, get that sweep net out and start checking to see if they are in your alfalfa fields. The piercing and sucking feeding of PLH means that their feeding isn’t obvious and damage (stunted plants and yellowing leaves) won’t show up until a few weeks after feeding. Consequently, scouting with a sweep net is the best method to determine when you need to spray.

IPM of PLH requires knowing the value of the silage or hay. Below is the updated threshold chart with higher values than in older charts.

Source:psu.edu

Video: Wisconsin Corn and Soybean Weed Management Updates and Considerations for 2026 and Beyond

Dr. Rodrigo Werle, associate professor and extension weed scientist, UW–Madison, shares the latest updates and future considerations for corn and soybean weed management in Wisconsin. This presentation covers herbicide resistance trends in waterhemp, including newly confirmed cases of HPPD and S-metolachlor resistance, and emphasizes the importance of residual herbicides and strategic tank mixes for consistent control. Rodrigo also introduces upcoming technologies like Vyconic soybeans and new herbicide products, discusses integrated weed management strategies such as planting green with cover crops, and highlights practical recommendations for 2026 and beyond.

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