Here's a quick update of pests still infiltrating hayfields in various parts of the country. 

Variegated cutworm damage has been reported across Wisconsin in alfalfa, soybeans and corn, report University of Wisconsin Extension specialists Bryan Jensen, IPM program manager, and Eileen Cullen, entomologist. New alfalfa seedings and established stands have been affected. For more information, click here.

Potato leafhoppers can be found on alfalfa throughout New York, according to Cornell University’s Weekly Field Crops Pest Report. In western New York, Cornell Cooperative Extension field specialist Mike Stanyard reports very high levels of leafhoppers on alfalfa – even over threshold on leafhopper-resistant alfalfa. The rest of the state reports finding leafhoppers, but not at threshold levels. True armyworms are in their fourth week of infestation and found statewide, mostly in grasses and mixed stands.

In western Ontario, armyworms are still being reported in hayfields at high levels in some hot spots, according to Field Crop News, published by the Ontario Ministry of Agriculture, Food and Rural Affairs. Central and eastern Ontario growers have also seen the pest, but not at severe levels. Most infested fields are being harvested. Potato leafhopper (PLH) is the most damaging alfalfa insect pest in Ontario. While its damage isn’t as dramatic as an alfalfa weevil or armyworm outbreak, leafhopper damage is more chronic and widespread. For more information, visit here.