Managing the pesky insect known as the roseslug sawfly

Activity from the roseslug sawfly is being seen in our county. The symptoms are white or tan areas on rose leaves, also called windowpaning, as a result of insect larvae eating away the surface area of the leaf between the veins. The rose will grow new leaves to replace the browsed ones. But if a homeowner would like to manage the situation, then monitoring the plants for early signs of eggs and larvae is the best practice. A strong jet of water may dislodge them, or a spray of soapy water may also disrupt them. Squishing them by hand is particularly effective, though not practical for a large planting. — Lisa Chiariello is the Master Gardner coordinator for Rutgers Cooperative Extension of Sussex County.