Rose skeletonize

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Rose skeletonize is the larval stage of a  flying insect known as a sawfly. They do resemble small slugs but are not slugs. Rose sawflies are yellow-green in color and can grow to a ¾ inch maximum length.  

These larvae feed on the surface of leaves of their respective host plant, removing the soft tissue leaving behind the papery, translucent surface and veins. Heavy defoliation gives plants a brown scorched appearance. In most cases the plant will recover if there is no other underlying problem.  This feeding is different than Japanese Beetles which cause more of a lacing effect versus the translucent window paling.

Adult sawflies usually emerge in early spring and lay their eggs on the underside of host plant leaves. Larvae appear several weeks later, feed on soft leaf tissue for about a month, and then drop into the soil to pupate. 

This pest is fairly easy to control with contact sprays of insecticides or systemic insecticides.  

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