Answer: According to the University of Ohio, Columbine sawfly is a common pest in your area and larvae can be found devouring leaves of columbines in late spring. These larvae are green with dark heads. They start feeding on the leaf edge and eat inward and devour all leaf tissue except the mid-veins. The resulting damage make plants look like they were sprouting match sticks.
After feeding for a few weeks in late spring, they drop from the plant and pupate. Adults then emerge within a few weeks. There is one generation per year. Control is possible with insecticidal soap, spinosad, or pyrethroid insecticides. Be sure to follow the label directions.
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