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Sawfly Larvae on Pines: Mechanical Control to Protect Monarch Milkweed

Susie in Minnesota had sawfly larvae defoliating Norway pines. She raises monarchs on milkweed nearby and needed a caterpillar-safe solution before a graduation party in 2 days.

The expert said most sawflies eat only older needles, rarely killing trees. No insecticide spares monarch caterpillars. Mechanical removal: hand-pick, knock off with stick or strong water spray. Best done when larvae are young. Sorry—no quick chemical fix.

Safe Options

Hand-pick or dislodge with water jet.
No insecticide safe for monarchs.
Sawflies rarely kill pines (eat old needles).
Act quickly before party.

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