Sawflies
Larvae that look like small caterpillars or tiny green slugs but are actually wasp relatives. They graze the surface off a leaf and leave a see-through window, or strip the leaf down to its veins.
Pest checklist
Four things to look for. If most of them match what you are holding, you are in the right place.
What gets rid of them
Gentlest option first. For most backyard cases the first one is enough, so try these in order and stop as soon as it works. If you do spray something, the product label tells you how — please read the notice further down.
1Hose them off
A hard jet of water knocks the soft larvae off the leaf, and they cannot climb back up.
Try this first2Hand-pick
Turn the leaves over and wipe or pick the larvae into soapy water. Most of the damage comes from a few clusters.
3Insecticidal soap or horticultural oil
Wet the undersides of the leaves while the larvae are still small. Coverage matters more than which product you pick.
insecticidal soap concentrate4Spinosad for a heavy attack
Labeled spinosad products do work on sawfly larvae. Spray in the evening so bees are not working the plant.
spinosad garden spray5Skip the Bt
Bacillus thuringiensis will not touch sawflies. If a Bt spray did nothing, this is why.
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Which plants get sawflies
Every plant we cover that gets sawflies, grouped by type — tap any one to open its page. A note beside a plant came from that plant’s own entry, because the same pest can be a minor nuisance on one plant and a serious problem on another. Plenty of plants we do not cover get it too.
trees4
shrubs4
biennial1
Plant families hit hardest
Related plants often share the same problems, so if one plant in a family has it, check the others. The largest group here is Rosaceae, with 4 of the 11 affected plants.
- Rosaceae4 plants
- Grossulariaceae3 plants
- Malvaceae2 plants
When to treat
Treat on sight, while the larvae are small. One thing to know up front: Bt does not work on sawflies. They are not caterpillars, so Bt sprays are wasted here.
Timing only — the label is the law
This page tells you when to watch for sawflies and when treating is worth considering. It is not a recommendation to apply any particular product. Read and follow the product label before you spray — under federal law the label is the legal instruction, and using a pesticide against it is illegal.
- Check the pre-harvest interval. Every product that’s cleared for an edible crop sets a minimum number of days between spraying and picking. Find it on the label before you spray anything you intend to eat.
- Check the re-entry interval before you or anyone else works in the treated area again, and use the protective equipment the label names.
- Confirm the product is registered for your crop in your state. This page groups many different crops together, and a product legal on one of them is not legal on all of them — state registrations differ too. Your state pesticide agency or local extension office can confirm both.
- Rates and mixing instructions come from the label, never from us. We don’t publish them because they differ by product and formulation.
Other problems on the same plants
If a plant gets sawflies, these are the problems it most often gets as well, so they are worth checking for while you are out there. They tend to appear together; one does not cause another.