Pest

Squash vine borer

Melittia cucurbitae

The larva of an orange-and-black clearwing moth that bores into the base of squash and pumpkin vines in early summer and feeds inside.

Signs

A vine wilts in strong sun at first, then stays wilted, while the soil is moist.
A hole near the base with greenish, sawdust-like frass.
A fat white larva with a brown head inside the slit stem.

Squash and pumpkin planted where the pest was last year; moths fly from mid-May to July, depending on region.

Row cover from planting until flowering (hand-pollinate or uncover for bees once flowers open).
Plant butternut squash (Cucurbita moschata), which resists the borer.
Sow a second planting of summer squash in early July, after the moth flight.

Cucumber, squash & melon.

Treatment by crop

Cultural, biological and chemical options in the order to use them, and notes written for each crop.

Identification is free. Treatment is on the Home and Pro plans.

Open in the key See plans

Look the plant over, leaf undersides included. Are insects, mites, slugs, eggs, webbing or droppings on it?
Yes, something living or its traces
What is on the plant?
Something chewing
What is doing the chewing?
A hole at the base of a squash vine, with sawdust-like frass

Not a match? Start the key or describe what you see.

More from university Extension: search Extension pages on squash vine borer, or find a plant diagnostic lab through your state's Extension.