Cutworms
Family Noctuidae (larvae)
Plump, soft caterpillars that hide in the soil by day and come out at night to chew through the stems of young seedlings at ground level, felling them like tiny trees. A gardener often finds a row of transplants cut off and lying on the soil one morning with no culprit in sight.
🔎 How to spot it
Cutworms are smooth, dull gray, brown, pink, or greenish caterpillars up to about two inches long that curl into a tight C shape when disturbed. They feed at night and hide by day just below the soil surface or under debris at the base of plants, so the tell is the damage plus a caterpillar found curled in the soil when you dig nearby.
🥀 Damage it causes
They chew through the stems of seedlings and transplants right at or just below the soil line, toppling or severing the plant; a single cutworm can cut down several plants in a night. Some species also climb to feed on leaves and buds. Young, tender seedlings are by far the most vulnerable, and damage is heaviest in spring.
🛡️ Prevent it
Ring each transplant with a collar, a cardboard tube, a tin can with both ends out, or foil, pushed an inch or two into the soil and standing a few inches above it, so the cutworm cannot reach the stem. Clear weeds and debris that shelter them, and cultivate the bed a week or two before planting to expose and disrupt larvae. Keep the area around seedlings clear and firm.
🧯 If it is already here
Hunt at night with a flashlight and handpick the caterpillars, or scratch the soil around a freshly cut plant to find the culprit curled an inch down and destroy it. For bigger outbreaks, an evening application of Bacillus thuringiensis (Bt) or spinosad on and around seedlings helps. Replace cut transplants and protect the new ones with collars.
💡 Good to know
Cutworms are the night-feeding caterpillars of several drab moth species, and they overwinter as larvae or pupae in the soil, ready to attack the earliest spring plantings. Because they do their damage in the dark and hide by day, a flashlight hunt and simple stem collars are far more reliable than waiting to catch them in the act.
🌱 Plants it attacks
714 plants in the library can be attacked by this pest
Agapanthus
Ageratum
Anemone
Angelonia
Annual VincaFor educational and informational purposes only. Pest control advice is general guidance drawn from university cooperative extension sources; always identify a pest positively and read and follow the label on any product before use, especially around food crops, children, and pets.