Planning reference

Cutworms vs Armyworms

Separate cutworm soil-line clipping from armyworm egg masses and group defoliation before adding collars, spraying Bt, removing weeds, or re-sowing damaged seedlings.

What each seedling-damage signal means

Cutworms
Cutworms are sturdy moth larvae that feed mostly at night and hide in soil, debris, or plant residue during the day. In seedling beds, the classic clue is a young plant cut off at or just below the soil line.
Armyworms
Armyworms are moth larvae that often begin from fluffy or cottony egg masses. Young larvae can feed together near the egg cluster, skeletonize leaves, chew seedling crowns, and later disperse into broader vegetable beds.
Soil-line clipping and C-shaped larvae
Cleanly clipped stems, missing seedlings, plants dragged below the surface, and a curled C-shaped caterpillar in the top inch of soil point toward cutworms before assuming an above-ground armyworm outbreak.
Egg masses, group feeding, and skeletonized leaves
Fluffy egg masses, clusters of small larvae, lengthwise stripes, black spots on some species, windowpane leaf surfaces, skeletonized foliage, and shallow fruit gouges point toward armyworms.
Night scouting, seedlings, and re-sowing decisions
Both pests can be easiest to find at night, but cutworm decisions center on collars, weed removal, soil checks, and seedling replacement while armyworm decisions center on egg masses, young-larva timing, host range, weeds, and active defoliation.

Caterpillar scouting workflow

Separate clipping from defoliation first
Do not treat every clipped, chewed, or skeletonized seedling as the same caterpillar problem; check soil around cut stems for curled C-shaped larvae, scout at night, look for egg masses, clustered young larvae, stripes, black spots, leaf skeletonizing, fruit gouges, crop stage, row-cover history, weeds, and nearby residue before adding collars, spraying Bt, removing weeds, tilling soil, or re-sowing.
Dig around the newest damage
When seedlings are cut near the soil line, inspect the top inch of soil and nearby residue in the morning and after dark. A hidden curled larva near the base supports a cutworm diagnosis.
Inspect foliage and egg masses
When leaves are skeletonized or many plants show similar chewing, flip leaves, check seedling crowns, and inspect weeds or bed edges for fluffy egg masses and small armyworms feeding together.
Match controls to larva size and location
Collars and weed cleanup help protect vulnerable seedlings from cutworms. Bt and similar caterpillar products work best on small exposed larvae, so buried cutworms and larger armyworms require different expectations.
Re-sow only after the active source is handled
Replace clipped direct-sown crops after removing nearby cutworms or protecting stems. For armyworms, keep checking egg masses and young larvae so new seedlings are not exposed to the same group-feeding pressure.

Use these paths

Source basis