feeding damage by insects

What you’re seeing

Irregular holes, chewed edges, missing chunks, or ragged leaves; sometimes frass (insect droppings), webbing, or slime trails.

What it is

Physical feeding injury by chewing insects (e.g., beetles, caterpillars) or larger arthropods. Unlike sap-feeders, damage is missing tissue rather than stippling or honeydew.

Is action needed?

Usually yes—both to protect new growth and to avoid secondary infections through wounds.

How to confirm

Timing: Nighttime checks with a flashlight often reveal active feeders.
Signs: Frass pellets, scalloped edges, or slime trails (snails/slugs).
Location: Outdoor and balcony plants are more exposed; indoor cases often hitchhike in soil or on new plants.

What to do

Hand-remove visible pests; drop into soapy water.
Protect new growth: Cover seedlings at night; use copper tape/barriers against slugs/snails for containers.
Spot treatment: Apply a contact spray labeled for chewing insects (e.g., insecticidal soap or pyrethrin) per label; test on a small leaf first. Keep pets away until dry.
For caterpillars on edibles/ornamentals: Consider Bacillus thuringiensis (Bt) products; they’re target-specific when used as directed.
For chewing pests on ornamentals/edibles: Consider spinosad where labeled; apply at dusk and avoid open blooms to protect pollinators.
Sanitation: Remove heavily shredded leaves; keep surfaces clean to avoid inviting secondary issues.
Quarantine new arrivals for 1–2 weeks.

Prevention tips

Inspect nursery plants top and bottom before bringing indoors.
Avoid leaving damp pet food or decaying matter near pots (slug magnet).
Keep outdoor lighting modest; bright lights can attract night-feeding insects.

Sap-sucking injury (pin-prick stippling, sticky residue) is different.
Leaf miners leave winding tunnels rather than holes.