Clothes Moths: It's the Larvae Destroying Your Wool, Not the Adults

The small, golden-tan moth fluttering near your closet isn't eating your clothes. It has already eaten your clothes. By the time you see adult clothes moths, the damage is done. The adults have no functional mouthparts. They don't eat at all. Their sole purpose is to mate and lay eggs on a suitable food source for the next generation of larvae. The larvae are the ones chewing through your grandmother's wool blanket.

Two Species, Same Result

The webbing clothes moth (Tineola bisselliella) is the more common one in North America. Small, about 3/8 inch, uniformly golden or buff-colored, and it avoids light. If a moth flies toward your lamp, it's not a clothes moth. Webbing moth larvae spin irregular silk webbing over the fabric they're feeding on, which is one of the clearest identification clues.

The casemaking clothes moth (Tinea pellionella) is slightly less common. Its larvae build a portable silken case around themselves and drag it along as they feed. You'll find small cigar-shaped tubes, about a quarter inch long, on infested fabric.

Both eat the same things: keratin. That means wool, silk, cashmere, fur, feathers, and felt. Cotton and polyester are safe unless they're stained with food, sweat, or body oils, which the larvae will feed on and damage the fibers underneath.

How to Spot the Damage

Clothes moth damage looks like irregular holes. Not clean, round holes -- those are more characteristic of carpet beetles. Moth damage has ragged edges, often in areas where the garment was folded or stored against another item. You may see sandy, granular frass (larval droppings) in the folds of fabric.

Check garments you haven't worn in months. The larvae prefer undisturbed items. That vintage wool coat in the back of the closet. The cashmere sweaters in the cedar chest. A rolled-up oriental rug in the attic. Items that get worn and laundered regularly are rarely attacked because the physical handling and cleaning disrupts the life cycle.

Treatment Protocol

Start by inspecting every wool, silk, and animal-fiber item you own. Pull everything out of the closet. Look for webbing, cases, frass, and holes. Items with active larvae need immediate treatment.

Dry cleaning kills all life stages. It's the fastest solution for garments that can handle it. Expect $8 to $25 per item depending on size.

Freezing works for items that can't be dry cleaned. Seal the item in a plastic bag, squeeze out the air, and place it in a chest freezer at 0 degrees Fahrenheit for a minimum of 72 hours. This kills eggs, larvae, and adults. A standard kitchen freezer set to 0F works fine. Don't rush it. Three full days.

Hot washing at 120F or above also kills all stages, but most wool and silk can't handle that. Only use this for sturdy items like wool blankets that are machine washable.

While items are being treated, vacuum the closet thoroughly. Every shelf, every corner, the baseboards, the carpet underneath. Pay attention to cracks where the carpet meets the wall. Larvae often pupate in these gaps. Empty the vacuum bag or canister into an outdoor trash bin immediately.

Monitoring and Prevention

Pheromone traps are essential for knowing if you still have a problem. The Pro-Pest Clothes Moth Trap ($8 for a two-pack) uses a synthetic pheromone to attract adult male webbing clothes moths. Hang one in each closet. If you're catching moths on the trap, larvae are still active somewhere. If the trap stays empty for 8 to 10 weeks, you've likely cleared the infestation.

Cedar blocks and cedar hangers do repel adult moths from laying eggs, but they won't kill larvae that are already feeding. The aromatic oils in cedar diminish over time. Sand the surface lightly every 6 months to refresh the scent, or apply cedar oil. Our common pests guide covers carpet beetles, which cause similar damage and often get confused with moths.

Mothballs work. That's not debatable. The active ingredients (naphthalene or paradichlorobenzene) are toxic fumigants that kill moths at all life stages in an enclosed space. The problem is that both chemicals are classified as possible carcinogens, they smell terrible, and the odor transfers to clothes. They need to be used in an airtight container, not just tossed in an open closet. Follow the label exactly.

Professional Treatment

For a severe infestation that's spread to multiple rooms, a pest control company can treat with residual insecticides applied to carpet edges, closet floors, and fabric storage areas. Cost ranges from $200 to $400 depending on the scope.

Clean before you store, store in sealed containers, and check twice a year. That's the entire prevention strategy. Clothes moths don't appear out of nowhere. They came in on something: a thrift store purchase, a hand-me-down coat, a vintage rug. Inspect and clean every secondhand animal-fiber item before it goes in your closet.