Clothes Moths in Ontario

Overview

Clothes moths are the reason a favourite wool sweater comes out of storage with holes no one put there. Two species turn up in Ontario homes — the webbing clothes moth (Tineola bisselliella) and the casemaking clothes moth (Tinea pellionella) — and both do their damage as larvae feeding on keratin, the protein in animal fibres. Unlike pantry moths, which fly openly around a kitchen, and unlike the carpet beetle whose larvae attack the same wool, clothes moths are secretive: they avoid light, flutter weakly, and hide in the dark, undisturbed places where wool and fur sit for months. Most homeowners discover them by the damage, not the moth — which is exactly why the population has usually been feeding for a while by the time it’s found.

Identification

Adult clothes moths are small, 6 to 8 mm long, with a narrow buff-gold body and a weak, reluctant flight. The webbing clothes moth is a uniform buff colour with a small tuft of reddish hairs on top of its head; the casemaking clothes moth is similar but shows faint dark specks on the wings. The larvae are creamy-white caterpillars up to about 12 mm. The two Ontario indoor moths are easy to separate once you know where and how they behave.

The two clothes moth species also differ in their trace: webbing moths leave loose silken webbing and gritty fecal pellets on the fabric, while casemaking moths carry a portable silken tube — a “case” — woven from the fibres they eat, which they drag along and hide inside.

Life Cycle

A female lays her eggs directly on suitable material — wool, fur, or a soiled natural fibre. The larvae hatch and feed, and this stage does all the damage and lasts by far the longest: development from egg to adult ranges from about one month in warm conditions to as long as two years when it’s cool and food is marginal. In a heated Ontario home the cycle runs on the shorter end, and because the larvae feed slowly and secretly, an infestation can persist and spread through a closet across many months before it’s noticed.

Habitat & Behaviour

Clothes moths seek out dark, still, undisturbed spaces stocked with animal fibres: closets, dresser drawers, under-bed storage boxes, garment bags, attic and basement storage, and the underside of wool rugs where furniture keeps them from being disturbed. The adults are poor fliers that avoid light and tend to run or hop into shadow when disturbed, rather than fly across the room. This preference for stillness is why seldom-worn heirloom garments, stored winter woollens, and rug edges under furniture are the classic damage sites.

Diet

The larvae eat keratin, found in wool, fur, silk, felt, feathers, and leather. They generally ignore cotton, linen, and synthetics — unless those fabrics are heavily soiled with sweat, food, or body oils, or blended with wool, in which case they’ll feed on them too. Soiling matters a great deal: larvae strongly prefer fibres stained with perspiration or food residue, which supply extra nutrients, and that preference is why damage clusters at the underarms, collars, and cuffs of stored clothing. The adult moths have no functional mouthparts for feeding and cause no damage themselves.

Signs of Infestation

• Irregular holes and threadbare patches in wool, fur, or silk, often concentrated on soiled areas like underarms and collars — the most common first sign.
• Silken webbing or portable silken cases on the fabric surface, depending on the species.
• Gritty fecal pellets the colour of the fabric being eaten, sifting out of folds.
• Creamy-white larvae tucked into seams, folds, or rug pile.
• Small buff moths running or fluttering weakly from a closet when it’s opened.

Damage Caused

Damage is confined to natural-fibre goods, but within that category it can be costly: wool coats and sweaters, silk, fur, felt hats, heirloom textiles, tapestries, feather items, and the underside of wool area rugs. Because larvae favour undisturbed material, the most valuable and least-worn items — stored winter woollens, keepsake garments, antique rugs — are often the hardest hit. The holes are permanent; unlike a stain, there’s no cleaning the fibre back.

Health Risks

Low. Clothes moths don’t bite, sting, or transmit disease, and they pose no direct health threat to people or pets. The concern is purely the destruction of valuable natural-fibre belongings. There’s no medical reason for alarm — but there’s a strong financial reason to catch them early, before a whole stored wardrobe or an heirloom rug is lost.

Seasonal Activity in Ontario

Clothes moths are far less seasonal than pantry moths because heated Ontario homes give them warmth year-round, so a closet population can breed through the winter. That said, problems most often come to light in spring and fall, when wool clothing is packed away or pulled back out and the damage becomes visible. The insects don’t go dormant indoors the way outdoor pests do — a warm, quiet closet in Toronto, Vaughan, or Oakville is a year-round habitat.

Where They Hide

In the folds of stored wool and fur, deep in closet and drawer corners, inside garment bags and storage boxes, under the pile of wool rugs held still by furniture, and in the dark quiet of attic and basement storage. Casemaking larvae hide inside their silken tubes, which blend into the fabric. Anywhere dark, undisturbed, and stocked with keratin is a candidate, which is why a thorough inspection means unfolding and checking stored items, not just glancing at the closet.

How They Enter Homes

Often they arrive on an already-infested item — a second-hand wool coat, a vintage rug, an inherited textile, or a garment that picked up eggs in storage elsewhere. Adults can also fly or be carried in through open windows and doors, though their weak flight makes long journeys unlikely. Once inside, a single mated female laying on a wool sweater is enough to start a closet population, which is why inspecting used natural-fibre goods before bringing them home is worthwhile.

Prevention Tips

1. Launder or dry-clean natural fibres before storing them — clean wool is far less attractive, and it removes the sweat and food residue larvae prefer.
2. Store woollens in sealed, tight-fitting containers or garment bags the moths cannot enter.
3. Vacuum closets, drawers, rug edges, and baseboards regularly to remove eggs, larvae, and lint.
4. Rotate and air out stored items periodically — disturbance and light discourage a species that depends on stillness.
5. Freeze at-risk or suspect items at about -18°C for a week to kill any eggs and larvae before storage.
6. Use pheromone traps in closets to detect a problem early, while it’s still one garment rather than a wardrobe.

DIY vs. Professional Treatment

A contained clothes moth problem is often a do-it-yourself job: find and treat the infested items by hot laundering, dry-cleaning, or freezing; vacuum the storage area thoroughly, including cracks and rug edges; move clean goods into sealed storage; and monitor with pheromone traps. The difficulty is that larvae hide in folds and cracks, and eggs left behind in a closet corner will restart the cycle on the next wool item stored there. When damage keeps appearing after cleaning, spans multiple rooms, or threatens valuable textiles, professional treatment locates and treats the full extent of the infestation — backed by Sani IQ’s Pest-Free-Or-It’s-Free guarantee. Our residential pest control service begins with a proper inspection to find every source, and treatment pricing is on the plans and pricing page.

References

• University of Kentucky Entomology — Clothes Moths
• UC IPM — Clothes Moths
• University of Minnesota Extension — Clothes Moths

Last updated: July 16, 2026 · Reviewed by Sani IQ licensed technicians