How to spot moth damage in wool rugs before it spreads.

What actually eats your rug

It is almost never the moths you see fluttering around a lamp. The damage is done by the larvae of two pests — the webbing clothes moth and the carpet beetle — and they feed on the one thing wool is made of: keratin, the same protein found in hair and feathers. Synthetic fibers (nylon, polypropylene) are safe. Cotton and silk are at lower risk. But wool, and especially wool that carries a little body oil, food residue, or pet dander, is exactly what they are looking for.

That is the key thing to understand: moths are drawn to soiled wool. A clean rug in regular use is a poor target. A wool rug left undisturbed in a quiet corner, under a bed, behind a sofa, or rolled up in storage is the ideal one. Lack of light and lack of foot traffic matter more than anything else.

Where the damage starts (and why you miss it)

Larvae avoid light and disturbance, so they work in the places you never look. By the time damage is visible on the face of a rug, the colony has usually been active for months. The order of discovery is almost always the same:

• Under furniture and along the edges — the static zone beneath a sofa, bookcase, or bed is the first place to fail. Foot traffic in the open part of the room keeps larvae away; the dead air under furniture does not.
• The back of the rug, before the front — larvae often graze the foundation and the base of the pile first, eating the wool from underneath. You can have significant damage on the back while the surface still looks intact, until a patch of pile suddenly lifts away because nothing is holding it anymore.
• Rolled or stored rugs — a rug in storage is dark, undisturbed, and frequently put away without a proper cleaning first, the worst possible combination. Storage damage is often discovered only when the rug is unrolled the following season.

The early warning signs

Catching moths early is entirely a matter of knowing what to look for before the bald patches appear. In rough order of how early they show up:

• Fine, sandy grit in the pile — run your hand through the pile in a quiet area and look at what falls out. Larvae leave behind tiny tubular casings and “frass,” digested wool that looks like fine sand or pepper, often tinted the color of the rug. This is the single most reliable early sign.
• Silky webbing or tunnels — webbing-moth larvae spin fine silken threads and tubes along the foundation, sometimes matting bits of fiber together. Lift the corner of the rug and look at the back near the edges.
• Pile that feels thin or “mowed” in patches — before wool disappears entirely, larvae crop it short. A patch that sits noticeably lower than the surrounding pile, especially under furniture, is active feeding.
• Small moths near the floor — clothes moths are weak fliers and avoid light; you will see them creeping along baseboards or fluttering low near a rug, not circling the ceiling like pantry moths. Seeing the adults means a breeding population is already established.

A two-minute inspection you can do today

Pick the quietest wool rug in the house — the one under a bed or behind a couch. Fold a corner back and look at the foundation. Run your fingers against the pile in the most undisturbed area and check your palm and the floor beneath for grit and casings. Press the pile to feel for soft, low, or loose patches. Do the same along all four edges. If the rug is in storage, unroll it fully and inspect the center as well as the ends. The whole thing takes a couple of minutes and is worth doing two or three times a year.

If you find active moths

Speed matters — an established colony keeps eating every day you wait. The steps, in order:

• Isolate the rug — get it away from other wool textiles immediately so the infestation does not spread to nearby rugs, upholstery, or clothing. Roll it and move it out of the room if you can.
• Vacuum thoroughly, both sides — vacuuming removes eggs, larvae, and casings mechanically and is the most useful thing you can do at home. Pay special attention to the back and the edges, and empty the vacuum outside afterward so you are not relocating live larvae.
• Do not reach for a steam cleaner — hot water and household cleaning will not reliably reach larvae buried in the foundation, and steam cleaning carries its own risk of damaging wool. See why steam cleaning damages wool rugs. Surface treatment at home does not solve an embedded infestation.
• Get the rug professionally cleaned — a proper full-immersion wash removes the soil that attracts moths in the first place and flushes out eggs and larvae the vacuum missed. This is the step that actually ends the cycle.

Repairing what the moths left behind

Once the infestation is stopped, the missing wool does not grow back — it has to be rewoven. The good news is that on a hand-knotted rug this is entirely fixable. Small bare patches can be patched; larger losses are rebuilt knot by knot through hand reweaving, matching the original wool, color, and knot count so the repair disappears into the surrounding field. The earlier you catch the damage, the smaller and less expensive the repair — another reason early detection pays off. For a sense of when extensive damage is worth repairing, see repair vs. replacement.

Preventing the next infestation

Prevention matters most in the warm months, when moths breed and larvae feed — our summer rug care guide puts moth defense alongside the season’s other risks. It is mostly about denying moths the dark, undisturbed, soiled wool they need:

• Clean wool rugs on a sensible schedule — soil is the attractant; removing it removes the invitation. See how often you should clean an oriental rug.
• Move furniture and rotate rugs periodically — disturbing the static zones a few times a year disrupts feeding and gives you a chance to inspect.
• Vacuum the hidden areas — under furniture and along edges, the exact spots that get skipped in normal cleaning.
• Store rugs correctly — never store a wool rug dirty, and never seal it in plastic. Professional mothproofing treatment plus proper storage is the reliable way to protect a rug you are putting away for months. Our full guide to storing oriental rugs the right way covers the details.

Bottom line

Moth damage is quiet, hidden, and entirely preventable. The larvae feed on soiled wool in dark, undisturbed places — under furniture, along edges, on the back of the rug, and in storage — so that is exactly where you should look. The earliest signs are fine grit and casings in the pile, not bald spots. If you find an active infestation, isolate the rug, vacuum both sides, and have it professionally cleaned; whatever wool was lost can be rewoven afterward. And the best protection is the simplest: keep wool rugs clean, move them around, and never store them dirty.