How to Grade Moth Holes in Used Wool Knitwear: Holes, Pulled Loops, and Snags

To grade moth holes in used wool knitwear, confirm the cause first: moth damage is a break in the yarn and caps most sweaters at Fair or Poor, while a pulled loop or surface snag is a displaced yarn that often stays in Very Good or Good. Then check the area around any hole for live larvae before the garment goes near your other stock.

Here is the scenario we see often. A seller lists a gray merino crewneck as Excellent. The buyer opens it, finds three pinholes near the hem, and files a not-as-described return. The seller called them snags. They were moth holes, and the listing never had a chance. This guide gives you a repeatable way to sort the two, grade them against the Fabric Condition and Structural Integrity factors, and protect your inventory.

Moth Holes vs. Pulled Loops vs. Snags: What You Are Looking At

Three different defects get lumped together as holes. They have different causes and different grade effects, so name them correctly.

• Moth damage: Larvae eat the wool protein. The yarn is broken or thinned, not moved. Holes are often small, round to ragged, and clustered in dark, undisturbed places like underarms, folds, cuffs, and under collars.
• Pulled loop (a snag with a long tail): A loop of yarn has been tugged out of the knit, leaving a visible pucker and a raised loop. The yarn is intact. Nothing is missing.
• Surface snag: A single fiber or small loop sits proud of the surface. There is no distortion to the surrounding stitches or only a faint one.

The key test is whether yarn is missing. If you can trace every strand across the area, it is a pull or snag. If a strand ends or is visibly thinned, it is a break, and a break needs a closer look.

The Comparison Table: How Each Defect Reads

Treat the tier effects as starting points. Size, count, and placement move the grade within the range.

The Seven-Step Check Before You Grade

Run this sequence on every wool or wool-blend knit. It takes about three minutes per piece once you have the habit.

1. Isolate the garment. Bag it or keep it away from other wool until you finish steps 3 and 4. That protects your stock if there is an active problem.
2. Turn it inside out and scan in raking light. Hold a bright light at a low angle across the knit. Thinned patches show as shadowy, sparse areas. Inspect folds, underarms, cuffs, neckband, and hem first.
3. Check the area around every hole for larvae evidence. Look for small silky cases or tubes, fine webbing, and gritty specks (frass, which looks like tiny colored grains matching the yarn). Live larvae are small, pale, and worm-like. Any of these means the garment is active, not just damaged.
4. Shake it over white paper. Tap the damaged area. Specks or case fragments falling out confirm recent activity. Clean paper does not prove it is safe, but it is useful evidence.
5. Trace the yarn across each defect. Use a pin or fingertip. If every strand continues, it is a pulled loop or snag. If a strand ends or frays, it is a break.
6. Stretch gently across the defect. Pull the surrounding knit about an inch in two directions. A moth hole often opens or shows thinning. A pulled loop puckers and stays closed.
7. Count, measure, and place. Record how many defects, the size of each in millimeters, and the location (front chest, underarm, hem). This sets the grade and drives the disclosure.

Checking for Active Larvae Before You List

Grading and quarantine are separate decisions. A garment with old, inactive damage can still be sold with disclosure. A garment with live larvae should not ship until it is treated, and it should not sit with your other wool.

Evidence of activity includes live larvae, fresh frass, intact cases, and fresh webbing. Evidence of old damage includes clean-edged holes, no debris, and no cases after a shake test.

If you see activity, common seller practice is to freeze the item sealed in a bag for several days, or to wash or dry-clean it if the care label allows. Follow the label and use your own judgment. We are not claiming any treatment guarantees the garment is clear, so recheck after treatment and before listing. Then clean the storage area, since larvae and cases can sit in shelves and boxes.

Odor & Cleanliness matters here too. A musty or stale smell next to damage suggests long storage. Note it in your grade, and do not hide it in your description.

How to Set the Tier by Defect

Use the five factors to score. Moth damage lands mostly in Fabric Condition and Structural Integrity. Pulls and snags land mostly in Cosmetic Appearance.

Moth holes

• One or two pinholes, hidden, such as inside an underarm: Good to Fair. Size matters. A hole under a few millimeters that is not at the front is still a break in the yarn, so it should not sit above Good.
• Several holes or any hole on the front chest or sleeve: Fair. Buyers see it immediately.
• Clusters, thinning patches, or active infestation: Poor (3–4). The Fabric Condition factor has failed, and the garment may need quarantine and treatment.

Pulled loops

• One small pulled loop, not distorting the knit: Very Good, if the rest of the garment is clean.
• Multiple pulls or a visible pucker on the front: Good.
• A pull that has stretched stitches or pulled a run: Fair, because Structural Integrity is now affected.

Surface snags

• A few raised fibers, no distortion: Excellent or Very Good, depending on the rest of the garment.
• Many snags concentrated at the sides or sleeves from bag or seatbelt friction: Very Good to Good.

Remember the tier definitions. Excellent is light wear with no visible defects at normal distance. A garment with any moth hole is not Excellent, whatever the brand or fiber.

What to Write in the Listing

Name the defect by what it is. Say pulled loop when it is a pulled loop, and say small hole when you cannot rule out moth damage. Do not use vague words like flaw or mark.

• Include location, count, and size: three holes under 3 mm at the left underarm seam.
• State whether you checked for activity and what you found: no larvae, cases, or webbing found; item sealed and frozen before listing.
• Photograph each defect with a ruler or coin for scale, one close shot and one at arm's length.
• Match the condition label to the grade. On eBay, tiers like Pre-Owned are broad, so put the specifics in the item description and the photos. Do not rely on the dropdown to carry the message.

Defects named in photos and text are the best protection against a not-as-described claim. A buyer who knew about three small holes has little to dispute.

Common Mistakes

• Calling a hole a snag. If the yarn is broken, it is not a snag. Buyers who find a hole after you wrote snag will say you misled them.
• Grading from the outside only. Turn the garment inside out. Damage often shows first on the reverse.
• Skipping the area around the hole. The hole you can see is rarely the whole story. Check the surrounding knit for thin spots.
• Storing the item with the rest of your wool. Until you have cleared it, keep it apart.
• Overcalling a pulled loop. A single pulled loop that can be eased back into place with a needle is a minor Cosmetic Appearance issue. Do not drop the tier two steps for it.

Grade One Sweater and Compare

Pick one wool knit with a defect you are not sure about. Run the seven steps, then grade it in GradeThread to see the report: a numerical grade from 1.0 to 10.0, a breakdown across Fabric Condition, Structural Integrity, Cosmetic Appearance, Functional Elements, and Odor & Cleanliness, and a certificate a buyer can verify. Compare it to your own call. If they match, you have a method. If they do not, you have found a gap before a buyer did.