I have noticed that a lot of surfers coast through here from Google looking for information on clothes moths, so while I slog away at PS 136, I thought that I'd take a moment to fill you in on what I know about webbing clothes moths, living as I do with a community of them in this here 200 year old house. I didn't call this blog Moth Heaven just because I think it's a cute name for someone who works with wool; it's a fact of my life. I have only my experience and not an entomology degree, so take this only as opinion, and not as the last word on the subject.
We have moths. I think they arrived on a rug we bought at auction our first year here. So here's lesson number one:
Prevention: when you buy a rug at auction, or acquire anything for that matter that might harbour moths (tapestries, old upholstery, a trunk of clothes for dress-up, some departed knitter's stash) you might feel safer if you first gave it some air and bright sunshine and then heat or cold treat the items. Evaluate the potential for infestation of anything that enters your house. Obviously the wool skirt from Target is a safe bet, but the bag of old sweaters from the Salvation Army you bought for felting projects could have some hitchhikers. Keep such things quarantined in plastic (more on this later) for the time being until you feel safe about them.
Detection: Moths have a long life cycle from what I understand: there are two
crops a year, and they live for almost 90 days once they're hatched. The
little ones you see flitting about are the males. When you see these
guys it means trouble, but killing them will do you little good. It's
the lone female you have to worry abou because she is laying the eggs that hatch into the larvae that
do the damage. She doesn't flit. She hangs out in the back of your
closet on the Alice Starmore sweater you finally finished. Moths have
notoriously uncanny senses of what would upset you the most. They
certainly like wool, but they love expensive wool or hard-won knitting
accomplishments the best.There are expensive Pheromone traps available which are less effective as a way of snaring the little beasts than for determining that you do in fact have a colony working its way through your winter storage closet. You could put one of these traps in a confined space with the item in question to see if it would be worth the cleaning bill for that ballroom sized rug. Male moths are attracted to the scent and become lodged in the sticky space trying to get to the female.
Treatment: I wash things I worry about. Or they get sent to the dry cleaner. It seems common knowledge that moths like soiled things, but in my house, they eat everything, soiled or not. I have things cleaned to get rid of hidden pests, and I favour Eucalan for hand washing both because you don't have to rinse it out, and because it is reputed to have moth deterring qualities. You can iron items to kill eggs and larvae or where that isn't practical, you can leave things in your car trunk in the summer for a few days to cook the little pests, or leave things in the unheated garage in the winter for a few weeks. When you discover something has moth damage, you should assume that it is infested, since the eggs are really hard to detect, and the larvae are very small before they've glutted themselves on your lovely alpaca handspun you bought at the Alpaca Farmers' open house last winter. Vacuum thoroughly anywhere eggs might have fallen when you moved things about, and wash surfaces with soap and water. I know of a knitter who re-painted her closet when she found that she had moved into a house with resident moths, and found that an end to her problem.
Storage: Plastic works for short term storage only. Moths will eat through a plastic grocery in short order, and the heavy plastic zippered bags many of us favour don't breathe and traps moisture with the wool, and moths like moisture and the dark. Zippered cotton pillowcases are the best thing to store yarn in for long term, or plain white paper (hopefully acid-free, but how realistic is that while Martha is in jail?) wrapped fully and taped or tied with a string will keep your wool safe. I keep most of my stash in Rubbermaid bins, which I know, is not a good thing. I think of it more as a way of keeping any potential damage localized to the DK bin or the Magpie bin rather than spreading throughout the whole stash (I have begun a slow acquisition of pillowcases, but my local Kmart only ever has three of them at a time). Because of the semi-annual life cycle, I try to inventory the stash twice a year (it's a lot of fun but a sobering remnder of how little I need to buy any more yarn), and when I do find damage, I take as quick an action as I have time for, if nothing else, throwing the mess into the deep-freeze until I can spend time with it. As for your closets, I don't have a lot of confidence in cedar oil or cedar balls or even cedar-lined closets or any other
aromatics for deterring moths, since they don't seem to care in my
house if there's vats of cedar or lavender oil in the place. Even moth balls,
as loathsome as I find the smell, are probably only effective
within a radius of a few feet; good for trunks and small closets, not
so good for your walk-in. They're the citronella candles of the
closet. I live in a salt marsh; our mosquitoes laugh at citronella.
However, I have heard of plenty of people who claim that they store
their woolens with aromatics and never have had a problem. My attitude
on that is like the old chestnut:
"Why are you wearing that garlic necklace? "
"Because it wards off vampires"
"There's no vampires around here"
"Works well, don't it?"
I read recently in the Fall Spin-Off that there is a spray from Off called Moth-proofer that claims to last for a season, which would be good for applying to baskets and on the outside of storage bags, but I'm not in a hurry to have that in my house because some moth-deterrent products contain carcinogens.
I've become adept at darning and repair, I never get rid of the last bit of yarn after a project is finished because I assume that the moths will love my sweater in direct proportion to how unprepared I am to mend their damage. They seem to adore Rowan Magpie and clean fleece, which I take as a sign of the purity of their tastes. I remain ever vigilant, and I never ever utter out loud anything like "I think we may have finally licked that moth problem" because those words have in the past served as a swift invocation of moth resurgency.
I wish you luck in fighting back, and if anyone has a major disagreement or addenda to what I've offered here, please make use of the comment section.