Haven’t read When Moths Attack Part I: Introduction and Identification? Click here!
Now that you know what types of moths cause damage and how to identify them, I’m going to cover how to eradicate them and prevent them from coming back. However, as always, please don’t use these methods with historic textiles! They are very fragile and have special requirements. If you have a historic textile that you believe may have a moth infestation contact a local textile conservator.
Eradication
Eradication is a more eloquent way of saying the complete destruction of something. Unfortunately you can’t politely ask moths to stop eating your wool, but luckily there are ways to get rid of them.
Freezing
The easiest way to kill moths without damaging your wool is by freezing them. Place your items into plastic bags, remove as much of the air out as possible, and put the bags in your freezer for at least two weeks. After freezing, let the bags return to room temperature and remove the textiles. Note: If you have a variety of wool and other fibers together in the infested area, it’s best to freeze everything. This ensures that no pests are hiding in your cotton yarn!
What if you have too much wool for your freezer? You can freeze things in batches, but you need to reduce the risk of moths re-infesting your already frozen wool. Once you take the wool out of the freezer, keep it in its sealed bag away from the untreated wool. Luckily, moths can’t eat through plastic!
If your woolen object is too large for a freezer, such as a carpet, you should try contacting a textile conservator in your area for help. Check out my list of further resources to find a conservator near you!
Other Methods
The opposite can also kill moths. Heating textiles to 55° C (131° F) can eliminate moths, but can also put textiles in a lot of danger if not done by an expert. Raising the temperature without raising the relative humidity can cause fibers to dessicate, leaving them dry and brittle. Some materials commonly found in textiles, such as plastics, can also be permanently damaged by high heat. I wouldn’t recommend this method of eradicating moths. I’m only mentioning it here because I have seen other articles suggest this technique.
Another option for eradication are pesticides. Textile conservators generally avoid them because: A. We aren’t trained in using them B. They can harmful to human health and C. We don’t know the long term effects of them on textiles. However, if you would like to try this route, I suggest contacting a professional exterminator to ensure the safe eradication of the insects.
Clean Up
After killing the moths comes the gross part: removing all of their corpses. Dead moths, larvae, and frass can attract other insects who eat them. Practically, you also probably don’t want to spin fiber with dead moths in it. I suggest doing the following outside or on an old sheet because it’s going to get messy.
You can start by giving the textiles a gentle shake. This will remove a lot of the frass and some of the remains. Then closely inspect all of your wool, using tweezers to remove any moths or larvae. Try to check everywhere! Unloop braids of fiber, rewind hanks of yarn, and unfold bolts of fabric. Moths dislike light, so they often hide inside or on the underside of textiles.
This is also a good time to decide what is destined for the bin and what is salvageable. Try to be realistic about what you think you can actually use. Depending on what has been damaged, it may be more difficult to repair. For example, if wool roving has a few chunks missing those short fibers can simply be pulled out and the rest spun like normal. But if a jumper is full of moth holes, each hole will need to be darned before you can safely wear it again. Unsurprisingly, as a textile conservator I recommend repairing things rather than replacing them!
Now that all of your wool is free of moths, you can wash your textiles according to their care instructions. For wool fiber, yarn, and fabric, this is generally in with cool water, minimal agitation, and a wool appropriate detergent. After air drying, your wool should be clean and moth free!
Prevention
However, to keep it that way you need to prevent another moth infestation. Conservators use a system called integrated pest management or IPM to deal with the threat of pests. This is a system that prevents pests from multiplying in a collection, recognizes when there is a problem, and solves the issue when the need arises. Essentially this means that you don’t wait until an infestation starts to begin thinking about pests.
Storage
One of the easiest things you can do to prevent a moth infestation is make it difficult for them to access your wool in the first place. Arranging your wool collection on an open shelf may look lovely, but it does nothing to prevent moths from getting to your fibers. I recommend storing wool in sealed plastic containers. Make sure to inspect objects before placing them into the container though or you may be trapping the moths with their food!
This doesn’t mean that you can’t have carpets, wall hangings, or other woolen object on display in your house though! Just understand that having textiles out puts them at more risk of moth damage and counter this by monitoring them for pests.
Monitoring
Monitoring means examining your woolen textiles for moths or evidence of them (see Part I: Introduction and Identification). Make sure to look all around the objects, particularly underneath. Another aid in monitoring are traps which can be found online or at home improvement shops. Moth traps are unlikely to catch every moth in your home, so are not a solution on their own for an infestation. But seeing an uptick of moths in your traps can indicate that there is an infestation brewing. Place traps in dark, secluded places such as the back of the closet and check a few times a month.
Environment
Having moths doesn’t mean that you’re a bad housekeeper, but there are measures that you can take to make your home inhospitable to pests. First off, make it hard for them to get inside! Put screens in your open windows, seal up any holes in your house, and inspect incoming woolen objects for signs of moths.
You can also remove their sources of food. After storing away most of your wool in plastic containers, make sure that any other objects and the rest of your home are clean. In addition to wool, moths are attracted by dust, food, and other detritus. Keep your unstored woolen textiles clean by vacuuming on both sides or washing them as appropriate for their material and strength. When cleaning your home make sure to reach dark, undisturbed areas where pests thrive. Moths won’t magically appear if you put off vacuuming for a week, but if they’re already inside they may be more inclined to multiply.
Conclusion
Moth infestations can be treated by freezing wool textiles in sealed plastic bags for at least two weeks. After freezing, remove any moth debris from the textiles and wash in a manner appropriate for the object. To prevent further pest issues, store wool textiles in sealed plastic containers whenever practical. Monitor your home and objects for signs of moth activity such as frass, casings, or larvae using traps. Make your house unwelcoming to moths by preventing them from entering and cleaning to remove sources of food. I hope that this article was helpful and that everyone’s stashes of yarn remain moth free!
Have you had an experience with a moth infestation? Do you have any questions about pests or textile conservation? Comment below or contact me at spinsterconservation@gmail.com!
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