The Life Cycle Of Clothes Moths

There are two common types of wool/natural fiber eating moths, Webbing cloth moths and Case-making cloth moths. Case-making moths are very common in Victoria, BC. Luv-A-Rug has treated and cleaned many wool rugs that had become victims of the case-making moth.

Differences between the two are as follows:

Webbing cloth moths are golden in colour and are weak fliers; they tend to stay close to a food source. The larvae make a silk like webbing on the fiber and they feed under it. The damage that they leave behind is more evident than the case-making because as they move along the rug they leave behind webbing.

Case-making cloth moths are a more brownish golden and have a black dot on their wings. The larvae make a silken tube that is open at both ends for feeding and moving. The tube hardens when the larvae enter the pupate stage and is abandoned after it hatches into an adult. Looks like flat pieces of rice, usually in the colour of wool that they were eating.

A moth's life cycle begins as the female moth finds a warm, dark, dry, and undisturbed food source for her eggs. The eggs are a translucent white and are attached to the wool fiber so that they will survive any movement that may occur.

The female moth may lay up to 50 eggs over a couple of weeks, after which she dies. Whereas the male moth will to breed for about a month and then he dies.

The eggs hatch within two weeks, depending on environment temperature. The larvae are white and worm like. The larvae are what eat away at your rug. As soon as they hatch they start feeding. The larvae do not drink liquid and therefore prefer wool that is soiled because it contains the essential vitamins and minerals it needs to survive.

The length of the larvae stage greatly depends on the abundance of food and environment temperature; anywhere from 30 days to 18 months. When it is ready to pupate it makes a hard cocoon and depending, again, on environment temperature, pupation may last one to four weeks. The adult moth emerges and the life cycle begins anew.

If you are like me reading this makes you a little apprehensive and you want to clean and sanitize your entire house. That is a good response because doing a thorough cleaning is the best way to prevent an infestation.

The places moths enjoy are wool rugs that are under furniture, storage areas where woolens and furs are kept, along baseboard and cracks where hair and dust accumulate, air vents and ducts. They love areas where there is an abundance of wool and that is undisturbed.

The best defensive tool to use against moths is the vacuum cleaner. Vacuuming the entire rug, front and back, at least once a month is the best way to have your rugs be undesirable to moths. Check stored woolens and furs in the summertime, catching an infestation early can save your belongings. Dry clean or launder wool and fur items before storing. Storing them in tightly sealed containers helps against moths making them their home. If possible put your furs into cold storage, if available, since moths do not like the cold.

Moths also live in bird, rodent and abandoned wasp nests. Eliminating nest from outside of your home and the attic is another way of preventing an infestation. Moths stay close to the food source, when the population becomes greater than the food source they look for another one, such as your rugs. Getting your air ducts professionally cleaned annually also takes away another of their breeding areas. The dust contained in the ducts may contain wool fibers and they are undisturbed for long periods of time.

Checking for a possible moth infestation is a hands and knees operation. Carefully look at the front and back of the rug for live larva. Turn your rug upside down and vacuum it with a rotating brush, then inspect the dirt for small sand like black round pelleted excrement. Moth eggs are harder to spot since they are attached to the wool fibers. If the larva has already started eating the wool rug you will see missing fibers in patches, empty casings that look like dead larva, webbing or live larva. When vacuuming after an infestation has occurred, dispose of vacuum bag because the bag of dirt is a moth larva's buffet. Even if it looks like the larvae are dead and gone there may still be live eggs. Always get your rug professionally taken care of if any moth damage is found.

If eggs and/or live larvae are found immediately roll the rug up, if possible wrap it in plastic, remove it from your home and get it professionally taken care of. If the infestation is bigger than just a few items you may need the professional assistance of pest control. When you see the flying moths it is just the tip of the moth iceberg, it is not what you see that does the damage, but what you don't see.

The method's used to deal with an infestation range from completely non toxic, freezing, to extremely toxic, insecticides.

When an artifact goes to a museum to be put on display it first has to be cleaned and preserved. The make sure there are no dormant and unwanted critters most artifacts go through a freezing to kill and eggs, larva and bugs.

You too can use freezing to rid your wool clothing and small items or moths. To freeze an item, such as a sweater, the optimal freezer temperature should be less than -17.7 degrees Celsius (0 degrees F). Put the item into a plastic bag and squeeze out the air, then seal it tightly. The item needs to be room temperature or warmer before entering the freezer because it is the extreme temperature change that kills the moth eggs or larva. The eggs or larva can become resistant to freezing if they are cooled too slowly. Freeze the item for one week, remove it from the freezer for a couple of days to bring it back up to room temperature. DO NOT OPEN OR REMOVE ITEM FROM BAG. After a few days return item to freezer again for another week.

After the item the second freezing it should be cleaned, ensuring that no eggs or larva are left on the item.

Another safe way of getting rid of moths is with a moth pheromone trap. It is a triangle paper trap with a sticky substance on the inside to which a pheromone is attached. The male clothes moths are attracted to the pheromone and fly into the trap. To get a pheromone trap the type of moth needs to be identified by a pest control professional. Luv-A-Rug has used Olympic Pest Control (250-360-2847). They trap a moth and take it back to their lab and match it to the right pheromone. Getting the right pheromone is the key to eliminating the moths. The traps are used in conjunction with a thorough cleaning of your home: cleaning not done by the pest control professional. The traps only get rid of the adult male moths not the eggs or larvae.

Moth balls/flakes/crystals are an effective repellent when used correctly. However, they are a toxic and need to be used as per package instructions and with caution.

Key points to know about moth balls/flakes/crystals:

There are two main ingredients- Naphthalene found in moth balls and sometimes flakes and
Para dichlorobenzene or PDB found in moth crystals.

Either product must be used in a sealed air-tight container so that it can effectively build up a high concentration of gases.

The ideal temperature for PDB to turn into a gas is above 10 degrees Celsius (50 degrees F).

PDB does react and melt plastic containers containing polystyrene and may harm plastic buttons and decorative embellishments on the garments.

Naphthalene should not touch the items directly as they can cause discolourations.

Naphthalene can corrode some metals.

When storing either moth repellent, it should be doubled bagged and kept in a cool well ventilated area, such as garage.

The moth repellent should be above the items being protected because the gases produced are heavier than air.

When removing item from storage, it should be done outside because the gases produced are toxic and shouldn't be inhaled.

Moth repellents are considered a Household Hazardous Waste and shouldn't be thrown in the trash or down the drain. They need to be disposed of at a Hazardous Waste Collection site.

Always air out the items after storage and have them cleaned to eliminate the gases that they have absorbed.

After reading many websites and articles the question about how effective cedar chests and cedar chips are for moth repellent is still unanswered. The two main points against cedar chests are that they are not air tight and the cedar oils dissipate. Sanding the cedar chest every 1or 2 years exposes more oils though. Cedar is 100% natural and non-toxic, but may not be the most effective against repelling moths.

From all the research I have done over the last couple of months to write this article on moths, the best defense against an infestation is good housekeeping. We often forget to clean under things because we don't use that space, but moths and other insects do. Checking stored woolens every few months and keeping them in air tight containers is another good tip I have found. When bringing items from a tropical country get them cleaned before use and storage, is another way to prevent unwanted guests.