Advice | You have moths. Here’s how to get rid of it.
There’s an easier way to determine which category of moth you’re dealing with: If you see moths flying around while you’re out and about, it’s likely pantry pests. Closet moths shy away from light and mainly fly at night. In addition, pantry moths are more likely to fly around simply because their life cycles are relatively short – about 25 days from egg to adult. Depending on the temperature, hive moths can take a month to two years to reach the flight stage.
The most common pantry moths are Indian meal moths. The adults have wings that are brown and tan, with lines separating the colors. The caterpillars, which are whitish, grow to about ½ inch in length, creating silk bands on food. They are not picky eaters; they can contaminate flour, grains, milk powder, dried dog food, dried fruit (think raisins), and birdseed. The caterpillars of another type, Angoumois corn moths, develop and feed in whole grains of corn or maize, or in seeds.
However, there is no need to identify the type of pantry moth, as the solution is the same in all cases – and they are not pesticides. You need to find all the food that has become contaminated and either throw it away or at least put it in containers that prevent insects from getting in or out. And wipe the cabinets and vacuum crevices to remove any cocoons.
You don’t need to spend a lot of money on this cleanup. Instead of buying matching containers, you can reuse glass jars and takeout containers with tight-fitting lids. And while food with small white caterpillars and Velcro may not look appealing, it is safe to eat because pantry moths don’t spread disease. However, most people just throw the food away. It should be in a trash can outside your home or in a food waste bin, if your community provides it.
Keeping all of your stored food in pest-resistant containers is no guarantee you’ll never have a pantry moth problem; food you buy in a supermarket can be contaminated when you take it home. But the containers will herd a new batch of caterpillars so they can’t lay eggs in other food.
If the moths continue to appear once your dried food is in pest-proof containers, you may see adults emerging from cocoons spun by caterpillars that left the contaminated food before you clean up. Caterpillars of Indian mealy moths often crawl up to ceilings or walls before cocooning, and it can take several weeks for the last of these cocoons to release the moths that have formed inside them.
But if the problem persists for more than a few weeks, you may have missed a spot where the caterpillars are still feeding. Ornamental corn, dried flowers and plants, chocolate and even potpourri can be suitable habitats. So are unopened boxes of cake mix or other packaged foods. Check boxes for signs of webbing or small holes that caterpillars may have chewed on; if you’re not sure and don’t want to throw the boxes away, put them in the freezer. At least four days at zero degrees Fahrenheit will kill both eggs and caterpillars.
Pantry infestations are annoying, but controlling closet moths can be even more painful. These pests, also known as carpet moths and textile moths, can have spread throughout your home, causing costly damage before you even knew they were there. The caterpillars eat animal fiber, i.e. wool, mohair, cashmere, leather, fur and feathers. That includes clothing, carpets, stuffed animal heads, family heirlooms, and sometimes even abandoned bird nests in attics. Items that have been stored for a long time and carpet that is rarely vacuumed because it is under heavy furniture are most likely to have holes or bald spots.
There are two types of closet moths: closet moths and webbing clothes moths. A caterpillar with a housing makes an open-ended fiber tube about ½ inch long to shelter in while it feeds. Pipes can often be seen on carpet or clothing. A webbing caterpillar creates a patch of tissue over the surface and hides beneath it as it dines.
Pesticides are generally not very helpful in controlling a moth problem as there is no way to spray just the caterpillars; you would also get the pesticide on your clothes, carpet and other valuables. Instead, you should remove and dispose of or handle any item that is contaminated or prone to contamination.
The old-fashioned treatment was to hang stuff outside and hit it with a stick to make the eggs and caterpillars fall off. Today, dry cleaning, washing in warm water (at least 120 degrees), heating in a dryer, freezing for about three days, or vacuuming carefully can kill or remove both eggs and caterpillars. Be sure to wash or dry clean any clothes you’ve been wearing, as clothes moths are attracted to fibers with body oils or spilled food.
Before you put things back into cabinets, vacuum the space thoroughly, especially along carpet edges, baseboards, and crevices. Consider storing items that you don’t use often in plastic containers with tight-fitting lids or in compression bags.
Because it is so difficult to spot a moth infestation before significant damage has been done, you may want to invest in pheromone traps, which can serve as an early warning system. The traps use a female’s scent to attract males. Only males are likely to end up on the sticky trail of the trap, but fewer males means fewer mating partners for females. Some traps work with a specific type of moth. For example, the Raid Clothes Moth Trap ($48.92 for 12 at Home Depot) is listed for attracting webbing moths.
Do you have a problem in your home? Send questions to localliving@washpost.com. Put “How To” in the subject line, tell us where you live and try to add a photo.