Moths: The Ultimate Guide

Moths: The Ultimate Guide

When moths get inside your home, they can cause major damage. There are two categories of moths that are household pests, those that infest food and those that infest fabrics. Luckily, there are things that can be done to get rid of moths before they ruin your best sweater or eat your bread and cereal. Prevention and control methods can stop moths in their tracks and keep your home free from these annoying pests.

Moths that Infest Food

One of the most common types of moths that infests food is the Indian meal moth (Plodia interpunctella). These moths are also known as weevil moths, pantry moths, or grain moths. These pests can be found on every continent except Antarctica, but they do best in tropical habitats. In the United States, they are very common in warm areas like Florida. Indian meal moths are 8-10 mm long with a 16-20 mm wingspan. The part of the forewing closest to its body is yellow and gray or white and gray. The far sides of the forewings tend to be reddish-brown in color. A darker band usually separates these differing colors.

 

Adult Indian Meal Moth By Kaldari [Public domain], from Wikimedia Commons

 

Along with Indian meal moths, angoumois grain moths and Mediterranean flour moths are also common in the pantry. All of these moths like to lay eggs on pantry staples like grains, nuts, bread, pasta, cereal, spices, and many other things. When the eggs hatch, the moth larvae (caterpillars) will feed on the grains. It is the larvae of the moths that actually does the most damage. The larvae can chew through paper, cardboard, and plastic, so an infestation can spread to many different food sources.

 

Indian Meal Moth Larvae by Pudding4Brains via Wikimedia Commons

Signs of Food Infestation From Moths

Signs of infestation might include: sightings of adult moths, larvae in packages of grains, or frass (excrement) that looks like colored sand. Indian meal moth larvae will also excrete silk thread/webbing that can be easier to spot than the larvae themselves. Moths can contaminate large quantities of food because they can spread rapidly and may not be noticed for some time.

Pantry Moth Prevention

  • Store all food in sealed containers that are made of glass or thick plastic
  • The fridge and freezer are also safe areas to store food
  • Inspect pantry staples (especially those bought in bulk) before bringing them into your home
  • Use cloves, eucalyptus, bay leaves or other natural ingredients that repel moths
  • Vacuum frequently to get rid of crumbs as well as larvae, eggs, and pupae
  • Keep humidity levels low in the home by using a dehumidifier or air conditioner if needed
  • Seal entry points and hiding places (cracks and crevices) with silicone caulk
  • Make sure the doors and windows have weather stripping
  • Ensure that all screens are in good working order with no tears or holes

Pantry Moth Control Measures

  • Locate infested materials and dispose of it
  • Place food in the freezer or microwave to kill all stages of moths
  • Clean the area with soap and water or vinegar
  • If the vacuum is used, make sure to empty the bag frequently
  • Use pheromone moth traps marked “for pantry moths.”
  • Regular sticky traps may also help control the moth population
  • For major infestations, food grade diatomaceous earth can be used in cracks and crevices, but be careful not to breath it in.

Moths that Infest Clothing

The other major place that moths can be pests in the home is in your closets. Moths will lay eggs on clothing, drapes, carpets, rugs, and other fabrics. When the eggs hatch, the larvae will feast on the materials and will leave holes in them. The common clothes moth (Tineola bisselliella) is a common pest that destroys clothing. This moth is approximately 6-8 mm long with straw colored wings. The wings do not usually have any other markings on them, but the edges of the wings are heavily fringed.

 

Common Clothes Moth By Sarefo [GFDL (http://www.gnu.org/copyleft/fdl.html), CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0/) or CC BY-SA 2.5  (https://creativecommons.org/licenses/by-sa/2.5)], from Wikimedia Commons

 

Another moth that causes a lot of damage in homes is the brown house moth (hofmannophila pseudospretella). The brown house moth is fairly unique because it will infest both the pantry and clothing. The caterpillar of this moth will feed on a variety of organic detritus that ranges from seeds and grains to clothing and fur. Brown house moths are usually 8-14 mm long with a wingspan of up to 26 mm. They are brown with 3-4 darker spots on each wing.

 

Brown House Moth By Svdmolen [GFDL (http://www.gnu.org/copyleft/fdl.html) or CC BY-SA 3.0  (https://creativecommons.org/licenses/by-sa/3.0)], from Wikimedia Commons

Clothing Moth Prevention

  • Inspect used clothing before bringing it into your home
  • Vacuum regularly, especially under furniture, in corners, and in closets
  • Keep humidity levels low by using a dehumidifier or air conditioner
  • Seal entry points and hiding places (cracks and crevices) with silicone caulk
  • Make sure the doors and windows have weather stripping
  • Ensure that all screens are in good working order
  • Use natural repellents in closets like cedar chips, cedar oil sachets, or camphor
  • Make sure that your clothes are clean when they are in your closet
  • If you don’t wear an article of clothing regularly, shake it out once or twice a month
  • Store seasonal clothing or heirlooms in heavy plastic bags or plastic containers

Clothing Moth Control Measures

  • If you have found a moth infestation, wash all fabrics in the area and dry them. The heat will kill all stages of moths.
  • Vacuum the area thoroughly and change the vacuum bag often
  • Clean out cupboards, drawers, suitcases, or other areas that have touched the clothing
  • Use pheromone moth traps labeled for use on clothing moths
  • Regular sticky traps can also be used to help monitor the population
  • Insecticidal dust can be used for major infestations. Apply this dust according to label directions in cracks, crevices, wall voids, etc.
  • For better control, microencapsulated products that are approved for indoor use can be used, but are not usually needed.

Moths can be problematic for homeowners across the country, especially those that live in more humid areas. Don’t let an infestation contaminate your pantry and ruin your clothes. Instead, stay on top of moth problems by using the prevention and control tips provided. 

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