What do warehouse moths look like, are they harmful and how do you get rid of them? Discover some of the natural ways of eliminating warehouse moths from your home.
Considering they are commonly known as warehouse moths, cocoa moths or tobacco moths, it is not hard to guess what kinds of things Ephestia elutella like to infest. Warehouse moth larvae contaminate a wide range of products, from cocoa beans, chocolate, cereals, nuts and dried fruit to tobacco, straw and hay. They are capable of causing extensive damage in our kitchens and major problems in warehouses and grain storages. Read on to find out how to identify warehouse moths in your home and how to get rid of them naturally and effectively.
Warehouse moths: life cycle and origin
Warehouse moths originate from Central Europe. While they are sometimes found in nature, you are more likely to come across them indoors as they have adapted well to humans and the way we store food. Since many products are traded across the globe, warehouse moths eventually made their way to Southern Europe, North America and have now infested the whole world. In the UK, the flight period of adult warehouse moths is from May to October. During this time, they lay their eggs on or near potential food sources such as grain silos, tea bags, chocolate or porridge oats. The larvae then hatch in food paradise and grow into adult moths within 40 to 100 days, depending on the temperature and humidity.
How to identify warehouse moths
As the adult moths are not always noticeable, the best way to spot a moth infestation is by looking out for the larvae and the silk webs they leave behind in products.
Moth traps such as our Plantura Pantry Moth Traps are useful for detecting a moth infestation at an early stage. The traps contain pheromones, which are chemicals normally emitted by females to attract a mate. Pheromones are used to lure in the male moths, which then stick to the trap. In this way, moth traps are good for detecting the presence of pantry moths, enabling you to act quickly. However, since there is no guarantee that pheromone traps will catch every male and as they have no effect on female moths or larvae, moth traps are only meant for detecting and monitoring moth infestations rather than eliminating them entirely.
What do warehouse moths look like?
The adult warehouse moth is about one centimetre in length at rest and up to two centimetres when its wings are spread out. Its forewings are grey-brown in colour, slightly shiny and banded with darker colours, whereas its hindwings are lighter, appearing almost silver, with a fringe of hair. The larvae, usually found in stored food, are similar to caterpillars in shape and grow up to 15 mm long. They have a dark head and, depending on their diet, are white to yellow in colour. Unfortunately, these do not turn into beautiful colourful butterflies.
Identifying moth damage
While adult warehouse moths and the larvae are not always easy to spot, they are noticeable because of the traces they leave behind in infested products. Tell-tale signs of a moth infestation include damaged grains and solid lumps within flours and tea bags. The silk webs they leave behind are similar to those of the Mediterranean flour moth (Ephestia kuehniella), which can make differentiating between these two types of moth a little tricky. Luckily, that is not a problem as the methods for controlling them are the same. Regardless of moth type, it is important to dispose of infested items immediately.
Natural warehouse moth control
There are a number of conventional methods of getting rid of a moth infestation, the most popular being insecticides. These usually come as sprays which kill the moths. However, these kinds of sprays are usually full of chemicals that are neither good for the environment nor for our health.
A more environmentally-friendly way of getting rid of moths is by using ichneumon wasps. These tiny useful insects are employed to control pest populations and are a safe and efficient means of killing moths. Still, it is important to dispose of all infested food products beforehand as the webs and larval excrement are a health hazard.
Since ichneumon wasps are living moth killers and have a short lifespan, they are not usually available to buy at shops. Our Plantura Mini-wasps against Pantry Moths are available to purchase at our online shop and are delivered straight to your door. They come in carded dispensers, ready to be placed at the site of infestation. The number of cards you require depends on the size of your kitchen or pantry. We recommend using four cards for a standard-sized kitchen. It is best to use the cards as soon as they arrive because it does not take long for the beneficial wasps to hatch and get to work. The ichneumon wasps tackle moth infestations by seeking out the moth eggs and parasitising them. To ensure that all the moths are gone and to completely break their life cycle, you will need to introduce the wasp cards a total of four times. This is why you will receive a total of four fresh sets of parasitic wasp cards at fortnightly intervals when you order our mini-wasps.
- Effective & chemical-free biological control for pantry moths
- 1 one-time payment for 4 separate lots of mini-wasp cards delivered at 2 week intervals
- Highest quality parasitic wasps - not harmful to humans or pets
Ichneumon wasps are very discreet little helpers. They are tiny creatures, hardly visible to the naked eye, and cause no disturbance whatsoever. They can neither sting nor fly and are also completely harmless to humans and warm-blooded animals. As they are not able to reproduce without moth eggs, they only stick around until their mission is complete.
Summary – How to eliminate warehouse moths with ichneumon wasps
- Order our Plantura Mini-wasps against Pantry Moths (how many cards you need depends on the size of your kitchen or pantry: 1 card covers an area of 1 m2)
- Place the cards at the site of infestation and leave them there for 2 weeks
- You will receive 3 follow-up deliveries (no extra delivery charges) of fresh ichneumon wasps at 2 week intervals
- Repeat the process after each delivery
Tip: Continuing to use pheromone traps such as our Plantura Pantry Moth Traps for the male moths is not necessarily a problem, as they do not disturb the parasitic wasps. Just make sure not to place them immediately next to the wasp cards, as the wasps might get stuck to the traps accidentally. Although pheromone traps cannot entirely eliminate a moth infestation, they are great for monitoring moth numbers.
Warehouse moth prevention
Now that you have a pest-free home, it is time to prevent further infestations in the future. The best way to do this is by storing food in airtight plastic or glass containers. The thin plastic and paper packaging our food normally comes in is not suitable for storage as it does not offer enough protection against moths – the caterpillar-like larvae will simply munch their way through it. It is best to transfer store-bought products into a different container as soon as you get home, as moths may have already made their way into these products.
If pantry moths have become a regular issue in your home, it may be worthwhile monitoring the situation a bit more closely. Pheromone traps such as our Plantura Pantry Moth Traps will help you do just that. However, bear in mind that the pheromones in the traps wear off over time, so you will need to replace the traps approximately every six weeks.
Tip: If you are using glass containers with screw-on lids, make sure they have a seal to prevent the tiny moth larvae from sneaking their way in.
Summary: How to prevent warehouse moth infestations
- Store food in airtight, sealed glass or plastic containers
- Check even freshly bought items
- Hoover regularly
- Set up pheromone traps for monitoring moth infestations
Ichneumon wasps have proven to be an effective method for combatting many pests. For more information about these little helpers, see our article on ichneumon wasps.