Latin: Ephestia Kuehniella
This flour moth has caused a great deal of damage since it was found in a batch of wheat from America in 1877. The flour moth originates from somewhere between Asia and the Middle East, and it has since invaded mills, grain warehouses, and bakeries throughout Europe and North America.
Flour moths is rarely a problem in private homes, but it can nonetheless be a problem in certain situations. Most often, the moths and moth larvae found in private homes are instead the Indianmeal moth. Flour moth is more often a problem in the industry.
Appearance
The flour moth has an elongated shape with narrow wings. Its body is about 10-12mm long, and a wingspan of 20-22 mm. Compared to other species of moths, flour moth may look a little thin when resting. Their wings are narrow, and they lay them flat over their backs when they are not flying. The flour moth can be recognized by its colors on the wings. The forewings have a lead gray color with a pattern. The pattern is zigzag with transverse lines and dots. The hind wings are a lighter shade of gray with fringes on the trailing edge.
A larva from a flour moth is typically between 15 and 19 mm, so relatively short compared to the adult moth. An interesting thing about the larvae is that they can have different colors. They are either white, pink, or light green as larvae. However they all get the same color when they are fully grown flour moths.
Biology and behavior
Adult moths are particularly active at dawn and around dusk. Here they fly around looking for a mate or, if they have already found a mate, to lay eggs. Flour moth can mate as soon as they hatch. From mating, it only takes a few hours for the female to lay her eggs. A female can in average lay 200 eggs, which then take 1-2 weeks to hatch.
The eggs are often laid in flour, from which the moth got its name. The hatched larvae immediately begin to eat the flour. They can also eat grains, seeds, brants, and other dry goods, depending on where their eggs have been laid. Then the larvae begin to spin silk threads. The flour moth larvae have a sticky web. It is this web that creates difficulties for the industry. The larva’s sticky silk attracts flour, dust, and the larva’s own excrement. This can give small pockets of extremely unsightly odor and contaminated flour.
Both adult flour moth and their larvae will try to create a dark habitat or search for dark corners of wherever they live. Therefore, the moth larva is rarely seen, as it simply digs deep into the stock of flour until it is fully grown. As a full-grown larva, it begins to pupate. The pupate period of the flour moth lasts 17-20 days, after which the adult flour moth immediately looks for a mate.
Damage
As mentioned, it is especially the larva that cause damage in stocks of flour and similar goods. The moth is of course also a problem, as it is the adult flour moth that lays the eggs in the flour.
Flour moths can be difficult to control, as most insecticides are toxic to humans. Flour moths are also difficult to detect before the accidents are massive. However, private individuals can usually be calm; industrialists, make sure that the products from their inventories is safe.
Prevention and control
Flour moth is mostly seen in private households when they have been brought into the home in bag of infected flour or grain. It will usually only be a single larva which will not develop into more. If you want to be on the safe side, you should immediately discharge the infected flour. You can also contact the manufacturer and/or dealer to tell them about the problem. In rare cases, whole infestations can occur in the kitchen. All items that have been attacked should be discarded, but slightly damaged items can be heated through for an hour at 55 degrees to prevent further egg laying.
Remember to clean kitchen cabinets, drawers, cracks and crevices after an attack, as eggs can be hidden here. Also, store flour and other foods in air-tight containers so that the moth cannot reach the food.
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