Identification

Various beetles and moths are grouped as Stored Product Pests primarily because of their feeding and nesting habits in pantry items. These include Flour Beetles, Sawtoothed Grain Beetles, Dermestid Beetles, Granary and Rice Weevils, and Spider Beetles. Of these, Drugstore and Cigarette Beetles as well as Indian Meal Moths are most prevalent in the Pacific Northwest.

Drugstore Beetles are about a tenth of an inch long and reddish-brown with an elongated shape. The head is deflexed, and the tips of the antennae have three enlarged segments. Faint lines run lengthwise on the beetles’ wing covers.

Cigarette Beetles are about an eighth of an inch long, yellowish to reddish-brown and are oval-shaped. The head is bent downward sharply, nearly at right angles, giving the beetle a humpbacked appearance. Wing covers are smooth, and the antennae segments are uniform and saw-like.

Eggs of both beetle species are pearly white and not easily seen with the naked eye. When fully grown, the larvae are crescent-shaped and about three-sixteenths of an inch long. Cigarette Beetle larvae are one-sixth of an inch long, creamy white and covered with long yellowish-brown hairs. They also have brown heads and legs. Drugstore Beetle larvae are similar but do not have a fuzzy appearance.

Indian Meal Moths have distinctive wing markings and are nearly half an inch long. The base of the forewing is pale gray, and the outer two-thirds are reddish-brown with a coppery luster. The larvae are generally beige with shades of yellow, pin, brown, or green depending upon its food source.

Education

The appearance of small beetles sprawled over counter tops, caterpillars crawling up walls, or moths flying across rooms are usually an indication of a Stored Product Pest infestation. Upon closer inspection, these insects are also found in opened/unopened packages and food containers or in the cracks and crevices of cabinets and cupboards. These pests are often brought into the home via infested food products. Once inside, they begin multiplying and eventually spread to other store foods. While adults are often seen, it is the larvae that cause the most damage.

True to their name, Drugstore Beetles feed on a variety of pharmaceutical products including laxative teas and strychnine. In the home, they may also feed on:

  • Almonds
  • Peanuts
  • Paprika and red pepper
  • Alfalfa meal
  • Cornmeal, flour, and wheat
  • Dry dog and cat food
  • Birdseed
  • Coffee beans
  • Powdered milk
  • Books and manuscripts
  • Dried flowers
  • Certain fillers
  • Fabric coverings

A female lays her eggs on food items. Eggs then hatch within a few days, but the larval period may last four to five months. It takes 12-18 days for pupae to develop into adults. One generation is produced each year in cooler climates.

Cigarette Beetles prefer to feed on dried tobacco, but will also eat:

  • Spices
  • Biscuits
  • Beans
  • Dates
  • Dried fruits
  • Cottonseed meal
  • Peanuts
  • Yeast
  • Dried fish
  • Seeds
  • Leather

They may also damage the leaves and bindings of books when feeding on paste.

A female will lay about 30 eggs over a period of three weeks. The eggs hatch in six to 10 days. The larval stage lasts five to 10 weeks and the pupal period lasts two to three weeks. Each year, three to six generations may be produced.

Pests found in flour mills and food storage areas are called Flour Beetles. They are reddish brown and one-seventh of an inch long. They also have a smooth thorax. They feed on a variety of foods, including:

  • Flour
  • Cracked grains
  • Cake mixes
  • Bean
  • Peas
  • Dried fruits and nuts
  • Chocolate
  • Spices and tobacco

They do not feed on whole, undamaged grains. Heavily infested food products have a foul odor.

Females lay eggs either on containers or in the food itself. The eggs hatch in five to 12 days. Larvae are cylindrical, yellowish-white and about a quarter of an inch long. Pupation occurs near the surface of the food mass. Five generations may be produced each year, depending upon temperatures.

Sawtoothed Grain Beetles are perhaps the most commonly found pantry pest. Adults are nearly a quarter of an inch long, slender, flat and brownish red. Their sleek bodies enable them to penetrate the narrow cracks and crevices of poorly sealed packages. They also have six saw-like teeth on either side of the thorax, which is located behind the head. While they may not feed on undamaged, whole grains, they do enjoy cereals, bread, dried fruit, nuts, sugar, macaroni, and seeds.

The female lays anywhere from 45 to 287 white, shiny eggs into food. The eggs hatch in three to five days. Larvae are yellowish-white and less than a quarter of an inch long. Pupation occurs within the food material. The complete life cycle from egg to adult may occur in 40-60 days. Six generations may be produced each year.

Several species of Dermestid Beetles feed on dried meats, cheese, dead insects, hides, and woolens. They may sometimes feed on stored foods including grains, seeds, and dried fruit. Adult beetles may be oval or round, mottled gray to black and are about three-eighths of an inch long. The larvae are similar in size but banded with dark, long hairs. Six generations may be produced each year.

Granary and Rice Weevils have snouts projecting from their heads and distinct ridges on their wing covers. Adult weevils are dark brown and nearly one-sixth of an inch long. They generally damage whole grains or seeds, but are sometimes found feeding on nuts and beans.

Females lay eggs on seeds, kernels, or other similar foods. Their eggs hatch in three to seven days. Larvae are white, legless and usually feed on the kernel of seeds while inside. Pupation then occurs within the hollowed-out kernels or seeds. Adults emerge in about five to 16 days later. Most weevils produce three to five generations each year.

Spider Beetles have a compact body shape. Adults vary in size from an eighth to a quarter of an inch long. They are usually oval-shaped and reddish-brown to black. The head is partially visible above the thorax. With their six long legs and long antennae, they often resemble the eight legs of a spider. They feed on grains, seeds, cereals, dried fruits, meats, wool, and hair.

Females lay eggs within their food mass. The eggs hatch in about eight to 12 days. Mature larvae have a cream to tan color and usually curl their bodies when disturbed. Most Spider Beetles have two to three generations each year. Adults live less than two weeks, are non-feeding and chiefly fly at night.

Adult Indian Meal Moths live less than two weeks, fly at night, and are non-feeding. It is their larvae that cause the most grief among homeowners. When fully developed, Indian Meal Moth larvae frequently wander in search of a place to pupate and as such, may be found on ceilings, walls, and countertops. Occasionally, the larvae will suspend from the ceiling from a single, silken thread.

While coarse grades of flour are preferred, the larvae are often found feeding on whole grains, cereal, dried fruits, nuts, seeds, chocolate, powdered milk, bird seed, and dog food. Foods infested with larvae will have a silk webbing present, especially near the food source, as well as cast skins and frass (fecal pellets). These moths produce about four to eight generations per year.

Customer Preparation

Inside Only:

  • Remove everything out of the kitchen cabinet or pantry where there is activity
  • Make every effort to find the food source
  • Remove infested food or non-food items.

Customer Expectations from Treatment

Our products will kill the Stored Product Pests on contact and act as a repellant by leaving a long-term residue that outlasts the lifecycle of the bugs. Expect a steady decline of pests and an occasional sighting thereafter. However, if hundreds of beetles appear from the cupboards, it may be an indication of a possible rodent infestation.