AMERICAN SPIDER BEETLE Mezium americanum

Size:

About 1/8 of an inch

Color:

The abdomen is shiny reddish brown. The head, thorax, legs and antennae are cream colored.

Behavior:

About 30 species of spider beetles worldwide may be pests of food products. Only a few of these are found in the United States and Canada and the shiny spider beetle is one of those most commonly encountered. Spider beetles are mainly scavengers on plant and animal substances and are usually seen in grains infested by some other stored product beetle. They often feed on parts of dead insects within the food product. Spider beetles contaminate food products with body parts, feces and pupal cases. These beetles prefer the dark and are most active at night or continually in darkened areas. Spider beetles harbor during daylight hours inside crevices, between food packaging and other darkened areas. Activity is greatest where cooler temperatures are found. For example, activity is seen more toward the outside of an infested stack of food products rather than the inside. Spider beetle larvae will attack almost any dry food and will gnaw small holes in food packaging. Heavily infested bags of food items may be riddled with such exit holes and also become covered by the silken pupal cocoons spun by the larvae. Only a few species of spider beetles can fly and the American spider is not one of these. Spider beetles often feign death when disturbed by drawing their legs up to their bodies.
The American spider beetle is generally of minor importance. It feeds on both animal and vegetable products, including melon seeds, mixed feed, grain, tobacco, cayenne pepper and woolen carpeting. It is most commonly seen in homes but has also been found in warehouses and flour mills. These beetles are also known to breed in large accumulations of pet, bird, bat and rodent feces often found in bird or bat roosts.

The control of any stored product pest involves many steps, primary of which is discovery of infested food items or other sources of infestation (e.g., food spillage accumulation). All dried food products need to be inspected for signs of infestation. Areas where rodent, bird or bat feces may have accumulated within a structure also need to be checked. A pest management professional can be helpful in finding difficult infestation sources. Consider the following to prevent an infestation:
The following precautions should be taken to prevent accidental stings:
• Discard infested foods in outdoor trash. Infested decorations (flowers, wreaths, etc.) should also be discarded. Clean and remove infested accumulations of animal feces using accepted safety precautions. Bird and bat feces are known sources of many pathogenic organisms including histoplasmosis and cyrptococcosis. Where deer mice may be present in a building, the mouse feces have been known to harbor infectious strains of hantavirus. A company qualified in remediation of animal feces accumulation should be consulted for such situations.
• Clean cabinets and shelves where infested foods are stored by vacuuming and by using soap and water. o Store all dried food goods, including dried pet foods and birdseed, in a glass or plastic container with a tight lid. If beetles are in that food product then the infestation will be contained and not spread to other foods.
• Consume older food products prior to newer purchases of the same food. Products purchased in larger quantities (e.g., from a wholesale food warehouse) are more likely to become an infestation source if these are stored for long periods of time – especially if they are not stored in containers with tight-fitting lids.

BEAN WEEVIL Acanthoscelides obtectus

Size:

1/6 of an inch

Color:

Olive brown with brown or gray spots on wing covers. Its thorax is covered with fine yellow-orange hairs.

Behavior:

The female bean weevil deposits her eggs on bean pods in the field or on whole beans in storage. Each female lays up to 60 eggs in her lifetime and numerous whitish eggs can be seen on a single bean. Bean weevils are internal feeders so the tiny, grub-like larvae bore their way into the bean. Several larvae may feed inside each bean and a considerable portion of the bean’s interior is consumed. It is the larvae that do the damage. Adults do not feed. Upon maturity, the larvae pupate near the surface of the bean and then emerge from the bean, leaving numerous holes in the bean. The entire life cycle can last from 21 days or as long as 80 days. Populations of bean weevils develop quickly in stored beans where suddenly hundreds or thousands of weevils are seen crawling or flying in infested rooms. The first indication of an infestation is often the presence of numerous flying weevils. A bag, box or storage bin of beans may be so infested that weevils are forced to leave the container in search of fresh beans on which to lay their eggs. Bean weevils “play dead” when disturbed and may take up to five minutes to resume movement.
Bean weevils infest only whole beans and other legumes and do not infest other types of stored foods such as cereals or whole grains.

The control of any stored product pest involves many steps, primary of which is discovery of infested food items or other sources of infestation (e.g., food spillage accumulation). When bean weevils are present, all items containing or made of whole beans need to be examined. Usually, bagged beans in the pantry are the source but some decorative items are made of or contain whole beans so such items should not be overlooked. Also consider the following to prevent an infestation: o Discard infested foods in outdoor trash. Infested decorations (flowers, wreaths, etc.) should also be discarded. o Freeze suspect foods at zero degrees Fahrenheit for six days. o Clean cabinets and shelves where infested foods are stored by vacuuming and by using soap and water. o Store all dried food goods, including dried pet foods and birdseed, in a glass or plastic container with a tight lid. If beetles are in that food product then the infestation will be contained and not spread to other foods.

CIGARETTE BEETLE Lasioderma serricorne

Size:

About 1/10 of an inch

Color:

Shiny brown

Behavior:

The female cigarette beetle lays 30-40 eggs over a period of weeks in a stored tobacco or dried food product. The eggs hatch within six to 10 days and the larvae begin crawling throughout the food source while feeding. The larvae prefer the dark and take about 5 to 10 weeks before pupating. The entire life cycle takes up to 90 days to complete with up to six overlapping generations occurring each year in warm climates. This shorter life cycle permits a faster development of cigarette beetle populations, facilitating the spread of cigarette beetles to uninfested food products stored nearby. This beetle is an external feeder, meaning the larvae develop outside of whole seeds. It is most commonly associated with processed foods of all kinds. Adult beetles are strong fliers most commonly seen in low light conditions. This beetle can be found throughout the year, but is especially common during the fall and winter.
As its name implies, the cigarette beetle is a pest of dried tobacco in tobacco warehouses and processing facilities. Interestingly, this beetle is not commonly found infesting stored cigarettes or cigars in stores or homes. It will infest a wide variety of food products and is common in pet food, cereals, nuts, dried peppers, spices, raisins, seeds and dried straw flours. Cigarette beetle larvae have also been found to feed on the stuffing inside upholstered furniture. The cigarette beetle is also a major pest in museums, where it attacks botany displays and other artifacts of vegetative origin.

The control of any stored product pest involves many steps, primary of which is discovery of infested food items or other sources of infestation (e.g., food spillage accumulation). All dried food products need to be inspected for signs of infestation, including cereals, packaged dried foods (e.g., food bars and chocolate) and pet foods. Cigarette beetles have also been found infesting dried flowers, potpourri and dried peppers used as decorations. Keep in mind that infested items may not always be stored in the kitchen. Spices, potpourri and decorations made of vegetative products may be stored in any room of a house. Infestations have also been traced to caches of nuts and seeds accumulated by squirrels or rodents within attics, walls and chimneys. A pest management professional can be helpful in finding difficult infestation sources. Also consider the following to prevent an infestation:

• Discard infested foods in outdoor trash. Infested decorations (flowers, wreaths, etc.) should also be discarded.
• Freeze suspect foods at zero degrees Fahrenheit for six days.
• Clean cabinets and shelves where infested foods are stored by vacuuming and by using soap and water.
• Store all dried food goods, including dried pet foods and birdseed, in a glass or plastic container with a tight lid. If beetles are in that food product then the infestation will be contained and not spread to other foods.
• Consider storing cereals and similar foods in the refrigerator to limit stored product pest problems.
• Consume older food products prior to newer purchases of the same food. Products purchased in larger quantities (e.g., from a wholesale food warehouse) are more likely to become an infestation source if these are stored for long periods of time – especially if they are not stored in containers with tight-fitting lids.

COWPEA WEEVIL Callosobruchus maculates

Size:

1/6 of an inch

Color:

Brownish in color; some specimens may appear greenish brown in color.

Behavior:

Cowpea weevils are comprised of several species and are more common in the southern United States. The life cycle is similar to that of bean weevils. Like bean weevils, the cowpea weevil is an internal feeder. The female deposits her eggs on the outside of the bean. The larvae bore into the bean and several larvae infest the same bean. Upon maturity, the larvae pupate near the surface of the bean and then emerge from the bean leaving numerous holes in the bean. Huge populations can quickly develop especially under ideal conditions of 90ºF and 90% humidity. The first indication of an infestation is often the presence of numerous flying weevils. Usually, the infested bag, box or storage bin of cowpeas or other beans is so infested that weevils are forced to leave the container in search of fresh beans on which to lay their eggs. Cowpea weevils “play dead” when disturbed and may take up to five minutes to resume movement.

DRIED FRUIT BEETLE Carpophilus hemipterus

Size:

1/8 of an inch

Color:

Brown with yellow spots on wing covers

Behavior:

The dried fruit beetle belongs to the family Nitidulidae, which contains the sap beetle. It is the most important pest species of this group. These beetles are strong fliers and constantly search for ripe or fermenting fruit. More than 1,000 tiny, white eggs may be deposited by the female on ripening fruit on trees or fruit on trays drying in the open. Infestations, therefore, often begin prior to the fruit being processed or stored in packing sheds. Another source of dried fruit beetles and other sap beetles are refuse dumps where fruit byproducts are disposed. Infestations never occur on whole sound fruits. Fruit is attacked before it is completely dry and usually, only cracked or fermenting fruit is infested. The larvae are white to amber in color and grow to about ¼ inch in length. Development to the pupal stage takes two to four weeks during which the larvae undergo several molts. Each molt results in a cast skin left behind and, together with fecal droppings, infested fruit can be rendered unpalatable by just a few larvae. The life cycle can be completed in a minimum of 15 days during hot weather but may take months during colder months. During their activities, dried fruit beetles may carry yeast cells, fungi and bacteria into the fruit causing it to sour and spoil.
The dried fruit beetle is found worldwide, especially in regions where fruits are grown, processed and stored. It is a prominent pest in California. This beetle attacks both fresh, ripened fruit and dried fruits prior to storage and packaging. This beetle is especially fond of figs and dates and is a common pest of raisins.

The control of any stored product pest involves many steps, primary of which is discovery of infested food items or other sources of infestation (e.g., food spillage accumulation). This beetle will only be associated with moist, fermenting fruits so it is an uncommon pest in homes. Consider the following to prevent an infestation:

• Discard infested foods in outdoor trash. Infested decorations (flowers, wreaths, etc.) should also be discarded.
• Freeze suspect foods at zero degrees Fahrenheit for six days.
• Refrigerate all fruit products and store dried fruit products in a glass or plastic container with a tight lid.

DRUGSTORE BEETLE Stegobium paniceum

Size:

1/10 to 1/8 of an inch

Color:

Reddish brown to dark brown

Behavior:

The female drugstore beetle lays up to 75 eggs in her lifetime and may deposit them on more than one food source. Under ideal conditions (85° F and 60-90% relative humidity) the life cycle from egg to adult can take as little as five months. Seven months is more common, however. Varying temperatures and humidity play a significant role in speeding and slowing development of larvae within infested foods. In most cases, the drugstore beetle can complete as many as four generations per year in warm climates or inside warm buildings. The larvae are external feeders and are capable of damaging whole grains or seeds. Adults actively crawl and fly.
The drugstore beetle’s Latin name of paniceum was derived from its habit of feeding on bread. Its common name was given because it can be found infesting drugs and similar products. This beetle, however, will literally feed on any dried, food-based material, especially dried pet foods, cereal products and spices. It has also been observed to damage books by feeding on the bindings. The drugstore beetle can be found worldwide, but is more common in regions with warmer climates or in heated structures in temperate climates.

The control of any stored product pest involves many steps, primary of which is discovery of infested food items or other sources of infestation (e.g., food spillage accumulation). All dried food products need to be inspected for signs of infestation, including cereals, packaged dried foods (e.g., food bars and chocolate) and pet foods. Drugstore beetles have also been found infesting spices, potpourri and decorations made of vegetative materials. Keep in mind that infested items may not always be stored in the kitchen. Spices, potpourri and decorations made of vegetative products may be stored in any room of a house. Infestations have also been traced to caches of nuts and seeds accumulated by squirrels or rodents within attics, walls and chimneys. A pest management professional can be helpful in finding difficult infestation sources. Also consider the following to prevent an infestation:

• Discard infested foods in outdoor trash. Infested decorations (flowers, wreaths, etc.) should also be discarded.
• Freeze suspect foods at zero degrees Fahrenheit for six days. o Clean cabinets and shelves where infested foods are stored by vacuuming and by using soap and water.
• Store all dried food goods, including dried pet foods and birdseed, in a glass or plastic container with a tight lid. If beetles are in that food product then the infestation will be contained and not spread to other foods.
• Consider storing cereals and similar foods in the refrigerator to limit stored product pest problems.
• Consume older food products prior to newer purchases of the same food. Products purchased in larger quantities (e.g., from a wholesale food warehouse) are more likely to become an infestation source if these are stored for long periods of time – especially if they are not stored in containers with tight-fitting lids.

FOREIGN GRAIN BEETLES Ahasverus advena

Size:

1/10 inch

Color:

Reddish Brown

Behavior:

The biology of the foreign grain beetle is not well known. It breeds quickly, completing its cycle from egg to adult in as little as 30 days. It requires moist conditions and develops only when the relative humidity is above 65%. Huge populations are not uncommon under optimum conditions. In such situations, thousands of beetles are forced out of the breeding source in search of fresh media. Many homeowners are introduced to this beetle when purchasing a new home that’s only one or two years old. As a home is being constructed, rain and moisture inevitably fall onto exposed beams prior to the roof and walls being added. If enough moisture has accumulated on the wood, surface fungi may grow on the studs inside the walls. Foreign grain beetles will then enter the walls of homes from the outside and begin feeding and breeding on these surface fungi. After a period of many months to more than one year, the population of these beetles within the walls grows large. Beetles then begin to emerge by the hundreds from under baseboards, from behind electric outlets and from around light fixtures in ceilings. Larvae may also be found on floors near baseboards where adult beetles are found. As strong fliers, the tiny foreign grain beetles spread to all rooms of the house. Initially, only a few beetles may be seen, but when hundreds begin to emerge, homeowners may become annoyed and even panic-stricken and will call a pest management professional for help. Fortunately, the fungi in the walls are not damaging to the wood. It dies after the wood finally dries out, but one to three years may pass before this occurs. The foreign grain beetles also die; however, treatments may be needed in those situations where large numbers are being seen. This same phenomenon may also be encountered in older buildings or other buildings where poor ventilation, water leaks or poor drainage create conditions promoting fungal and mold growth.
A worldwide pest, foreign grain beetles are fungus feeders and are even capable of surviving on pure mold cultures. As a food pest, it is not a great economic concern because it only attacks grain products that are moist, moldy and out-of-condition. Food products attacked include cereal grains, flours, beans, dates, figs, biscuits, yams, tobacco, cocoa, groundnuts, copra and palm kernels.

The control of the foreign grain beetle involves many steps, primary of which is discovery of infested food items or other sources of infestation (e.g., moist areas). This beetle is almost always found to be a pest in newer homes only. When found in older homes, the source is most likely water leaks or other moist conditions that are supporting fungus growth. For example, they may live in a poorly ventilated attic or crawlspace. The beetle infestation will subside once the moist conditions are addressed and dried out. In new homes, however, time will be needed for the moisture to eventually evaporate, sometimes lasting two or more years after construction. In the meantime, homeowners plagued by large numbers of beetles should contact a pest management professional for assistance.

INDIAN MEAL MOTH Plodia interpunctella

Size:

Up to 5/8 inch in length

Color:

The front wing of an Indian meal moth is a reddish copper color on the outer two-thirds.

Behavior:

A female Indian meal moth lays 100-400 eggs on food materials during her life span. The larvae grow to ¾ inch in length and have greenish tinge in appearance. They construct webbing cases or tunnels throughout infested food, usually rendering it unusable. At maturity, the larvae crawl out of infested foods and wander on walls, floors, etc. in search of a site to pupate. The fine silk cocoon, which houses a brownish pupa, is often located in corners, in crevices and behind items against or hanging on walls. If the larvae are unable to find their way out of the food package, they will pupate within that container. The life cycle lasts from 25 to 135 days depending on factors such as temperature and food quality. Adult Indian meal moths tend to avoid light and rest quietly on walls and ceilings. This moth is a weak flier and becomes active after dusk or in low light conditions.
The Indian meal moth is the most common moth of stored dried foods and is the pest moth most often seen in homes. This moth usually enters homes in boxes or bags of infested foods. It appears in all points of the food processing chain from the grain silo to the food plant to the warehouse to the supermarket shelf and ultimately into restaurants, homes and other end-users of food products. This moth infests a wide variety of food items including flour, cereal, nuts, grains, chocolate, birdseed and dried pet foods. It is also present outdoors, occurring naturally and has been known to invade buildings from outside.

The control of any stored product pest involves many steps, primary of which is discovery of infested food items or other sources of infestation (e.g., food spillage accumulation). All dried food products need to be inspected for signs of infestation, including cereals, packaged dried foods (e.g., food bars and chocolate), nuts and pet foods. Indian meal moths have also been found infesting spices, potpourri and decorations made of vegetative materials. Keep in mind that infested items may not always be stored in the kitchen. Spices, potpourri and decorations made of vegetative products may be stored in any room of a house. A common source is bags of birdseed stored in the garage or basement. Infestations have also been traced to caches of nuts and seeds accumulated by squirrels or rodents within attics, walls and chimneys. A pest management professional can be helpful in finding difficult infestation sources. Also consider the following to prevent an infestation:

• Discard infested foods in outdoor trash. Infested decorations (flowers, wreaths, etc.) should also be discarded.
• Freeze suspect foods at zero degrees Fahrenheit for six days. o Clean cabinets and shelves where infested foods are stored by vacuuming and by using soap and water.
• Store all dried food goods, including dried pet foods and birdseed, in a glass or plastic container with a tight lid. If beetles are in that food product then the infestation will be contained and not spread to other foods.
• Consider storing cereals and similar foods in the refrigerator to limit stored product pest problems.
• Consume older food products prior to newer purchases of the same food. Products purchased in larger quantities (e.g., from a wholesale food warehouse) are more likely to become an infestation source if these are stored for long periods of time – especially if they are not stored in containers with tight-fitting lids.

LARDER BEETLE Dermestes lardarius

Size:

1/4 to 1/2 inch

Color:

Dark brown to black with pale, yellow six-spotted band across front half of wing covers. The underside and legs are covered with fine yellow hairs.

Behavior:

The genus name “Dermestes” comes from Greek and means “to devour a skin.” Adult larder beetles are often found outside overwintering in crevices of bark. In late spring or early summer, they may enter structures seeking a food source on which to deposit eggs. The eggs are generally laid directly on the food source although they may be deposited into nearby crevices. Egg laying lasts 2-3 months through the summer and a single female deposits as many as 200 to 800 eggs. The eggs hatch within 12 days and the larvae feed continuously on their food source, preferring those with some fat or oil content. They will, however, feed on dead cluster flies and other insects inside attics or walls. They may also be found in the dead insect accumulations in the bottom of insect light traps. Although larder beetle larvae are active and fairly agile, they become immobile if disturbed and “play possum” until the danger has passed. The larvae have strong mandibles and have been observed to bore into both hard and soft woods and even lead. Larvae molt up to six times before pupating. The mature larvae wander from the food source and may bore into anything in the immediate vicinity to find a site to pupate. The entire life cycle may be completed within 40 to 50 days under suitable conditions.
Larder beetles are common pests of many industrial, commercial sites where animal protein is processed or stored. They may be found in homes feeding on dead insects or a rodent or bird carcass inside walls, attics, crawlspaces and basements. Foods attacked include ham, bacon, meats, cheese, stored tobacco, dried fish and dried pet food as wells as hides, skin, bones and dead insects. These beetles may be used by museums to clean flesh and hides off animal skeletons.

The control of any stored product pest involves many steps, primary of which is discovery of infested food items or other sources of infestation (e.g., food spillage accumulation). The larder beetle will be associated with a moist protein source or accumulations of dead insects. A pest management professional can be helpful in finding difficult infestation sources. Once discovered, the source will need to be removed or a residual treatment applied into the void to kill the beetles and larvae feeding on the source.

MEDITERRANEAN FLOUR MOTH Anagasta kuehniella

Size:

Up to 5/8 inch in length; wingspan less than 1 inch.

Color:

The front wings are a pale gray with transverse black wavy bars.

Behavior:

The female deposits her eggs in any suitable food material and usually fastens them to the food particles. The young larva spins silken tubes constantly and spends its time in these tubes feeding. The silk causes balls of form, which can clog machinery in flour mills, necessitating downtime to clean the machines. The larvae may pupate in a cocoon within the flour or on the surface of the flour. They may also pupate in some crack or crevice either within or without a cocoon, often migrating from the food source in search of a pupation site. These larvae are therefore commonly seen significant distances from the breeding source. The life cycle from egg to adult can be completed in four to six weeks in heated buildings and six or more generations per year can occur. The adult moths are active fliers and fly in a very rapid zigzag fashion.
This moth is a significant pest of flour and is a serious pest of mills and warehouses. It also infests nuts, chocolate, seeds, beans, biscuits, dried fruits and stored foods of many kinds. They have even been found feeding in brood combs of honeybee nests. Mediterranean flour moths are not uncommon in supermarkets, drug stores and convenience stores where it can be found infesting chocolate, birdseed and pet foods. It may also be found in restaurants, homes and other end-users of food products.

The control of any stored product pest involves many steps, primary of which is discovery of infested food items or other sources of infestation (e.g., food spillage accumulation). All dried food products need to be inspected for signs of infestation, including cereals, packaged dried foods (e.g., food bars and chocolate), nuts and pet foods. Keep in mind that infested items may not always be stored in the kitchen. Items containing or made of vegetative products may be stored in any room of a house. A common source may be bags of bird seed or pet foods stored in the garage or basement. A pest management professional can be helpful in finding difficult infestation sources. Also consider the following to prevent an infestation:

• Discard infested foods in outdoor trash. Infested decorations (flowers, wreaths, etc.) should also be discarded.
• Freeze suspect foods at zero degrees Fahrenheit for six days.
• Clean cabinets and shelves where infested foods are stored by vacuuming and by using soap and water.
• Inspect the home to find and remove as many cocoons as possible that may be located in corners, behind pictures, etc.
• Store all dried food goods, including dried pet foods and birdseed, in a glass or plastic container with a tight lid. If beetles are in that food product then the infestation will be contained and not spread to other foods.
• Consider storing cereals and similar foods in the refrigerator to limit stored product pest problems.
• Consume older food products prior to newer purchases of the same food. Products purchased in larger quantities (e.g., from a wholesale food warehouse) are more likely to become an infestation source if these are stored for long periods of time – especially if they are not stored in containers with tight-fitting lids.

RED OR CONFUSED FLOUR BEETLE Tribolium castaneum & confusum

Size:

1/8 of an inch

Color:

Reddish brown

Behavior:

The red and confused flour beetles are nearly identical in biology and habits except that the red flour beetle flies and the confused flour beetle does not. The threat of the red flour beetle invading from an outside food source, such as grain spillage, must therefore be considered. Red and confused flour beetles are capable of breeding year-round in heated buildings. The red flour beetle is found more often in southern, warmer states and the confused flour beetle is seen in northern areas. Either species, however, could be encountered anywhere. These flour beetles are also known as “bran bugs,” being very significant pests of flour and flour by-products. Female beetles deposit eggs in twos or threes within the food material until eventually 300 to 400 eggs are laid. The larvae hatch from these eggs in about nine days and go through from 5 to 18 molts. The life cycle from egg to adult may take 7 weeks to 3 months depending on temperature and humidity conditions as well as quality of the food source. The adult beetles may live up to three years or longer.
Flour beetles are scavengers in that they cannot attack whole grains and must rely on other insects such as rice weevils or lesser grain borers to damage the kernels first. These beetles are most common in processed grain products and their flattened bodies permit them to work their way into almost any package. Flour and other processed food products heavily infested by these beetles often develop a grayish tint. This graying also promotes the growth of mold, which further contaminates the food product. Additionally, secretions from the beetles may add a disagreeable odor to the food product.

The control of any stored product pest involves many steps, primary of which is discovery of infested food items or other sources of infestation (e.g., food spillage accumulation). All dried food products need to be inspected for signs of infestation, including cereals, packaged dried foods (e.g., food bars and chocolate)and pet foods. Keep in mind that infested items may not always be stored in the kitchen. Products made of or containing vegetative materials may be stored in any room of a house. Infestations have also been traced to old rodent baits placed in attics, wall voids and similar out of the way locations. A pest management professional can be helpful in finding difficult infestation sources. Consider the following to prevent an infestation:

• Discard infested foods in outdoor trash. Infested decorations (flowers, wreaths, etc.) should also be discarded.
• Freeze suspect foods at zero degrees Fahrenheit for six days. o Clean cabinets and shelves where infested foods are stored by vacuuming and by using soap and water.
• Store all dried food goods, including dried pet foods and birdseed, in a glass or plastic container with a tight lid. If beetles are in that food product then the infestation will be contained and not spread to other foods.
• Consider storing cereals and similar foods in the refrigerator to limit stored product pest problems.
• Consume older food products prior to newer purchases of the same food. Products purchased in larger quantities (e.g., from a wholesale food warehouse) are more likely to become an infestation source if these are stored for long periods of time – especially if they are not stored in containers with tight-fitting lids.

RICE & GRANARY WEEVILS Sitophilus oryzae, Sitophilus granarius

Size:

1/8 inch in length

Color:

The rice weevil is dark brown and usually has four light-colored patches on its wing covers. The granary weevil is uniformly dark brown in color.

Behavior:

Both the rice and the granary weevil are internal feeders and the larva develops inside whole grain kernels. The female weevil bores a small hole into a grain kernel and deposits a single egg into the hole. She seals this hole with a gelatinous material and then repeats the process on kernel after kernel until she deposits 300-400 eggs. As a general rule, however, about 50% of the eggs do not hatch. The “C” shaped, creamy white, legless larva emerges from the egg and completes its life feeding within the kernel. The kernel will eventually be hollowed out and the larva pupates within. After pupation, the adult beetle remains inside the kernel for a while before chewing its way out. The open, round exit holes are sign of a weevil infestation. Weevil exit holes differ from the exit holes created by the grain moth because they are open. The moth leaves a little, hinged “lid” over the hole. Within infested grain, the size of the weevils seen can vary greatly. A weevil’s size is dependant on the size of the grain kernel in which the larva developed. Rice weevils are prolific breeders and can build up huge populations in stored grain to the point where the grain has little value as a food product. Infestations located in storage bins, silos and grain elevators have been found to a depth of about 5 feet. The grain deeper than that is usually too warm to support the weevils’ survival. When disturbed, both types of weevil “play dead” by drawing their legs close to the body. They then lie still for several minutes before resuming movement. The granary weevil does not fly while the rice weevil is an active flier. It often flies to grain storage bins and buildings from nearby fields and from one end of a warehouse to the other.

Both rice and granary weevils mainly attack whole grains, such as wheat, corn, barley and rice. These weevils may also be found infesting in such foods as macaroni and spaghetti when they get old. Rice weevils also feed on beans, nuts and cereals and have been observed sucking the juice from apples and pears. In homes, infestations are generally found in bird seed, nuts, decorative Indian corn and, in rare instances, in old pasta stored in cupboards. The adults feed on the same foods as the larvae but are not as restricted in their diets because the larvae need to develop inside whole grains. The rice and granary weevils are the most economically significant pests of stored whole grains in the world. The granary weevil is more common in northern states while the rice weevil is more prevalent in the southern states. Both beetles, however, may be found throughout the world. In southern states, adult rice weevils will overwinter in the fields.

The control of any stored product pest involves many steps, primary of which is discovery of infested food items or other sources of infestation (e.g., food spillage accumulation). All products containing or made of whole grains need to be inspected. Decorative items, such as Indian corn and shadow boxes containing seeds also need to be checked. Rice and granary weevils have also been found infesting old pasta products and bird seed. On rare occasions, infestations have also been traced to caches of nuts and seeds accumulated by squirrels or rodents within attics, walls and chimneys. A pest management professional can be helpful in finding difficult infestation sources. Consider the following to prevent an infestation:

• Discard infested foods in outdoor trash. Infested decorations (flowers, wreaths, etc.) should also be discarded.
• Freeze suspect foods at zero degrees Fahrenheit for six days.
• Clean cabinets and shelves where infested foods are stored by vacuuming and by using soap and water.
• Store all dried food goods, including dried pet foods and birdseed, in a glass or plastic container with a tight lid. If beetles are in that food product then the infestation will be contained and not spread to other foods.
• Consider storing cereals and similar foods in the refrigerator to limit stored product pest problems.
• Consume older food products prior to newer purchases of the same food. Products purchased in larger quantities (e.g., from a wholesale food warehouse) are more likely to become an infestation source if these are stored for long periods of time – especially if they are not stored in containers with tight-fitting lids.

SAWTOOTHED & MERCHANT GRAIN BEETLES

Oryzaephilus surinamensis oryzaephilus mercator

Size:

1/10 inch

Color:

Brown to dark brown

Behavior:

One female merchant or sawtoothed grain beetle may produce up to 285 eggs deposited singly or in small batches within the food. Larvae are active crawlers and move about through the food as they feed. They are scavengers and not capable of feeding on whole grains unless other insects have first attacked the kernels. After molting 2 to 4 times, the larva pupates and the adults emerge in about 7 days. The entire life cycle from egg to adult takes 27 to 50+ days, depending on the food quality and temperature. The female beetle lives from 6 to 10 months and several generations per year may occur. Large populations of these beetles can develop in short periods, forcing adults to leave infested foods seeking new food sources. They have been known to invade every package or food stored near an infested food product. Infestations, therefore, are often widespread throughout a room or area. The merchant grain beetle can fly, but the sawtoothed grain beetle cannot.
These grain beetles are two of the more commonly encountered insects in processed grain, oats, pet foods and seeds. Merchant grain beetles are found more often in foods that are high in oils and fats, such as peanuts or birdseed. Other foods attacked include rice, cereals, dried fruits, breakfast foods, grain meals, sugar, chocolate, drugs, pastas and tobacco. Its varied food preferences make it one of the most commonly encountered stored product beetles in retail food stores, warehouses and homes. In unheated grain facilities in northern states, breeding ceases at the onset of cold weather.

The control of any stored product pest involves many steps, primary of which is discovery of infested food items or other sources of infestation (e.g., food spillage accumulation). All dried food products need to be inspected for signs of infestation, including cereals, packaged dried foods (e.g., food bars and chocolate) and pet foods. Keep in mind that infested items may not always be stored in the kitchen. A common source is bags of birdseed stored in the garage or basement. Infestations have also been traced to caches of nuts and seeds accumulated by squirrels or rodents and old rodenticide baits within attics, walls and chimneys. A pest management professional can be helpful in finding difficult infestation sources. Also consider the following to prevent an infestation:

• Discard infested foods in outdoor trash. Infested decorations (flowers, wreaths, etc.) should also be discarded.
• Freeze suspect foods at zero degrees Fahrenheit for six days.
• Clean cabinets and shelves where infested foods are stored by vacuuming and by using soap and water.
• Store all dried food goods, including dried pet foods and birdseed, in a glass or plastic container with a tight lid. If beetles are in that food product then the infestation will be contained and not spread to other foods.
• Consider storing cereals and similar foods in the refrigerator to limit stored product pest problems.
• Consume older food products prior to newer purchases of the same food. Products purchased in larger quantities (e.g., from a wholesale food warehouse) are more likely to become an infestation source if these are stored for long periods of time – especially if they are not stored in containers with tight-fitting lids.

WAREHOUSE & CABINET BEETLES Trogoderma spp.

Size:

1/8 to 1/4 inch

Color:

Adults are dark brown and oval in shape with varying patterns of tan and yellow markings on wing covers. Larvae are tan and have a long body covered with stout hairs.

Behavior:

Several members of the genus Trogoderma in the Dermestidae beetle family are important pests of stored food products as well as of fabrics and hides. Both the adults and larvae of Trogoderma are often difficult to distinguish from one another and generally require an entomologist strongly familiar with the taxonomy of these beetles. The species involved in this group include the Khapra beetle, T. granarium, the warehouse beetles, T. variabile and T. ornatum and the larger cabinet beetle, T. inclusum and the cabinet beetle, T. glabrum. Other species may also be encountered. In most cases, pest management professionals refer to these beetles simply as Trogoderma beetles or use the term “warehouse” or “cabinet” beetles. Warehouse and cabinet beetles are a nuisance to insect collectors around the world because they infest boxes of stored, dried insects and reduce them to collections of dust and insect parts. Therefore, any accumulation of dead insects in walls, windowsills, light fixtures or an insect light trap can serve as a source for infestations of Trogoderma beetles. Trododerma beetles are also considered a potential health hazard in food products. The hairs on the larvae are equipped with barbs or are sharply pointed. Hairs shed by this beetle can be irritating to the mouth, esophagus and digestive tract of many people who ingest the hairs left on their food. The life history of Trogoderma beetles vary among the species. For example, the warehouse beetle female, T. vaiable, deposits up to 90 or more eggs within the infested food source. The larvae are very active and crawl throughout infested product and also move into adjacent areas to infest other food sources. In warm conditions, the entire life cycle can be completed in as little as 45 days. Conversely, the life cycle of T. ornatum, a species very common in homes, takes about six months from egg to adult under optimum conditions. Adult females of the larger cabinet beetle, T. inclusum, deposit up to 45 eggs within the food source and these hatch in 8 to 12 days. The entire life cycle of this species is completed in about six months.
The warehouse beetle, T. variable, derives its name from the fact that it is the most common species found in warehouses. It has the widest food preferences of any of these beetles, feeding on a wide variety of foods including cereals, candy, cocoa, cookies, corn, corn meal, fish meal, pet foods, flour, nuts, dried peas and beans, potato chips, pastas, spices, dead animals and dead insects. The warehouse beetle occurs across the United States and is a common pest in seaports around the world. A closely related species, T. ornatum, is primarily a pest in museums, especially to insect collections. It is more common in northern states, where it occurs outdoors in the cracks of hollow trees and in bird nests. This beetle may be the most common species found in homes and is common in attics. It will feed on the carcasses of dead rodents, dead insects and rodent baits in attics, basements and crawlspaces. This beetle also attacks wool, feathers, furs, skins, bee glue, cocoons, grain, nuts, wheat, corn, malt, cayenne pepper, old flower bulbs, pumpkin seeds, castor beans and tobacco. One report describes T. ornatum larvae feeding on dead termites in drywood termite galleries. Another cosmopolitan species is the larger cabinet beetle, T. inclusum, which is a pest of seed collections. It also can be found in stored wheat, rice and corn as well as woolen clothing, dried insects, dried casein and corn meal. Because many Trogoderma beetles occur naturally outdoors and are able to fly, total elimination of these beetles in a home or commercial building may not be possible in many areas.

The control of Trogoderma beetles involves many steps, primary of which is discovery of infested food items or other sources of infestation (e.g., dead insects, animal carcasses, items made of wool). Because these beetles can survive on such a wide variety of items, elimination of infestations is very difficult, if not impossible in many situations. All dried food products need to be inspected for signs of infestation, including cereals, packaged dried foods (e.g., food bars and chocolate)and pet foods. Window sills, light fixtures and the attic need to be checked for accumulations of insects. Also in attics, the presence of old rodent bait, dried animal carcasses (usually mice), bird nests and items made of wool, horsehair or other natural fibers needs to be noted. The basement, garage and crawlspace, if present, will require a similar inspection. Homeowners should remember if the home has ever experienced an infestation of lady beetles or cluster flies as large numbers of these insects can often die in larger numbers inside walls and attics. Also, it is important to note where yellow jackets may have nested within a wall. Infestations may also be associated with caches of nuts and seeds accumulated by squirrels or rodents within attics, walls and chimneys. A pest management professional can be helpful in finding difficult infestation sources. Consider the following to prevent an infestation:

• Discard infested foods in outdoor trash. Infested decorations (flowers, wreaths, etc.) should also be discarded.
• Discard bird nests, animal carcasses, dead insect accumulations and old rodent bait. o Freeze suspect foods at zero degrees Fahrenheit for six days.
• Clean cabinets and shelves where infested foods are stored by vacuuming and by using soap and water.
• Store all dried food goods, including dried pet foods and birdseed, in a glass or plastic container with a tight lid. If beetles are in that food product then the infestation will be contained and not spread to other foods.
• Consider storing cereals and similar foods in the refrigerator to limit stored product pest problems.
• Consume older food products prior to newer purchases of the same food. Products purchased in larger quantities (e.g., from a wholesale food warehouse) are more likely to become an infestation source if these are stored for long periods of time – especially if they are not stored in containers with tight-fitting lids.

CARPET BEETLE Anthrenus spp.

Size:

Tiny, round beetles with larvae that grow up to 1/4-inch in length; the adults grow to 1/16-inch.

Color:

While generally tan in color, they are covered by tiny black, brown, and white scales, and have numerous tufts of stiff hairs on the body.

Behavior:

Fabric pests such as carpet beetles, although not particularly dangerous, can sometimes cause irreparable damage to personal belongings. These beetles are able to digest animal hairs and, therefore, feed on almost any item made of natural fibers, particularly wool and cashmere.

WEBBING CLOTHES MOTH Tineola bisselliella

Size:

About 3/8-inch long

Color:

Cream, with a tuft of red hair on the top of the head. The larvae are white.

Behavior:

Fabric pests such as clothes moths, although not particularly dangerous, can sometimes cause irreparable damage to personal belongings. These moths are able to digest animal hairs and, therefore, feed on almost any item made of natural fibers, particularly wool and cashmere.