Stored Product Pests

An integrated pest management program is necessary to protect our food commodity from unwanted pests. In 1990, postharvest losses in the United States were estimated to be around $500 million per year. It is critical to know what species of pest you are dealing with in order to implement a successful program.

Below are some stored product pests FSS deals with on a daily basis. With our team of board certified entomologists, we are able to identify unknown species of insects and help you eradicate current and prevent future insect infestations. If you have a question or need help on pest identification, contact us at info@fumigationzone.com or 1-800- 992-1991.

Stored Product Insects

Beetles (Coleoptera)

Moths (Lepidoptera)

Psocids (Psocoptera)

Silverfish (Thysanura)

Stored Product Vertebrates

Birds (Aves)

Rodents (Rodentia)

Angoumois Grain Moth (Sitotroga Cerealella)

  • Angoumois Grain Moth
    • Description
    • Adults are pale grayish brown with a wingspan of about 12mm to 14mm
    • Life History
    • Females lay 40-300 eggs for about 1 month
    • Larvae burrow into grain to feed, and emerge as an adult
    • Damage
    • Feed on barley, corn, rice, sorghum, and wheat
    • Larvae chew holes and burrow into food commodity
    • Adults fly, which allows easy dispersal for infestations in different areas
    • Infestation can lead to heating and increased moisture levels in grain

Cadelle (Tenebroides Mauritanicus)

  • Cadelle
    • Description
    • One of the largest major stored product insects; adults are 6-19mm and larvae can get up to 19mm
    • Adults are shiny black/brown
    • Adults are able to fly
    • Life History
    • Females lay 425-3500 eggs over a 6-12 month lifespan
    • Prey on other stored product insects
    • Damage
    • Feed on grains, nuts, dried fruit, and spices
    • Adults and larvae feed on the germ of a grain kernel
    • Larvae can burrow into wooden structures or plastered walls
    • Adults and larvae can also chew holes in flour sacks and food cartons

Cigarette Beetle (Lasioderma Serricorne)

  • Cigarette Beetle
    • Description
    • Adults are an oval reddish/brown, about 2.5 to 3.5mm in length
    • Adults areable to fly well
    • Larvae are white with numerous long hairs
    • Life History
    • Females lay 30-42 eggs over a 1-month lifespan
    • Infestation can establish at temperatures as low as 63°F, but development is prolonged
    • Optimum development takes place around 90°F at a relative humidity of 70%
    • Damage
    • Feed on spices, seeds, flour, leather, animal feed, grain, rice, drugs, driedmeat, and a variety of other dried products
    • Larvae chew holes and burrow into food commodity
    • Larvae shed cocoons that contaminate food which can cause allergic reactions

Confused Flour Beetle (Tribolium confusum)

  • Confused Flour Beetle
    • Description
    • Adults are reddish brown, about 4mm in length
    • Similar to the red flour beetle, but do not have distinctive 3 knobs on antenna
    • Adults are unable to fly
    • Life History
    • Females lay around 200-500 eggs over a 6-12 month lifespan
    • Infestation can establish at temperatures as low as 63°F, but development is prolonged
    • Optimum development takes place around 90°F at a relative humidity of 70%
    • Have one of the highest population growth rates for stored product insects
    • Damage
    • Feed on grain, flour, animal feed, cereal products, beans, and spices
    • Can release a pungent odor in infested commodity
    • Infestation can lead to heating and increased moisture levels in grain

Drugstore Beetle (Stegobium Paniceum)

  • Drugstore Beetle
    • Description
    • Adults are a dark reddish brown, about 2.5 to 3mm in length
    • Adults have distinct 3 segmented club antennae
    • Adults are able to fly well
    • Larvae are white with numerous long hairs
    • Life History
    • Females lay around 75 eggs over a 1-4 month lifespan
    • Infestation can establish at temperatures as low as 59°F, but development is prolonged
    • Optimum development takes place around 81°F at a relative humidity of 70%
    • Damage
    • Feed on spices, seeds, flour, leather, animal feed, grain, and cereal
    • Adults and larvae chew holes and burrow into food commodity
    • Larvae shed cocoons that contaminate food which may cause allergic reactions

Flat Grain Beetle (Cryptolestes Pusillus)

  • Flat Grain Beetle
    • Description
    • Adults are reddish brown and flattened, small, and about 1.5 to 2mm in length
    • Similar in appearance to rusty grain beetle
    • Adults are able to fly
    • Life History
    • Females lay around 20-335 eggs over a 2-20 month lifespan
    • Eggs are laid in crevices and in food commodity
    • Damage
    • Feed on grain, wheat, beans, oats, cereal products, rice, and sorghum
    • Damage usually occurs to grain stored under high moisture conditions
    • Both adults and larvae feed on germ and endosperm of kernels
    • May spread fungal spores through grain commodity
    • Infestation can lead to heating and increased moisture levels in grain

Granary Weevil (Sitophius Granarius)

  • Granary Weevil
    • Description
    • Adults have a prolonged head or snout
    • Adults are a uniform dark reddish brown, about 5mm in length
    • Adults are unable to fly
    • Life History
    • Females lay 200 eggs over a 7-8 month lifespan
    • Females individually lay eggs within grain kernels
    • Infestation can establish at temperatures as low as 60°F, but development is prolonged
    • Optimum development takes place between 78°F to 86°F at a relative humidity of 70%
    • Damage
    • Feeds on barley, corn, sorghum, rice, rye, and wheat
    • Grains with round holes are a sign of infestation by emerging adults
    • Can almost complete total destruction of products at high densities
    • Infestation can lead to heating and increased moisture levels in grain

House Mouse (Mus Musculus)

  • House Mouse
    • Description
    • Small rodent, about 5-7 inches in length
    • Light gray to light brown with a lighter belly
    • Life History
    • Females can produce 3-14 (6-8 on average) pups every 20 days, with 5-10 litters per year
    • Life expectancy is about 2-3 years
    • Short maturation time and high reproduction rate enable rapid infestation
    • Damage
    • Feed mainly on grains, meat products, insects, and cereal
    • Not typically an indoor pest and is native to North America
    • Can transmit diseases, contaminate food, and damage food packaging

Indian Meal Moth (Plodia Interpunctella)

  • Indian Meal Moth
  • Indian Meal Moth Larvae
    • Description
    • Adults are bi-colored with a cream/yellow at the base and a red/dark gray on the outer portion of the wings
    • About 12-14mm wingspan length and 6-7mm body length
    • Life History
    • Females lay 200-400 eggs for about a 7-10 day lifespan
    • Infestation can establish at temperatures as low as 64°F, but development is prolonged
    • Optimum development takes place around 86°F at a relative humidity of 70%
    • Damage
    • Feed on cereal, corn, rice, sorghum, spices, nuts, dried commodities and wheat
    • Larvae eat broken kernels of grain and grain dust
    • Larvae leave silky webbing that can contaminate commodity and clog machinery
    • Webbing can result in condensation that causes increased humidity and micro-habitats for toxic molds
    • Adults fly which allow easy dispersal for infestations in other areas
    • Infestation can lead to heating and increased moisture levels in grain

Lesser Grain Borer (Rhyzopertha Dominica)

  • Lesser Grain Borer
    • Description
    • Adults are a dark reddish brown, about 3mm in length
    • Adults have distinct 3-segmented club antennae
    • Adults are able to fly.
    • Life History
    • Females lay 200-500 eggs over a 4-8 month lifespan
    • Females lay eggs within grain kernels
    • Infestation can establish at temperatures as low as 64°F, but development is prolonged
    • Optimum development takes place around 93°F at a relative humidity of 70%
    • Damage
    • Feeds on nearly all grains especially barley, corn, sorghum, rice, and wheat
    • Grains with round and irregular holes are a sign of infestation by burrowing adults and larvae
    • Can almost complete total destruction of product at high densities
    • Infestation can lead to heating and increased moisture levels in grain

Indian Meal Moth (Plodia Interpunctella)

  • Mediterranean Flour Moth
  • Mediterranean Flour Moth Larvae
    • Description
    • Adults are uniformly gray with brown and white markings
    • Relatively large, 20-25mm wingspan and 9-12mm in body length
    • Life History
    • Females lay 100-675 eggs for a 10-14 day lifespan
    • Infestation can establish at temperatures as low as 46°F, but development is prolonged
    • Optimum development takes place around 77°F at a relative humidity of 70%
    • Damage
    • Feed on wheat, flour, and cereal products
    • Larvae eat whole grains, prefering the bran and germ
    • Larvae leave silky webbing that can contaminate commodity and clog machinery
    • Webbing can result in condensation that causes increased humidity and micro-habitats for toxic molds
    • Adults fly which allow easy dispersal for infestations in other areas
    • Infestation can lead to heating and increased moisture levels in grain

Merchant Grain Beetle (Oryzaephilus Mercator)

  • Merchant Grain Beetle
    • Description
    • Adults are slender brown with serrated sides on the body, about 3mm in length
    • Similar to saw-toothed grain beetle, but have a wider width of the temple
    • Adults are able to fly
    • Life History
    • Females lay around 45-285 eggs over a 6-36 month lifespan
    • Infestation can establish at temperatures as low as 64°F, but development is prolonged
    • Less cold tolerant than the saw-toothed grain beetle
    • Optimum development takes place around 90°F at a relative humidity of 70%
    • Damage
    • Feed on oats, bran, seeds, wheat, barley, and animal feed
    • Adults feed on grain dust and broken kernels
    • Larvae feed on both drain dust and germ
    • Infestation can lead to heating and increased moistture levels in grain

Norway Rat (Rattus Norvegicus)

  • Norway Rat
    • Description
    • Large rodent, about 8-10 inches in body length and 7-10 inches in tail length
    • Brown or dark grey, with a lighter belly
    • Life History
    • Females can produce 8-12 young, with 5-8 litters per year
    • Life expectancy is about 2-3 years
    • Short maturation time and high reproduction rate enable rapid infestation
    • Damage
    • Feed mainly on grains, meat products, insects, and cereal
    • Can transmit diseases, contaminate food, and damage food packaging

Psocids (Order: Psocoptera)

  • Psocid
    • Description
    • Very small, about 2mm or less in length
    • Soft bodied and often translucent
    • Life History
    • Females lay about 60 eggs for about a 1-3 month lifespan
    • Require warm, moist, high humid environments
    • Infestation can establish at temperatures as low as 64°F, but development is prolonged
    • Optimum development takes place around 82°F at high humidity
    • Damage
    • Feed on animal and plant products, fungi, stored grain, packaged food, glues, paper products, and fabrics
    • Feed on damaged and broken kernels in moist areas
    • May cause inhalation allergic reactions and respiratory issues

Red Flour Beetle (Tribolium Castaneum)

  • Red Flour Beetle
    • Description
    • Adults are reddish brown, about 4mm in length
    • Similar in appearance to the confused flour beetle
    • Red flour beetles have 3 knobs on end of antenna
    • Adults are able to fly
    • Life History
    • Females lay around 200-450 eggs over a 6-18 month lifespan
    • Infestation can establish at temperatures as low as 68°F, but development is prolonged
    • Optimum development takes place around 97°F at a relative humidity of 70%
    • Have one of the highest population growth rates for stored product insects
    • Damage
    • Feed on grain, flour, animal feed, cereal products, beans, and spices
    • Can release a pungent odor in infested commodity
    • Infestation can lead to heating and increased moisture levels in grain

Rice Weevil (Sitophilus Oryzae)

  • Rice Weevil
    • Description
    • Adults have prolonged head or snout
    • Adults are dark brown with 4 distinct lighter yellowish spots, about 2.5 to 4mm in length
    • Adults are able to fly
    • Life History
    • Females lay 300-575 eggs over a 5-8 month lifespan
    • Females individually lay eggs within grain kernels
    • Infestation can establish at temperatures as low as 59°F, but development is prolonged
    • Optimum development takes place around 84°F at a relative humidity of 70%
    • Damage
    • Feed on barley, corn, sorghum, rice, rye, and wheat
    • Grains with round holes are a sign of infestation by emerging adults
    • Can almost complete total destruction of product at high densities
    • Infestation can lead to heating and increased moisture levels in grain

Drugstore Beetle (Stegobium Paniceum)

  • Rusty Grain Beetle
    • Description
    • Adults are reddish brown and flattened, small, and about 1.5 to 2mm in length
    • Similar in appearance to the flat grain beetle
    • Adults are able to fly
    • Life History
    • Females lay around 200-500 eggs over a 6-9 month lifespan
    • Eggs are laid in crevices and in food commodity
    • Damage
    • Feed on grain, wheat, beans, oats, cereal products, rice, and sorghum
    • Damage usually occurs to grain stored under high moisture conditions
    • Both adults and larvae feed on germ and endosperm of kernel
    • May spread fungal spores through grain commodity
    • Infestation can lead to heating and increased moisture levels in grain

Sawtoothed Grain Beetle (Oryzaephilus Surinamensis)

  • Sawtoothed Grain Beetle
    • Description
    • Adults are a slender brown with serrated sides on the body, about 3mm in length
    • Similar to merchant grain beetle, but have a  narrower width of the temple
    • Adults are unable to fly
    • Life History
    • Females lay around 45-285 eggs over a 6-36 month lifespan
    • Infestation can establish at temperatures as low as 63°F, but development is prolonged
    • More cold tolerant than the merchant grain beetle
    • Optimum development takes place around 90°F at a relative humidity of 70%
    • Damage
    • Feed on oats, bran, seeds, wheat, barley, and animal feed
    • Adults feed on grain dust and broken kernels
    • Larvae feed on both grain dust and germ
    • Infestation can lead to heating and increased moisture levels in grain

Sliverfish (Order: Thysanura)

  • Silverfish
    • Description
    • Range from 3-30mm in length (depends on life stage)
    • Brownish/cream in color, 2 long antennae with 3 tails
    • Life History
    • Females lay about 200 eggs for about 2-3 year lifespan
    • Require moist, humid environments
    • Damage
    • Feed on flour, pet food, books, starchy substances, and vegetables
    • Generalist feeders that cause irregular shaped holes in paper and fabrics

Warehouse Beetle (Trogoderma Variabile)

  • Warehouse Beetle
  • Warehouse Beetle Larvae
    • Description
    • Adults are dark brown with 3 lighter brown or reddish bands, about 2-4.5mm in length
    • Larvae are white with tufts of dense hairs
    • Adults are able to fly
    • Life History
    • Females lay around 100 eggs over a 1-2 month lifespan
    • Infestation can establish at temperatures as low as 64°F, but development is prolonged
    • Optimum development takes place around 90°F at a relative humidity of 70%
    • Damage
    • Feed on seeds, beans, nuts, animal feed, barley, and wheat
    • Larvae chew holes and burrow into food commodity
    • Larvae can damage all parts of seed except the shell
    • Larvae shed cocoons that contaminate food which can cause allergic reactions

Yellow Mealworm (Tenebrio Molitor)

  • Yellow Mealworm
  • Yellow Mealworm Larvae
    • Description
    • Shiny dark brown/black, large, and about 12-18mm in length
    • Larvae are very large, reaching 30mm in length
    • Larvae are initially white, but turn a yellowish color as they mature
    • Life History
    • Females can produce 275 to 460 eggs over a 2-3 month lifespan
    • Larvae are resistant to dry and cold conditions and are able to survive up to 3 weeks at 5°F
    • Optimum development takes place around 77°F at a relative humidity of 70%
    • Damage
    • Feed on flour, meal, bran, grain, cereals, bread, crackers, mill sweepings, meat products, and dead insects
    • Often found in dark and damp areas, feeding on decaying and moist grain

European Starling (Sturnus Vulgaris)

  • European Starling
    • Description
    • Iridescent blue to black, summer plumage is flecked with gold
    • Large and distinctively yellow or olive colored bill
    • Life History
    • Females can produce around 6 eggs, with about 2 broods per year
    • Roost in very large flocks
    • Life expectancy is about 15-20 years
    • Damage
    • Feed mainly on grains, seeds, insects, and garbage
    • Can transmit diseases and contaminate food with droppings

House Sparrow (Passer Domesticus)

  • House Sparrow
    • Description
    • Adult males have prominet black throat, white cheeks, dark grey crown, and chestnut colored back.
    • Adult females and immatures are dull gray on top and light gray on bottom
    • Life History
    • Females can produce 4-8 eggs, with 2-5 broods per year
    • Life expectancy is about 16 years
    • Damage
    • Feed mainly on grains, insects, fruits, and buds of trees and bushes
    • Can transmit diseases and contaminate food with droppings

Pigeon (Columba Livia)

  • Pigeon
    • Description
    • Dark bluish-gray head, neck, and chest
    • Neck and wink feathers are a glossy yellowish, greenish, and reddish-purple iridescence
    • Life History
    • Females can produce 1 to 2 eggs per clutch, with about 2 broods per year
    • Normally congregate in flocks of seeral hundred birds
    • Adapted very well to man-made environments
    • Life expectancy is about 3-5 years in the wild and 15 years in captivity
    • Damage
    • Feed mainly on grains, seeds, insects, and garbage
    • Can transmit diseases and contaminate food with droppings

Deer Mouse (Peromyscus Maniculatus)

  • Deer Mouse
    • Description
    • Commonly called a field mouse
    • Bicolored body and tail, with a white belly and brownish back
    • Small, abouot 3-4 inches in body length
    • Life History
    • Females can produce 3-5 young, with about 3-4 litters per year
    • Life expectancy is about 4 years
    • Damage
    • Feed mainly on grains, seeds, and insects
    • Not typically an indoor pest and is native to North America
    • Can transmit diseases and contaminate food with droppings