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Rice Weevils

Adult rice weevils are reddish-brown in color with four faint red or yellow spots on their wing covers.  Rice weevil adults are strong fliers, which may result in the spread of infestation from one area within the home to another.  They are a snout weevils that are approximately 1/8 of an inch in length.  Therefore, the head is elongated, tapering into a long slender snout.  Adult female rice weevils lay roughly 300 to 400 eggs within her lifetime by boring a small hole into a kernel in order to deposit the egg.  The hole is then sealed with a gelatinous fluid that the female produces.  Larvae hatch within a few days and begin feeding inside the grain kernel.  Molting will occur four times within a 32 day period.  Larvae are legless white grubs with dark head capsules.  Their upper body is rounded with the underside being flat.  At the end of the 32 days, the larvae pupate in order to finish development and become an adult rice weevil.  The life cycle takes just over a month and adults live approximately three to six months.

Rice weevils are found in homes and stored grain products worldwide.  They infest only whole grains and while larvae feed strictly on grains, adults have been observed feeding on a variety of items including beans, cereals, nuts and even some fruits.  The presence of adults indicates infested whole grains on the premises.  All whole grain products should be examined as a possible source including stored food grains and well as decorative grains like Indian corn.  All infested items should be discarded or items treated using either extreme heat or cold.  Pheromone traps are available to determine areas of activity.  Thorough cleaning of closets, pantries, shelves and cabinets where infested items were discovered followed by crack and crevice treatment by a pest control professional using a residual insecticide also aids in control of rice weevil infestations.