The adult weevil is 3/16-inch long and light brown with a dark mid-dorsal line extending down the middle of the back. Adults possess a distinctive snout and readily fall to the ground when disturbed. Eggs are laid inside alfalfa stems in fall or spring. Small, light green, black-headed, legless larvae have a distinct white stripe down the center of the body. Larvae feed on the terminal and upper leaves of the plant early in the spring, reaching a quarter-inch in length in about three weeks. Larvae spin loosely-woven, silken cocoons, generally found on the ground among the leaf litter. Most damage occurs before the first cutting, but damage by larvae and adults can suppress yields by delaying regrowth after the first cutting.
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