Larva - The young, legless larva is green. Reaching a mature length of 12 to 13 mm, the grub is greenish or yellowish with a white or pink line down the center of the back and a dark line along each side. It is enclosed by a straw colored cocoon 9 to 10 mm in length. Damage - Clover leaf weevil larvae begin feeding on plants early in the spring. Infested plants become ragged as the grubs chew out small holes and irregular patches from leaves.
Damage is most severe during late, cool, dry springs.
During wet or humid weather, many larvae are killed by a fungal disease. The larvae spend the winter in the soil near the crowns of plants and emerge early in the spring, climb the plant, and feed on foliage. Full grown in April or May, the larvae spin cocoons on leaves, in soil, or among debris and pupate for 11 days. From May to July, the nocturnal weevils emerge and feed only a short time before becoming inactive. In September and throughout the fall, beetles resume activity and deposit eggs on leaves, in hollow spaces of old stems, and in cavities gnawed out of young stems.