Hylobius radicis

The pine root collar weevil, Hylobius radicis, is very similar to the pales weevil, H. pales. However, unlike the pales weevil, it will attack both young and older pines. Healthy, open-grown trees, such as those found in nurseries or plantations, are fed upon by this insect. Adults and larvae feed at the root crown of their hosts on the inner bark. Adults are dark brown weevils (1/3 to 1/2 inch in length) with elongated snouts and small patches of pale colored hairs on the elytra (hardened wing covers). Mature larvae are c-shaped, 1/2 inch in length, whitish in color with brown head capsules. Occassionally, adults may be found feeding on the bark of small twigs and branches in the crown at night, particularly near wounds. Adults may also move on the ground from tree to tree at night. Overwintered females emerge in May and begin egg laying, which may last through September (peak egg laying may be in or around mid-to-late June). In a feeding wound in the inner bark of the root collar is where the eggs will be laid. Occasionally, females lay their eggs in the soil just a few centimeters from a root. Females lay on average 18 eggs the first season, and 15 eggs the second. Eggs hatch and the larvae of the pine root collar weevil feed in the bark phloem. Larvae may pass through up to 7 instars (molts). A large build-up of pitch from resin flowing from feeding wounds in the outer and inner bark may be found at the base of the tree and into the surrounding soil. All life stages of the weevil are found throughout the growing season. Pupae are not formed in the typical chip cocoons created by most weevils. Instead, they form a pupal cell in the soil or in the gallery of the bark of the root collar. It may take 2-4 years for infested trees to succumb to the attack by this insect. In fact, it may take almost two years for this insect to complete its life cycle.