University of Illinois Extension

University of Illinois Extension

Hort Answers

Insect Damage

Pales Weevil
Hylobius pales

 
Frequency
4 (1 = rare 5 = annual)
 
Severity
4 (1 = very little damage 5 = plants killed)
 
Hosts
This insect is a serious pest in much of Illinois, especially in nurseries and Christmas tree farms. They feed on pine and spruce as well as many other conifers.

 
Plants Affected
 
Symptoms
This insect seldom bothers landscapes since there is very little breeding material left around. The adult chews small holes in the bark of small twigs and branches. Bark may fall away in the chewed areas and clear, sap globules are obvious. On large trees the chewing is usually near the end of branches. Needles and shoots beyond the chewed area often die, leaving reddish dead tips, which is considered unsightly.

 
Life Cycle
The adults feed at night and hide in the leaf litter during daylight. They over-winter as adults and emerge from late April to June depending on location. Adults may survive more than one "season" (fall through the following fall). It is not uncommon that they survive two "seasons. Adults lay their eggs in the roots of fresh cut stumps of pine trees. Larvae feed in the roots for most of the summer. They emerge in the fall after pupating in the roots of the cut trees.

 
Management
Grind out or otherwise remove the stumps of cut down conifers. If necessary use a recommended insecticide.

 
Related Resources
Home, Yard & Garden Pest Guide
Illinois Commercial Landscape and Turfgrass Pest Management Handbook
U of IL - Distance Diagnosis through Digital Imaging
U of IL - Plant Clinic