|
REPRODUCTION WEEVILS
Feeding damage of seedling bark by adult REPRODUCTIVE WEEVIL. |
Other: |
1. Pales weevil
2. Pitch-eating weevil
|
| Species |
1. Hylobius pales
2. Pachylobius picivorus |
| Common Hosts: |
Loblolly
pine Pinus taeda
Longleaf pine Pinus palustris
Pond pine Pinus serotina
Sand pine Pinus clausa
Shortleaf pine Pinus echinata
Slash pine Pinus elliottii
Spruce pine Pinus glabra |
Description |
Adult - approximately 8-12 mm long; long snout on small head; light to dark brown head and body; many scattered yellowish-white patches on wings; long-legged.
Pupa - size of adult, creamy white.
Larva - variable size, approximately 8-15 mm long when mature; amber to orange head, white body; legless. |
| Importance: |
Adult weevils can cause severe damage or death to newly planted pine seedlings, especially those on or near recently clearcut logging sites. Young pine plantations are susceptible if fresh slash (debris) or windrows (piled slash) are nearby. |
| Biology and Habits: |
Adult weevils emerge from soil or leaf litter in the early spring, feed on pine seedlings, and mate. The females lay eggs in roots of recently cut stumps or severely damaged trees (fire, hail, logging). Larvae emerge from the eggs and feed in the inner bark. Cells are constructed in the sapwood for pupation. Overwinter as adults. Two activity peaks for adults: spring and late summer-early fall. |
Number
of Generations |
1 or 2 generations per year. |
Signs
of Infestation |
Foliage discoloration. Bark of seedlings removed in small, shallow patches from branches and stem. Girdling of root collar below the ground line. Buds and needles may also be damaged. Roots of stumps or dying older trees with long galleries packed with a bright reddish-orange frass (insect wastes). Insects' presence: adults feed primarily at night, inactive in leaf litter during the day light hours. |
Similar
Damage |
DEODAR WEEVILS: adult weevil smaller, approximately 7 mm long; 2 large white patches on rear end; small holes (less than 1 mm wide) in bark. |
Control |
Postpone reforestation 9 months to 1 year if logging occurred after July. This allows aging of the stumps and slash which then become less attractive to the weevils for breeding. Minimize amount of residual slash; maximize slash breakup; remove stumps. Use an approved insecticide to dip roots, spray foliage, or place granular material at the base of seedlings; or spray stumps. Do not dip roots and use granular insecticide in the same year. |
Bulletin No. 196-A | Printed October, 1983 | Contact the
Forest Health Section 
