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DEODAR WEEVIL
Chip cocoons made by mature larvae of the deodar weevil underneath the bark of an infested tree. |
Other: |
Snout beetle |
| Species |
Pissodes nemorensis |
| Common Hosts: |
Deodar cedar Cedrus deodara
Loblolly
pine Pinus taeda
Longleaf pine Pinus palustris
Sand pine Pinus clausa
Shortleaf pine Pinus echinata
Slash pine Pinus elliottii
Spruce pine Pinus glabra |
Description |
Adult - approximately 7mm long; long snout on small head; rusty red to grayish-brown head and body; 2 white spots on rear end
Pupa - similar to adult; creamy white
Larva - size variable, approximately 12 mm long when mature; amber to dark orange head, white body; legless |
| Importance: |
Trees of all ages are susceptible to weevil damage. Trees severely stressed by fire, drought, extreme cold, fusiform rust, wind damage, and other problems are prone to weevil infestation. |
| Biology and Habits: |
Adult weevils become active in fall, feed and mate, and females lay eggs in the holes made while feeding in the bark. Larvae emerge from the eggs and feed in the inner bark. The pupae occupy chambers (chip cocoons) made by the larvae. New adults emerge in spring and are inactive during the summer. |
Number
of Generations |
1 generation per year. |
Signs
of Infestation |
Foliage discoloration: needles with scorched appearance, particularly topmost branches. Small holes (approximately 0.4 mm wide) in shoots, often the most dominant branch. Shallow depressions or chambers in the sapwood with a layer of long yellowish-white wood fibers on top. |
Similar
Damage |
REPRODUCTION WEEVILS: Adult weevils larger, approximately 10 mm long; several small yellowish-white patches on body; large patches of bark removed from branches. |
Control |
Maintain tree health and vigor. Avoid mechanical injuries to the trees. Cut and remove severely infested trees. Use an approved insecticide for high-risk trees or weevil-infested trees.
NOTE: The deodar weevil is a vector of pitch canker fungus which can reduce the growth rate or kill southern pines. Any control methods should consider the disease aspect.
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Bulletin No. 196-A | Printed October, 1983 | Contact the
Forest Health Section 
