A to Z of Pests

Bark Beetles

Family Scolytidae

Appearance

• Adults – 6 mm long. Mostly all black and have rust coloured wing covers.
• Larvae – 6–7 mm long. Creamy white, cylindrical, head is pale tan / rusty colour.

Lifecycle

• Males join the females and each pair construct an egg gallery under the bark, parallel to the grain.
• The sapwood is inoculated with spores of a blue stain fungus as the egg gallery is built.
• Larvae hatch, pupate and develop into adults under the bark.

Habits

• They are common pests of conifers and some attack broadleaf trees.
• Several hundred species are known.