powder post beetle (Lyctinae)
Several species of wood borer infesting partly or recently seasoned sapwood (including plywood). One species is common in Britain, Lyctus brunneus. The larva reduces the infested timber to dust except for a thin outer layer of sound wood that eventually crumbles to the touch (hence ‘powder post’).
This definition is abridged from A – Z of tree terms: A companion to British arboriculture.
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