Extension > Garden > Diagnose a problem > What's wrong with my plant? > Evergreen Trees and Shrubs > Spruce > Frass on trunk
Spruce > Trunk or branches > Frass on trunk
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Northern spruce engraver beetle
Ips perturbatus
- Reddish brown frass around exit holes and on the bark and on the ground
- Found mostly on white spruce in plantations, rarely in home landscapes
- Needles discolors to yellowish-green to red, branches can die back
- Creates distinctive galleries under bark
- Adult
- More information on Northern spruce engraver beetle
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Spruce beetle
Dendroctonus rufipennis
- Found in stands white spruce in northern Minnesota, particularly along the North Shore
- Prefers larger trees, 12 inch diameter trees or larger
- Needles discolor yellowish green to reddish brown
- Reddish brown sawdust around exit holes and on the bark and on the ground
- Pitch tubes develop around exit holes
- Trees eventually die
- Adult beetles are 1/4 inch long and black to reddish-brown; larvae are small, white legless grubs
- More information on Spruce beetle
