Possible beetle feces

Unidentified frass. Sonora California. 12 October 2017. Collected from basement, by Josh Esposito.

Dr. Andrew Sutherland thinks, but is far from certain, that this is feces from a developing beetle larvae, given the varying size. They are very similar to frass collected from a drawer that had powder post beetles. See https://foothillpest.com/technical-pages/frass-images/beetle-frass-from-drawer/

 

holes are about 1/8 inch diameter
holes are about 1/8 inch diameter
Frass visible inside exposed lumber
Frass visible inside exposed lumber
Frass visible inside exposed lumber
Frass visible inside exposed lumber
Exit holes
Exit holes

Millimeter scale. frass about 0.75 mm in length.
Millimeter scale. frass about 0.75 mm in length.

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