Hiker's Guide to the Trees, Shrubs
and Vines of Ricketts Glen State Park

Ragged Spruce Gall Adelgid
(Pineus similis) on Red Spruce

Reference: Johnson, W.T., and H.H. Lyon. 1976. Insects that Feed
on Trees and Shrubs.
Comstock: Cornell University Press.


Updated 10 October 2018.