Elm Borers and Elm Bark Louse : Elm Borer (Sapreda tridentata Oliv.). 1. Larva or grub within its burrow just under the bark; 1a, Larva or grum extended; 2. Pupa within its cell just under the bark; 3. Burrows of the grub as exposed after removal of the b

Freshwater and Marine Image Bank, University of Washington Libraries Digital Collections