Mountain pine beetle brood lying adjacent to a vertical egg gallery. Larvae construct their feeding galleries at right angles to the egg gallery. Larvae, Pupae, and Young adult are seen in their chambers (slide credited to Jose Negron).

Mountain pine beetle egg gallery. Females lay eggs and wedge them on each side of the gallery with packed frass (slide credited to Jose Negron).

The remains of a basal rotted ponderosa pine stump.  Decay can be attributed to fungus and insect damage.