Pine-mortality
Guides
Dendroctonus adjunctus
roundheaded pine beetle
Dendroctonus adjunctus, commonly known as the roundheaded pine beetle, is a bark beetle native to North America that infests and kills pine trees. Adults are 5–6 mm long with shiny, dark brown to black exoskeletons covered in hairs. The species has a one-year life cycle, with adults colonizing weakened pine trees in autumn, constructing extensive egg galleries in the cambium and phloem. Outbreaks can be devastating, killing up to 50% of pines in pure stands. The beetle is distributed across the southwestern United States and Mexico, and is considered a serious pest of commercial and wild pine stocks.