• Blum, Barton M.
  USDA Forest Service, Northeastern Forest Experiment Station
  

Balsam fir (Abies balsamea (L.) Mill.) is damaged by many agents, from butt rots to budworms. One form of damage that seems to have increased in recent years is the nipping or cutting of terminal buds in late winter or early spring. This damage is most noticeable on young growth up to a height of about 15 feet. Although Lateral buds are also cut, the cut terminals probably have the greatest adverse effect on growth. Large areas of young growth often look mowed".