Growth is best in at least partial shade. Appears to have a competitive advantage over intolerant species only under a well-developed canopy. Balsam Fir does not reproduce where yew forms dense ground layers. It is indicative of cool and moist, old-growth conditions. Intolerant to moderate or heavy browsing by moose or deer.
Disturbances tend to exclude yew and any removal of the overstory is likely to be detrimental.
Probably easily killed by fire. Provides year round browse for moose and is an important winter food for white-tailed deer where it is available. Highly preferred by moose and white-tailed deer. Fleshy aril eaten by many birds, including ruffed grouse, and various nongame birds, such as cedar waxwings, robins, and starlings. The aril of Canada yew can be eaten by humans.