The forests of Newfoundland and Labrador form the most eastern part of the Boreal Forest Region of North America. The forests are relatively small, primarily coniferous trees intermixed with hardwoods. The variety of species is quite limited. Due to cool, moist climates, nutrient cycling is slow and poorly drained soils have developed. Repeated fires have established Black Spruce (Picea mariana (Mill.) B.S.P.) as a characteristic species across much of central Newfoundland. Elsewhere, the forests are dominated by the presence of Balsam Fir (Abies balsamea (L.) Mill.).
The forests of the west coast are commonly pure stands of Balsam Fir which prefer moist, well-drained soils and can attain heights of 20-24 meters at 70-100 years on the best sites. Black Spruce forms about one-third of the forests on the Island and two-thirds in Labrador. Due to its very high tolerance for unfavorable conditions, this species is common on very wet and dry sites. The species grow well on fertile sites, but is a poor competitor among faster growing hardwoods. Black Spruce is found primarily in the central plateau of Newfoundland where forest fires are common; the nature of its cones gives it a competitive edge on burned over sites. White Spruce (Picea glauca (Moench) Voss) may be found on more favourable sites.
Hardwoods have not formed a major component of forest cover types in this province. However, White Birch and Trembling Aspen are significant components of mixed wood and hardwood stands on better forest sites throughout the Island, especially the deep river valleys of the Western Long Range Mountains and the Humber and Red Indian Lake watersheds. Hardwoods may reach heights of 22 meters at 80 years on moist fertile sites.