Forest Operations
Conversion of Natural Forest to Plantations
Plantations can provide higher production and greater consistency of “piece” size and composition for such uses as lumber or pulp, however, it also represents the “all eggs in one basket” scenario considering that methods for papermaking and construction may be quite different in the future.
Plantation wood is usually less dense than “natural” wood, and may have less dimensional stability.
Perhaps the most significant concern regarding plantations is that the diversity of the planted forest is much lower than a natural forest. Timber companies often plant Black Spruce, a species normally found in poorly drained lowlands, because it is resistant to Spruce Budworm, and that its lumber properties are good. While currently there are no pests that target Black Spruce, monocultures are typically risky as a disease or pest of the planted species could result in catastrophic economic effects.
The value of plantations to wildlife can be increased if site preparation is not intensive (both physical and chemical) and if other tree species which establish themselves in the plantation (such as aspen, Red Maple, birch) are not subsequently eradicated by herbicide application or pre-commercial thinning.
Pre-commercial thinning
Pre-commercial thinning, particularly in dense naturally regenerating forest stands, can have great benefits to the stand to reach its full growth potential, and largest tree sizes.
Partial Harvests
Partial harvests are intended to increase the growth of residual trees, provide even-flow harvests, or establish regeneration for follow-up overstory removal.
Selection Harvest
True selection harvest is typically carried by removing <30% of a long-lived and stable stand types such as tolerant hardwoods on a long rotation (>100 years). These tolerant hardwoods, like Yellow Birch, Sugar Maple, and Beech, should always be partially harvested for best production and to maintain the "tolerant" (of shade) advantage.
Hemlock and Cedar should be harvested by long-rotation partial harvest only, and should not be harvested in riparian zones (near water) due to their longevity, and values for soil protection and wildlife habitats.
Red Spruce, a much longer-lived tree than either Black Spruce or White Spruce, is typically very shallow rooted, and therefore should only be treated by careful partial harvests during winter, or during the dry seasons.
Commercial Thinning
Partial harvests of Balsam Fir can be done until the stand is about 35 years old, or white spruce until about 60 years old, result in growth response to trees left behind (residual trees). Tree branches will respond to provide more crown closure and tree size will increase compared to non-treated stands. It is very important when conducting commercial thinning treatments to leave bigger trees with more live crown behind and harvest smaller trees. Well-rooted and dominant trees will show significant growth after treatment compared to the smaller trees, which often do not show good growth, and which will likely be less stable.
Shelterwood Harvest
Partial Harvest can be done between 35 and 45 years of age if the intent is to establish natural regeneration of young trees and conduct a removal of the overstory of trees (overstory removal) 10 years after the initial partial harvest (shelterwood).