Softwood plantations are most often grown to produce fast growing softwood trees that provide softwood fiber for pulp mills. Volume and fast growing fiber is the main goal of the plantations on New Brunswick’s Crown Land. The primary species that are planted include black spruce, and white spruce, with smaller numbers of red spruce, Norway spruce, jack pine, white pine and red pine.
Plantations are expensive to produce and to tend. They are more susceptible to catastrophic insect attack than our diverse, natural forest and therefore sometimes require pesticide treatments in order to protect the investment. Plantations need to be sprayed with herbicide in order to kill competition, the pioneer species like White Birch, Poplar, Red Maple that naturally and readily grow back on these sites after clearcutting. Before the final harvest, plantations are often pre-commercially thinned and commercially thinned in order to improve the growth of the remaining trees This is all done so that the final harvest can take place after 40 to 60 years of growing time, increasing the trees growth rates and decreasing the time between harvests.
New Brunswick Crown land policy allows more wood harvesting to be conducted today than is naturally sustainable, based on the assumption that plantations will grow faster and produce volume sooner than natural Acadian forest. This assumption is, as of yet, untested, as no plantations will be ready to harvest for another decade.
Currently plantations have replaced about ten percent of our natural public forest. This amount is being allowed to almost triple.
Natural forests help stave off climate change
A recent study looked at differences in ecosystem carbon pools between plantations and their corresponding adjacent natural forests. The researchers found that plantations reduce carbon storage relative to natural forests. The total carbon stock in plantations was found to be 28% lower than comparable natural forests. This result was similar across geographic regions and between tropic and temperate forests. According to Science Daily (May 31, 2010), “this study challenges the idea that planting non-native or native-improved growth species on historical forest land yields greater carbon accumulations rates. They argue against the replacement of natural forests by reforestation, also known as plantations, to help stave off climate change.”
Chengzhang Liao, Yiqi Luo, Changming Fang, Bo Li, Andy Hector. Ecosystem Carbon Stock Influenced by Plantation Practice: Implications for Planting Forests as a Measure of Climate Change Mitigation. PLoS ONE, 2010; 5 (5).