WHEN A CUTBLOCK IS LOGGED in BC, approximately 50 percent of the original living biomass is left in the clearcut as roots, stumps, unmerchantable tops, branches, part of the otherwise merchantable stem that are decayed, broken or wasted, small trees that are killed as collateral damage, the understory of plants, dead trees and course woody debris.
Of the merchantable stems that are removed as logs, what happens to them?
An unknown fraction are lost along the way, mainly by escaping from booms and/or sinking. But of those that make it to mills, about 52 percent of that volume is turned into wood chips or sawdust, according to the ministry of forests Major Mills Survey. This is used for making pulp and paper and various other short-lived products, like burnable, compressed sawdust pellets. These products account for about 26 percent of the original forest’s biomass.
The other 48 percent of the volume of logs is milled into sawn lumber or turned into veneer or panel boards like plywood and OSB. Of these wood products, roughly 80 percent is exported, mainly to 3 countries: the USA, China and Japan. These exports account for about 19 percent of the forest’s original biomass.
The lumber products that are used in BC account for less than 5 percent of the original biomass of the forest that was logged.
The diagram below is the ministry’s account of “fibre flows” that result from BC’s logging activity. Keep in mind that this only accounts for about half of the biomass that is killed as a result of logging.