All you need do is go to the EPA website and search for 2014 greenhouse gas emissions....pg2 mid page...Forestry in US offsets ...11% ...that is 750 million tonnes of CO2 equivalent per year. US forest area is 60% of ours, Canada's offset is 1250. Our gross ghg is 525 to 550. There are a number of unsubstantiated claims being made by the pro carbon tax group...reason I ask you to go to sites such as US Environmental Protection Agency especially given that they are pro reduction of net ghgs.Kinda adds credibility to the above when EPA recognizes the offset.