From Smokey Wire member Roy Anderson, posted with his permission:
A week or so ago, I read the article linked below about wildfire in California. In the first few lines it states, “The U.S. Forest Service estimates that dead stands in the Creek fire contain 2,000 tons of fuel per acre”.
2,000 tons of biomass per acre is higher than I’m used to seeing when looking at USFS FIA Data across other parts of the US West….higher by an order of magnitude for average stands. For example, as a rough calculation, assume a stand averages 100 trees per acre and 24” DBH (pretty nice timber!). This would mean that each tree in the stand has about 150 cubic feet of volume (bolewood) or 15,000 cubic feet of bolewood per acre. Each cubic foot of wood weighs about 60 pounds (green weight), which translates into about 450 tons per acre green weight basis (100 trees/acre x 150 cubic feet per tree x 60 pounds per cubic foot divided by 2000 pounds per ton). If you double that amount (which I think is very generous) to account for branches needles and all other vegetation it still only adds up to 900 tons per acre on a green weight basis. An oven dry weight basis would be half of that. It really makes we wonder if the 2,000 tons per acre figure is accurate? If so, maybe its caused by accumulation of fuel from dead timber and other vegetation???
Anyway, I’m writing to see if you have an opinion about the accuracy of this?