Must be suitable form class, not a cull or deformed tree. Measure the diameter of the tree and divide by two, then subtract the bark thickness. This gives the radius of the wood part of the tree. Measure the length of the core and subtract from the radius of wood to determine how much longer the core would have to be to reach the pith. Based on ponderosa pine, Jeffrey pine, sugar pine, Douglas-fur, red fir, and white fir.
Age is in years.
Total height is in feet of average dominant and predominant trees with tree age of at least 50 years.