Fritschen, Leo; Cox, Lloyd; Kinerson, Russell S., 1941-; U.S. International Biological Program. Coniferous Forest Biome; University of Washington (Seattle : University of Washington, 1971)
A soil container 12 feet in diameter and 4 feet deep was constructed around the root ball of a 92-foot Douglas-fir tree in a naturally regenerated stand. The weighing mechanism, consisting of 550 feet of
2.5-inch butyl ...