A 92-foot Douglas-fir in a weighing lysimeter

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 rubber tubing filled with water connected to a standpipe, was placed under the soil container. A 1/32-inch change in water within the standpipe is equivalent to a weight change of 15.5 pounds or 1.89 gallons of water. The container, soil, and tree weighed 63,638 pounds