A beaver consumes between 1 ½ to 4 ½ pounds of bark, twigs, tree leaves and herbaceous vegetation every day. By far the most preferred tree is poplar, or aspen, an acre of which would produce enough energy for 10 beavers for over a year. It is very amusing to watch a beaver eating the bark of branch. It holds it in both hands, and rotates the branch as it eats it, much as we eat an ear of corn. Smaller twigs are stuffed into their mouths and eaten whole. A beaver can digest only about 33% of the cellulose taken up; hence, the fibrous, wood chip-filled appearance of their scat (which is always deposited in water).