This interesting video helps Illustrate how beavers eat twigs, but not wood. Beavers eat cambium, which is the actively growing part of the tree. Because it is actively growing, it is softer and edible, but once it actually turns into wood, the beavers don’t eat it. The twigs and skinny branches are completely made up of soft, growing material. Once a branch is about as thick as a pencil, the inner layer is actually wood. If you watch this beaver nibbling, you’ll see that around the 45 second ma