
It is common knowledge that beavers are herbivorous, but the extent of their herbivory is not always appreciated. A beaver’s massive front incisors, along with the muscles attached to its jaws, are designed for serious chewing. In autumn, beavers fell poplars, birches, alders, willows, maples, and many other deciduous trees, as well as a few conifers, to reach and consume the inner bark, or cambium layer. Beavers must meet their daily nutritional needs as well as cut enough trees to last them through the winter.
As spring approaches and beavers can access land, their diet changes from the woody branches they’ve been eating all winter (from the underwater food-pile near their lodge) to a diet that consists mainly of herbaceous plants, including skunk cabbage, water lily rhizomes, and grasses. During summer, beavers eat aquatic plants, ferns, sedges, and a variety of flowering plants. This beaver is eating from a large patch of jewelweed (Impatiens capensis) growing on and adjacent to its lodge.