It is common knowledge that beavers are herbivorous but the extent of their herbivory is not always appreciated.  Examining their skull would tell you that their massive four front incisors (as well as the muscles attached to their jaws) are designed to do some serious chewing.  And serious chewing does take place, especially in the fall. Poplars, birches, alders, willows, maples and many other deciduous trees as well as a few conifers are felled in order to reach and consume the inner bark, or cambium layer. (The de-barked logs and branches are subsequently used to repair dams and lodges). Not only do Beavers need to meet their daily nutritional needs but they must cut enough trees to last them through the winter.

However as spring approaches and they can access land, their diet changes from the woody branches they've been eating all winter (from their winter food pile under the water) to a diet that consists mainly of herbaceous plants. Ninety percent of their time is spent eating non-woody plants, often skunk cabbage, water lily rhizomes and grasses in the early spring.  As summer progresses, they seek out aquatic plants, ferns, sedges and a variety of flowering plants. Usually it's not until late summer/early fall that their incisors are once again given a good workout.

The pictured Beaver had the good fortune of having a large patch of tasty Jewelweed (Impatiens capensis) growing on and adjacent to its lodge.

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