protecting trees from beavers

Justin Jendza
​08/11/2026
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One of the main complaints that clients bring to us is that their trees are being chewed, girdled and/or felled. Frequently when we are contacted, beavers have already impacted trees and the response is reactive to this activity. Thankfully, protecting trees from beavers is a simple, if only time consuming exercise.

Beavers tend to target their preferred species, namely Populus (cottonwood and aspen) and Salix (willow). In the absence of these species, and even despite these trees being present beavers will also target maple, cherry, apple and even hardwoods like oak. Generally they don't target trees that are more than 100 feet from the shoreline, but I've seen entire hillsides of aspen up to 200 feet from the water's edge felled.

Folks are surprised at the size of trees that beavers will take down and I'm often asked just what a 60 pound beaver is doing dropping a two-foot diameter cottonwood. Well, I can tell you that if they aren't dropping it across a stream to use it as an anchor for a dam they're definitely not moving that trunk!

Beavers are interested in the cambium, the inner layer of bark that represents the living part of the tree where nutrients move from the roots to the buds and leaves and back down. When a tree is girdled, it's this layer, when it is completely separated from the cambium above and below it, that results in a tree dying. The beavers are most interested in this, and smaller branches further up the tree that have both cambium and storage capability for their winter cache. The trunk remains on the ground, often stripped of some or all of its inner bark, and the branches are hauled off and eaten or stored elsewhere.

Thankfully, trees are easy to protect and should be protected if they have a high aesthetic value, if the predominance of the canopy is dominated by species like cottonwood, aspen and/or willow, and if shoreline stabilization is a concern. The most common techniques for protecting trees involve painting trees with latex paint with added sand or fencing around the trees with galvanized fencing (chicken wire is too flimsy so 14 gauge fencing that comes in roll is most often used). Fencing should be staked to the ground with landscape stakes of 6-12" and be of galvanized steel to resist corrosion.

It can be enticing to fence off every tree, and in some cases where the trees are of high value (orchards, tree farms, etc.) this may be the best strategy. But in most cases it is best to leave some trees for the beavers to entice them to stay where they are and to encourage them to forage on the available species that will regenerate over time (coppicing, as in species like redbud) and to allow the natural processes of canopy removal and regeneration that have been occurring in the presence of beaver for many millenia to proceed.

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Willows fenced off next to a bank lodge on an engineered pond in a condominium complex in Ann Arbor, MI

An entire hillside of aspen were dropped above a 250 foot long dam that was six feet tall at the time it was visited. Maple City, MI.