Tree Trouble: Beavers and the Trees they Chew On

Flooding is not the only noticable impact of beavers on the human environment. Beavers are experts at removing trees and other vegetation.

• Various studies have been conducted to try to determine what beavers prefer to eat. During winter, beavers eat woody plants, and in the summer they eat mostly herbaceous materials.
• They seem to prefer willow species, cottonwood, alder, vine maple, and aspen. They seem to avoid cascara, especially the young sprouts.
• One good way to protect your plants is to decrease their palatability. An exterior latex paint colored to match the bark of the tree and applied around the base is one method used fairly successfully by several people. You might mix a little sand into the paint, too.
• Another way to decrease palatability is with an herbivore repellant called Plantskydd. It has proven effective in the Northwest, but it needs to be applied several times a year. Additionally, it is most needed during the rainy season, which is when it is most likely to wash off.
• A mechanical barrier, such as a fence, between your newly planted vegetation and the beavers has proven remarkably effective. Apparently the beavers won't go around the fence. But be careful: if this is an area with heavy flooding, it is possible the beavers can go over the fence if the water level rises above the fence.

Another resource: How to Protect Trees from Beavers (external link)