Tree Protection from Beaver Chewing

Despite the importance of these wetlands and the death of many trees, there are times when beaver and humans value the same tree(s), but for different reasons. When this happens many people may wish to protect certain valued trees from being cut down by a beaver. Fortunately there are ways to protect particular trees without eliminating the beaver and it's wetland ecosystem. Some of the following methods have been tried with great success. They are inexpensive, reliable, and relatively easy for nearly any homeowner to do in a short period of time.

With sharp incisor teeth and powerful...

Individual trees can be spared from beaver gnawing by placing wire cylinders around the base of their trunks. The purpose of this heavy wire cylinder is simply to keep the beaver from getting to the tree. The cylinders can be made from 3 to 4 foot tall galvanized garden fencing (2" x 4" mesh).

Notes

The fencing should extend 2 feet above the highest snow level to prevent winter chewing. It generally does not need to be anchored to the ground. Cut the bottom to fit a sloping ground, or to protect prominent roots from chewing. Leaving a few inches of space between the tree and the wire allows for tree trunk growth. Replace as needed with a larger diameter cylinder to allow for trunk expansion.

Abrasive Tree Paint Protection

Ingredients

1. Paint: Exterior Latex (choose a color to match the bark)
2. Mason Sand (30 mil or 70 mil)
3. Formula Mix 5 oz sand per quart of paint, or
4. Mix 20 oz sand per gallon of paint, or
5. Mix 140 gm sand per liter of paint.

Note

Make only in small batches at a time on the day you are going to apply it. Using too much sand will cause the mixture to roll off the tree. Apply paint to bottom three to four feet of tree trunk. For best results, do not paint every tree, leaving some for beaver food. This formula does not work for saplings, so protect them with wire fencing.

Above method reprinted from the Wildlife 2000 Newsletter, 2000 News edition, p.3.

Another Method of Protecting Trees

Cayenne Pepper: Vegetable or mineral oil infused with cayenne pepper and then painted on the tree trunks has also been reported as an effective means of preventing beaver chewing.

Acknowledgements: Dr. Thomas E. Eveland, Ecology Consultant, The Fund for Animals and the "Beaversprite" newsletter.

Trees and Beavers

Beavers are famous for their ability to topple large trees using nothing but their specially adapted teeth. Beaver teeth never stop growing, so they do not become too worn despite a lifetime of chewing hardwoods. Their four front teeth (incisors) are self sharpening due to a hard orange enamel on the front and a softer dentin on the backside of the tooth. Therefore as beavers chew wood the softer back of the teeth wear faster, creating chisel-like cutting surfaces. Because their teeth never stop growing it is believed that beavers need to constantly chew wood to prevent their teeth from growing too long!

A beaver's diet consists solely of vegetation. They derive nourishment from the inner lining of tree bark, as well as twigs, leaves, and aquatic vegetation. They topple trees in order to gain access to all the bark on the trunk as well as the many branches on the tree. Branches will be chewed off in sections that are small enough to drag into the water for safe and leisurely eating. The bark of large tree trunks will be chewed where it lies if the beaver can reach it. Beavers prefer to cut down smaller diameter trees, but will chew on any size or species of tree. Preferred tree species include alder, aspen, birch, cottonwood, maple, poplar and willow. Once beavers eat the bark off a branch, they reuse the stick to build and maintain their lodge or dam.

A beaver snacking on the bark...

In cold weather climates beavers are most active cutting down trees in the fall because they are preparing for the winter. Beavers do not hibernate, so they plan ahead and build a stockpile (cache) of edible sticks in order to survive the cold winter. They stick one end of these sticks in the mud at the bottom of their pond near their lodge so that when the pond freezes over and they can no longer access new trees, they can swim out of their lodge, grab a stick, and bring it back to the comfort of their lodge to eat.

Beavers usually do not cut down all the trees in their ponded areas. Some of the trees remain standing but die due to elevated water level. While to many humans these dead trees (snags) are ugly, they are needed by many species of birds. Swallows, blue herons, eagles, osprey, woodpeckers and many others rely on these dead trees for food, shelter and places to perch. The death of trees may look destructive and unattractive to us, but they are necessary and extremely important to many other species in the ecosystem.

The loss of these trees also allows significant more sunlight to reach the water. The sunlight and water, combined with the nutrients that the pond retains is this foundation of the wetland food chain by promoting The resulting growth of plants, algae, microorganisms and invertebrates is the basis of the food chain and supports the prolific biodiversity of these ecosystems. Beaver ponds are seven times more bioproductive than the most fertile farmland. So while at first glance the death of these trees appears to be a destructive act by the beaver, it is actually an absolute requirement to support the abundance of life that makes these wetlands so valuable.