By: Mary H. Dyer, Credentialed Garden Writer
While it’s frustrating to notice signs of beaver damage to trees, it’s important to recognize the importance of these wetland creatures and to strike a healthy balance. Read on for some helpful tips for protecting trees from beaver damage.
It’s taken a long time, but beavers are making quite a comeback after an unregulated fur trade decimated numbers across much of the country, driving the animals nearly to the point of extinction. It’s important to note that beavers are extremely beneficial residents of riparian environments, helping the ecosystem by controlling floods, improving water quality, and providing habitat for plants and animals.
Unfortunately, if you own waterfront property, beavers may be creating havoc with trees in your landscape. Beavers are ingenious animals and they can come up with a lot of clever ways to get to desirable plants and trees, often taking advantage of their teeth for extra leverage. While they prefer trees within 50 feet (15 m.) of water, they are often willing to travel 150 feet (45 m.) or more from the water’s edge, especially if food is scarce.
Freshly cut trees are the most obvious signs of beaver damage, and beavers are smart enough to drop the tree in exactly the right direction almost every time. Beavers have huge, sharp teeth that enable them to take down a small tree in a matter of minutes, but larger trees take a bit longer to gnaw.
Beavers also break off branches for dam building, and they may eat the inner layer of bark, known as the cambium layer.
Circular cages or wrapping trees with hardware cloth works well for individual trees but may be impractical if you have a lot of trees on your property. If this is the case, consider protecting the most valuable trees first. Chicken wire is okay in a pinch, but a sturdier wire will last longer and offer more protection. A cage measuring 3 feet ( a little under 1 m.) tall is ample in most climates, but 4 feet (a bit over 1 m.) is better if you receive much snow. Allow about 6 inches (15 cm.) between the tree and the cage.
Fencing may be better if you need to protect a larger area, especially if the fence is placed to divide the trees from the water. If beavers are inclined to tunnel under the fence, you may need to block their tunnels with concrete blocks. An electrified wire created to keep dogs inside a fenced yard may also offer protection.
A mixture of exterior grade latex paint and sand may keep beavers away from established trees, but the combination may be harmful to young trees. This method of beaver tree damage prevention may be worth a try, as beavers apparently don’t appreciate the feel of grit in their mouths. Paint the trunks to a height of about 4 feet (1 m.).
Repellents aren’t usually effective, although they may buy you a little time while you’re devising other methods of protecting trees from beaver damage. Try various types of big game repellents.
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Beavers are one of the more intriguing creatures in the animal kingdom, as they are one of the few to actively modify their environment to suit their needs. Felling trees to dam a waterway creates the shallow ponds and wetlands that favor some of their preferred food sources. They eat the inner bark of trees and will haul the small branches to an underground cache that they feed on through the winter months. If a tree has been damaged by a beaver, but not killed, it may be possible to save it, providing that further damage can be prevented.
Remove the lower limbs and branches from the tree. This is helpful to provide better access to the trunk to inspect the wound, but also allows more sunlight and air circulation around the wound which aids the healing process. Removing limbs also benefits a damaged tree because it has less leaf surface to lose water through and less plant tissue to provide nutrients to -- meaning it can concentrate more of its energy on healing the damaged area. The limbs can be removed up to a third of the height of the tree.
Trim any rough, jagged bark that may be present along the edges of the damaged areas with a sharp utility knife. The exposed surface area of the shredded bark is more attractive to disease organisms than a smoothly cut surface and should be removed. Clean up the outer bark in this way, but be careful not to cut through into the living tissues of the tree. The tree will naturally form a "callous" of tissue over the damaged area. Other than smoothing out the cut bark, it is better not to interfere with the natural process, focusing on supporting the overall health of the tree instead.
Fertilize the tree with a balanced, all-purpose fertilizer, such as 10-10-10. This will promote healthy new growth, which means the tree will have more energy to fight infection and develop the "callous" tissue quickly. Only apply the fertilizer during the period of active growth in spring, summer and fall. Apply 1 pound of fertilizer for each inch of trunk diameter, measured 4 feet above the ground, and repeat every six to eight weeks until the end of the growing season. Also, make sure the tree does not suffer from water stress while it is recovering from beaver damage -- water once each week during the growing season unless there has been a soaking rain.
Protect the tree from future damage with a small cage of 36-inch tall hardware cloth. Drive four light-duty 4-foot "T" posts into the ground about 6 or 8 inches from the tree to a depth of 12 inches, using a sledgehammer. Using wire cutters, cut a piece of hardware cloth to encircle the tree and attach it the posts, using the metal clips on each post.
Trapezoidal protective fence installed after re-opening dammed culvert
Beavers can dramatically alter the environment in which they live through damming. Damming of road culverts, both at the mouth and inside the pipe, often results in flooding and can cause serious damage. Techniques used to mitigate the flooding damage caused by beavers include breaching of beaver dams, protecting road culverts with fences or guards, and controlling water levels with water flow devices. Whenever possible, methods that maintain the functions and values of the wetland habitats should be implemented first.
All these techniques require a significant amount of effort and regular maintenance to ensure desired water levels.
Initial costs to install and maintain culvert guards/meshes or water flow devices are typically less than the costs to repair roads, property or buildings damaged by flooding. Recognizing chronic or potential problem sites and taking proactive preventive measures may be more cost-effective in the long run.
Dam construction by beavers is an instinctive behavior caused by water-flow sensation and the sound associated with running water that stimulates dam building activity. Culverts, especially ones made of metal, will resonate the sound of the water rushing through them. When installing new or replacing old culverts it is recommended to go with the largest diameter smooth wall plastic culvert possible. Smaller culverts are much more susceptible to being blocked by beaver. Plastic culverts reduce the noise level and the smooth walls make removing any dam material much easier. Beavers will commonly block road culverts with sticks, mud, and rocks. Culverts blocked from the inside are difficult to clean and potentially dangerous. The use of meshes and grills, placed on both the upstream and downstream ends of the culvert, can prevent beavers from entering (but also increase the risk of floating debris catching on the grill restricting the flow into the culvert).
See the following steps and illustrations for potential solutions:
(NOTE: All of the following require at least annual (and sometimes weekly) maintenance in order to continue to function appropriately)
There are times when people wish to protect valued trees from being cut down by a beaver. Fortunately there are ways to protect particular trees without eliminating the beaver and the wetland ecosystem it creates. Most of the following tree protection techniques are inexpensive, reliable, and relatively easy for nearly any homeowner to do in a short period of time.
Various styles of fencing can be used to protect individual specimen trees or a small grove of trees.
Individual trees can be spared from beaver gnawing by placing wire cylinders around the base of their trunks. The purpose of the heavy wire cylinder is simply to keep the beaver from getting to the tree. This is our preferred method to protect trees from beaver chewing. The technique is 100% effective, it only takes a few minutes per tree, is inexpensive, and it will remain effective for many years with no maintenance!
Since beavers use trees for food and building materials, fencing their preferred trees (such as aspen, poplar, cottonwood and willow) cuts beavers off from these needed supplies. This can make the habitat area less inviting for beavers.
The tree trunk fence cylinders are best made from 2″ x 4″ mesh. Chicken wire often rusts out in a year or two, and hardware wire mesh is very noticeable and not very aesthetic. Various length rolls of the 2” x 4” wire mesh can be purchased at any home supply store. The fence height should be a minimum of 30 inches. In cold climates make sure the fence height is 2 feet above the highest snow level to prevent winter tree chewing. Often you will have a choice between galvanized, green or black vinyl coated fence. All work well, so for aesthetic reasons choose the color that best matches the color of your tree trunks. The initial gleam of the galvanized fence quickly fades to a nice dull gray patina which is barely noticeable on most trees.
In addition to the correct height fence, you will need a pair of wire snips and gloves. Wire fasteners or small zip ties are optional.
With simple wire snips cut a length of fence long enough to encircle the tree trunk while leaving a 3 – 6 inch gap between the wire mesh cylinder and the tree trunk. This gap allows for future trunk growth without girdling.
Position the cut piece of fence around the tree trunk and use each of the wire prongs to fasten the sides of the fence, completing the fence cylinder around the tree trunk. Other fasteners (e.g. hog rings, zip ties, etc.) can also be used to fashion the cylinder.
The cylinder generally does not need to be anchored to the ground.
You can cut the bottom of the cylinder to fit a sloping ground, or to protect prominent roots from chewing.
Replace the fence cylinder if it’s corroded or if room for more tree trunk growth is needed.
Protecting a Grove of Trees
Sometimes a person may wish to protect an entire stand of trees without wrapping each trunk individually. In this case a grove a trees can be protected by encircling all the trees with a fence. However, because beavers are good diggers, the entire fence needs to be installed in contact with the ground so that there are no gaps the beavers can exploit. In cold climates it needs to be 2 feet higher than the winter snow. Some people have reported success with leaving the side furthest from the water open. See diagram.
The fence can be simple 2” x 4” mesh secured on posts and/or against the tree trunks. However, often a roll of fence can be difficult to contour to uneven terrain.
To deal with uneven terrain or for a more aesthetic look, some people have reported good results using an electrified fence placed 4” above the ground. These electric fence kits are often solar powered. They are commonly used by farmers and are usually available at farm supply stores. The electric fence is less noticeable than a large fence enclosure, which is good aesthetically for areas with high visibility. However, an electric fence needs to be inspected periodically to ensure that a tree branch doesn’t fall on it and short it out.
Abrasive Tree Paint Protection
Many people have used an abrasive paint mixture to deter beaver tree chewing with great success. This is also the most aesthetic tree protection method. However, it is may not be 100% effective as is the tree wrapping technique.
Make 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 (2 feet above snow). Do not need to reapply for several years. Consider leaving some trees unpainted for beaver food. This formula does not work for saplings, so protect them with wire fencing.
Cayenne Pepper and Oil:
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.
Disadvantages: It has been reported by a VT state official that applying this mixture has killed thin barked trees. May need to reapply annually.
Trees and Beavers
Why Do Beavers Cut Down Trees? Beavers use the trees they cut down for food, and they use the left over branches for building materials for their dams and lodges.
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.
It’s hard to believe that beavers are able to chew right through the trunk of a tree, but they do. Beavers have very strong and sharp teeth which are paired with powerful jaw muscles. A single beaver can fell a medium sized tree in a single night! Beaver teeth never stop growing, so it is believed that beavers need to constantly chew wood to prevent their teeth from growing too long! Amazingly, due to a hard orange enamel on the front side of their incisors and a softer white dentin on the backside of these teeth, their teeth are self-sharpening as they chew on wood. As beavers chew the softer backsides of the incisors wear faster, creating teeth with chisel-like cutting surfaces. They also have molars which they use for grinding their food.
When a beaver cuts down a tree it wants to eat the inner, growing (cambium) layer of the tree bark. That is why they will nibble all the bark off the branch, leaving a debarked stick. They will also eat the fine twigs and leaves. However, they do not eat the inner woody part of the branches and tree trunk as they are unable to digest the wood. Once the bark is all eaten from a branch, they reuse the stick to build their lodges and dams. A beaver’s diet consists solely of vegetation. They do not eat fish or any non-plant materials. The reason they topple trees is to gain access to all the bark on the tree as well as the smaller twigs and leaves. 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 because the bark is thinner and easier to digest, but they can topple any size tree.
Beavers have a definite preference for the trees they like to eat. Preferred tree species include alder, aspen, apple, birch, cherry, cottonwood, poplar and willow. Aspen/poplar and cottonwood are their favorite. If the supply of their preferred trees is low they will harvest oaks and some maples. Conifers such as pines, hemlocks, etc. are their least favorite. Sometime they will girdle (remove the bark around the entire base) of conifers for an unknown reason. One possibility is to obtain some needed dietary nutrient.
If you live in a cold weather climate you may notice that beavers cut down the most trees in the late fall. This is because they are stockpiling a food cache of sticks for the winter. Beavers do not hibernate, so they plan ahead and store a large cache of edible sticks underwater near their lodge in order to be able to eat once the ponds freeze. Once the pond is frozen over and they can no longer access new trees, they will swim out of their lodge, grab an underwater stick, and bring it back to the comfort of their lodge to eat the bark.
Beavers are well adapted to water and evolved over millennia to use water as a defense from predators. While surprisingly fast over short distances, beavers nonetheless do not like to travel too far from the water to cut down a tree. Most trees that beavers cut down are within 100 feet of the water. As beavers deplete the supply of food trees close to the pond’s edge they will usually raise the height of the beaver dam to bring the pond closer to more distant trees. Another engineering trick beaver will employ is to excavate canals from the pond in the direction of the trees they wish to harvest. Once a tree is toppled they are able to cut off and transport the branches easier and more safely to the pond using their canal. Beaver are truly “Nature’s Engineers”!
The sight of dead, flooded trees (snags) seems very destructive and ugly to most people. However, snags are needed by many species of birds. Swallows, wood ducks, blue herons, eagles, osprey, woodpeckers, turtles 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 a necessary and extremely important habitat to many other species in the ecosystem.
The loss of these trees also allows significant more sunlight to reach the water. The sunlight, water, and suspended nutrients in the pond water combine to stimulate the immense growth of algae, microorganisms, invertebrates and aquatic plants that then become the foundation of the wetland food chain. These life forms become food for innumerable larger species and create a prolific biodiversity of species in and around a beaver pond. Beaver ponds are seven times more bioproductive than the most fertile farmland. They become magnets for wildlife. So at first glance the death of these trees appears to be a destructive act by the beaver, but it is actually an absolute requirement to support the abundance of life that makes these wetlands so valuable.
Tree protection also modifies the habitat by decreasing the beaver food supply. The more trees that are protected the sooner the beavers will exhaust their food supply. Eventually they will relocate but it often takes years. Trapping the beavers preserves the food supply and will keep it attractive habitat indefinitely. In our experience trapping is a short term solutions as new beavers often relocate to the trapped habitat every year.
Once an area is depleted of their preferred trees it won’t become good beaver habitat for another 10 – 15 years until new trees are large enough to provide adequate food.
Wrapping the trunks of trees with fencing not only protects the trees from chewing, but also modifies the habitat by decreasing the beaver food supply. The more trees that are protected the sooner the beavers exhaust their food supply and will relocate. The area typically won’t become good beaver habitat for 10 – 15 years until new trees are large enough to provide adequate food. This is a longer term (and less expensive) option if there are limited number of trees to protect. There is more information about tree protection on our website.
Need beaver removal in your hometown? We service over 500 USA locations! Click here to hire us in your town and check prices - updated for year 2020.
While there is no spray or powder that will keep the beavers away from an area, you can apply Thiram to plants to prevent beavers from chewing. And while only a stout fence will keep them out of a creek or pond, you can install a beaver drain pipe to lower the water levels.
Beavers are a type of pest that will destroy a lot of vegetation and trees. Their damage can actually be a lot more than problematic as far as looks go, it can be dangerous. You are more likely to have a beaver problem if you live close to a body of water such as a pond, lake or river. They will build dams that they use as shelter and those dams can cause problems with drainage. Depending on the number of beavers that you have in the area the damage can go from mild to severe, so you as a home owner want to find ways to get them to leave the area at least be far enough that they do not cause any damage to property. Fortunately there are a few things that you can do to get the aquatic rodents to get a new place far from your home.
Sand And Paint
This is a quick way to get the beavers to move. It is cheap and effective and anyone can do it after visiting a home improvement store. Get some latex paint and sand which you will mix together to use as the repellent. Once the ingredients are well mixed it is time to get to the painting part of the process. You will use this mixture to paint the trees around the area that a beaver may be working on. Paint about 4 feet from the root up. Paint all trees not just the older ones. When a beaver does not get the materials it needs from the older tree, it will collect it from the younger ones that you would not even think it could. Let the paint settle for a day and then repeat the process. You may need to reapply the paint after a few weeks depending on the weather in your area.
Other than the latex paint and sand solution you can also go with fencing of the trees and gardens. This solution can be a bit more expensive, but it is also effective and it means that you do not have to keep painting the trees around the area. The fencing is effective when the fence is made of metal. Metal rods and chain link are a perfect combination for fences if you want to keep the beavers away. You should make sure that the fence is high enough to discourage the beavers and it should also be buried about a foot down. The decision you make regarding paint or fencing is a decision on what you would rather have the trees in the area look like. The fencing option is one that will last longer and you will not have to care for as often as you do the paint, but the price is lower with the paint option.
Short of repellent the only other option that you have that is effective is to trap the beavers. You can choose to do so yourself, or you can hire a company to trap the beavers for you. The benefit of trapping the beaver is that you can be certain that they will be moved to another location as opposed to having to deal with them every day. There are live traps available to get the beavers in a humane way. You should also look up the laws regarding wildlife trapping in your area. If there are laws that prohibit the trapping or that require a license to do so then you can face fines. A wildlife trapper would know the requirements and would more than likely relocate the beaver to a new location. Whichever option you choose you should know that getting rid of beavers is not impossible and it can be done in a humane manner.
Information about beaver trapping - analysis and methods for how to trap.
Sprays And Pellets
There are also several different types of repellents that you can get from the store to help to deter beavers from an area if they havenвЂ™t already started to inhabit the spot. These can generally be purchased at a local hardware or garden store. Some of these are sprays that you can use solo, some attach to hoses and others are meant to sprinkle in the surrounding area. Be sure to read the directions and precautions carefully as they may be harmful to pets or children.
Information about how to kill a beaver - with poison or other methods.
Information about how to keep beavers away - prevention techniques.
Information about how to catch a beaver - remove one stuck in the house.
This site is intended to provide beaver deterrent education and information about beaver repellents, like sprays for trees, such as those you can buy at Home Depot or Lowes, so that you can make an informed decision if you need to deal with a beaver problem. This site provides many beaver control articles and strategies, if you wish to attempt to solve the problem yourself. But remember, mothballs and fox or coyote urine won't do the trick, nor will high pitch sound or noise machines. If you are unable to solve the problem on your own, which is likely with many cases of beaver removal, please go to the home page and click the USA map, where I have wildlife removal experts listed in over 500 cites and towns, who can properly help you with your nuisance beaver.
Click here to read more about how to get rid of beavers.
Fencing to Protect Trees from Chewing
Beavers chop down trees with their teeth for food and building dams and lodges. In addition, like all rodents their teeth never stop growing so chewing wood helps keep them sharp and prevents them from growing too long.
Protecting trees from beaver chewing is a very common concern for homeowners. Fortunately there are ways to protect selected trees without destroying the beaver and its wetland ecosystem.. Most of the following tree protection techniques are inexpensive, reliable, and relatively easy for nearly any person to do in a short period of time.
The beaver is the largest North American rodent. They may grow to 100 pounds, although the average is 35 to 50 pounds, and are suited to life in the water, with webbed feet and a large, flat tail. Beavers are territorial and live in colonies of four to eight related animals, near a year-round source of water. They are famous for their dam building skills used to create their own permanent pond by damming up streams. The beaver is making a comeback in many areas where they have been absent for decades because of development. They now frequently live in sediment control ponds in the middle of housing developments. Beavers feed at night primarily on woody plants although they will also eat herbaceous plants and aquatic plants. They become troublesome to homeowners when they girdle or cut down landscape trees, or when their dams cause flooding of roads or other property. Some of their favorite species are black gum, sweet gum, willow, pine, and maple. Entire trees can be brought down by beavers' chewing through the trunks.
Homeowners must put metal barriers of welded or woven wire fencing material around valuable trees to protect them from beaver damage. Landowners can install various structures in the dam to maintain the water at a certain level. These devices often consist of a perforated PVC pipe that is encased in heavy gauge hog wire. Fencing to exclude beavers from a pond is not very effective. When beaver populations become too large and routinely destroy landscapes it will be necessary to contact County Animal Control or the Dept. of Natural Resources.
|Beavers are famous for their dam building skills used to create their own permanent pond by damming up streams. (lodge and dam in photo)||Tree felled by beaver.|
|Damage to a fairly large shade tree.||Homeowners must put metal barriers of welded or woven wire fencing material around valuable trees to protect them from beaver damage.|
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