How to wire trees to protect against beavers
Hi, my name is Tanya Hope and I’m a Parks Ecologist with the City of Calgary. And my name is Chris HIcks and I’m an Environmental Education Program Advisor with the City of Calgary. We’re here today to tell you about wiring trees to protect against beaver damage. Beavers are an important part of our urban ecosystem for several reasons. Their dams help protect against mild flooding. Their dams also save water during droughts and they create other wetlands for wildlife within our urban ecosystem So while we really want them in our city we also recognize that beavers can do a lot of damage. An adult beaver can chew up to 200 trees per year. If you have a home on the Elbow or Bow River with property adjacent to the river, you may have trees that are suffering from beaver damage. So today we’re going to show you how to wire those trees. We ask that you do not wire on public lands as we need to know where those trees are wired so we can monitor them for their health so they don’t get girdled. And we also don’t wire all of our trees in our natural areas because we want to leave some for the beavers to ensure that they stay in our city. If you have any concerns about beavers, please contact 311. So I have my safety goggles and gloves which are important to keep you safe and here are some of the other tools that we will use today. We need to measure the width of your tree. You can use a measuring tape but flagging tape or rope works just as well. We also have our wire cutters. There’s two different kinds. These are your standard wire cutters. These are a bit more hefty. And finally our zip ties. We use four inch zip ties, but you can use ones that are larger. Please make sure that they’re good for outdoor use. We want to make sure that they last around the tree. So the most important tool you’ll be using today, of course, is the wire. Now you’ll notice that this wire is pretty heavy duty. It is stucco wire but it has the one inch squares. We’ve noticed in some of our parks that with the two inch squares, the beavers are able chew through the tree and actually knock it down. You’ll also notice that the width of the wire, or the gauge, is quite strong. It’s usually between 12 and 16 gauge wire. Now a lot of people will put chicken wire or really thin wire around the trees. That really doesn’t slow or stop the beavers down. So while this wire is a bit expensive it’s worth it to save our trees. We’re going to teach you how to measure a tree. We’re using the orange flagging tape. Tanya’s going to walk around the tree. We normally measure it around breast height because that’s usually the widest part of the tree. We do want to look around the base to see if there’s any bumps or wider parts when we’re measuring. Then we usually take an arms length of extra space just to give the tree room to grow. Now that we’ve measured the tree, I’m going to show you how to cut the wire. This part can be a bit tricky and a bit dangerous. So, I’m going to go through it step by step. First I’m going to have Chris stand on the edge of the wire and put the flagging tape underneath his foot. Then I’m going to take the wire and carefully roll it out. As you get closer to the centre of the roll, this will become harder and the wire won’t move as easily. Once you reach the end of the flagging tape, you can put it down on the wire. If you have a third person, you might want to have them stand at the end of the roll so it doesn’t re-roll. But since we don’t have someone, I’ll definitely keep my foot there as I cut. No, we’re going to keep our gloves on. Get our wire cutters out. Go back from the wire cutter and start to cut our wire. Try to cut it as close to the one side as possible. As you start cutting, you’re also going to want to put your other foot on the other side of the wire. Now that you’ve cut through the wire, you’re going to very carefully remove your one foot from the end of the roll. Before you move your other foot, grab on to the wire and roll it back up. Now that Tanya’s cut the wire, we’re going to show you how to wrap it around the tree. I’m going to hold this side while Tanya walks around the tree. She’s going to met me on the other side. Once she gets here, we’re going to make sure the sharp edges are on the inside of the wire. I’m going to hold it together and Tanya is going to zip tie it together. Make sure you zip tie at the top, the middle and the bottom. And you usually try and overlap two squares so the diameter is what you measured it out to be. Now that you’ve wired your tree you can see that there’s room for it left to grow. Bigger, older trees won’t grow as much in a year as a smaller, younger tree. We recommend that you check your trees about every five years to make sure they are not girdled. If you find that your tree has wire growing in it. We ask that you don’t pull the wire out. Tree have only one chance to heal and it’s already healed around the wire. Cut as much wire away as you can and rewrap the tree. We showed you how to wire a tree that’s on flat ground. But a lot of you living along the riverbank will have a slope behind your property. As you can see, the wire isn’t sitting flat on the ground. The goal of this is to prevent the beavers from chewing the tree. The beavers can go underneath the wire and chew on the tree. We’re going to show you a quick tip on how to prevent that. First, make sure the part that you close is facing away from you. Now cut a U shaped out of the bottom of this wire so it sits flat against the slope. We’re just going to eyeball this. Don’t worry if you don’t get it exactly right. The part that you cut out you can add to the other side of the tree as a bit of a bib. We’re cutting up on a diagonal to start. And then we’ll go across. About the width of the tree. Now we come back down to the other side. We’ve cut out a U shape. And if you turn the wire, it’ll sit flat against the bank. You may need to do some adjustments here so you can see we might want to go a little bit deeper. Just play around with it until you get a good fit. Then, if you need to, you can always add this part to the front to prevent the beaver from coming up underneath.