Trees are great additions to any property—they beautify your outdoor space, provide shade, and increase the value of your home. But trees are also huge, heavy things sticking out of the ground right next to your home, and if one of them decides to fall over and hit your house, the damage can be substantial. Removing the tree and fixing the damage can be expensive—just removing the tree costs an average of $850, and if the tree causes structural damage to your home the costs can quickly get out of hand. Worse, there’s no guarantee that your homeowners insurance will cover those costs, especially if it’s determined that the tree fell due to negligence.
So tree falls can be expensive, and even deadly (more than 400 people were killed by falling trees between 1995 and 2007, according to one study). While most tree falls occur during inclement weather, one of the biggest factors is the health of the tree and its roots. Luckily, your trees will show signs of failure that can give you plenty of warning, giving you an opportunity to have the tree examined and possibly removed before it ruins your day by falling on top of you. Here are the signs to look for.
A clear sign that a tree is in poor health and in danger of falling is its branches. If the tree has a lot of dead branches, or you find dead branches on the ground around it on a regular basis, it’s time to contact an arborist to have the tree examined thoroughly. Dying branches can indicate a dying tree—and even if your tree can be saved, you’ll still need to prune off any dead branches before they fall and potentially cause damage or hurt someone.
Does your tree have bald spots? If your tree has several “cankers”—spots where the bark is missing, leaving what looks like a gash or indent in the tree—the tree may be weakened enough to fall. Cankers and missing bark are usually caused by bacterial or fungal infections afflicting your tree, and these infections can eventually undermine the structural integrity enough to cause it to fail and fall.
Speaking of fungus: Look at the base of your tree. If you see a bunch of mushrooms growing there, that should raise a red flag, because mushrooms feed on trees. Seeing mushrooms anywhere on your tree is a sign that the tree is stressed and needs some attention, but mushrooms at the base indicate that the fungus is eating the tree’s roots—which will eventually kill and destabilize the tree, making it much more likely to fall over.
Are your tree’s roots showing? If you can clearly see the roots of the tree above ground, your tree is in trouble. While a healthy tree can suffer exposed roots (they can be the result of soil erosion, for example), whatever the cause, it’s a sign your tree is no longer deeply anchored in the ground. If the problem worsens, your tree can literally lose its grip in the dirt and topple over.
You should also look for cracked soil at the base of the tree—the roots may not be exposed yet, but if you see the soil cracking and pushing upward it could indicate that the roots have begun to lift, and that means the tree has begun to fall.
If you see large black ants crawling around your tree and little piles of sawdust on the ground around it, your tree has likely been invaded by carpenter ants. Carpenter ants are not direct threats to your tree—they are instead a sign that your tree is already unhealthy, because rotten sections of wood and holes give them access to the tree in the first place. You can get rid of the ants, but you should also have your tree examined to figure out what the real problem is—and whether it’s putting your house at risk.
If the trunk of your tree is split by a large crack, or if you can see large cavities in the trunk (literally deep holes in the body of the tree), the tree may be in danger of falling. A cracked trunk is beginning to split, meaning that the structural integrity of the tree is eroding, and it will eventually become weak enough to fall over. Cavities can be caused by a range of things (like animals making nests or hunting for bugs) and don’t always indicate an unhealthy tree, but if you see more than one or if the cavity is especially large, it could spell doom for the tree.
It’s a bit obvious, but worth noting: If your tree has recently developed a notable lean, it’s in danger of falling over. A leaning tree indicates that the roots are no longer holding it firmly in the ground, and can be caused by severe winds or loose soil. It’s possible to straighten and save a leaning tree, but only if the tree is otherwise healthy—if it’s leaning because the roots have rotted or because the tree is diseased, straightening it won’t solve the problem.
