Don’t suffocate your trees

Correct root flare.

One of the most common problems we run into in the tree service business is suffocating trees. This is caused when a tree is planted too deep or when the soil level is raised around an existing tree (usually for a raised flowerbed), and the root flare of the tree is covered up.

The root flare is the part of the tree between the trunk and the roots. It is the part that actually flares out at the bottom of the trunk. An unexposed root flare alone is usually not enough to kill a tree, but it is enough to weaken the tree so that other factors such as fungus, insects or drought can finish the tree off.

When planting a new tree, always make sure that the tree is planted at the correct depth. Most nurseries and tree farms know to keep the root flare exposed when they pot trees, but always make sure the root flare is exposed at the top of the soil level when selecting your trees.

tree collarPhoto courtesy US Forest Service.

When you place the tree in its designated hole, the top of the soil around the tree should be about an inch higher than ground level. This will ensure that your tree does not sink too deep after it settles in.

If you are thinking about installing a flowerbed around an existing tree, remember not to raise the soil level. Instead, you can give the illusion of a somewhat raised flowerbed by covering the flowerbed with four inches of native rough-cut mulch. Make sure that the mulch is not covering the root flare of the tree.

When you have a tree that is buried too deep, it is imperative that you excavate the soil around the root flare if you want the tree to survive.

The safest way to excavate soil from a root flare is to use high-pressure air or water so that you don't damage the roots or the trunk with shovels or pick axes. If the root flare is buried more than four inches you can use a shovel or other digging tool to remove the larger portions of dirt, but dig carefully, and then finish the job with high-pressure water or air.

Make sure that the root flare is exposed all the way around the tree if you can. Install a barrier around the tree, when you are done, so that soil does not wash back in over time.

Trees are an important part of nature and they can provide many benefits if they are cared for properly. Make sure the root flares on your trees are exposed and you aren't suffocating your trees. Healthy trees make for happier homeowners.