Recently I have had several older trees suddenly exhibiting signs of serious stress. They aren't suffering from a disease, but instead I believe they are dying due to their lack of root flare. Trees should not look like power poles, but instead need to show off their root flare for all to see.
Root flare is the top of the roots at the point where the trunk ends and the roots begin.
Visualize trees growing in a native setting. Most of them have their root flare exposed. It is the preferred way to grow, and most trees in the wild know it.
Unfortunately, many homeowners aren't aware of it and therefore often plant their trees too deep, leading to later problems.
If the root flare is buried, it will become stressed and can even rot. It won't happen overnight. It usually occurs after you have invested 10-15 years worth of care into that tree.
When it does happen it will begin to lose its vigor, appear stressed, and even begin to deteriorate or go backwards. There is no cure for this.
When a tree is planted at the proper depth, the roots grow just under the surface and even break the surface slightly getting the necessary oxygen and nutrients it needs. When the tree is planted too deep, the roots have to try and grow up towards the surface leading to tree girdling. Tree girdling interferes with tree growth, and we end up with more above ground growth than the girdled roots can support.
Planting trees at the right depth is the key and then also following that up with proper mulching techniques is the key. When you mulch a tree you should leave 4-6 inches between the tree flare and the mulch, preventing any future root rot. Never be afraid to show the tree's root flare!
The Extension Office has information on how to properly plant a tree that can be picked up or downloaded online. Also if you are considering planting a windbreak or conservation tree planting next spring, the Kansas Forest Service is now accepting orders for just such trees. For information on these bulk trees, google the Kansas Forest Service and click on their conservation tree planting tab.