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This thin set of layers under the bark is essential for the tree’s life. It’s not a perfect analogy to think of these thin layers as being like all of our blood vessels and lymphatic tissues which move stuff around our bodies. But if you choke it off, guess what happens.

Strengthening Weakened Trees

Floods and storms can affect trees, promoting instability and weaknesses. But if you decide to guy or otherwise anchor your trees, do it in ways that will not eventually kill the poor thing.

If you think a small tree is unstable, by all means use some guying lines to prop it up until its roots can support it. This means using loose cordage that still allows for some tree movement. It must be loosened before the tree grows into it. Healthy, properly planted trees should be able to support themselves after one growth season, or maybe two for a large transplant.

If you have a larger tree that seems unstable, consult the services of a qualified arborist. This goes for parts of trees too. If it seems like a piece of a tree is overly heavy and leaning, an arborist can often mitigate the issue through judicious pruning and some cabling. There are cabling options that go around limbs and are designed to expand with the tree’s growth, although this should be checked each year or two. Other types of cabling involve bolts that go right through the tree. This would seem drastic if you did not know the science behind how trees grow. A small hole through the important tissues and through the dead heartwood of a tree is less harmful than a constricting wire or cord that will eventually impact all the important tree tissue. It is true that a breach of the bark can allow a pathway for fungus or disease, but healthy trees can usually take care of small holes.

If you put things on your tree for fun, like Christmas lights,swings or hammocks, be sure to take them off every year, or re-position them, or use bolts.

Be kind to your trees. Treat them like the large, growing urban companions that they are. Observe your trees. Don’t let the first telltale signs of a tree in distress be the fact that it is lying on its side over your new car.