How can I tell if my backyard tree is diseased or dead?

Saving a Diseased Tree

As with any disease, avoiding it is preferable to treating it and a healthy tree is inherently more disease-resistant. In order to keep your trees healthy, try the following steps:

  • Avoid putting weed fertilizer on grass anywhere near the tree's roots.
  • If you mulch around the tree, leave a little space around the trunk to let it breathe and avoid rotting the wood.
  • If your tree has exposed roots, hand trimming that area is preferable to using a lawn mower or anything with a sharp blade.
  • Watering trees during droughts is important because tree roots move up toward the top of the ground in search of water, which can weaken the tree's root structure.
  • Proper pruning practices are vital, because a wrong cut can leave the tree susceptible to disease. Different species have different requirements for how to prune, so consult your local nursery or tree specialist for instructions on keeping your tree trimmed and healthy.

If you don't do what you can, it could lead to disastrous results. Some diseases have had such an impact that they've caused the loss of an entire species of trees. Dutch Elm Disease (DED) devastated the American Elm population. DED is a fungus that clogs vascular tissues, which are how trees get water. Elm bark beetles also play a part because they're attracted to diseased trees to complete the breeding stage of their life cycle. When the larvae emerge as adults, they eat the spores of the DED fungus and transmit it to other trees when they move on. Once a tree in a row is infected, it rapidly moves through the connected root systems and kills all the other trees in its path. A lack of water kills the crown, and the tree wilts and dies.

For more information on saving your trees, take a look at some information below.

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