The Term “Volcano Mulching” refers to a practice of piling mulch against the trunk of a tree, thereby creating a “Volcano” shape at the base of the tree. This approach to mulching is extremely harmful to the health of trees.
While mulching can be one of the most beneficial things that you can do to keep your trees healthy, if done improperly, it can lead to disease, infestation and even the death of the tree. Following are tips on how to be sure that your trees are being mulched properly:
** Mulch should be spread out away from the base of the tree to expose the base of the root flare.
** Apply mulch to a depth of approximately four inches. This will settle to two inches after a few rains, which is the desirable level, and is shallow enough for rain to reach the roots.
** Mulch out away from the tree in a 4-5 foot diameter. Ideally, trees should be mulched to the drop line (below the farthest reaching branches).
** Consider mixing hardwood mulch with grass clippings, sawdust, pine needles, compost and shredded leaves to increase porosity. Using a ground cover plant instead of mulch or grass is also a good choice.
** Check mulch levels each year. Trees often do not need to be mulched annually.
** Avoid cypress mulch, since it is highly water absorbent, reducing the amount of water that reaches the tree roots.
** Dyed mulch is less desirable because it is usually made from chemically treated scrap lumber that can leach chemicals into the soil. The dye itself is also often made from synthetic chemicals.
If your tree has been “Volcano” mulched, use gloved hands to remove mulch from the base of the tree, exposing the root flare. Do not use a rake or shovel, as this can damage the delicate roots.
Please enjoy your summer and enjoy working in your yard!