Maintaining a mulched saucer around your trees is a good practice to ensure your tree has optimal fitness. It is easy for landscapers and unknowledgeable homeowners to pile up soil at the base of a tree. Though the intention is to make the yard look more aesthetically pleasing, piles of mulch or soil at the base of a tree trunk can lead to decay.

mulch dangerous to a tree

Yearly edging of dirt rings around trees usually results in a pile-up of soil around the base of the tree. Soil is removed from surrounding grass, pavement, etc. where it has spilled over from new soil being added to prevent the ring from growing. In this act, the soil is pushed into the center of the saucer piling up against the tree. The excess soil from edging ideally should be removed instead of left to pile up.

Piling mulch at the base of the trunk is not good maintenance for optimal tree fitness. There is a name for this bad habit it is called volcano mulching. When the mulch is piled high against the trunk base it holds excessive moisture leading to moisture buildup in the tree bark. Too much moisture leads to the decay of the bark. Bark acts as a protective “skin” for the tree and when it decays this welcomes in the growth of fungi, bacteria, and insects living underneath the bark that lead to internal damage. Bark needs to breathe and make contact with air to function properly and protect the tree. Piles of mulch also attract larger pests like mice and meadow voles that feed on bark and end up killing the tree.

Keeping a two to three-inch deep saucer around a tree is a great practice for the fitness of your trees as long as it is done properly. Grass is beautiful, but it competes with tree roots for oxygen, moisture, and nutrients. Mulch around a tree also protects roots and bark from the damage of grass maintenance tools used weekly to maintain the lawn.

A mulched saucer around a tree should be as wide as the tree’s canopy, but this is not always practical or aesthetically pleasing in a smaller lawn with very large trees. In these cases, even a small ring of shallow mulch can be beneficial, Make sure to keep an eye on mulch buildup even when the saucer is just a few inches to prevent tree decay.

Lineage Tree Care provides expert Seattle area tree services. Give us a call for tree maintenance you can trust.

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