Reality: Mulch is too thick when a tree root starts growing into it.

The right amount of mulch is very beneficial for trees. Mulch helps a tree by keeping the soil moist, protecting soil from getting too hot, and as the mulch decomposes over time it will add organic matter, improving the soil quality.

However too much of a good thing is possible when mulching trees, and care must be taken to keep the much free from the trunk.

Too Much Mulch Can Cause Root Girdling

Expert Tree Care and Root Girdling Treatment in Sarasota - Ensuring Healthy Trees and Strong Root Systems

When mulch is too thick, the tree may begin to grow roots up out of the soil and into the mulch. This can cause a condition called root girdling. When toot girdling occurs, the roots will grow laterally at or near the service of the soil and constrict around the trunk. As the tree trunk and the roots, both will get thicker as time goes on, the lateral roots will eventually cut into the trunk of the tree and begin to “strangle” the trunk.

Avoiding this root girdling is easy, however. Make sure mulch is at least 6 inches back from the trunk, and be sure when you apply mulch that the layer of mulch is not deeper than 4 inches or so.

Keep Mulch Back From The Trunk To Avoid Pest, Fungus & Disease Issues

Keeping the mulch layer from touching the trunk will have several important benefits including, reducing chances of injury and infection by pathogens, or pests as the mulch will stay moist and hide insects that can exploit any damage to the tree bark.

Fungal and bacterial diseases can thrive in wet environments, and keeping mulch at least 6 inches away from the trunk will ensure the base of the trunk stays healthy and dry while allowing a clear patch of ground for rainwater to freely access the soil.

Excessive Mulch Can Hide Problems With The Trunk

Excessive mulch can also hide decay and dead spots on the lower trunk of the tree and major roots of all trees. Decay in this portion of the tree can cause the tree a host of serious problems and may eventually lead the tree to become unstable.

Excessive Mulch Can Interfere With Water Percolation And Soil Aeration

Additionally, too much mulch over the root ball can intercept water by absorbing rainwater from moderate rainstorms that could have reached the roots. This can become an issue during dryer times of the year and actually prevent water lighter rains from draining through to the root system.

Additionally, a thick damp layer of rotting mulch can actually make it more difficult for gasses to be exchanged with the soil – soil aeration is key for plant health.

So in summary, while mulch provides a wealth of important benefits to your trees, care must be taken to apply mulch correctly or you may cause more problems than you help. Make sure mulch is at least 6 inches away from the trunk, and be sure the mulch layer is not thicker than 4 inches or so.

If you are looking for professional tree care contact the Certified Arborists at GreenEdge today for your free estimate.

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