A Redditor's mother had a tree fall on her property, and they reached out to the r/arborists community to figure out what happened. 

"Did the mulch ring do this?" wrote the original poster alongside a photo of the fallen tree. "And will it do it again on this other tree? I've been trying to tell my mom they aren't great for trees."

The poster is right that piling mulch high against a tree isn't good for its health. When the root flare isn't exposed at the base of a tree near the ground, roots are likely to grow into the mulch pile in order to find air. 

As a trunk grows and gets thick, these roots can actually strangle the tree. This is called a girdling root, and is a lethal problem for many trees subjected to "mulch volcanoes." 

High mulch also stores excess moisture, which can wear down the bark and provide an opportunity for infection. 

Maintaining good tree health is crucial to an all-natural yard. Mature trees are a cornerstone to supporting local biodiversity, and they reduce heat island effects through shade and transpiration. The deep root systems of trees also prevent erosion and mitigate surface flood conditions. 

Best of all, healthy trees sequester carbon and improve local air quality. One study suggested that the UK enjoys $4.5 billion in benefits from trees annually.    

Reddit community members could not decisively say if mulch volcanoes were the issue the original poster was facing. They did propose a few potential contributing factors. 

"Rocks … compact the soil, get too hot, and become a barrier to the roots growing properly across the soil level for proper gas exchange with the air above the earth," said one commenter. 

"They should live for many, many decades," wrote another community member. "Sadly, when humans get involved mimicking fads they see (started by lazy/greedy landscapers) — tree rings, hosta tutus, and mulch volcanoes — trees are doomed to fail long before their time."

What's the hardest thing about taking care of your yard? Mowing the lawn 🏡 Controlling weeds 🌿 Keeping pests at bay 🐿️ I don't have a yard 🤷 Click your choice to see results and speak your mind.

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