Things I Can’t Explain: Mulch Volcanoes

Volcanoes are popping up like fire ant mounds all over this North Texas commercial property. Beware: They serve almost no purpose.

Back when my Facebook page operated normally (posts were kept in chronological order instead of Facebook’s opinion of what was most relevant), I asked my crowd if anyone had any idea why the concept of “mulch volcanoes” might ever have gotten started.

One landscape contractor spoke up. He said it was because some in his industry got tired of having to haul extra soil away from planting sites, so they just pulled it up around new trees’ trunks and concealed it with fresh bark.

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The more I thought about that, the more sense it made. It’s a labor saver, and it keeps grass from growing right up around the trunk.

But this is bad business! It’s really not good for the tree. Let me tell you why.

When you look at a pile of soil and mulch close up you can see how really silly it all looks around a tree’s trunk.

It makes it hard to get water down to the tree’s roots. The soil sheds water off the sides. How much better it would have been to have used that soil to create a shallow doughnut-shaped basin around the tree’s trunk. That would serve as a reservoir every time that you watered the new tree by hand its first couple of years. At that time the berm could easily have been burst open and leveled with a hoe.

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The pile of soil and even bark mulch or compost compresses to cover the tree’s root flare. The more compacted it is, the more harm it can cause to the tree.

These piles of soil and mulch have been broadening for years. It’s still as bad an idea as ever.

My third reason is strictly a matter of personal opinion, but I don’t think of the tree’s trunk as being its most handsome asset. I don’t want to draw attention to it where it enters the soil line any more than I want to draw attention to the foundation of my house or my work shoes that I wear. Some things are just better left unnoticed.

The takeaway from it all? Do away with mulch volcanoes and let the tree exist as it would in nature.

Posted by Neil Sperry
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