What is the Root Flare, and Why Does It Matter?

The root flare, also known as the root collar, is the area at the base of a tree where the trunk expands and transitions into the root system. In healthy trees, this part should be visible above ground. When buried too deep, a tree’s root system can struggle to access oxygen, leading to poor health, disease susceptibility, and even premature death.

The Dangers of Deep Planting in Desert Trees

Phoenix's extreme climate puts trees under enough stress as it is - burying them too deep only adds to their struggle. Desert-adapted trees like mesquites, palo verdes, and ironwoods have evolved to thrive in arid conditions. When their root flares are buried beneath excess soil or mulch, they become vulnerable to:

• Root rot: Poor drainage
• Root rot: Poor drainage and excessive moisture around the trunk encourage fungal growth and decay.
• Girdling roots: Roots that grow in a circular pattern due to deep planting can strangle the tree over time.
• Weak structure: A buried root flare often leads to instability, increasing the risk of tree failure during monsoon storms.

Signs Your Tree is Buried Too Deep

If you can’t see the root flare of your tree, it may be struggling. Here are some warning signs to look out for:

• A trunk that looks like a telephone pole, disappearing straight into the ground with no flare.
• Bark decay or fungal growth at the base of the tree.
• Slow growth, yellowing leaves, or dieback in the canopy.
• Trees that seem unstable or lean easily in high winds.

How to Fix a Buried Root Flare

If your tree has been planted too deep, don’t panic—there are ways to correct the problem. A professional tree service can carefully remove excess soil and expose the root flare without causing damage. Root collar excavations using air tools or pressurized liquids can gently clear soil and mulch while preserving root health.

Proper Planting and Mulching Techniques

To ensure the long-term health of your trees, follow these best practices:

• Plant at the right depth: Make sure the root flare is slightly above ground level when planting a new tree.
• Avoid volcano mulching: Mulch should be spread evenly around the tree but kept several inches away from the trunk.
• Regular inspections: Check your trees periodically to make sure the root flare remains exposed and clear of debris.