How to Properly Mulch Around a Tree _ This Old House
**The Silent Killer: Understanding the Dangers of Mulch Volcanoes and Proper Tree Care**
Trees are some of the most valuable elements in our landscapes, providing beauty, shade, and life-sustaining benefits. However, improper tree care practices can lead to severe damage or even death for these majestic plants. One such issue is the "mulch volcano," a common landscaping practice that has detrimental effects on trees.
In this article, we will explore the dangers of mulch volcanoes, the importance of proper root flare exposure, and effective tree care techniques based on a detailed transcription from a video.
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### The Problem with Mulch Volcanoes
The video begins by highlighting the issue of "mulch volcanoes," a term used to describe excessive piles of mulch around the base of trees. Landscape professionals often pile mulch year after year, creating a volcano-like structure around the tree trunk. While mulch is beneficial in many ways, this practice can be devastating for trees.
The speaker explains that mulch volcanoes suffocate the root mass. Tree roots require oxygen to survive, and by covering them with excessive mulch, landscapers are essentially suffocating the roots. This lack of oxygen leads to bark falling off, which is a clear sign of stress and potential death for the tree. The speaker emphasizes that this tree is "a goner" unless drastic measures are taken.
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### Excavation Reveals Hidden Problems
To demonstrate the extent of the damage, the speaker decides to excavate the affected tree. As they remove the mulch, several issues become apparent:
1. **Drip Irrigation Placement**: The video shows that the drip irrigation system is installed directly on top of the root ball. This placement can further exacerbate the problem by directing water away from the roots and into the mulch layer, which can trap moisture and lead to root rot.
2. **Secondary Root Systems**: The excavation reveals an extensive network of secondary roots growing upward into the mulch. These roots are trying to escape the suffocating environment below but are instead exposed to harsh conditions such as sunburn and frost damage. Over time, these roots can circle around the trunk, leading to a condition known as "girdling," which can strangle the tree and lead to its death.
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### Correcting the Issues
The speaker then demonstrates how to correct these problems:
1. **Removing Mulch**: The first step is to remove all the mulch from around the base of the tree. This allows the roots to breathe freely and prevents further damage to the bark.
2. **Exposing Root Flares**: After removing the mulch, the root flare (the point where the trunk meets the roots) becomes visible. The speaker emphasizes that this is a critical step because it ensures proper air circulation and allows the tree to function as nature intended.
3. **Trimming Secondary Roots**: Any secondary roots growing upward are trimmed to prevent future girdling. This process may seem drastic, but it is necessary for the long-term health of the tree.
4. **Using Air Tools for Soil Removal**: The speaker uses an air compressor to blast soil off the tree base. This method is effective because it removes debris without damaging the roots or the trunk.
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### Replanting and Proper Mulching
Once the root system has been exposed and cleaned, the next step is to replant the tree correctly:
1. **Adding Topsoil**: A thin layer of topsoil is added to fill in any voids around the base of the tree. It’s important not to cover the primary root flare during this process.
2. **Mulching Correctly**: The final step is mulching, but this time it's done properly. Instead of creating a "volcano," the speaker spreads the mulch evenly and keeps it shallow (no more than two inches deep). This approach ensures that the root flare remains exposed while providing benefits such as weed control, moisture retention, and protection from extreme temperatures.
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### Conclusion
The video serves as a stark reminder of the importance of proper tree care. Mulch volcanoes may seem harmless at first glance, but they can lead to severe damage or even death for trees. By exposing root flares, avoiding excessive mulching, and ensuring proper irrigation placement, we can help our trees thrive.
In summary, always remember:
- Avoid piling mulch against the trunk.
- Keep root flares exposed to ensure healthy root development.
- Monitor for secondary roots that may indicate stress or damage.
- Use drip irrigation systems wisely, avoiding direct contact with the root ball.
By following these steps, we can protect our trees and enjoy their beauty and benefits for years to come.