Hidden world: excavating extensive rot in a mango tree
A Hidden World Inside a Mango Tree: Rot, Worms, and Recovery
Tree care is often full of surprises, but this mango tree truly stopped me in my tracks. What began as a fairly straightforward case of rot in the crotch of a large mango tree turned into one of the most unusual discoveries I’ve ever seen: a massive colony of worms living inside the trunk itself.
This case was a reminder of how trees are not just living organisms — they’re also hosts to entire ecosystems. Sometimes those ecosystems help, and sometimes they accelerate decline. Here’s the step-by-step process of how I addressed the rot, what I found, and how the tree is being given a second chance.
Step 1: Clearing the Cavity
The first step was to remove invasive and adventitious plants that had rooted in the decayed area. These small plants may look harmless, but they trap moisture, debris, and pathogens that worsen decay. By removing them, I was able to expose the true extent of the cavity and prepare for proper treatment.
Adventitious plants growing directly from the cavity.
Step 2: Excavating the Rot
With the plants gone, I carefully began removing the dirt and decayed wood inside the cavity. This is where things took an unexpected turn.
As I dug deeper, I uncovered hundreds of worms living inside the heartwood. While earthworms are wonderful for soil health, they don’t belong inside living trees. Their presence here was only possible because rot had already broken down the wood fibers, turning the tree’s interior into a damp, soil-like habitat.
The sheer quantity of worms was astonishing — I’ve never seen anything like it in my career.
One of the first worm clusters revealed during excavation.
Worms living between softened fibers of the rotted wood.
This cavity was literally crawling with worms once the soil was pulled out.
The interior of the trunk was behaving more like a compost pile than heartwood.
Closer look at worms emerging from the decomposed sections.
Step 3: Wire Brushing & Fungicide
Once the worms and loose rot were removed, I needed to chase every last bit of compromised wood. Using a wire brush on a power drill, I carefully followed the veins of decay, cleaning until I hit solid wood. This process is crucial because leaving behind soft, infected tissue would only allow the rot to continue spreading.
Wire brushing to remove softened fibers and expose clean wood.
After the cavity was fully cleaned, I treated it with a high-concentration copper fungicide. This strong application kills fungal pathogens and helps sterilize the wound so it can begin to stabilize.
Copper fungicide soaking into freshly exposed wood.
Step 4: Sealing the Wound
With the fungicide applied, I sealed the cavity with a mineral-infused tree sealant. This step serves multiple purposes:
Protects the wound from further fungal infection.
Keeps out moisture and soil.
Creates a barrier against pests that might otherwise colonize the cavity.
The result is a smooth, protected surface that gives the tree a fighting chance to compartmentalize the damage.
A thick protective seal applied across the cavity.
Step 5: Structural Work Still Ahead
The large nub left in the tree crotch is too big for my saws to remove safely. A tree trimming crew with larger equipment will be brought in to make the final cut. Once that work is complete, I’ll return to reseal the exposed wood.
On the backside of the tree, I also uncovered an active fire ant colony. Excavation there had to be paused until the colony is properly addressed.
Lessons from This Case
This mango tree became an example of how complex tree care can be. What looked like a simple rot cavity turned into an entire ecosystem of worms, fungi, and invasive ants thriving inside the trunk.
By systematically removing the rot, sterilizing the wound with fungicide, sealing the cavity, and planning for structural pruning, this tree still has a chance at long-term recovery.
For me, the biggest lesson here was a reminder that trees are not just trees — they are living systems that interact with soil, plants, fungi, and animals. Sometimes that interaction helps, and sometimes it hurts. But with the right care, even a tree that seems overwhelmed by decay can continue to stand strong.
🌿 Have you ever seen anything like this?