đź’€ The Volcano and the Flush Cut: 3 Deadly Mistakes Homeowners Make When Caring for Trees
Tree care seems simple: water, trim, and mulch. Unfortunately, many popular yard practices—often started with the best intentions—are actually slowly damaging your trees, opening them up to pests, disease, and structural failure.
At Trees and Co. Arborists, we see the results of these common errors every day. These three deadly mistakes can drastically shorten your tree's lifespan and should be avoided at all costs.
1. The Volcano: Piling Mulch Against the Trunk
Walk through any neighbourhood and you'll see it: a neat, conical pile of mulch mounded high against the base of a tree. This is often called Volcano Mulching, and it is one of the most destructive habits for your tree’s health.
The Mistake:
Piling mulch directly against the root flare and trunk keeps the bark constantly wet.
The Damage:
Trunk Rot: Constant moisture breaks down the bark, inviting fungal decay and pathogens that can girdle (choke) the tree.
Root Suffocation: The dense, mounded mulch cuts off oxygen and encourages the growth of roots into the mulch pile rather than into the native soil, leading to unhealthy, weak root systems.
Pest Invitation: Warm, wet mulch is a haven for pests, including rodents that chew on the soft bark under the protection of the mulch.
The Arborist’s Fix: The Mulch Donut
Mulch is fantastic for regulating soil temperature and retaining moisture, but it must be applied correctly:
Find the Root Flare: Locate the base of the trunk where the roots begin to flare out (it should look like a bell, not a telephone pole).
Apply 2-4 Inches Deep: Spread a layer of mulch 2–4 inches deep in a circle extending out to the drip line.
Create a Gap: Keep the mulch 2–3 inches away from the actual trunk at all times. This creates the "donut" shape, keeping the base dry while protecting the soil.
2. The Disaster-in-Waiting: Tree Topping
Tree topping is the practice of cutting main branches back to stubs or uniform height to drastically reduce the tree’s size. While it seems like a quick solution for an overgrown tree, it is an absolute disaster waiting to happen.
The Mistake:
Removing the majority of the leaf-bearing crown.
The Damage:
Starvation: By removing the leaves, you remove the tree's food factory, putting it under extreme stress.
Weak Growth: The tree reacts by sending out dozens of fast-growing, weak vertical shoots from the cut stubs. These shoots are poorly attached to the main branch.
Increased Storm Risk: This weak, rapid growth structure is extremely brittle. Years later, these poorly attached branches are the first things to snap off in high winds, leading directly back to the catastrophic storm damage we discussed in our last post.
Decay: The large wounds left by topping rarely heal properly, allowing moisture and decay fungi to enter the main structure of the tree.
The Arborist’s Fix: Reduction Pruning
A Certified Arborist will never top a tree. We use Reduction Pruning to selectively cut a branch back to a strong lateral side branch that can assume the growth dominance. This preserves the tree's natural structure, controls size, and maintains a strong, healthy canopy.
3. The Unhealable Wound: Improper Pruning Cuts
Pruning is surgery for a tree, and just like surgery, the cut must be precise to heal correctly. Homeowners often make two critical mistakes that prevent the tree from closing the wound properly.
The Mistakes:
The Flush Cut: Cutting a branch too close to the main trunk, removing the Branch Collar.
The Stub Cut: Leaving a section of the branch (a "stub") sticking out from the trunk.
The Damage:
Halted Healing (Flush Cut): The branch collar is the swollen ring of tissue where a branch connects to the trunk. It contains the specialized cells needed to create callus wood and seal the wound. Cutting through it prevents the tree from compartmentalizing the injury, leading to extensive decay in the trunk.
Stub Rot (Stub Cut): The stub dies back to the trunk and starts to rot before the tree can close off the wound. This rotting wood funnels decay and moisture directly into the main trunk.
The Arborist’s Fix: Cutting to the Collar
The proper technique is to make the cut just outside the branch collar and perpendicular to the bark ridge. This preserves the essential healing tissue, allowing the tree to quickly and naturally compartmentalise the wound.
Don't Let Good Intentions Lead to Bad Results.
Your trees are built to last, but they rely on proper, knowledgeable care. Incorrect mulching, topping, or pruning may seem fine today, but the damage will compound for years, leading to expensive and dangerous outcomes tomorrow.
Ready to ensure your trees are set up for a long, healthy life? Contact Trees and Co. Arborists today to schedule a structural pruning or property consultation. We bring professional knowledge—and the right tools—to the job.