Tree Diseases in Kansas City

 

Tree Diseases in Kansas City: What I’ve Seen, What Still Works, and What You Need to Know

After 35 years in arboriculture, I can tell you: some of the worst damage I’ve seen to Kansas City’s trees hasn’t come from storms, construction, or even age. It’s come from diseases—the kind that get inside a tree and slowly take it apart, limb by limb, from the inside out.

Most of the time, homeowners don’t catch it early — and I don’t blame them. These problems usually start with tiny changes: a branch that leafs out late, bark that cracks just slightly, or leaves that drop a few weeks early. These are the things that almost nobody sees… unless they’ve spent decades learning what to look for. That’s why having an ISA Certified Arborist inspect your trees every year isn’t just a good idea — it’s essential.

When I’m out walking a property, I’m not just looking at what’s dead. I’m looking at what’s about to be. Because by the time most folks notice a problem, the damage is already deep inside the tree.

The Hidden Pattern of Tree Decline

Tree disease usually doesn’t hit like a storm. It creeps in. One year the canopy looks a little thinner. The next

year you’ve got tip dieback. Then suddenly, a major limb drops in the middle of summer — or worse, the whole tree is lost.

The most common call I get is: “It just started looking weird.” That’s usually the tip of the iceberg. And in Kansas City, with our range of native hardwoods, tough clay soils, and wildly fluctuating seasons, tree disease finds plenty of opportunity to take hold.

1. Dutch Elm Disease: The Classic Killer

Decades ago, this disease wiped out thousands of elms across the Midwest, and it’s still out there. I’ve seen it take out stately boulevard elms that were planted to replace the original loss from the first wave back in the 70s.

Dutch elm disease is spread by elm bark beetles and root grafts, making it nearly impossible to stop once it’s in an area. It clogs the tree’s vascular system, leading to flagging branches (where sections of the canopy suddenly wilt and brown), followed by quick decline.

When I start seeing early yellowing, wilting from the top down, and brown streaks under the bark, I know we’re looking at something serious. Without early detection, it’s usually a matter of weeks before that tree is gone.

2. Oak Wilt Disease: Fast, Fatal, and Underestimated

In red oaks, oak wilt is one of the most aggressive killers I’ve seen. It spreads underground through connected roots, and above ground by beetles carrying fungal spores from one fresh wound to another.

This is why I constantly remind clients: never prune your oaks in spring or early summer unless it’s absolutely necessary. That’s prime infection season. Every open cut is an invitation.

Oak wilt usually shows up as leaves browning from the edges inward, curling, and dropping prematurely. Once it reaches the main trunk, death can come fast. A majestic tree can go from vibrant to bare in a single season.

3. White Rot Disease: The Silent Decomposer on Ash

White rot isn’t flashy — no big leaf symptoms, no dramatic dieback at first. But it’s devastating over time. Caused by wood-decaying fungi, white rot breaks down the lignin in hardwood trees, leaving the structure soft and spongy.

And yes — ash trees are especially vulnerable. I’ve seen older ash specimens decline from white rot that began unnoticed at the base or deep within the trunk. You might not even know it’s there until a storm hits and a major limb fails — or the whole trunk splits open.

I see this most often in ash and maple trees around Kansas City, especially those that have been overwatered, mulched too high, or planted too deeply. Once decay sets into the root flare or lower trunk, it’s nearly impossible to reverse.

4. Emerald Ash Borer: Destruction by Design

This metallic green beetle isn’t technically a disease, but it causes disease-like decline that ends the same way — death. And like white rot, it specifically targets ash trees.

Emerald ash borer (EAB) lays its eggs on the bark. The larvae burrow in and feed just under the surface, creating S-shaped galleries that choke off the tree’s vascular flow. Trees thin from the top down, bark splits, and within 2–4 years, the tree is often beyond saving.

I’ve treated early-stage infestations with injections — and when done early, they can save a tree. But once 30% or more of the canopy is gone, removal is usually the smarter long-term decision.

That’s why I often advise clients: if you’ve got an ash tree in Kansas City, it needs to be ins
pected every single year — because between white rot and EAB, it’s being attacked from the inside and out.

Why You Need an ISA Certified Arborist

There’s no app, no tool, no YouTube video that can match what you get from walking a property with someone who’s done this work for decades. I don’t just spot the obvious — I catch the early signs that tell me what’s coming next.

Whether it’s a subtle discoloration in an oak leaf or the hollow thud of a decaying ash trunk, I know what to look for and what to do. And more importantly, I know when not to wait.

An annual inspection gives us a chance to catch issues before they become removals. That means fewer surprises, lower costs, and healthier trees year after year.

The Bottom Line: Act Before the Problem Grows

In my 35 years working with Kansas City’s trees, I’ve seen how easily diseases spread when ignored — and how often they could’ve been stopped if someone had just acted a little sooner.

So if you’re seeing early leaf drop, bark splitting, canopy thinning, or anything that feels “off,” call a pro — preferably one with an ISA badge and boots that have spent years in the field.

Because when it comes to tree health, the earlier we act, the more we save.


—
Paul Weaver
ISA Certified Arborist