Emerald Ash Borer Treatment Cost in Denver — 2026 Guide
EAB is confirmed and active in Denver, and roughly one in six trees in the metro is an ash — about 1.45 million trees with zero natural immunity. Here is exactly what protecting yours costs in 2026, what treatment involves, and when removal is the smarter spend.
How Much Does EAB Treatment Cost in Denver?
Emerald ash borer trunk-injection treatment in Denver costs $100 to $450 per tree in 2026 — roughly $10–$15 per inch of trunk diameter — and protects the tree for two full years. Very large or multi-stem ash can run $500–$700. Compare that to removing a dead mature ash at $1,500–$2,500+ (often crane work), and treatment is the clear economic winner for any healthy ash you want to keep.
EAB Trunk Injection Prices by Trunk Size
Measure trunk diameter at chest height (DBH). Prices are per treatment cycle; each trunk injection with emamectin benzoate protects for two years.
The Denver Ash Decision, By the Numbers
A medium ash costs roughly $900–$1,500 to protect for an entire decade (5 cycles). Its shade, property value, and cooling are worth multiples of that.
EAB can work inside a tree for 2–3 years before the canopy shows it. By the time thinning is obvious, larvae have been feeding for seasons. Preventive treatment is the only reliable protection.
Once an ash has lost more than half its canopy, recovery odds are poor. Removal ($1,500–$2,500+) plus a replacement planting is the better spend.
EAB-killed ash become brittle fast and shed large limbs. Dead-ash removals cost more each year they stand, because the tree becomes too unsafe to climb.
Treatment Methods Compared
Trunk injection (emamectin benzoate) is the gold standard: the insecticide is sealed inside the tree — nothing in your soil or air, safe around kids and pets — kills larvae already feeding, and lasts two years. Soil drench (imidacloprid) costs less per application but must be repeated every year, is weaker on large trees, and puts product in the ground. Bark and foliar sprays only touch adult beetles and are not reliable protection. Emamectin benzoate products are applied by Colorado Department of Agriculture licensed applicators — this is not a DIY treatment.
Denver EAB Treatment Cost FAQs
How do I know if my tree is an ash?
Ash trees have opposite branching (branches directly across from each other), compound leaves with 5–9 leaflets, and diamond-pattern bark on mature trunks. Text us a photo — we identify ash for Denver homeowners at no charge.
When is the best time to treat for EAB in Denver?
Mid-spring through early summer (May–June), when the tree is actively moving water and pulls the injection through its canopy fastest. Treatments work into summer; fall injections are less efficient.
How often does EAB treatment need to be repeated?
Trunk injections protect for two years, so a protected ash needs treatment every other year for as long as EAB pressure exists in the metro — which experts expect to be 10+ years.
Can I treat my ash tree myself?
Over-the-counter imidacloprid drenches exist for small trees, but the most effective product — emamectin benzoate trunk injection — requires a Colorado-licensed pesticide applicator and professional injection equipment. For any ash over ~10″, professional treatment is the only option that reliably works.
Is EAB treatment worth it compared to removal?
For a healthy ash, almost always. Ten years of protection for a medium ash costs $900–$1,500; removing the same tree dead costs $1,500–$2,500+, plus decades before a replacement tree gives comparable shade. Mature landscape trees add 5–10% to Denver property values.
Related Denver Pricing Guides
Free Ash Assessment — Know Before EAB Decides for You
An ISA member arborist confirms whether your tree is ash, checks for EAB signs, measures DBH, and quotes treatment on the spot. No cost, no obligation.
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