Emerald Ash Borer in Dane County
Emerald ash borer has been confirmed throughout Dane County, putting thousands of ash trees at risk. Without treatment, every infested ash tree will die within 3 to 5 years. Our ISA Certified Arborists provide expert EAB assessment, trunk injection treatment, and safe removal of infested trees.
Financing available — low monthly payments
Signs of Emerald Ash Borer Infestation
Early detection is critical. EAB larvae feed beneath the bark, disrupting the tree's ability to transport water and nutrients. By the time visible symptoms appear, infestation may already be 1 to 2 years old. Know what to look for on your Dane County ash trees:
D-Shaped Exit Holes
Adult EAB beetles emerge through distinctive D-shaped holes approximately 1/8 inch wide. These are usually found on the trunk and major branches. Unlike round woodpecker holes, the flat side of the D distinguishes EAB exit holes from other boring insects.
Canopy Dieback From Top
EAB larvae feed in the cambium layer, disrupting nutrient flow. Dieback starts in the upper canopy and progresses downward over 2 to 3 years. By the time one-third of the canopy is dead, the infestation is advanced. Early detection — when only the uppermost branches show thinning — gives treatment the best chance of success.
Increased Woodpecker Activity
Woodpeckers feed heavily on EAB larvae beneath the bark, creating noticeable bark flaking patterns. If you suddenly see heavy woodpecker activity on an ash tree — especially in winter when they're actively foraging — it's a strong indicator of EAB presence beneath the bark.
S-Shaped Larval Galleries
Peeling back bark on an infested tree reveals serpentine (S-shaped) feeding galleries carved by EAB larvae as they consume the cambium. These galleries sever the tree's vascular tissue, eventually girdling entire sections and killing them. Gallery density increases with infestation severity.
Epicormic Sprouting
Stressed ash trees produce new shoots (epicormic sprouts) directly from the trunk and major branches as a survival response to canopy loss. This abnormal growth pattern indicates the tree is losing its upper canopy and redirecting energy to emergency foliage production lower on the trunk.
Vertical Bark Splitting
As larvae feed and grow beneath the bark, the outer bark often splits vertically, exposing light-colored sapwood and callus tissue. Bark splitting is especially visible on smooth-barked younger ash trees and on the trunk of green ash species common in Dane County landscapes.
EAB Treatment Options for Dane County
Not every ash tree should be treated, and not every ash tree should be removed. Our arborists evaluate each tree individually based on canopy condition, structural integrity, location value, and cost-effectiveness to recommend the right approach.
Trunk Injection — Emamectin Benzoate
The gold standard for EAB treatment. Emamectin benzoate (trade name TREE-age) is injected directly into the trunk at the root flare, where it's distributed through the vascular system to the canopy. One treatment provides 2 to 3 years of protection. The insecticide kills EAB larvae feeding in the cambium and adults feeding on leaves. Treatment is most effective when canopy loss is below 30%.
Treatment Timing
In Dane County, the optimal treatment window is mid-April through mid-June, during active transpiration. Trees treated during peak sap flow distribute the insecticide most efficiently. Fall treatments (September to October) provide a secondary window. We schedule treatments based on current conditions and species-specific timing for maximum effectiveness.
Which Trees Are Worth Treating
Generally, ash trees worth treating are structurally sound with less than 30% canopy loss, in desirable locations (providing shade, screening, or aesthetic value), and in good overall health apart from EAB. Trees with significant pre-existing decay, poor structure, or advanced infestation are better candidates for removal and replacement.
Treatment vs. Removal: Cost Comparison
Understanding the long-term economics helps you make the best decision for each ash tree on your property.
Treatment (Preserve the Tree)
- Cost: $8-$15 per diameter inch every 2-3 years
- 20-inch ash: ~$200 per treatment cycle
- 10-year cost: approximately $800 to $1,000
- Tree continues providing shade, property value, aesthetics
- Best for: healthy trees with <30% canopy loss
- Requires ongoing commitment to retreatment
Removal (Replace the Tree)
- Removal cost: $1,500 to $3,000+ depending on size/access
- Stump grinding: additional $200 to $500
- Replacement tree planting: $300 to $800
- One-time cost, but you lose mature shade for 15-20 years
- Best for: heavily infested or structurally compromised trees
- EAB-killed ash becomes brittle — delay makes removal more dangerous and expensive
Important: delaying removal of EAB-killed ash trees increases cost and danger. Dead ash wood becomes extremely brittle within 2 to 3 years, making it unsafe to climb and more likely to fail unpredictably. If removal is the right choice, don't wait.
Our EAB Management Approach
We take a systematic, property-wide approach to EAB management rather than treating trees one at a time.
Complete Ash Inventory
We identify and measure every ash tree on your property, noting species (green, white, or black ash), diameter, canopy condition, structural integrity, and current infestation status.
Individual Assessment
Each tree gets a treat-or-remove recommendation based on its health, structural value, location importance, and cost-effectiveness. We present options so you can make informed decisions.
Treatment & Removal
We execute the plan — trunk injections for trees worth saving, safe removal for those that aren't. Removal is done before the wood becomes dangerously brittle. Stump grinding included.
Ongoing Monitoring
Treated trees need retreatment every 2 to 3 years. We schedule follow-ups, monitor treatment effectiveness, and adjust the plan as conditions change. Replacement tree recommendations are included.
Dane County EAB Experts
Our Madison office serves all of Dane County for emerald ash borer treatment and removal. We've treated hundreds of ash trees across Madison, Middleton, Fitchburg, Sun Prairie, Verona, and surrounding communities.
Call our Madison office at (608) 716-4167 to schedule a free EAB assessment for your property.
Emerald Ash Borer FAQs
Common questions about EAB treatment and removal in Dane County.
Is emerald ash borer confirmed in Dane County?
Yes. Emerald ash borer (Agrilus planipennis) has been confirmed throughout Dane County since its initial detection in the early 2010s. Every untreated ash tree in the county is at risk. EAB has a nearly 100% kill rate on untreated ash trees within 3 to 5 years of infestation.
What are the signs of emerald ash borer infestation?
Look for D-shaped exit holes (about 1/8 inch wide) in the bark, S-shaped larval galleries under the bark, increased woodpecker activity (they feed on EAB larvae), canopy thinning starting from the top, epicormic sprouting (new shoots on the trunk), and vertical bark splitting. By the time you see significant canopy dieback, the tree may be too far gone for treatment.
How much does EAB treatment cost vs removal?
Treatment with emamectin benzoate trunk injection typically costs $8 to $15 per inch of trunk diameter (measured at 4.5 feet height) and lasts 2 to 3 years per application. For a 20-inch diameter ash, that's roughly $160 to $300 every two years. Removal of the same tree costs $1,500 to $3,000+ depending on location. Over a 10-year period, treatment is usually cheaper than removal — and you keep the tree.
When is the best time to treat ash trees for EAB?
The optimal treatment window is mid-April through mid-June in Dane County, when trees are actively transpiring and can distribute the insecticide throughout the vascular system. Fall treatments (September-October) can also be effective. Avoid treating during extreme drought when transpiration is reduced.
When should I remove an ash tree instead of treating it?
Remove rather than treat when: canopy loss exceeds 50%, extensive bark splitting exposes sapwood, the tree has significant structural defects unrelated to EAB, the tree is in a location where failure would hit a structure or high-traffic area, or the tree's size and condition make ongoing treatment costs exceed its value. Our arborists help you make this decision based on each tree's specific circumstances.
Does the City of Madison have an ash tree removal program?
The City of Madison's Urban Forestry department manages ash trees on public terraces (between the sidewalk and street). They have been systematically treating high-value public ash trees and removing infested ones. Private property ash trees are the homeowner's responsibility. Tree Wise Men handles both treatment and removal for residential and commercial properties throughout Dane County.
Don't Let EAB Kill Your Ash Trees
Schedule a free emerald ash borer assessment for your Dane County property. Our ISA Certified Arborists will evaluate every ash tree and recommend the most cost-effective management plan.