COLORADO EMERALD ASH BORER ASSESSMENT
Ash Borer Assessment
& Action Plan.
Have an ash tree you’re worried about? We help Colorado property owners recognize warning signs of emerald ash borer, understand which trees warrant expert attention, and plan practical next steps before more canopy is lost.
Ken Caryl • Littleton • Highlands Ranch • Parker • Jefferson & Douglas Counties
Before you remove an ash tree—or invest in treatment—know what you’re seeing.
Emerald ash borer (EAB), Agrilus planipennis, is an invasive metallic-green beetle. Its larvae feed beneath the bark of true ash trees, disrupting water and nutrient transport. Damage may go unnoticed for years while the crown still looks reasonably healthy.
Not every declining ash is infested with EAB. Drought, other borers, root issues and construction stress can look similar. An informed assessment starts with tree identification, accessible symptoms, site conditions and the extent of decline.
Stone Elk Land Services focuses on field-based observations, forestry work planning, tree removal and practical property guidance. When a formal diagnosis, certified tree-risk report or pesticide application is needed, we can recommend the appropriate qualified specialist.
Emerald ash borer has been confirmed near your property.
Colorado State Forest Service and CSU Extension identify Ken Caryl in Jefferson County and Parker in Douglas County among 2026 emerald ash borer confirmations. Nearby planted ash trees deserve closer attention, even when obvious symptoms haven’t appeared.
The story is closer to home than many realize.
CBS Colorado reported on the first confirmed emerald ash borer detection in Douglas County and what it means for homeowners along the Front Range. Watch the original news report directly from CBS Colorado’s official YouTube channel.
CBS COLORADO • PARKER / DOUGLAS COUNTY
Video: Watch the report on CBS Colorado’s YouTube channel ↗
Independent news footage. Stone Elk Land Services is not the reporting organization or a featured interviewee.
Is it actually an ash tree?
Emerald ash borer targets true ash (Fraxinus) species. These three clues can help homeowners start the identification process.
Twigs and buds often emerge in pairs across from one another, rather than alternating along the branch.
Most commonly planted ash species have compound leaves, often with five to nine leaflets along a central stem.
Older ash trees may develop distinctive diamond-shaped bark patterns. Young trees may have smoother bark.
Important: Mountain ash (Sorbus) is not a true ash and is not a typical EAB host. The name alone isn’t enough to identify risk.
Six clues that tell us where to look.
Symptoms can have more than one cause. A closer look at the full tree and sometimes under the bark is needed before attributing damage to EAB.
Thinning Upper Canopy
Less foliage, dead tips and declining branches near the top can be signs of damage developing beneath the bark.
New Shoots Low on the Tree
Clusters of fresh sprouts from the lower trunk or major branches may appear as the tree experiences stress.
Tiny D-Shaped Exit Holes
Adult insects can leave roughly 1/8-inch D-shaped holes as they emerge. They may be hard to locate, especially high in the crown.
Vertical Bark Splits
Splitting or cracking can develop as feeding galleries expand beneath the bark. Many other problems can also cause splits.
S-Shaped Galleries
Serpentine tunnels in the inner bark are an important clue when a qualified inspection can safely access them.
Woodpecker Flecking
Concentrated pecking and patches of lighter exposed bark may indicate larvae, but do not confirm the exact insect.
What happens beneath the bark matters most.
Emerald ash borer larvae interrupt the tissues that move water and nutrients, sometimes long before the canopy reveals the extent of the problem.
The whole tree, not a single symptom.
Determine whether the tree is likely a susceptible true ash variety.
Review visible exit holes, bark conditions, woodpecker activity and any available galleries.
Consider overall health, extent of dieback, potential targets, access and surrounding trees.
Discuss monitoring, a licensed applicator’s assessment, removal needs or further diagnosis.
Protect, remove, or replace?
The right response depends on tree value, structural condition, the extent of decline, treatment access and whether EAB is confirmed nearby.
Consider preservation and professional treatment.
A healthy, structurally sound ash tree may be a candidate for insecticide protection. A Colorado-licensed pesticide applicator should evaluate whether, when and how to treat; most options require repeat applications.
Chemical protection requires an appropriately licensed applicator.
Evaluate safe removal and wood handling.
Where a tree is severely declining, at risk of failure, or not a suitable preservation candidate, removal may be the practical next step. The plan should address timing, access, public safety and wood handling.
Structural hazards require a qualified tree-risk professional.
Plan replacement and species diversity.
Replacing lost ash with site-appropriate alternatives can restore shade and reduce future reliance on one species. A staggered replacement plan may be especially useful for HOAs and larger properties.
EAB management is a multi-year decision, not a one-time cure.
Timing matters for treatment and removal.
EAB adults are generally active from late spring through summer in Colorado. Local conditions, tree condition and the product label determine a precise treatment or wood-handling schedule.
Colorado State Forest Service advises special precautions for transporting infested ash wood; consult its current guidance and local requirements.
Clear answers begin with a focused review.
A practical path from your first concerns to informed forestry decisions.
Share
Tell us your location, suspected ash count, photos and what symptoms you noticed.
Inspect
Review accessible trees and visible signs, with tree condition and site context.
Prioritize
Separate immediate hazards and suspect trees from monitoring and treatment discussions.
Plan
Agree on practical next steps, a work scope, and referrals when specialist services are required.
A useful plan—not a sales pitch.
Assessment outputs depend on the agreed scope. We can document findings and discuss practical follow-on forestry services.
Notes on likely true ash trees and areas of concern.
A review of accessible bark and crown indicators without overstating certainty.
Monitoring, removal, or referral for professional treatment/diagnosis.
Discussion of safe timing, handling and disposal for suspect material.
An agreed scope and estimate for Stone Elk field work, when requested.
Photos and mapping for multiple trees, HOAs or larger properties.
Manage the full canopy.
Not just one ash tree.
For neighborhoods, HOA landscapes and larger private properties, optional photo documentation, marked priorities and mapped work areas can help decision-makers budget for tree preservation, removal and replacement over time.
Important: aerial mapping and LiDAR can describe canopy structure and site conditions, but cannot independently confirm an EAB infestation or establish a formal tree-risk rating.
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Documentation options are subject to site conditions, access and the agreed estimate.
Local tree health guidance when it matters.
Stone Elk Land Services supports property owners, HOAs and land managers concerned about emerald ash borer and ash tree decline in and around the Denver foothills and neighboring communities.
Outside these communities? Send your approximate location and property details to confirm availability.
Emerald ash borer: what homeowners need to know.
Is emerald ash borer confirmed in Ken Caryl and Douglas County?
Yes. Colorado State Forest Service and CSU Extension reported 2026 confirmations in Ken Caryl (Jefferson County) and Parker (Douglas County), among other Front Range communities. A confirmed community detection does not prove that any particular tree is infested.
Does emerald ash borer attack all ash trees?
It threatens North American true ash trees (Fraxinus), including green, white and commonly planted cultivars. Mountain ash (Sorbus) is not a true ash and is not a typical emerald ash borer host. A correct tree identification is the first step.
Can a tree look healthy while emerald ash borer is inside?
Yes. Larvae can cause substantial damage under the bark before the crown clearly declines. Some signs become obvious only later. Healthy-looking ash trees in confirmed areas still deserve informed management planning.
Can an emerald ash borer-infested tree be saved?
Some trees in relatively good condition can be protected with properly chosen insecticide treatment. Success depends on canopy condition, timing, product and application. Severely declining or structurally compromised trees may not be good preservation candidates. A qualified licensed professional should assess treatment suitability.
Does Stone Elk Land Services provide trunk injections or spraying?
We provide field observations, forestry planning and eligible removal and land-management work. We do not advertise our service as pesticide treatment; when that is appropriate, seek a Colorado-licensed pesticide applicator. We can help plan surrounding forestry and site logistics.
Should I remove my ash tree even if it is not infested?
Not automatically. A healthy, valuable ash tree may justify treatment and monitoring, while removal or gradual replacement may make more sense in other cases. Consider shade value, size, safety, maintenance and long-term costs.
Can I move ash firewood after a tree is removed?
Do not transport untreated infested ash wood to another location. Colorado State Forest Service advises on-site use when appropriate and special chipping, debarking, removal timing and disposal precautions if movement is unavoidable. Confirm current local requirements.
Is an assessment the same as a diagnosis or formal tree-risk assessment?
No. Our assessment is a field-based review of visible evidence and practical forestry options. If insect confirmation, laboratory analysis, a formal tree-risk rating or licensed chemical treatment is required, we recommend an appropriately qualified specialist.
Can you help my HOA evaluate multiple ash trees?
Yes, a scoped property review can look at priority areas, access, possible removal staging and optional photo or map documentation. Any tree-by-tree inventory, formal arborist report or pesticide work should be specified separately and undertaken by qualified professionals.
Worried about an ash tree? Let’s look at your options.
Tell us where the property is, what you’re seeing and whether your goal is to preserve, remove or plan for replacement. We’ll discuss what kind of assessment makes sense.
Your nearest town, number of trees, photos of the full crown, bark, and leaves (if safe), and when changes began.
Tell Us About Your Ash Trees
Reach out to share the tree symptoms, property location and your goals for preservation or removal.
Share your location, approximate tree count, symptoms and goals.
Call to discuss your concerns and the right next step for your property.
We’ll confirm assessment scope and any fees before arranging an on-site visit.
Colorado State Forest Service EAB ↗
CSFS Homeowner Guidance ↗
CSU Extension ↗
CBS Colorado Report ↗
Educational information only, not a definitive diagnosis, licensed pesticide recommendation or formal tree-risk assessment. The CBS video belongs to CBS Colorado and is embedded from its official YouTube channel.