COLORADO MOUNTAIN PINE BEETLE ASSESSMENT
Mountain Pine Beetle
Assessment & Action Plan.
Is your pine forest under attack? We assess visible signs of mountain pine beetle activity, identify vulnerable trees and develop practical next steps for Colorado mountain properties.
Conifer • Evergreen • Ken Caryl • Pine • Jefferson & Douglas Counties
Illustrative field assessment guide • visual clues require interpretation
Don’t wait for a pine to turn red before asking questions.
Mountain pine beetles can attack a pine while its crown still looks healthy and green. Needles often do not fade until eight to ten months after a successful attack. By then, the window to protect that particular tree has generally passed.
A practical property assessment looks for bark-level evidence, host tree species, nearby activity and overall stand conditions. It also helps distinguish suspected mountain pine beetle activity from other bark beetles, drought stress and unrelated tree-health problems.
Stone Elk Land Services helps landowners understand the visible evidence, prioritize what warrants attention and plan sensible forestry work. When a definitive species diagnosis, arboricultural risk report or chemical application is needed, we recommend an appropriately qualified specialist.
Mountain pine beetle activity is a current local concern.
In its July 2026 update, the Colorado State Forest Service reported elevated activity in portions of Jefferson, Douglas, Park and other Front Range counties. Not every declining pine is beetle-infested, but early inspection can help landowners make better decisions.
Six clues that deserve a closer inspection.
These signs help guide an assessment, but no single visible symptom always proves an active mountain pine beetle infestation.
Popcorn-Like Pitch Tubes
Small white, pink or brown resin masses may appear where insects entered the trunk. Some attempts fail, so pitch tubes need context.
Fresh Boring Dust
Fine reddish-brown or tan sawdust in bark crevices or near the base can indicate beetle entry, even when resin is hard to see.
Woodpecker Activity
Flaked-off bark and concentrated woodpecker feeding may suggest insects below the bark, though they do not identify the species.
Yellowing or Red Needles
Crown fading is often a late sign. A green crown cannot rule out a recent attack; other stressors can also change needle color.
Galleries & Blue Stain
Characteristic tunnels, life stages and stained sapwood may help confirm an attack when accessible and inspected appropriately.
Tree Species & Lookalikes
Ponderosa, lodgepole and limber pines are important hosts. Ips and other insects can produce similar clues and require different considerations.
The details on the bark tell a different story than the crown alone.
Our assessment combines the visible symptoms with species, site conditions and seasonal timing.
Look closely. Interpret carefully. Prioritize intelligently.
Understand which tree species are present and where vulnerable stands occur.
Check accessible trunks for pitch tubes, boring dust, woodpecker evidence and exit holes.
Review the pattern of symptoms, timing and signs of insect emergence; recommend specialist confirmation if uncertain.
Look at tree density, competition, site conditions, safety and practical access for treatment.
Different trees call for different decisions.
The purpose of the assessment is not to recommend removing every pine. It is to identify reasonable, timely actions based on what the field evidence supports.
Identify, prioritize and plan safe removal.
Where a successful attack is likely, we discuss removal timing, access and handling of potentially infested wood. Proper treatment or disposal before the next adult flight can help limit further emergence.
There is generally no practical cure once a tree is successfully colonized.
Focus prevention where it makes sense.
We consider tree condition, nearby beetle pressure and stand density. Preventive products may be an option for selected uninfested trees, but should be discussed with a properly licensed applicator.
Preventive sprays are not a rescue treatment for already infested trees.
Build resilience beyond one season.
Appropriate thinning, species and age diversity, periodic monitoring and management of dead or declining trees can support a healthier, more resilient stand over time.
Every recommendation depends on site access, conditions and the agreed scope.
The calendar changes the best next step.
Mountain pine beetles typically fly to new hosts during summer. The Colorado State Forest Service notes that fall is a useful time to inspect and that infested trees should generally be addressed before the next flight.
Timing varies by location, weather and insect species. This is general guidance, not a fixed treatment schedule.
Know what you’re dealing with before you invest in work.
Designed to turn uncertainty about declining pines into a practical property-specific plan.
Discuss
Share your location, pine species if known, photographs and concerns before the visit.
Inspect
Review accessible representative trees, visible attack clues and stand conditions.
Prioritize
Separate suspected infestations from susceptible and lower-priority trees.
Recommend
Discuss timing, handling, treatment scope and any follow-up expertise needed.
A clear set of next steps for your property.
Documentation is tailored to the property and quoted assessment scope. Optional reporting and mapping can be added for larger or more complex sites.
Key visible signs, host trees and conditions reviewed during the visit.
Location notes or marked priorities for suspect and vulnerable trees, as scoped.
Removal, disposal, forest-thinning or monitoring considerations.
Practical seasonal priorities before the typical summer beetle flight.
Available field-service scope and estimating options for agreed work.
Site images, mapped treatment areas and aerial context when separately included.
See the forest as a system.
Not just one damaged tree.
For large parcels, complex terrain or HOA-managed landscapes, optional drone imagery and LiDAR can help document vegetation structure, canopy patterns, terrain and proposed work areas. Dated photos and maps can support planning and future comparisons.
Important distinction: aerial imagery and LiDAR do not, by themselves, confirm mountain pine beetle species or active infestation. Field observations remain essential; mapping options depend on access, safe flight operations and the agreed scope.
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Conceptual illustration only. Aerial mapping is an optional service and is not a lab diagnosis or insurance certification.
Local insight for mountain property owners.
Stone Elk Land Services works with homeowners, landowners and property managers on field-based pine beetle assessments and practical forest management discussions across the Colorado Front Range.
Outside these areas? Contact us with your approximate location and property size.
Mountain pine beetle: what you should know.
Can my tree be infested if the needles are still green?
Yes. The crown may remain green for months after a successful attack. The Colorado State Forest Service notes that yellow-to-red foliage commonly appears about eight to ten months later. Bark-level clues are useful for evaluating a potentially recent attack.
Do pitch tubes or brown needles always mean mountain pine beetle?
No. Pitch tubes can appear after unsuccessful attacks, and several bark beetle species or unrelated stressors can create similar clues. An assessment considers the tree species, evidence on or under the bark, crown condition and recent activity together. When the evidence is uncertain, further specialist identification may be warranted.
What time of year is best to inspect for pine beetles in Colorado?
Fall after the typical summer flight is an especially useful time to look for new attacks. Winter and early spring also allow time to plan suitable action before the next summer emergence. If you notice suspicious symptoms now, do not wait for a particular month to ask for guidance.
Can a tree be saved after a successful mountain pine beetle attack?
Generally no. Once a pine has been successfully colonized by mountain pine beetles, there is no practical treatment that reverses the attack. Early inspection helps distinguish trees that appear infested from healthy trees that may benefit from prevention or improved stand conditions.
How soon should an infested tree be removed?
For trees with active beetles, Colorado State Forest Service guidance generally favors removal and appropriate handling before adults emerge during the next summer flight. The right date and disposal method depend on local conditions, access and regulations. Trees that beetles have already left may still warrant removal for safety or forestry reasons.
Do you offer preventative spraying or pesticide treatment?
Our service focuses on field assessment, forestry planning and eligible vegetation work. Preventive insecticides, if appropriate for high-value uninfested trees, should be evaluated and applied by a Colorado-licensed pesticide applicator following the product label. We do not present spraying as a way to cure a tree that is already successfully infested.
Will you need to inspect every tree on my property?
Not necessarily. We first define the size and purpose of the visit. A smaller assessment may focus on specific suspect trees or representative areas. A broader inventory, tree-by-tree tagging, aerial mapping or formal report would need to be included in the quoted scope.
Can you help with wildfire mitigation documentation or reimbursement programs?
Where relevant, we can discuss forestry work scopes, dated photographs and optional mapping that may support mitigation documentation. Assistance programs, tax treatment and insurer decisions have their own eligibility and evidence requirements. An assessment alone does not guarantee funding, tax benefits or an insurance outcome.
Not sure what’s happening to your pines?
Tell us where the property is located and what you’ve noticed. We’ll discuss the symptoms, your concerns and the right next step for a mountain pine beetle assessment.
Nearest town, approximate acreage, number of affected trees, when symptoms appeared and whether there are recent removals nearby.
Tell Us About Your Pines
We’re happy to discuss what you’re observing and whether a site visit is appropriate. Reach out directly using either option.
Share photos and property details
Email us your nearest town, approximate acreage, and what you’re noticing on the trees.
303-475-4409
Call to discuss your concerns, service area, and available next steps.
Information is educational and does not replace a definitive laboratory identification, formal tree-risk assessment or licensed pesticide consultation. Site-specific recommendations depend on actual observations and scope.