INTEGRITY IN ACTION
Thornton Tree Service Company
Serving Thornton since 1978.
Keep Informed About Trees
Ross Tree believes in educating its customers about tree and plant healthcare. Our general manager, an ISA-certified arborist, has over 30 video blogs on YouTube. Homeowners use the Ross Tree Insect Calendar to identify pests munching on their yard trees. We have posted over 80 blogs about trees on our website since 2019. Ross Tree sends out a quarterly email newsletter to its customers.
Thornton Tree Programs
Thornton Forestry is dedicated to the ongoing stewardship of trees throughout the City. Click here for more information about the City’s tree programs.
Emerald Ash Borer
Currently, the EAB is not found in Thornton, Colorado, but has been detected across the Denver metropolitan area. With confirmed cases in neighboring cities, experts consider it a matter of time before it arrives in Thornton. The time to act is now because Ash has no immunity to the EAB. Property owners are generally responsible for managing and treating the ash trees on their own property. Check out the Ross Tree EAB Handbook to understand your treatment options.
Tri-Level Fertilization Program
Ross Tree started its popular Tri-Level Fertilization Program in 2024. We use proprietary feeding formulations to help trees flourish in Denver’s arid climate and poor soils. The program has three feedings per year rather than two.
Thornton Tree Services
We work in the order that usually serves a tree best: health first, then pruning, then removal.
Plant Health Care
Our arborists diagnose pests, disease, and soil problems, then treat them. That includes emerald ash borer treatment, systemic injections, and deep root feeding.
Tree Pruning
Standards-based pruning removes deadwood, reduces risk, and keeps the tree’s structure sound without over-cutting it.
Tree Removal
When a tree is dead, hazardous, or too far gone to save, we remove it, including large trees near homes. We handle street closure permitting when a job needs it.
Which Day Do We Work Your Neighborhood?
Our estimating arborist visits each part of the Denver metro on a set weekday, based on ZIP code. In Thornton:
Tuesday: 80229, 80233, 80241, 80260, 80602
Not sure of your ZIP? See the ZIP code lookup, or request a complimentary estimate and the form will show your next available dates.
Thornton Frequently Asked Questions
Who is responsible for the tree between the sidewalk and the street?
In Thornton, trees in the public right-of-way are generally managed by the city. Check with Thornton’s forestry or public works staff before pruning or removing one, and call us if you want an arborist’s opinion on its health first.
Should I treat or remove my ash tree?
Emerald ash borer is not yet confirmed in Thornton, but it has been detected across the Denver metropolitan area. Ash trees that still have a mostly full canopy can usually be saved with treatment. Trees that have already lost much of their canopy are usually better removed. Our arborist can tell you which applies on a complimentary visit. The Ross Tree EAB Handbook explains your options.
Are you licensed and insured?
Yes. Ross Tree is licensed, insured, and BBB A+ rated, with two ISA-certified arborists on staff. Our guide on how to choose a tree service lists what to check with any company.
How do I schedule an estimate?
Use the request service form or call 303-871-9121. You don’t need to be home for the visit.
Nearby Areas We Serve
Ross Tree also works in Brighton, Northglenn, Westminster, Commerce City, and Broomfield.
Request Service — Ross Tree
The Effect of Heat on Trees
High temperatures increase respiration in trees from leaves, stems, and flowers as they try to dissipate heat. Their porous lenticels also exchange gases between the atmosphere and their internal tissues. During hot days, trees release moisture into the atmosphere rather than using it for growth and storing food. Continuous hot weather stress trees as they two actives become out of balance.
Winter Tree Watering
In the winter, the root systems in deciduous and coniferous trees are active, so they need water. When temperatures are above freezing, their roots seek water and nutrients and store them so the tree can produce spring foliage.
Ross Tree Company
Ross Tree is a locally owned and licensed Denver tree company that has been in business since 1978. We offer tree pruning, tree insect control, and plant health care services. Why not call a licensed, insured, trusted tree company with an A+ BBB rating?