Landscaping
When (and How) to Trim Trees in Colorado
Good pruning is mostly timing and one anatomical rule. Here's when to cut, where to cut, and an honest line between DIY, handyman work, and the jobs that need a climbing crew.
- Published
- August 15, 2026
- Reading
- 7 min
- By
- BigBoy Builders
Timing: Dormant Season Wins
For most Front Range trees, the pruning window is late winter — roughly February into early April, after the deepest cold but before buds break. The tree is dormant, its structure is visible without leaves, insects and disease organisms are inactive, and the cuts are ready to seal as soon as spring growth starts.
| Situation | When to cut | Why |
|---|---|---|
| Most shade trees (maple, ash, honeylocust) | Late winter | Dormant, visible structure, low disease pressure |
| Dead, broken, or hazardous branches | Immediately, any season | Hazard removal doesn't wait for the calendar |
| Spring-flowering ornamentals (crabapple, lilac) | Right after they bloom | Winter pruning removes the flower buds |
| Elms and fruit trees | Dormant season only | Cuts in the growing season invite beetles and fireblight |
| Evergreens | Sparingly, late winter if needed | Most conifers need little pruning and don't refill gaps |
| Light shaping and clearance | Any season in moderation | Small cuts on healthy wood are low-risk year-round |
The One Rule That Decides Everything: the Branch Collar
At the base of every branch is a slightly swollen ring where it meets the trunk — the branch collar. That collar contains the tissue that grows over and seals a wound. The whole craft of pruning reduces to one rule: cut just outside the collar — never flush with the trunk, never leaving a stub.
- A flush cut removes the collar itself; the wound can't close, and rot walks into the trunk.
- A stub left beyond the collar dies back and becomes a rot straw pointed at the heartwood.
- A collar cut leaves a clean circle that grows closed in a season or two — no paint or sealer needed. On branches heavier than an inch or two, use the three-cut method (undercut a foot out, top cut to drop the branch, then the finish cut at the collar) so falling weight can't strip bark down the trunk.
How Much to Take
Never more than about a quarter of a tree's live canopy in one year — and less is almost always better. Topping a tree (chopping main limbs to stubs to reduce height) is not pruning; it produces weakly attached regrowth, decay in every stub, and a tree that's more dangerous in five years than the day it was topped. If a tree is genuinely too big for its spot, the honest options are proper crown reduction by a qualified arborist or replacement.
Who Should Do the Cutting
- Hand-pruner and pole-saw work from the ground — anyone with the branch collar rule and a sharp blade.
- Clearance around rooflines, gutters, walkways, and lower canopies — handyman-sized work; this is what our tree trimming service covers, debris hauled away.
- Anything requiring climbing, rigging, or a chainsaw overhead — dedicated tree service with the insurance to match.
- Anything within ten feet of a power line — utility line-clearance crews only. No exceptions, no ladders.
Questions / Field Notes
Frequently asked questions
Branches on the list?
BigBoy handles the handyman-sized majority of tree trimming — clearance, dead branch removal, shaping — with the debris hauled off.
When it's past DIY
The services this connects to.
In practice
Where we've done it.
Built different.
Questions this guide didn't answer?
Give us a shout — if it's outside our lane, we'll say so.
Call · (719) 203-9435
Write · help@bigboy.build
You talk to the person doing the work.
