When trimming makes sense
- Dead branches over the driveway, deck or roof.
- Limbs rubbing shingles or gutters, or hanging low over the sidewalk.
- Young trees that need one main leader picked now, before it costs more later.
- Storm-torn stubs that need a clean cut so they don't rot.
What good work looks like
Cuts are made just outside the branch collar, the swollen ring where a branch meets the trunk. Weight is reduced by cutting back to a side branch, not by stubbing off the top. Ask the crew not to "top" the tree: the new growth from topping cuts is weakly attached and tends to fail. Ask for climbing without spikes on a tree that's staying.
Power lines: who trims what
Street lines: ComEd trims around its distribution lines on a 4-year cycle plus mid-cycle work, following ANSI A300 (ComEd FAQ). The wire to your house: ComEd doesn't do routine trimming there, but it will drop or de-energize the service line for free so your contractor can work safely. Call 1-800-334-7661 at least 5 days ahead (ComEd). Near primary lines, ComEd says the work needs line-clearance-qualified trimmers under ANSI Z133.1 (ComEd tree trimming). Ask your crew if that applies.
Parkway trees
Joliet says only a certified arborist, or workers supervised by one, may prune parkway trees (Joliet Forestry). If a parkway limb is the problem, call the City at 815-724-3650 rather than paying someone to cut it.
Timing
Late winter, while trees are dormant, is the usual time for structural pruning of most species, and branch structure is easy to see. Dead or hazardous limbs can come off any time. For oaks, Joliet Forestry says prune before April 1 or after November 1 to avoid oak wilt (Joliet Forestry).
Pruning by season in Joliet
Late winter
Structural pruning while dormant. You can see every branch, and wounds close fast in spring.
Before April 1
Last call for oaks. Joliet Forestry says to prune oaks before April 1 or after November 1 to avoid oak wilt (source).
Summer
Deadwood shows clearly once the tree leafs out. Clearance cuts over roofs and drives.
After storms
Clean up torn stubs quickly so decay doesn't start at a ragged break.
What the City recommends
Joliet's own tree-care tips: cut off dead, crossing and rubbing branches and trunk suckers; cut close to the branch base, about a quarter inch away, without leaving a stub or cutting into the collar; and mulch 3–4 inches deep in a flat doughnut, never a cone against the trunk (Joliet Forestry).
Questions to ask a crew
Will you use reduction cuts instead of topping?
Do you climb with spikes on trees that are staying? (You want no.)
Are your trimmers line-clearance qualified if wires are in the canopy?
Do you need ComEd to drop my service line first?
What happens to the brush?