A sycamore limb resting on the wires above the back fence is a call to the utility, not a chore for a pole saw. Trees near power lines follow a separate set of rules from ordinary yard trees. Those rules decide who prunes, how far branches must stay from the wires and who cleans up afterward.
The details below come from SMUD, the publicly owned utility for much of the Sacramento area. If another company delivers your electricity, check its own vegetation rules, since each utility runs its own program.
Which Wires Count as High Voltage
Not every overhead line carries the same risk. SMUD explains on its trees and power lines page that high voltage lines usually run highest on the poles, and that poles or cross arms carrying them are marked with the words High Voltage.
Lower lines below the transformer carry less voltage. The service drop that runs from the pole to the house is lower voltage too. According to SMUD, those service lines get pruned only when branches put heavy strain on them or rub against them, and customers or their contractors can sometimes work around them safely.
Lower voltage does not mean safe to touch. Any line can carry enough current to injure someone, so treat every wire as live.
The Ten Foot Rule for Trees Near Power Lines
SMUD asks owners to follow a simple test. If a tree you want to prune or remove sits within 10 feet of a high voltage line, call the utility first. SMUD says it will inspect the line at no charge so the work can move forward safely.
That call protects the person on the ladder. It also protects the tree crew, the neighbors and the power supply for the whole street.
SMUD points anyone doing this work to Title 8 of the California Code of Regulations, Articles 37 and 38, the state electrical safety orders. Those orders explain why near line pruning belongs with crews trained for it.
Signs a Tree Is Growing Into the Wires
Look at the canopy from the street, not from under the tree. Distance is hard to judge from below.
- Branches touching or resting on any overhead line
- Leaves or twigs scorched where they meet a wire
- Lights that flicker on windy days
- A limb hanging over the line with visible cracks
- New sprouts heading straight up toward the conductors
Report what you see to the utility and describe where the tree stands. Take photos from the ground. Never climb the tree to get a closer look.
What to Ask the Utility
A short list keeps the call focused.
- Is the line near the tree high voltage or a service drop?
- Will utility crews prune it, or can a private arborist work there?
- How much clearance will the crew leave?
- Who removes the cut wood?
Write down the answers with the date and the name of the person you spoke with.
Utility Pruning on Private Property
Many owners are surprised when a door hanger appears. SMUD states that it notifies owners in person or with a door hanger before pruning a tree on private property. It also states that owner permission is not required, because the law requires the utility to keep its lines clear.
The same page lists the legal minimums. California Public Utilities Commission General Order 95, Rule 35, calls for at least 18 inches between vegetation and conductors carrying more than 750 volts. Public Resources Code sections 4292 and 4293 add larger clearances in areas where CAL FIRE is the direct protection agency, which generally means non urban land.
Utilities usually cut well past those minimums. SMUD says it aims for about 12 feet between canopies and its overhead lines, and as much as 20 feet for fast growing trees such as mulberry or eucalyptus. Growth rate, sway in wind, line sag and the time until the next pruning cycle all affect the final cut.
If the shape after pruning bothers you, contact the vegetation planner named on the door hanger. Asking questions before the crew arrives works better than complaining after.
Planting Under Lines
The easiest conflict to fix is the one that never grows. State regulators offer a planting rule too. The California Public Utilities Commission suggests on its vegetation management page that a tree planted near lines should top out at least 10 feet below the closest wire at maturity.
SMUD sets a tighter rule for its transmission corridors. Only low growing groundcovers and shrubs under 10 feet at maturity belong in that right of way, which extends 10 feet outside the lines. Building or other improvements there require an application with SMUD first.
Check mature height on the plant tag, not the size in the nursery pot. A small tree grows fast once its roots settle in.
Storm Damage and Cleanup
Stay away from any line that has fallen or rests in a tree. Call 911 or the utility outage number right away, and keep children and pets back.
During outage work, SMUD crews may remove uprooted trees or broken limbs from the lines. Once the lines are clear, SMUD says final cleanup of storm damaged trees falls to the property owner. Budget for that hauling, and see the post on clearing old materials from a bed for how debris sorting works on a smaller scale.
Other Rules That Still Apply
Utility clearance does not override City tree rules. A City tree or a private protected tree can still need a permit for regulated work, so check with the City before any removal or major pruning that the utility is not doing itself.
Digging near a tree can also hit buried lines. Before planting a replacement or grinding a stump, contact 811 so utilities can mark what lies underground. The post on scheduling demolition before new work covers that step in order.
When you do bring in a private tree company for work away from high voltage lines, confirm its license and insurance first. The article on questions to ask about a landscaping contract lists the paperwork to request. More articles on permits and responsibility for trees near power lines sit in the tree rules category.