A publication of the Virginia, Maryland & Delaware Association of Electric Cooperatives

Cutting Edge
Home | Cutting Edge | Planting Seeds of Safety

Planting Seeds of Safety

Protect new trees by putting them in safe places

March 2024

by Scott Flood, Contributing Columnist

“Why can’t they just leave my trees alone?”

If you’ve ever wondered that as you’ve watched a tree-trimming crew change the look of your favorite tree, you’ll find the reason in rural Ohio. At a little after 4 p.m. on the steamy Thursday afternoon of Aug. 14, 2003 — with everyone’s air conditioners cranked up to MAX — a sagging transmission power line in the Buckeye State came in contact with nearby tree branches. In minutes, 45 million Americans and 10 million Canadians had no air conditioning or any kind of electric power.

Whether you want to plant a tree, a decorative shrub or something else, it’s helpful to consider how it’s going to grow over the next 20 or 30 years. Consider both the eventual height and how wide the canopy of branches is likely to spread.

Transmission lines are a critical element of the U.S. power grid. These lines crisscross North America, some held up by slim poles, while others hang below towers resembling science-fiction robots. The giant wires suspended from both types can carry enough electricity to power more than a million homes, moving it from distant power plants to electric cooperatives and other users.

Federal regulators placed most of the blame for the 2003 blackout on technology that failed to reroute power properly after the transmission line touched the trees. But they also recognized the problem would not have happened if those trees had been a safe distance away from the line. The outage event led to strict rules that your electric co-op and other electric utilities are now required to follow to prevent large-scale blackouts.

Co-ops are required to document that every piece of equipment and every foot of their power lines are a safe distance from trees and other vegetation. If your home received a visit from one of their tree-trimming crews, it was likely because your trees were closer to power lines than the rules allow and are legally required to act.

Whether you want to plant a tree, a decorative shrub or something else, it’s helpful to consider how it’s going to grow over the next 20 or 30 years. Consider both the eventual height and how wide the canopy of branches is likely to spread.

Tree Service craft worker trim trees along a distribution line in New Hampshire, on a sunny fall day.

Electric co-ops and other electric utilities are required to document that every piece of equipment and every foot of power lines are a safe distance from trees and other vegetation.

For example, even small trees and shrubs should be planted at least 20 feet from power lines. If you can’t plant that far away, make sure you choose a species that won’t top out at more than 15 feet high. Trees that will be 40 feet high or less should be at least 25 feet from any electricity, and larger trees should be at least 50 feet away.

Thinking about what’s above the ground is only part of tree-planting safety. Before you grab a shovel and start digging, contact 8-1-1 to make sure you won’t accidentally cut into any underground utility lines.

Trees aren’t the only type of vegetation requiring thoughtful planting. If there’s a pad-mounted transformer in your yard, you might be tempted to hide it behind colorful flowers and neatly trimmed shrubs. Unfortunately, if there’s a problem, crews will need clear access to the transformer. That’s why it’s always a good idea to keep plantings at least 10 feet from the transformer’s doors and at least 4 feet from its sides. Otherwise, crews responding to a power problem may need to remove part of your landscaping.


Scott Flood writes on a variety of energy-related topics for the National Rural Electric Cooperative Association.