Minneapolis is known for its extensive urban tree canopy, with thousands of trees lining city streets and filling parks. However, many residents have noticed odd, V-shaped gaps in the branches of trees planted beneath power lines.
This unsightly pruning is necessary to keep the trees from interfering with overhead utility lines, begging the question: Why does Minneapolis keep planting large trees under power lines if they’ll just be disfigured later?
What causes the odd shapes in trees near power lines?
The misshapen trees are the result of a pruning technique called “directional pruning.” This involves selectively removing whole branches back to the trunk to direct the tree’s future growth away from the utility lines.
While this pruning method prevents branches from contacting the lines, it gives trees an unnatural, unfinished look compared to normal pruning practices.
Why can’t trees grow naturally near power lines?
Trees naturally grow in width as well as height. If left unpruned, their branches would grow into and around overhead power lines. Tree branches rubbing against lines in windy weather can cause damage and lead to fallen lines and power outages.
Trees that fall on lines pull the cables down with them. To prevent hazards, trees near lines must be pruned to create clearance.
Who is responsible for pruning trees near power lines?
Utility companies like Xcel Energy are tasked with line clearance pruning. Their contractors inspect trees near infrastructure every few years and prune according to national safety standards.
Plants that outgrow the available space may be removed and replaced with smaller varieties. Homeowners can prune small trees on their properties away from lines, but should not attempt to prune larger trees.
How did so many large trees end up under wires?
In 2000, Minneapolis had a plan to bury all power lines underground while replanting trees lost to disease. When this didn’t happen, small trees continued being planted under wires, eventually growing too large for the space.
The city now plants only small, mature trees under utility lines, reserving larger species for open areas.
What do residents think about the oddly-pruned trees?
Many Minneapolis residents view the uneven shapes as unsightly, a waste of good trees. They recognize the trees still provide some shade, but wish they could grow naturally.
However, keeping trees and overhead lines separate is necessary to prevent fallen branches during storms. It’s an ongoing challenge to balance aesthetics and function when landscaping near infrastructure.