Planting large trees near power lines can cause years of conflict between homeowners and utility service providers over issues such as maintaining power supply, aesthetics, safety and tree health. For safety reasons and to minimize power supply disruptions, utility providers are obligated to keep power lines clear of growth within 10' of the line, both below the line and side to side.
The guideline for trees planted under a power line is that mature height should be 16 feet or less. Trees planted in power line adjacent areas should have a mature height of 25 feet or less. Unfortunately, there are few options for trees that stay under 16 feet. One way to broaden your choices is to consider small conifers, large shrubs and pendulous or weeping cultivars that do not have a strong dominant leader, as they can be staked to the appropriate height and left to ramble. If desired, some large shrubs can be trained to resemble small trees.
For great options on small conifers, check out the Iseli Nursery website. They are a wholesale conifer grower that services many local garden centers and nurseries. While not all of their trees are small, they have an easy to navigate website where you can get some ideas. When choosing a tree, be careful with the term ‘dwarf’. It only means that a cultivar is smaller relative to the size of its parent, and doesn’t necessarily mean it will remain small.
CLICK HERE for a printable list of small trees and shrubs that could be considered for planting in power-line adjacent areas along the Wasatch Front. In selecting the option that is right for your location, be sure to consider its cultural needs in addition to its mature height, such as hardiness, sun/shade preference, water needs, soil preference and tolerances.
If you are looking for more options or guidance on areas in addition to the Wasatch Front, Rocky Mountain Power has a booklet titled Small Trees for Small Places, by Randall Miller. It includes input from Utah tree experts, including Dick Hildreth and Dr. Mike Kuhns. It was created for use in multiple western states, so be careful to look at hardiness zones for your area.