In the name of festivity countless people place wires filled with electricity on trees, bushes and other vegetation this year.

The irony lies, however, in the fact that, trees and vegetation are among the leading causes of power outages, according to ComEd. 

Of course, decorating trees and more with approved holiday lights is perfectly safe. But keeping trees a safe distance from power lines in a place like Northbrook, which has tens of thousands of trees of nearly every type, is a year-round activity for the utility. 

Evidence of that was clear on a recent Friday when a six-man crew was cutting back trees on Oak Street after a recent vegetation-related power outage.  

"These are junk trees, box elders, mainly, and some mulberries," said a crewmember, who preferred to remain anonymous due to corporate policy. Assisted by three large trucks, the crew was cutting back any tree limbs that had grown in the direction of the wires strung between utility poles.

"This year alone, more than 790,000 customers have been impacted by tree or vegetation-related power outages," said ComEd spokesperson Krissy Posey.

Vegetation management, as it's known in the industry, is carried out by subcontractors like the ones at work Friday, who've been specially trained to prune trees near power lines as well as other components of ComEd's infrastructure. 

According to the utility, if you're a homeowner here with trees that are tall enough and in proximity to power lines, you can expect to see one of their crews trimming back trees and vegetation where you live every four years or so, the company's cycle for regularly scheduled tree pruning. 

"They have done [tree trimming in] our back yard," said Dave Flinn, a 16-year resident of Butternut Lane. "I have never had a problem with it. I figured it was one less thing for me to trim."

ComEd emphasizes that consumers should never try to trim trees or anything else that's in proximity to utility lines, because of the risk of electrocution or other hazards.

To prevent power lines and trees from contacting each other on your property—and eliminate the need for such tree maintenance in the first place—ComEd recommends planting trees and bushes that grow less than 20 feet high, like dogwoods or crabapples. 

Trees growing higher than 30 feet—such as maples, elm, Blue Spruce, oak and a variety of pines—should never be planted under or near power lines.

According to company spokesperson Posey, there's more to ComEd's commitment of delivering safe and reliable service to its approximately 3.8 million customers across Northern Illinois. More than 70,000 miles of power lines run across the utility's 11,400-square-mile service territory, and those areas, too, must be kept clear of vegetation. This entails not only pruning of trees but also regular mowing of grass between the April and October.

According to Posey, the ComEd spokesperson, after the East Coast blackout of 2003, state and federal authorities placed a greater emphasis on keeping distance between high power lines and trees and vegetation. That power outage left millions without power in numerous states.