Power outages are such a problem for the area that the Pikesville-Greenspring Community Coalition has a committee focused on nothing but the issue. Noel Levy, the committee's chairman, said "hardly a week goes by in Pikesville, hardly a week, when somebody isn't losing power somewhere."

He suggested that decades-old equipment in dire need of replacement is more to blame than trees.

Barry Holt Blank, first vice president of the coalition, agreed. But he acknowledged that the tree work, while not a panacea, has made a difference.

"We let BGE know that we recognize that they've spent a ton in our neighborhood and things are better than they were," Blank said.

The dominant emotion about tree-trimming and removal in the Baltimore area used to be dissatisfaction, changing as it did the look of yards, streets or entire neighborhoods. Residents occasionally sought temporary restraining orders to try to protect trees on their property. Carroll County's commissioners, after fielding complaints, asked BGE in 2005 to halt work along Route 140.

Then one storm after another hit Maryland. The twin snowstorms in 2010. A January snowstorm and Hurricane Irene in 2011. The derecho and Sandy this year.

That change has brought more and louder customer complaints about reliability. It has also caused what Gould called a 180-degree turn in customer opinion on tree maintenance.

Now some homeowners are asking BGE to take down their trees, he said. In cases where property owners aren't so thrilled, community leaders have suggested to him that a little neighborly peer pressure might be applied. (When trees pose a hazard to lines but aren't growing into the utility right of way, BGE's hands are more or less tied if it can't get the owner's OK.)

And then there are the customers — like the nuns in Baltimore — who take the expense of tree trimming and removal upon themselves.

"I regret that it had to come because the lights go out so often in storms, but I'm grateful that the shift has happened, because it allows us to accomplish our mission more effectively," BGE's Daschbach said.

But for tree lovers, the change is unwelcome.

Nina Beth Cardin, a rabbi who directs the Baltimore Orchard Project, said trees are so critically important to the environment that two at a minimum ought to be planted for every one cut down. The goal should be to put wires underground, which would also cut down on visual blight, she said.

Cardin lives in Pikesville, where BGE has been cutting and trimming assiduously. She lost seven massive white pines and one locust tree in her front yard this summer. She also lost power for a week after Irene and eight days post-derecho. Her point isn't that trees are more important than energy, but that it's wrongheaded to pit the two against each other.

"It should not be either power or trees," said Cardin. "We've set up an unhealthy competition."

An overhead system is more prone to outages than one underground. About 80 percent of BGE's underground distribution lines functioned through each of the past three major storms, compared with just over half its overhead lines, according to the grid task force.

For distribution lines that are partly above and partly below, storm performance fell between the two extremes — a reminder that customers with underground lines can fall victim to tree-related outages, too.

And while proponents say the long-term savings would be substantial, large-scale "undergrounding" could come with a huge upfront tab.

The state's grid task force, citing a utility trade group, said such conversions "can cost five to ten times more than comparable overhead construction." It recommended undergrounding in select cases but suggested that aggressive tree-trimming was the most effective move.

The bottom line, as the task force saw it, is "if the branches don't fall, the lines don't break."

Daschbach said he wants people to know that the utility takes power reliability and the importance of trees seriously. There's an innate tension: It's the towering specimens that pose a problem for lines, he said, but "those mature trees are the ones that are pretty majestic."