Planting trees is important. But planting the right trees in the right places is even more important.

That's the message that utilities are trying to convey in the wake of severe summer thunderstorms, most notably the derecho that tore through the Mid-atlantic in late June. That storm left hundreds of thousands of people in the Chesapeake watershed without power, some for more than a week.

The storm arrived a few years after many cities and towns in the watershed set ambitious tree canopy goals. Counties and towns have been busily planting trees in the rights-of-way and creating a boulevard look wherever possible, with hopes of absorbing nitrogen from the air, soaking up stormwater runoff and improving habitat for various urban bird species. Governments have been encouraging property owners to plant trees as well, and local environmental groups in several cities offer free trees to neighborhoods and individuals.

But big trees can cause big problems. And some of the public's favorites — elms, ashes, oaks, maples, sycamores and tulip poplars — cause the biggest ones. Utilities' standard practice is to travel house-to-house and trim trees every four years if they are too close to the power lines. But they can't force homeowners to allow them to access their properties for trimming, and property owners are often reluctant to let the utility remove a favorite tree entirely.

"It's one thing to trim the limbs, but it's another when you can't take the trees that are attached to them out of the ground," said Rob Gould, a vice president at Baltimore Gas and Electric. "What we saw repeatedly through the derecho is whole trees that have come down on the lines. And when you have these real severe storms, when you have these trees off the right of way, there's not much you can do."

Unable to change past tree planting practices, utilities such as BGE are trying to guide future plantings. They post "right tree, right place" recommendations on their websites, and encourage private property owners to call 811 — the Miss Utility line — before they dig. The utility's foresters have visited local garden stores to talk about putting the right trees in the right places. And the foresters serve on many community and county forestry boards, offering advice on what trees to plant.

Good trees for any place include dogwoods, crepe myrtle and redbuds, said Danny Davis, BGE's supervisor of forestry operations. Davis recommends that no trees be planted near transmission lines, which carry more than 100,000 volts of electric current.

Bill Rees, business operations consultant for forestry management for BGE, said the ambitious tree canopy goals are generally not a problem. BGE crews can trim trees in the critical areas, typically 1,000 feet from waterways. They can remove trees there, too, and take on the job of replacing them. Utilities typically can weigh in on what trees are appropriate for large construction projects. Developers that have to plant trees as part of a mitigation plan consult with counties and towns, who share the plans with the utilities.

Utilities also work closely with the state, said Marian Honeczy, the supervisor for urban and community forestry with the Maryland Department of Natural Resources. Together, Honeczy said, they make sure the right trees go in the right places in the vast publicly owned forests and right of ways. If individuals inadvertently plant the wrong types of trees on those lands, the utilities can require them to remove the trees.

"You can plant trees near utility lines," she said. "You're not looking at oaks and maples and all that, but you're still getting tree coverage."

New large developments and publicly owned land cover a lot of ground. But, Honeczy said, most cities and towns can't meet canopy goals without homeowners doing their part. And that's where it can get tricky for the utilities.

"What we're finding is that citizens get attached to trees and may not want one removed, even if it's a hazard to other people and property," she said. "If a tree is going to damage people and property, then it needs to be removed. You have to be open to the health of the tree."

Sometimes, the homeowner wants to remove the tree, but the municipality doesn't make it easy. That can be the case in Annapolis, where homeowners need a permit to remove a tree if they live in the historic district. They also need a permit elsewhere if the tree is less than 25 feet from a city right-of-way or if the tree is in a forest conservation area.

Just because a tree is large, or looks precarious to a homeowner, does not mean the homeowner has the right to remove it, said Jan van Zutphen, Annapolis' forester.

"People call me. I have a document that states what's needed for tree removal. I might ask for a licensed arborist to prepare a report. If the report says it's healthy, then we may deny the permit," he said. "The reason for that is in light of the canopy goal."

Annapolis has a goal of a 50 percent tree canopy by 2036, and they need private landowners' help to achieve it.

Zupphen said city staff is in regular contact with BGE foresters.

"We try to work with them so that trees can be preserved. It's kind of a fine line," he said. "It's a back and forth, particularly in light of the pressure utilities are under. It's not always easy."

Trees are an important component of Bay restoration, and are likely to become increasingly important as several cities in the watershed embrace green infrastructure to tackle stormwater. BGE's Davis and Rees say they are supportive of trees, just as long as the right ones are in the right places.

And what of the trees the birds plant? The "volunteers" — which can include mulberries, walnuts and maples — can overtake yards, their canopies growing over the power lines.

For those volunteers, Rees said, the best course of action is paying attention.

"If you know it's a tree that's not appropriate, you really should deal with it when it's small," he said. "It's a lot easier to remove it then."