Washington area residents tend to think about the metropolis’s imperfect system of electricity delivery when it fails, as it did spectacularly on the night of June 29 with the arrival of a broad, fast-moving storm we now know as a derecho.
Todd Bolton, as the arborist for Takoma Park, is mindful every day of the precarious coexistence of the urban forest and the power lines strung up on poles 25 to 35 feet in the air. On some corners in this historic little city, so many wires seem to be held aloft that you might think you are looking up to some mystical dreamcatcher, though one that seems to prefer collective nightmares at times of hurricanes, tornadoes, derechos, wind shears, ice storms and the occasional Snowmageddon.
We don’t perch domestic gas lines or water mains up in the elements — they’re snugly buried beneath the road — so why power cables? The short answer is that it’s expensive to bury them, but it has to do with history, too. Bolton eyed a map of Takoma Park on his desk computer that shows how the suburban community on the northern tip of the District grew from its incorporation in 1890.
Many of the city’s oldest neighborhoods received basic electricity supply in the first decades of the last century at a time when trees that grew from the mid-19th century were already of great height and girth. A single, innocuous power line brought power well below where these lofty giants began to branch. But during the course of the 20th century, homes became loaded with air conditioners, refrigerators, washer-dryers and other appliances, requiring an increasingly powerful network of electricity transmission and distribution. At the same time, new development led to wholesale removal of old trees and the planting of new ones that were destined to grow amid the utility wires.
Takoma Park, with its leafy neighborhoods of old houses, is like so many other communities of suburban Maryland, the District and Northern Virginia — cozy and settled but with an uneasy alliance of deciduous shade trees amid the aerial power grid. (Telephone and cable lines piggyback on the poles, themselves the carcasses of old pine trees.)
If you live in one of these neighborhoods, you don’t have to go far to see that in the struggle between shade trees and power lines, the trees might win the storm-by-storm battle, but they’re losing the war with the utility companies’ tree trimmers. In my neighborhood in Alexandria, which lost power for six days after the derecho, I can look out to an old oak tree whose central leader has been removed to leave lower branches that have turned skyward to the light to form a 60-foot “U.”
A few blocks away, there is a Chinese elm that has been rendered as a Texas longhorn. Nearby, two silver maples in someone’s front yard have lost their natural canopy, replaced by a towering, crescent-shaped hedge that curves around the power line ofDominion Virginia Power.
Check out Pepco’s Web site and you will find a guide to line clearance that sugarcoats the necessary butchery by conflating universally correct pruning techniques with dismemberment, namely the sawing off of a tree’s central leader or the removal of a whole side of a crown. This might be necessary to keep tree limbs away from lines, but it leaves the oak or maple or sweetgum — name the species — in a state of mutilation. The guide has wonderfully upbeat and persuasive language and compares the radical pruning regime with an older approach of topping trees — reducing a canopy to an arbitrary size. This worked for one season, until the tree responded with a mass of weak wooded shoots from the area of the cut — suckers or, more accurately, watersprouts.
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