Violent storms last month and a deadly incident two weeks ago are amplifying the danger presented by falling trees and tree limbs, which can be a hazard to houses, cars, people and power lines.
On July 17, a 64-year-old Reston man was crushed to death by a 100-foot oak tree that fell on his car in Great Falls. An arborist with the Virginia Department of the Environment said the tree was rotten on the inside, but no one had called to complain about the ivy-covered behemoth in the many years it stood along Georgetown Pike.
Dying trees are a hazard in themselves, but experts said people need to watch out even for the healthiest trees, especially after severe weather — something the D.C.-area has had no shortage of this year.
At the end of June, a rare derecho storm tore through the mid-Atlantic region, bringing with it 60 mph winds that ripped roofs from homes and knocked over thousands of trees and pulled down electrical lines. Nearly 30 deaths nationally were attributed to the storm, including one 90-year-old woman in Virginia who died when a tree fell through her roof, and a tree-trimmer working in Garrett County, Md., who fell to his death trying to remove debris. A D.C. woman was paralyzed after a tree landed on her while she was riding her motorcycle during the storm.
Several thunderstorms have passed through the area since the derecho. While they have not been as strong as that storm, they still have knocked out power and shaken already battered trees.
“Lots of times we have severe storms and trees come down all over the place,” said Lew Bloch, a member of the American Society of Consulting Arborists who lives in Potomac. “Then weeks or months later, other trees come down that are injured but not destroyed.”
The types of injury Mr. Bloch referred to can range from a tree that is leaning over, to a split trunk or loosening roots.
The trouble is knowing where to look for this damage.
“Sometimes it’s easy to notice and sometimes it’s not,” Mr. Bloch said. “If it’s a tree in somebody’s lawn and it’s the only tree there, you can discover these things.”
Where things get dangerous is when trees are in heavily forested areas bordering roads owned by the state or local government.
While municipalities have a duty to inspect trees along the road, “it’s practically impossible for somebody to walk up and down the highway inspecting trees,” Mr. Bloch said. “You can’t spot everything doing this.”
Healthy trees fall, too
More than 400 people were killed from 1995 to 2007 by wind-damaged trees, according to a 2008 study published by Spring Science and Business Media. Almost half were killed by trees that fell on them while driving, or they drove into a fallen tree knocked down by heavy winds.
The challenge for municipalities to monitor their trees might have contributed to the death of 64-year-old Albert Carl Roeth III, as he drove through Great Falls on a Tuesday evening after three days of severe weather.
Virginia Department of Transportation spokeswoman Joan Morris said the agency had not received any complaints about the century-old tree. But when it fell, exposing its roots and insides, she said it was obvious the tree “was clearly decayed.”
The state does not have a dedicated program to inspect for damaged trees, but instead relies on maintenance crews doing other work on the roadways and on observations from the public.
Maryland State Highway Administration spokesman Charlie Gischlar said his agency also works with the public, as well as its own roads crews and power companies, to identify any trees at risk after a storm.
Along with regular tree trimming, road crews out doing other work can flag trees that look injured or have branches at risk of hurting someone.
Tree trimmers are sent to the tree at a later date, though if something is “an imminent danger, we will take it out immediately,” Mr. Gischlar said.
In the District, the Urban Forestry Administration employs 16 arborists to maintain roughly 140,000 street trees.
The department, which falls under the city’s Department of Transportation, regularly prunes and removes dying trees, spokesman John Lisle said. It also relies on residents to report unhealthy ones.
He warned that is not always enough during a strong storm though.
“It’s also important to keep in mind we’ve seen a lot of healthy trees come down and healthy tree branches snapped off,” Mr. Lisle said.
In October, a 35-year-old man was killed by a falling branch as he walked from his house on Adams Mill Road in Northwest. The tree was not visibly in need of removal.
Some residents take that message to heart. Mount Pleasant resident Bill Panici has worked to save neighborhood trees from Dutch elm disease since the late ‘90s when he started the Adams Mill Road Elm Tree Project. The organization raises funds every other year to prevent the spread of the elm bark beetle by injecting healthy trees with a fungicide.
But even vigilant local organizations cannot prevent all problems with trees.
“As recently as the spring and summer prior to that we had pruned some dead limbs out of a couple of the elms on the block,” Mr. Panici said. “Our Ward 1 arborist, Janet Miller, examined the tree and determined that there was no way to know that the limb was a threat. The tree did not have Dutch elm disease.”
Three years ago, a woman and child were killed along Connecticut Avenue in Chevy Chase when a tree fell on their car during a powerful storm.
Have big trees checked
The derecho storm that wreaked havoc on the area ended up closing about 200 state roads for high water and/or debris, Mr. Gischlar said.
“It’s hard because we’re in a dry spell right now and the area has experienced very violent, heavy downpours,” Mr. Gischlar said. “Something like these types of storms, they bring very violent, hot and hazy weather. And with a cold front, it does nothing but make vicious thunderstorms.
The problem then, Mr. Gischlar explained, is that with the right combination, not even healthy trees are safe.
“With the right conditions — even a healthy tree — they’re going to fall,” Mr. Gischlar said. “We do everything we can to keep that from happening.”
The odds of a tree falling on a person and killing them are pretty small, Mr. Bloch said, “but when it happens, it’s big news.”
The derecho was a kind of storm he had never seen. Couple that with the fact that severe weather, such as thunderstorms, tend to happen more frequently in the summer, and tree problems likely are not over for area residents.
“Any time you have a storm event like that, those trees crash down and they’re gone,” said Scott Aker, who is the head of horticulture at the National Arboretum. “But storm events like that also do some more subtle damage to trees.”
Mr. Aker said it is a good idea for homeowners after a bad storm to have their trees assessed by a certified arborist.
An arborist can check to see if the branches and top of the tree are balanced, can check the root system, and look for small cracks that are hard for untrained eyes to see.
Homeowners can do some review, such as looking for any obvious leaning or breakage, or thumping a rubber mallet against the trunk to determine if it is hollow — a sign of decay.
“It’s the smart thing to do right now,” Mr. Aker said. “You can look yourself, but it’s better to have a certified arborist. It’s worth every penny. It’s so much nicer to take [a tree down], instead of having it come down on your house or car.”
Does insurance cover it?
Considering standard insurance policies, however, homeowners may prefer to have a tree fall on their deck instead of their daisies.
According to Michael Barry, a spokesman for the Insurance Information Institute, standard homeowner insurance policies cover trees that fall on any structure, such as a house, garage or shed. If a tree simply falls in a yard, the policy likely doesn’t cover the clean-up unless it’s blocking a driveway.
“Wind, fire, and theft are the three core coverages,” Mr. Barry said. “Homeowners insurance covers every structure on your property.”
The same goes for car damage. Mr. Barry said anyone with comprehensive insurance — which roughly 80 percent of policy holders carry — is covered.
Should a tree fall onto a neighbor’s house, or if a home is struck by a tree from another yard, “where the tree lands is where the claim is filed,” Mr. Barry said.
Compared to the 5.8-magnitude earthquake that struck the city 11 months ago, the derecho “is a significant event from the insurance industry’s perspective,” Mr. Barry said.
“Beyond the National Cathedral and Washington Monument, there wasn’t a significant amount of damage once you got outside Louisa County,” he said, referring to the Virginia county at the epicenter of the quake. “The claims pay out from the derecho is going to be in the millions of dollars.”
• Emily Hatton contributed to this report.