Drought Harsh on Urban Trees |
By Jennifer Lenhart and Mary Louise Schumacher
Scott Gravatt, grim-faced urban forester for Arlington County, set out early to visit the dead and the dying.
The man whose job is tending to 50,000 or so city trees tromped through Troy Street Park in South Arlington on Friday, eyes cast upward at browning canopies, dead leaves. Drought casualties. A dying white oak, 60 or 70 years old, normally would live many more years, but, weakened by lack of rain, the old giant was heading toward an early trip to the mulching machine.
"These trees, they are definitely all suffering," said Gravatt, who uses his background as a forestry major at Virginia Tech to manage the county's trees and to monitor the health of new and existing stock. "There aren't that many trees in Arlington or any developed community. When you lose the big ones, that's what hurts the most."
Struggling trees will get extra attention from members of Arlington's tree crews, but those that don't make it will have to come down.
Trees and seedlings are dying at an alarming rate this summer. The drought is affecting young and old trees in the city and the suburbs, as well as timberland and Christmas tree farms in the countryside. Doomed by the chronic lack of rain, many seedlings planted this year have died or been stricken by disease.
Reforestation efforts along the Chesapeake Bay and its tributaries are being stymied by the uncooperative weather.
Urban foresters, who take care of trees that live in challenging environments along sidewalks and in street medians--where roots don't have much space to spread and pollution hinders growth--are taking extreme measures. The town arborist in Leesburg rigged water-filled bags around the trunks of thirsty young hardwood and pine trees in hopes of keeping them alive.
"City trees have a very hard time," said Kathy Sevebeck, executive director of the Virginia Urban Forest Council and a forestry professor at Virginia Tech. "They're in a much harsher environment, so the drought hits them harder."
Arborists around the region who collectively have planted millions of seedlings--young trees without fully developed root systems--have tallied numerous fatalities. An estimated 60 percent of seedlings planted along Maryland state highways have perished this year, according to the Maryland Department of Natural Resources.
"It is impossible to put enough water out there on highway interchanges," said Mike Galvin, the department's urban operations manager.
The telltale signs of drought are everywhere in the tree canopies of the city and the suburbs. Yellowed edges of leaves signal scorch leaf. Crumpled and mud-colored leaves indicate brown leaf. These conditions, which are brought on by the drought, indicate that the roots aren't getting enough water to pass it along to through limbs. Trees that were diseased going into the drought may be less likely to survive when the two problems strike at the same time, Gravatt said.
And such conditions aren't necessarily fatal. At the park in South Arlington, he assessed a row of struggling 10-year-old maples, most of them with the beginnings of brown leaf, and planned to tell his tree crews to look in on them more frequently. Their fate, like that of the white oak, probably won't be known until spring when new leaves should bud.
"A tree can suffer an entire exfoliation and still come back in the spring," Gravatt said. "What I've noticed is trees that have other problems, insects or disease, the drought has compounded those, either pushing them to the edge or over the edge."
Local governments are doing what they can for urban greenery, sending water trucks out in the morning when water is less likely to evaporate, weighing the needs of trees against those of residents. The balancing act is painful for local governments such as Arlington County that recently have stepped up their tree-planting programs.
"We have indicated to the forestry guys that we definitely want the trees to survive this, but we're going to follow the same advice we're giving our citizens, which is not to water excessively," said Dick Bridges, an Arlington County spokesman.
In the shriveled countryside, survival rates haven't been as high as anticipated for more than a million seedlings that went into the ground this year along the shores of the Chesapeake Bay and its tributaries, part of a reforestation project initiated in 1996 by the Chesapeake Bay Commission.
"We've been doing seedling survival checks," said Don VanHassent, supervisor of forest stewardship for the Maryland Natural Resources Department. "Our foresters have gone out to check, and there are lots of fatalities."
An official tally won't be completed until later in the year.
The harvesting of timberlands--which annually produces revenue of $11.5 billion in Virginia and $1 billion in Maryland--isn't expected to slow down this year because of the drought. But forestry officials said they are doing field inspections earlier than usual in the spring-through-fall growing season to scout damage. And they are seeing many more dead trees than in wetter years.
Dana Malone, a Loudoun area forester with the Virginia Department of Forestry, inspected four tracts of pine and hardwood timberland last month and found that about 45 percent of the trees had died from poor growing conditions.
"It's certainly had a major impact on seedling survival," Malone said.
More than 75 Christmas tree farmers in Virginia and Maryland have had a grim season: They have watched Scotch pine, spruce and fir seedlings wither and die.
Tom O'Halloran, president of the Virginia Christmas Tree Growers Association and a tree farmer in Culpeper County, lost 3,000 of the 5,000 seedlings he planted this year, including all 550 Scotch pine plants.
Peter Holden, district liaison with the Loudoun Soil and Water Conservation District, said: "Christmas trees, they're hurting with the drought. If this is their first year, they've had it."
© 1999 The Washington Post Company