As the five girls from Mrs. Fadgen's AP biology class worked, they talked about school, about guys, about pants.
They didn't talk much about the tree they were planting -- "a European hornbeam? Really?" -- but someday, when they're the mothers of teenage girls, they just might talk about what they did this day -- and wonder how this awkward, spindly teenager grew to be a 35-foot-tall shade tree on Willow Avenue in Castle Shannon.
On April 27, students from Keystone Oaks High School were among nearly 50 residents who helped plant 19 trees provided free by TreeVitalize Pittsburgh, a 5-year-old partnership led by the Western Pennsylvania Conservancy. Over six weeks this spring, staffers and volunteers planted 1,887 trees in 13 Pittsburgh neighborhoods, 12 Allegheny County municipalities and several city and county parks. Since the program's start in April 2008, more than 19,000 trees have been planted. During the fall planting season that begins in late October, TreeVitalize will easily surpass the 20,000-tree goal set in 2008.
To qualify for trees, communities send residents to attend Tree Tenders classes offered several times a year by Tree Pittsburgh. The communities also must promise to regularly water, prune and maintain the trees. The next Tree Tenders class is 10 a.m. Sept. 7 at the Millvale Community Center, 416 Lincoln Ave., and Sept. 20 is the deadline for communities to apply for trees to plant next spring. TreeVitalize is a joint project of the county, the city, Tree Pittsburgh, the Pennsylvania Department of Conservation and Natural Resources, and the Western Pennsylvania Conservancy.
"We have developed an urban forestry program that works for our city and our region. We have a high level of community involvement," said Jeffrey Bergman, director of TreeVitalize.
At classes held periodically throughout the county, residents learn which trees perform best in the area, how to prune and maintain them, and how to recognize diseases and other problems. They receive a recommended list of street tree cultivars that are also well-suited to front yards in Western Pennsylvania:
Small (15-35 feet at maturity): 'Spring Snow' crabapple, 'Winter King' hawthorn, hedge maple.
Medium to large (40-80 feet): 'Princeton Sentry' ginkgo, 'Shademaster' honey locust, 'Village Green' Japanese zelkova, 'Bloodgood' London plane tree, 'October Glory' red maple, sawtooth oak.
TreeVitalize foresters also sometimes choose other hardy ornamental trees that will fit beneath power lines. In Castle Shannon, volunteers planted redbud, flowering cherry, hawthorn, Kentucky coffeetree and European hornbeam. The latter is preferred over the native variety because it is tougher and has a narrower spread than its American cousin.
"Our foresters find the right tree for the right place," Mr. Bergman said in April as he eyed a site at the corner of Willow and Poplar avenues. "The European hornbeam is more conical and stays upright. There's not a lot of space here."
Several weeks before planting day, contractors had dug rectangular curbside pits measuring 10 by 3 feet, three times larger than the square wells where trees had been planted 30 years earlier. Many of those trees had died. Others were growing into their iron grates or their roots were lifting the sidewalks.
Mr. Bergman said foresters today know much more than their predecessors about planting and maintaining street trees. When selecting trees, their choices are sometimes guided by pest or disease threats. For example, TreeVitalize has never planted ash trees because of the effect the emerald ash borer has had on the large population of older ash trees in city and county parks.
TreeVitalize trees have an overall survival rate of 96 percent. It is highest in neighborhoods in which the people who planted the trees continue to care for them. That describes him and his Troy Hill neighbors, who planted elms in spring 2009, before he became director of the program. Trunks that were 2 inches wide four years ago are now 6 inches wide and stand 35 feet tall, he said.
"You would see your neighbor watering a tree and say, 'Oops, I'd better water one,' " he said.
Engaging residents in the process and turning them into Tree Tenders is a key to the project's success, Mr. Bergman said.
On planting days, TreeVitalize and Tree Pittsburgh staffers demonstrate how to safely move and place a balled-and-burlapped tree, how to cut the burlap and cage away from the root ball, and plant the tree at the proper depth. Then they backfill with topsoil, drive in two support stakes and tie the tree to them to help it grow straight. Finally, several inches of hardwood mulch is added to help keep weeds down and conserve water.
In Castle Shannon, four Tree Tenders supervised teams of volunteers as they planted. Within three hours, all 19 trees had been planted, and volunteers were eating donated food and drinks at the Ice Castle. Jake Kanoza and Nick Veason, who will be sophomores at Keystone Oaks this fall, admitted that making their hometown shadier wasn't the main reason they had volunteered.
"For the free pizza ..." Jake said.
"And doughnuts!" Nick added.garden
Kevin Kirkland: firstname.lastname@example.org or 412-263-1978.