Harrison sets deadline for removal of diseased Carlisle Street elms

Harrison officials have set an April 15 deadline for a Carlisle Street property owner to get two diseased elm trees cut down.

If the job isn't done by then, the township will hire a contractor to do it to protect other elms along the street that will become more vulnerable to infection as the region moves further into spring, said Lindsay Fraser, supervisor of the township's zoning and ordinance department.

The infected trees are on one property in the 1000 block of Carlisle Street.

Fraser would not identify the property or its owner, because it is an active ordinance enforcement case.

Fraser said the township was made aware in the fall that the two trees are afflicted with Dutch elm disease, a fungal disease of elm trees that is spread by elm bark beetles. Believed to be native to Asia, the disease has devastated elms in America and Europe that were not resistant to it since its accidental introduction.

The bark is falling off of the affected trees, Fraser said.

Carlisle Street is recognized for its elm trees.

As of September 2014, there were 189 American elm trees flanking the street — forming one of the largest such stands of elms in an urban area in the state, according to the Pennsylvania Department of Conservation and Natural Resources.

The Allegheny Shade Tree Association was formed in 1994 to protect them. It was the same year that Dutch elm disease was found in some of the street's trees, which were removed to prevent it from spreading.

Fraser said the township first gave notice to the property owner about removing the current diseased trees in November. The notice specified it was best that they be taken down during winter.

“The trees have still not been taken down,” she said. “It's important for the trees with Dutch elm disease to come down before they bud. The surrounding trees are more susceptible to Dutch elm disease at that time.”

If the trees, which reach more than 60 feet high, aren't down by April 15 the township will contract with someone to do the work and the property owner will be responsible for reimbursing the township for the cost plus penalties, Fraser said.

Brian C. Rittmeyer is a Tribune-Review staff writer. Reach him at 724-226-4701, brittmeyer@tribweb.com or on Twitter @BCRittmeyer.