On an eight-mile stretch of Route 271, between Johnstown and Mundys Corner, nearly 100 dead evergreen trees are visible from the road.
They’re easy to spot, as these are not your average Christmas trees. They are huge, standing 30 or 40 feet tall.
The same story is in evidence across the region. Giant evergreens, many once a part of a proud homeowner’s landscaping, stand with most or all of their needles gone. A few have been cut down, but many remain standing – skeletons of what they once were.
So, what’s killing the trees?
Scott Sjolander, a Penn State Extension educator who focuses on urban forestry in northwestern Pennsylvania, says there is probably more than one cause, pointing out that recent sewer and gas line work could be blamed in some instances.
“That has had a heck of an impact,” he says. “Big root systems get impacted.”
Disease, insects, climate change and old age also could be to blame.
“Colorado blue spruce, after they reach about 40 years old, are not really happy here in our environment,” Sjolander says.
“Fungi and the environment catch up with them.
“It really is kind of old age, because they can no longer fight against fungi, like cytospora canker.”
The disease is rarely seen on trees that are younger than 20 years old.
‘Very wet weather’
Sandy Feather, a Penn State Extension educator stationed in Pittsburgh, says the region is seeing a lot of issues with spruce trees, especially the Colorado spruce.
“They are susceptible to a number of needle cast diseases and a canker disease that kills branches, usually from the bottom of the tree up,” Feather said.
“While we have grown them successfully for decades, western Pennsylvania’s climate and soils are very different than Colorado’s.
“It seems that mature trees are especially in decline, but I have seen young trees defoliated by rhizosphaera needle cast. (We had) very wet weather last year and much of this seems to make these diseases worse.”
Brian Wolyniak, Ph.D., an extension educator for urban and community forestry with Penn State Extension in Pittsburgh, agrees that weather has probably had an impact on area trees.
“In terms of blue spruce, (we’re) primarily seeing a good amount of rhizosphaera needle cast, likely made worse by above average precipitation the past couple of years,” he says.
Bob Jordan, of Johnstown’s Jordan Tree Service, also believes the weather is impacting trees.
“We had an overabundance of rain last year and I think the ground saturation killed a lot of them,” Jordan said.
Insects and climate
Bark beetles also pose a threat and climate change may be a factor as higher temperatures favor winter beetle survival.
“Bark beetles always carry fungi with them,” Sjolander said. “They break down the tree’s vascular system.
“Trees planted too closely to each other crowd themselves out and then pests will occur. Often they will not get enough light and that will drive down their resistance.”
Feather said she could not definitively say what is killing the trees in this area without first examining them, but added that the Douglas fir is another tree that is in trouble.
“They are susceptible to two needle cast diseases – sometimes the only foliage left on them is the current season’s growth,” Feather said. “While the diseases can be controlled with fungicide applications, that is not a sustainable situation in most people’s landscapes.
“As a matter of fact, they may not be grown as Christmas trees much longer because growers have to make so many fungicide applications to keep the needles on them that they cannot charge enough for the trees to cover the costs of constant spraying; it is not sustainable.”
Jordan also is concerned about Pennsylvania’s state tree, the eastern hemlock.
“They are being killed by hemlock wooly adelgid,” he says.
Although dormant right now, the hemlock woolly adelgid appears as tiny white balls of cotton, attached where the stem meets the base of the hemlock’s short needles. First found in the eastern United States around 1950, the disease has destroyed hemlock trees in areas such as the southern Appalachians and the Great Smoky Mountains. Once infested, a tree might only live a few years.
Wolyniak says homeowners need to make good decisions when planting decorative trees.
“What we can take away from the decline of these trees is to be thoughtful when choosing trees and other plants for the landscape,” he said. “Select species that are native or more adapted to our local climate as that may help reduce the potential for pest and disease issues over time.”