The eastern hemlock has been dying in silence, being eaten alive by pests — but the Pennsylvania Department of Conservation and Natural Resources has developed a plan to intervene and save the state tree.
“The eastern hemlock is perhaps the most valuable tree in our state woodlands,” said DCNR Deputy Press Secretary Terry Brady. “[The Hemlock is] the oldest evergreen when you look at a forest, and perhaps the most valuable in terms of what it provides.”
The eastern hemlock was designated the official tree of Pennsylvania in 1931. It is a slow-growing, long-lived tree which can take 250-300 years to reach maturity and can live for 800 years or more.
The non-native, invasive hemlock woolly adelgid (HWA) is literally draining the life out of the eastern hemlock. These insects damage and kill the trees within a few years of first contact. The HWA is a fluid-feeding insect, which can easily be detected by its telltale egg sacs resembling cotton swabs that cling to the undersides of hemlock branches.
When in their native range, these populations of HWA cause little damage to the hemlock trees, but without natural enemies and possible tree resistance seen in their native range the presence of the pest poses a risk to not only the hemlock, but to the state’s natural eco-flow.
“All of our waterways pretty much depend on the hemlock in certain areas to keep the water shaded, cool, and clean,” said Brady, “[and with] that said thousands of trees are dying across the state, people realize when the look out, and see that the hemlock is gone.”
It serves as a shaded area for hunters—as well as protection for wildlife, especially white-tailed deer that use it for bedding in the winter. The bark of tree was once used to process leather.
So what is being done to protect the tree?
The DCNR’s plan is to first make an assessment of all the trees, and then begin to inject or spray those trees deemed salvageable. The plan also seeks to gather landowners input. Suggestions are also being solicited by the Bureau of Forestry at by Dec. 15.
Brady said education is key.
“What we can do is get the word out about this hemlock plan,” he said.
The plan, which provides information and guidance for both public and private land managers, is expected to help implement necessaries procedures. In addition to substantial background material, it also presents an eight-pronged conservation strategy, and critical research developed to aid in the preservation of the hemlock.
However Brady anticipates this will not be an easy fix.
“Landowners are going to have to come to grips with a cost, [deciding] is the tree worth saving, and if it is, it’s not an easy or cheap investment,” he said.
He also advises that seeking landscapers prior is an imperative step for landowners.
While the threat is eminent the winter chill may allow for both researches and landowners time to prepare. “Warmer climates are more conducive to the spread of the insect,” said Brady. “Last winter was bitter cold and it slowed the advancement.”
