Slowly but surely, Lyme disease has reached near epidemic proportions in Pennsylvania. Twenty years ago, most of us never heard of Lyme disease. Now, most of us know someone who has had it and many of us have had it as well. Ticks not only are more abundant in Pennsylvania, but they also have migrated into Canada. It’s no coincidence that warmer winters have facilitated the spread of ticks to the North. Another noxious insect pest, the wooly adelgid, is decimating our state tree, the hemlock.
This species originated in southern Virginia but has steadily moved north as winters have warmed. As of 2007, the adelgid has impacted over 50 percent of the geographic range of the hemlock.
Hemlocks are what scientists call a “keystone species.” That is, one which many other species depend on for food, cover and nesting habitat. Brook trout, our state fish, is so closely allied with hemlocks that at one time they were called hemlock trout. Scientists predict that global warming will enable the adelgid to eventually eliminate our state tree from the eastern United States, thereby speeding the demise of our state fish.
Source: www.post-gazette.com
