I've been geeking out on conifers lately. Ever since I got to see the Giant Sequoia in California, I've been more interested in the pines, spruces, cypresses, and hemlocks in Ohio. Nothing east of the Sierra Nevadas comes close to the height or volume of the Sequoias and Redwoods out west, but we do get some interesting trees here.
One of the taller trees in the eastern US is the Eastern Hemlock. The tallest specimens can grow up to 170 feet and have diameters up to 4 feet. Unfortunately, pretty much all of the world record hemlocks have sucumbed to the hemlock wooly adelgid.
The hemlock wooly adelgid is an aphid-like insect that was introduced accidentally from Asia that feeds almost exclusively on the eastern hemlock. When they infest a tree, they are able to kill it within a couple of years. The Smoky Mountains in Tennessee was home to the largest trees at one point but they have all died because of this insect. The hemlock wooly adelgid is moving north and threatens to wipe out the Eastern Hemlock. There have been attempts to stop them with a beetle that is a natural predator, but they cannot keep up with the adelgid.
These are beautful trees. Get out and enjoy them before they are gone forever!