The Hemlock forest on the shore of Long Island Sound in Guilford CT’s Westwoods was a trademark of the landscape just over a decade ago. It littered the dark forest floor with soft pine boughs and needles, providing a safe place for many plants and animals. When I first started biking in Westwoods in 1988, it was much more daunting than it is now. You could not see landscape and trail through the woods. It was richer and darker. The forest was so dense it would get dark an hour sooner than the outskirts. It was soft dense and quiet, well insulated and felt distant from the outside world. Today my mountain bike rides are rockier and the woods is more eroded and open. It almost reminds me of J.R.R Tolkiens description of Mordor. Many additional species of trees are dying, while the soft dark  hemlock forest's domination is a memory.

“The disappearance of the Eastern hemlock could potentially induce severe ecological changes, particularly along the state's watersheds, where the tree is most plentiful, said Dr. McClure. Many of those areas could be exposed to erosion, and some river ecosystems may be vulnerable to severe disruptions. Without the shade of the hemlock, he said, the temperature of rivers and streams would rise, possibly affecting trout and other fish that need cooler water to breed. The loss of the tree as a habitat for flora, fauna and wildlife would also alter the character of several Connecticut forests. The Eastern hemlock, native to Connecticut, is among the state's most abundant conifers and accounts for around 10 percent of all its trees. It grows to a height of 60 to 70 feet, with a diameter of 2 to 3 feet, and can live up to 600 years. Hemlocks thrive in cooler, wetter environments along steep, north-facing slopes with rocky undersoils. The tree is unrelated to the herb of the same name that killed Socrates. The early European settlers in Connecticut made tea from the leaves of the hemlock tree and used its needles as an ingredient in root beer. The bark was also used as a commercial source of tannin to produce leather. Today the evergreen is a popular ornamental for use as a shade tree and hedge.

In the wild, hemlocks serve as a habitat for a variety of mosses, lichens, mushrooms, slime molds and shelf funguses. Animals, like the white-tailed deer, feed on its foliage and use the hemlock stands as a barrier against winter winds.

The adelgid kills the hemlock by piercing the branches and sucking the sap from the tree. During the feeding process the insect injects a toxic saliva, causing a physiological New oil sprays are proving effective against backyard insect pests. Gardening, page 19. change in the tree, subsequently restricting its ability to absorb nutrients. After an attack by the insect, the hemlock usually dies within four years.

Although the amber-colored adelgid is visible to the naked eye, its presence is most conspicuous by its chains of white egg sacks that resemble the tips of cotton swabs. The insect, discovered in Virginia 30 years ago, has advanced at a rate of about 30 miles a year and has spread throughout southern New England to New Hampshire and west to Pennsylvania, New Jersey and New York.

Woolly adelgids produce two generations each year. When the eggs hatch in April, the insects find their way to the branches and begin feeding. At the end of June a new generation is produced and goes into dormancy until late October, then feeds from November through March.

For the past decade hemlocks in several areas like Westwoods have also been host to the elongated scale, another piercing insect that attacks the tree's needles, Dr. McClure said. Though it is not as aggressive and relentless as the adelgid, he said, "together, the two insects pack quite a potent punch."

Dr. McClure said he believed that the adelgid was native to Japan, where it occurs on the Japanese hemlock but does not do any damage. In the Pacific Northwest adelgids have adopted the Western hemlock as a host, but the tree has also proven resistant to the insect. Experiments by Dr. McClure have shown that even when the Western species of hemlock is transplanted in Connecticut and artificially infested with the adelgid, the tree maintains its resistance. Why the Eastern hemlock is unable to withstand the insect's assault remains a mystery, he said.” - NY Times 1992 09/29.