Eastern Hemlocks, evergreen giants capable of reaching 160 feet tall, once thrived from the Carolinas north to Canada. But a tiny asexual creature has wreaked havoc on the hemlocks, including the forests of the Great Smoky Mountains National Park. And it was found in Seneca Park last month.

Adelgids are small insects no bigger than aphids. They're typically reddish-brown to black in color, and less than 1/16th of an inch long. Their defining feature is a shield of white wool-like hairs. Hemlocks are the adelgids' favorite food, and an infested tree looks as if it has been flocked in a waxy white. They have no natural predators and one critter produces more than 90,000 eggs.

"They are primarily an Eastern Seaboard pest," says Liz Berkeley, a diagnostic lab technician with Cornell University Cooperative Extension. "They can do an amazing amount of damage. Ultimately, they kill the tree."

Hemlocks are indigenous to North America and structurally, they are a picture of power and grace. From trunks that can reach six feet in circumference, tourmaline blue-green branches flow downward in feathery formations. And more than two dozen bird species depend on hemlocks for cover and nesting, studies have shown.

Treatments do exist to get rid of the adelgids.

 "There are horticultural oil sprays and pesticides that can be spread on the soil," Berkeley says.

But large, older trees are difficult to treat.

This is the second time adelgids have appeared in Monroe County. The first was in 1999. For more information, call the Cooperative Extension's Garden Helpline: 473-5335.