The killing front - areas that are characterized by high populations of beech scale, severe nectria attacks, and heavy tree mortality. Recent data from plots in Vermont, New Hampshire, and Maine show that about 28 percent of the large beech had died, another 22 percent were dying, and many of the surviving trees were so severely injured that they offer little hope as a source of quality material. The wax was removed before the photograph was taken. Beginning in midsummer, the insects deposit pale yellow eggs on the bark in strings of four to eight, attached end to end. The eggs usually begin to hatch in late summer and continue hatching until early winter.
Some larvae remain under the females, which die after the eggs are deposited.
If a suitable location is found, the insect forces its tubular stylet into the bark and begins to feed. It then transforms into a second-stage nymph, without legs and covered with woollike wax. The insect overwinters in this stage and, in the spring, molts to become an adult female. The fungus - In North America, two species of the nectria fungi are associated with beech bark disease. The principal one, N. coccinea var.