May 28, 2016: Beech Bark Disease: what are we going to do about it?

It’s been 125 years coming, but Beech Bark Scale Disease is here. It was accidentally introduced at Halifax, NS, in 1890, on some European beeches sent over by Queen Victoria. It is a two-stage disease, the first being the introduced scale insects. Though tiny, they proliferate over the bark of a tree, visible as a scurfy white waxy covering. When the feeding activities of the scales have opened thousands of tiny wounds, fungi invade and kill patches of bark. The lovely, smooth trunks become disfigured. The wood underneath rots and most trees die.

In our Study Area, we have found them on only a few American Beech trees along Trail 25, west of parking lot P6. But feeding scales give rise to crawlers, and they may be expected to spread in the same manner as Brown Scale.

The scales cannot be stopped, and most advice is to cut down the trees. But they can be studied, and we discussed how we might map them, as we have done with Hemlocks and Butternuts. And we can try to learn the details of the insects’ life cycle. While Rob was talking about these things, Morgan was busy drawing. She produced a composite image from his slides of a diseased tree he had photographed in the Maritimes, and the rich, coppery coloured autumn foliage of one here at home.