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Finding bear claw marks in the big
beech is an exciting adventure in our forests |
That's a jokey title, for a very un-funny problem that is moving into our forests.
This has been creeping ever eastward from the Maritimes, where it was introduced as an invasive species back about 1890... It doesn't move quickly, but it does move surely. And now it is here.
We speak of
Beech Scale, or Beech Bark Disease, or
Nectina coccinea var, faginata. Whatever name you care to call it, it is not good news. A few years ago, the Algonquin Park publication The Raven featured an article "Can the Park Stand without Elephant Legs?" Elephant legs... that is the familiar term for those huge, smooth barked gray beech trees that have graced our forests as long as we can remember. And it is a very good question, without any very good answers.
These beautiful trees provide a bounty of food for bears, deer, wild turkeys, squirrels, chipmunks. In fact, they are one of the primary and most important food sources for these species.
The disease is a one-two punch: The invasive and recently introduced beech scale insect (
Cryptococcus fagisuga) from Europe, coupled with a nectria fungus. While the nectria fungus was likely native to North America, the introduced scale insect provides an opening to a new host tree for the fungus. The disease begins with many scales feeding on beech tree sap while they form a covering of white wooly wax over their body.
Once the scales have opened wounds in the bark, the nectria fungus begins to colonize the bark, cambial layer, and sapwood of the tree. This stage of the disease produces cankers sometimes resulting in isolated tarry spots oozing from the bark and /or raised blisters and calluses on the outer bark covering much of the trunk. I am told by foresters that once you see the reddish or tarry evidence, the tree will be dead in a year. Gone.
Here's what you'll see on an infected tree --
Mature beech scales are a soft bodied, wingless insect, 0.5 – 1.0 mm long.
After feeding on the sap under the smooth beech bark, the scale is easily recognized by the covering of white wooly wax on their outer body.
In fall, the fungal fruiting bodies can be seen as deep-red, lemon-shaped structures in the bark.
Infection by the nectria fungus may also result in oozing from the bark.
Tree crowns appear yellow and die back
Can it be stopped? Well, yes. And no. If you have an ornamental tree and time and money, yes you can treat that individual tree. Can we treat the entire hardwood forest? No.
And why do I mention it now? Because this year it made its way to the Baysville area, with an outbreak near Ril Lake. And this week, we learned that there is an infected woodlot down the Port Cunnington Road, where I am told that the foresters have identified that 90% of the beech in the stand are affected.
And that means that it is here. Now.
Will all the beech trees die? No. The scale targets the mature trees, over 8" in stem apparently, which means that the smaller trees will hang on. They, however, do not produce the heavy harvests of beechnuts on which our wildlife relies. Beech trees are relatively slow growing. The glorious stands of enormous beech are the very stands that are at highest risk.
These are the big trees that can produce the abundant mast that feeds the bear in the autumn. But they don't start to really produce until they are thirty years of age... and with the beech scale, it becomes questionable if they will get that far.
There will be trees that are resistant. Like the elms... although we don't see many of them anymore gracing our forests or lawns with their huge outspread limbs. Or the ash, which are struggling with the emerald ash borer.
So we are watching our forest, and crossing our fingers, and hoping that we have enough beech that can resist this horrible new attacker.
Because the beech trees in our forests are one of our glories, and Lord knows, we are not prepared to say 'goodbye to all that.'
