A Matter of Scale—

A.V. Walters—

Beautiful? Yes. But look closely at the bumps on the twigs.

Rick and I have returned to our Sundays “day off,” in which we spend Sunday afternoons cutting wood up in the woods. We are still clearing trails and cleaning up after the wild Storm of 2015. I’m sure that the trees down, from just that storm, will heat our Michigan winters for several years to come. This doesn’t even touch the backlog of deadfall accumulating from the dying ash and beech trees. We’ll have work, and heat, for the rest of our lives.

Last Sunday I noticed that the forest was sticky. All over, the understory plants are glazed with a tinge of sap—not unheard of in spring, but a little unusual, given how dry it has been. After a light snow year, April and May had precious little rain for us. The forest is crispy-dry. We didn’t get any of our usual spring morel mushrooms. Here, and up in the U.P., there have been fire warnings. (In May!) We watched the Canadian wildfire in Fort McMurray in horror.

This is not really unusual—when California has an El Nino season, Michigan’s weather is mild and dry. Finally, this week the dry spell broke and we’ve seen lovely storms to accompany the greening of our forests.

So what’s up with sticky? Yesterday, a friend, brow furrowed with concern, pointed out the scale on the maple tree next to our house. Yuck. His trees have it, too. Scale is an insect infestation. Maples always have some measure of scale, but the outer branches of our tree were lined with the limpet-like outer shells of these tiny sap-sucking vultures. It appears that we are having a major infestation of scale. The scale is responsible for the sugar-coated forest.

We live in Michigan. Bugs, in all shapes and forms, are a way of life here. Still, bugs of any kind, in great numbers, are unnerving. After our friend left, I stood in the soft rain, running my hands down every branch I could reach, squishing all those thousands of little scale bugs. Rick just shook his head.

“What are you going to do, molest every tree in the forest?”

Well, no. But the two maples next to my house—those I can help. It’s worrisome. Is this, yet another forest calamity in our future? Naturally this called for a research trip to the internet.

The likely problem is the dry spring. Maple trees under stress produce a thinner, more sugary sap. It’s a stress reaction, to ensure the energy needed leafing out in spring. The scale bugs, in turn, thrive on the sweeter mixture, ironically putting the trees under more stress. So, as long as the dry cycle is not repeated too much over the years, the scale is a cyclical problem that will solve itself.

There are measures I can take. I could have “power washed” the trees, before the leaves came out. I could use poisons (not likely!), sprays or root saturation with systemics. I could use a dormant spray in the very early spring—a perfectly acceptable organic measure—like we’ll be using on the orchard trees when they’re bigger. But, Rick is right. I cannot treat the entire forest. I need to relax here, and wait patiently for the ladybugs. Scale is a favorite of ladybugs and birds.

In the meantime, the rains will wash the forest clean of “sticky.” And, at the same time, they will feed the trees, making them stronger and better equipped to deal with the pests. I’ll step back and let the problem solve itself. Sometimes there is a danger of looking too closely.