Paths of infection

In a few more years, the path in this picture will be two centuries old. That’s fifty years older than any of the buildings in the hollow. They’re the healed remains of the roads the colliers built when they first clearcut the mountain, with results that must have been catastrophic for the hollow: floods, fire, massive loss of topsoil. But now, chances are if you come to visit in any other season than winter, our moss-covered trails are one of the things you’ll most remember about the place. They’re beautiful. In spring and summer, before the leaves fall and turn every step into a loud whisper, it’s possible to stalk through the forest as quietly as a burglar.

I always confuse the path with the destination. Don’t you? I start out intending to go somewhere, but then something catches my eye and I slow down for a closer look. Then I notice more. An hour hour later, I’ve only made it half a mile from the house.

Nothing draws the attention quite like someone or something with a disfiguring disease. Whatever is decimating the mountain laurel here begins with colorful eyespots: brown rimmed with red and yellow, like targets in reverse. With certain kinds of sickness, yes — the leading edge of infection is marked by unnatural brightness. That fever glow.

I found a black gum tree with a bad case of warts. Each wart is a hermit’s cell for an Eriophyid mite, a microscopic, two-legged relative of spiders. It goes through a mere two larval instars, and manages to have sex while maintaining its immaculate separation from others of its kind:

Mites do not mate with each other; sacs that the male leaves lying around on the leaf surface fertilize the female as she walks around.

Freedom from sexual contact can be liberating. Some species of Eriophyid mites alternate all-male generations with all-female generations. Very little is known about them beyond these basic facts. Some 90 percent of Eriophyidae have yet to be named and classified by taxonomists, so I suppose chances are good that this is one of them.

For the tree, the galls aren’t the sickness, they’re the treatment. The tree would say, with some justification, that each mite is walled in to keep it from spreading. But the mite, like thousands of other gall-making arthropods, is in fact practicing a kind of ju-jitsu, using the tree’s defenses against itself. The feeding chambers are not only ideal for solitary contemplation, if such be the bipedal mite’s inclination, but keep out most predators, as well.

After they attain adulthood, the Eriophyidae abandon their chambers. This is the time when accidental sex may occur. Many of them also take to the wind and float for miles, like the Daoist sages of legend. Some of them, no doubt, end up in my lungs.

This black gum bears the scars of somewhat larger animals — bears and humans. When I painted a trail blaze on it seven years ago, I can’t remember seeing the other marks there, but judging from the depth of scar tissue, bears have been carving up this tree for some time. Though they much prefer electric and telephone poles to communicate their “Kilroy was here”-type messages to other bears, any conspicuous tree, living or dead, will do. For hikers, this is a useful reminder that they aren’t the only ones using the trails. For bears, it is perhaps a gratifying reminder of the fact that our paint marks are no match for their claw marks. Bears often destroy human-made things left in the woods — it’s as if they regard us as some kind of enemy.

For the tree, unless and until the trunk is completely girdled, none of this is a real impediment to continued growth and prosperity. Black gum trees are masters at walling off wounds with thick scar tissue. They almost all rot out at an early age, making them impossible to date by ring counts. But the outer shell of a mature black gum is hard as iron.

White pines fight disease with tars, which can sometimes keep them standing after death for as long or longer than they stood as living trees. A century after the forest fire, a short-lived path that the flames took up the trunk of a pine tree is still marked with charcoal and a livid blaze.