Life of a dead tree

Last night Joshua asked me about some curious growths he had seen on a log at our trailhead. Fairly sure I knew which things he meant, I told him it was some kind of fungus. He said that he had opened one and it had a small grub inside. This piqued my curiosity because it sounded as though maybe the rough, dry spheres were actually insect galls. Even though I was ready for bed, I asked him to go show me. I wanted to be sure we were talking about the same thing.

Our dog, Sadie, at the trailhead last October

Our trailhead marks the starting point of a short trail loop through our small hollow. The trail goes back into the hollow following the typically dry streambed at the bottom of the valley and then goes up a steep hill on the western ridge and follows the ridge back northward to the starting point. The trailhead is at the corner of our side yard and is marked with a grouping of several cut logs standing on end like a cluster of stumps.

Joshua and I grabbed flashlights and walked out to the trailhead in the dark. When we got there, our light revealed a very busy place. Although I had noticed a few fungi beginning to grow on the logs, this is a spot that normally gets little attention. The logs merely form a decorative yet rustic entry into the woods. Under closer inspection it was clear that there is much more going on here.

The first thing we noticed was a harvestman (aka, daddy longlegs) that seemed to be eating the remnants of the sphere Joshua had opened earlier. Whatever the grub was doing there, we decided the sphere had to be some type of fungi. Our light revealed a few ants scurrying about also, no doubt also picking up a meal wherever they could. There were also beetles, more harvestmen, a millipede, a snail, and centipede, all busily going about their business.

There are no fewer than a half dozen species of fungi on the logs: the curious, roundish gray-brown lumps Joshua had asked about; small shelf-fungi; a yellow, jelly-looking mess commonly called witches butter; small little nondescript stalked mushroooms; and more than a couple random fairly shapeless scaly white fungi growing across the surface. A good teacher could have an entire mycology class field trip right here at the trailhead.

Moss is also beginning to grow on the sides of the logs now. I expect this to continue more and more as the fungi break down the wood, offering more fertile "soil" for the moss. It's amazing how different these logs are from when I rolled them into place and sat them on end a year ago. At the time, they were little more than large cylinders of wood, but now they seem full of life, full of promise, even as they decompose.

I understand from people who study such things that the biomass of a log on the forest floor is actually several times higher than the biomass ever attained by the living tree. The living portion of a tree is pretty much limited to the leaves and an outer ring of tissue in the woody portions. The live part of a tree trunk is a long, tall cylinder supported by no-longer-living wood within. Once the bole of a tree falls to the ground, the dead wood immediately becomes both structure and nutrition for a myriad of other life-forms for years to come. In a very real sense, a dead tree is more alive than the living tree ever was.