A Solitary Walker: Rich woods, handsome plants and forest succession

The two little brown dogs and I crossed over our river, the West Branch of the Ompompanoosuc, a couple of weeks ago for a hike up into the rich woods nearby. We headed uphill to the fir swamp where my favorite liverwort— handsome woolywort grows.

How could one not love a fuzzy ancient bryophyte with a name like handsome woolywort? Trichocolea tomentella is very particular, growing only in mineral-rich woodlands with groundwater flow, not too acidic nor too limey. In fact, this is the only place I have ever found it around Strafford.

As we hiked up the trail sniffing for the woolywort, the dogs’ brown legs turning black, and my boots sucking into the muck, we stopped short, as a half dozen large fir trees had blown down — trunks and root balls fallen like pick-up sticks across the path. It is common for shallow-rooted trees to go tumbling in a strong wind in wet soils like this. The hollow they leave behind and the root ball they take with are referred to as pit and mound or cradle and pillow. Years after a big blowdown, you will see little hills where the root balls had been, with young birch trees, who like to be up above the competition, growing. Various tree seedlings will grow on the downed trees, called nursery trees, because they nurture, through their own decomposition, a straight line of saplings.

The dogs and I picked our way through the sphagnum and fallen fir branches, and I thought about disturbances, how ecological shake-ups like these are beneficial to biodiversity. When things change in the forest, species take advantage of the new niches. Mosses and ferns will grow in these hollows and on the rotting logs, and winter wrens may nest under these root balls.

The concept of a stable, unchanging mature healthy forest has been replaced by one of constant succession. Bare rock left behind after a major disturbance like glaciers, will be covered with lichens and moss, which over time, will become shrubs, then small trees, then larger trees, then even larger trees until a blowdown, or crown fire, or lava flow (if you’re near a volcano), or massive overgrazing returns the land to an earlier stage of succession. Look around the hills of Vermont at the large swatches of white pine trees growing where sheep once grazed. Come back in 100 years, and those patches may be hardwood forests, unless we have another period of sheep fever, or even worse, urbanization. Foresters will sometimes clear-cut patches in a deep forest to let in sunshine and create a better habitat for caterpillars and the birds who eat them.

The dogs and I continued our hike up into a dryer hardwood forest where the spring beauties and sharp-lobed hepaticas covered the forest floor, and a little higher up where the delicate fern-like leaves of squirrel corn and Dutchman’s breeches grew. Stopping to take in the endless green of wild ramps below, a red fox darted through, escaping our intrusion. A ruffed grouse exploded from her nest, flying off like an overloaded cargo plane.

When we got home, I emailed the landowners and showed them pictures of the balsam firs. I hoped to convince them that this blowdown had just created a new habitat for winter wrens, and for hundreds of mosses, ferns, fungi, and other animals who benefit from complexity, rather than as a dangerous mess that needed cleaning up.

The very next week was sunny and warm, with spring on the way, and the dogs and I returned to the swamp, where we heard not only winter wrens warbling up and down and on and on, but also brown creepers, who nest under the peeled bark of messy old trees. Ruby-crowned kinglets were migrating through, and the wood thrush played his flute. The elusive handsome woolywort was hiding, but I promised to keep looking while keeping company with two little brown dogs and the songs of wild birds.

Micki Colbeck is a naturalist and writer and chair of the Strafford Conservation Commission. Write to her at mjcolbeck@gmail.com.