A tree has fallen on your property. What should you do? From a conservationist’s standpoint, the best course of action is often to leave the wood where it lies. Ecosystem health depends upon the nutrients provided by decaying plant matter, and downed trees are a major boost for the bottom of the food chain. Their great storehouse of carbon sustains a host of mycorrhizal fungi, bacteria, and other microscopic life forms that break down the molecular structures of organic matter and convert them back into the building blocks of life. That is why dead trees make great nurseries for other plants, including replacement trees. Take a look at the Late fall oyster mushrooms pictured here – they fed beetles, deer, and my own family for weeks.
How long does it take for a dead tree to rot? Generally 70-150 years, depending upon the species, the size, and the climate. Hardwoods like maple and oak actually rot faster than softwoods like spruce and pine, and both degrade faster with moisture. It might be said that the true life of a tree is measured in living years (50-150 on average) plus 30 years as a standing snag, and another 70 years or so on the ground.
If this seems like a long time to wait, consider that in the meantime, the limbs from downed trees provide habitat to plants and animals that require cover on the forest floor, like wrens and chipmunks. Salamanders, toads, and many mammals make burrows under logs, or live inside. It may be possible to work these features into your landscaping scheme, or to obscure them with a native climbing vine like Virginia creeper.
Where it is unfeasible to leave downed wood on the ground, you might stick with a living lighter on the land approach and move it in large pieces to rot in a natural and out-of-the-way location. Smaller pieces will rot more quickly but require more time and energy to cut. Do not stack unless you seek to preserve the wood for burning or other use. Occasionally, treefall in wind storms is so catastrophic that the survival of nearby trees and understory is threatened. Pictured here is some of the damage wrought by Superstorm Sandy upon the forest in Carolin’s Grove Preserve in Pound Ridge, NY in 2012.
When so many trees are lost from the canopy in such a short time, there is great potential for lasting ecological changes including species loss, soil loss, and decline in water quality. Our stewardship crew recognized that natural forest regeneration at this site was additionally threatened by excessive deer browse and the invasion of non-native species, and we decided to take action. We hired a trained crew to spend several days cutting and chipping dead spruce in the Preserve, with a special focus on removing dangerous hanging limbs. Then, we installed a series of fenced areas in the new clearing and planted those with an assortment of native tree and shrub saplings. This year, we plan to add more trees and pollinator plants. We are already seeing the signs of natural forest regeneration.
When a tree falls in the forest, or even in your yard, it pays to think long-term about what course to take. To learn how to select and plant native tree species on your property, attend our free workshop on May 7, 2016 (more information here) or volunteer with us on a tree-planting project in Pound Ridge this Spring!