This Week: Shelterwood Management

The photo above was taken immediately following the end of a timber harvest. So, you may wonder, why are all those trees still standing?

Finch Paper’s goal is to keep forests forested, healthy and growing by utilizing certified sustainable forest management techniques.  This management also provides important income to the forest owner for payment of property taxes; provides renewable wood products (tables, chairs, paper, etc.) for society so that we can have the quality life style we desire; protects biodiversity; and provides clean air and water.  Through management, the forest becomes more valuable to the owner and society as a forest and is protected from development.

Our foresters use several techniques that mimic the way Mother Nature regenerates forests here in the northeast, typically in life-cycles of 80-150 years. We do not plant trees, but instead help to spur natural regeneration. We also do not use pesticides or fertilizers in the forests we manage, allowing the soil, rain and sunlight to spur growth. We consider the trees grown here, in our own backyard, truly organic.

The predominant system of forest management we use is an even-aged technique called a Shelterwood system. Even-aged means that the trees in a stand are all approximately the same age (typically no more than 20 years difference between the oldest and youngest trees). Shelterwood means that the largest, healthiest trees in a forest stand are last to be harvested, so that they can provide seeds and shelter for the next generation of forest.  This is very important as the strongest, most well-adapted trees are the ones Mother Nature would save in her natural “survival of the fittest” selection process!

Let’s take a look at an 80-year forest rotation:

When the oldest trees in a particular area of the forest are approximately 40 years old, we typically “thin” the forest by removing the poorest quality trees and giving the remaining trees more room to grow, just as Mother Nature would. The trees removed would otherwise become stagnant and die as a result of competition from the healthier trees.  By harvesting them, we’re able to provide products of value to society before the wood decays.

The thinning process is repeated every 10 years or so, always removing the weakest, poorest quality trees.

Approximately 30 years after the first thinning, harvesters remove most of the remaining trees, leaving only the most “fit” trees — what we call “Seed Trees” — to provide the seeds for the next generation of forest. The open spaces created in the forest canopy by the removal of the weaker trees, allow more moisture and sun to enter the forest and help the seeds take root.  To summarize: thinnings make use of trees that lose the competition for survival with other trees,  while the “seed tree” cut mimics the effect an ice storm or a wind storm would have on a mature forest — removing many but not all of the trees.

Finally,  7 to 15 years after the “seed tree” cut, harvesters return to the stand and remove the seed trees, completing the rotation and allowing the new forest to thrive. The thinning process will begin all over again in 30-40 years.

I’ll discuss other sustainable forest management techniques in the weeks to come. As always, if you have any questions about forest management, please contact us.

Tags: Harvesting, Sustainable Practices