Rooted in Research
On the Search for Success: Revisiting Group Selection in Promoting Northern Hardwood Forest Biodiversity
If you walk through a northern hardwood forest in the Lakes States region today, you'll likely experience something different than your ancestors would have centuries ago. Instead of a variety of species, including eastern hemlock (Tsuga canadensis), paper birch (Betula papyrifera), and eastern white pine (Pinus strobus) saplings, you'll likely see a proliferation of sugar maples (Acer saccharum), their iconic leaves soaking up the sunlight. According to Christel Kern, a research forester with the U.S. Department of Agriculture, Forest Service's Northern Research Station (NRS), "There has been growing concern about northern hardwood forests composed of sugar maple monocultures. One pest or pathogen could wipe out an entire stand." Recently Kern, along with Michigan Technological University professor Christopher Webster and master's student Samuel Knapp, revisited a long-term study site in Wisconsin's Chequamegon-Nicolet National Forest to further investigate cohort development and biodiversity.
For more information contact
Science Delivery Specialist
USDA Forest Service - Northern Research Station
Key Management Considerations
- Contrary to what was previously thought, group selection, a common tool in the management of uneven-aged stands, may not lead to increased tree species and natural regeneration.
- Additional site preparation beyond the current status quo, such as soil scarification, planting, and herbivore protection, may be needed to achieve biodiversity goals.
- A stand's composition 2 years post-harvest is a strong indicator of its future makeup. This discovery can serve as a highly useful tool for foresters wishing to determine the success or failure of stands early on, allowing them to adjust management practices accordingly.
- Advance regeneration may be vital for adequate stocking within large canopy openings. Targeting group-selection openings where shade-intolerant advance regeneration already exists can facilitate future overstory tree diversity.