Genetic Impacts of Forest Management Strategies on Sugar Maple in the Northern Forest

To examine how forest management practices affect genetic diversity of sugar maple, NSRC researchers will quantify the effect of two common management strategies (even-aged and uneven-aged) on northern hardwood stands with a strong sugar maple component. Managers use both practices to achieve a variety of objectives; however, no one has explored their impacts on tree genetic diversity. Researchers will measure differences in genetic diversity between stands treated with shelterwood (for even-aged) and selection (for uneven- aged) methods and no management within the last 100 years (as the control group) by examining three age classes (seedlings, saplings, and mature trees) per stand, with two replications in each of the four Northern Forest states.

Researchers will use sugar maple genetic markers that are subjected to natural selection and related to the fitness of individual trees. They will analyze 720 leaf samples across the Northern Forest to quantify metrics of genetic diversity within and between stands and states in relation to each tree age class under each management practice.

Findings will help refine management practices, such as identification of trees or stands that are genetically diverse and ideal for use as seed stocks for regeneration or restoration and of pollen sources for assisted pollination to genetically enrich future generations. Results will provide baseline information for the level of sugar maple diversity and serve as the start of a Forest Genetic Resource Monitoring program for the Northern Forest to detect potentially harmful changes to forest adaptability. Genetically-sound harvesting practice is central to sustainable management of forest resources, especially the “genetic resource” that allows population and species-level adaptations to change.

Download 2021 progress report (PDF)

Download 2022 progress report (PDF)