The climate is changing. Data presented in numerous scientific papers have quantified the changes many of us have observed anecdotally.

For instance, satellite and water sensor data in a 2024 paper in the journal “Environmental Research” (v.19, p.1-11) suggested that different areas of the Great Lakes region have experienced less winter weather over the last couple of decades. From 1996 to 2023, the number of days with ice cover on some Great Lakes inland bays had decreased, including those of Lake Huron. Across the Great Lakes sample area, three fewer days of ice cover occurred every two years. Fall weather is being extended in some areas and spring weather is coming sooner in other locations.

Different seasons offer opportunities or limitations for different forest ecosystem types and their management. What are some of the pros and cons of a changing climate?

During winter months, especially when cold weather sticks around for weeks or months at a time, areas with wetter soils can freeze solidly. Under these conditions, heavy logging equipment can access areas without causing rutting (deep tracks in the soil) and making timber inaccessible during other seasons. Swamps dominated by conifers such as tamarack (larch), eastern white-cedar, black spruce, and balsam fir or deciduous tree species such as balsam poplar (“bam”), red maple, and (formerly) black ash are often harvested during the winter.

However, changes in the duration and severity of winters may reduce the opportunities for these operations in the future. Planning, especially that lock landowners into formal agreements, should take this into account and be more cautious in scheduling winter harvesting activities. In many instances, landowners may wish to avoid the complications of future winter harvesting and treat swamps as “set asides” or refugia for biodiversity.

Cold winters may also keep some invasive organisms at bay or slow their spread. A paper in “iForest” (v.17, p.295) outlines the potential impacts a warming climate may have on different forest insects and their tree hosts. Species such as the gypsy (spongy) moth may have better conditions for population growth under warming winter scenarios, for instance. Other species, such as hemlock woolly adelgid, may expand their range with a warming climate.

Changes to our climate can also provide opportunities for forest landowners. For instance, while many landowners plant tree and shrub seedlings during the spring, summer droughts can lead to planting failures.

Woody plants spend a significant amount of their energy growing roots when young. Roots not only provide stability for the growing plant but are involved in water and nutrient exchange with the surrounding soils. In some cases, fungi (mycorrhizae) assist the plant with these exchanges.

An extended fall may provide opportunities for more successful planting efforts. Fall rains, followed by winter snows, and subsequent spring rains provide a series of potentially wetter environmental conditions that may benefit seedling root development and better prepare the plant overall for drier summer months.

Change is all around us. A naturally complex forest may allow for more resistance and resilience for forests and their biodiversity to adapt to the uncertainty of climate change. For many forest types, evidence-based guidelines for managing forest complexity exist. Forest landowners, and the foresters and wildlife biologists they work with, may be well served to learn more about this growing body of knowledge and plan and manage accordingly.

Greg Corace is the forest and wildlife ecologist for the Alpena-Montmorency Conservation District. For more information, including assistance with the Qualified Forest Program and related forest planning and management, email Greg: greg.corace@macd.org.