Minnesota woodlands and climate change
How will climate change affect Minnesota woods? What changes should you expect? What can you do to prepare? This page will answer some of these questions.
Projected future changes
It’s hard enough to predict tomorrow’s weather. Predicting climate change is complex. Different climate models offer different predictions. According to a recent report from the Union of Concerned Scientists, by the end of this century Minnesota’s summer climate will resemble the current climate of Kansas, and the winter climate will be more like that of southern Wisconsin.
There’s general agreement that Minnesota’s climate will get warmer. What’s less certain is what will happen to precipitation: will it get warmer and drier or warmer and wetter?
Impacts on Minnesota forests
Minnesota lies at the juncture of four major ecological provinces, or biomes. Ecological boundaries depend heavily on temperature and rainfall patterns, and changes in temperature and rainfall are likely to have relatively major effects near the boundaries.
Warming temperatures are likely to stress trees that are adapted to cooler conditions. This stress may predispose trees to secondary insect or disease agents, making them more vulnerable. This would be exacerbated by longer and/or more frequent drought events.
Insects & disease
Healthy trees can defend themselves against most native insect and disease threats. However, stressed trees are more vulnerable. As a consequence, native pests like the two-lined chestnut borer and bronze birch borer can have more damaging outbreaks when trees are stressed. Both of these insects have had recent outbreaks due in part to drought events. These outbreaks, and associated losses, are likely to become more common.
Many invasive species, like buckthorn, can thrive under a wide variety of conditions. Some native tree species can only thrive under a relatively narrow range of conditions. Changing climate may displace some natives, creating growing space that will be filled by invasives.
Insects like gypsy moth (right) and emerald ash borer are likely to enter Minnesota soon. Different bugs have different impacts, but overall, new insect invaders will further stress and weaken forests, compounding stress from a changing climate.
What you can do to keep your woodland healthy
Here are a few general recommendations:
- Maintain diversity. Manage your woods to include a variety of different species. Different species will be affected differently, and some will be more resilient than others.
- Maintain stand vigor. Thinning your woods is an excellent way to improve overall stand vigor. Trees with large, full crowns receive more energy from the sun and are much more resilient than crowded, spindly trees.
- Grow and harvest more timber! Growing forests are carbon sinks, turning atmospheric carbon into wood.
- Monitor your woodlands carefully. Insect and disease outbreaks may travel through stands more quickly due to tree stress. The more quickly you can identify and act to control outbreaks, the more damage you can prevent.
- Do your part to reduce greenhouse gas emissions.