Are you thinking about planting a tree—or 100? Trees not only add beauty to the world and provide habitat for wildlife, they also absorb carbon dioxide, reducing the threat of climate change.
One of the most important considerations when planting a tree is choosing the right tree for the location and for the site's specific conditions. A changing climate adds a new consideration. Think ahead and consider not only conditions today, but conditions to come in the future, says DNR silviculture program consultant Paul Dubuque.
As Minnesota's climate changes, it is expected to become more suitable for species like black cherry.
"Suitable habitat for trees will increase and decrease," Dubuque says. "Thus, some trees will likely be able to expand and occupy new sites where they are currently not present, and others will have difficulty adapting and may decline in abundance."
In general, DNR Forestry experts expect Minnesota's climate to become less suitable for aspen, paper birch, tamarack, and black spruce. On the other hand, it's projected to become more suitable for species such as American basswood, black cherry, northern red oak, bur oak, sugar maple, red maple, and eastern white pine.
Some of these trees may be right for your planting plans, but first ask yourself what your goals are. If you're planting for a larger area, do you seek habitat, beauty, timber income? Keep in mind the value of diversity. Include a variety of trees of a variety of ages to help ensure the woodland has elements that can withstand whatever the future brings. Remember that the interaction among tree species matters, too. If you're planting a yard tree, is your goal shade, beauty, shelter from wind, attracting wildlife? Would a tree that keeps its foliage all winter or one that loses its leaves be best to meet those goals? Would a tall, skinny tree or a fat, short one best fit your space?
Next to consider are local conditions: drainage, amount of sun, temperatures, rainfall, and so on. This is where our changing climate comes in. Simply put, local conditions aren't what they used to be. Average minimum and maximum temperatures and precipitation have all increased in Minnesota over the past century, and rain and snow patterns have shifted. And change continues: Over the lifetime of a tree planted today, meteorologists tell us that the number of frost-free days and the number of days with temperatures above 95 will increase; heat waves and storms will become more severe; and drought will become more of a problem.
In addition, climate change is expected to worsen the threat of wildfires, insect and disease outbreaks, and invasive species. In fact, DNR Forestry has called climate change "the most significant threat to Minnesota's forests over the next century."
For planting a tree in your yard, DNR forest ecologist John Almendinger suggests you check out the USDA plant hardiness zone map and choose species appropriate for your zone or the one to the south of your zone. If you are planning a larger landscape restoration, consider consulting a forester for help in deciding what to plant where and how to manage your forest as it grows.
Climate considerations shouldn't outweigh the basic rules for choosing the right tree for the right place, says Valerie McClannahan, DNR senior planner in urban and community forestry.
"If you have electrical lines overhead, you will want to plant a smaller tree. If the spot floods a lot, plant a tree that does better in moister conditions," McClannahan says. The process, she explains, means "really looking at the space itself and saying, 'What will go well right here?' You could plant a tree that would be fine climatewise for 20 to 50 years, but if it's in the wrong place you're going to have to remove it sooner rather than later anyway."
Landowners and homeowners alike are encouraged to take advantage of DNR Forestry resources for choosing tree species and planting trees. Most important of all? Don't let uncertainty get in the way of action. Gather information, make a decision, and plant those trees. The future will thank you.
Mary Hoff, freelance writer