When he starts kindergarten in two years, the young baby oaks we planted last week will still be shorter than he is. They’ll continue growing slowly, maybe a foot each year, so that they’ll finally be taller than he is by the time he gets his driver’s license, though still too skinny for him to carve his initials alongside another’s in a heart. By the time the oaks are sturdy and tall enough for me to sit and rest my back against, he may already have kids of his own. Perhaps I’ll bring them to visit the trees and gather up acorns to bring home and plant in their yard. Many, many years from now, when his grandchildren have grandchildren of their own, those trees that we helped to plant on Arbor Day of 2015 will finally stand tall and proud with gnarled limbs and massive canopies, roots anchored deep in the prairie. By then, no one will remember who planted the trees or know that we patted the soil beside each seedling, whispering words of encouragement, “Grow big little buddy.”
In a world of instant gratification, planting a tree is still an immensely satisfying experience. This past week, Great River Greening brought together nearly 200 volunteers to plant 3000 young oaks, grown from acorns, in the South Washington Conservation Corridor in Woodbury. Little by little, the South Washington Watershed District is restoring the land, set aside to provide food relief and infiltrate stormwater runoff from the city, to native prairie and oak savanna. Eventually the site will feature an interpretive center, as well as trails helping to connect Lake Elmo Park Reserve all the way down to the Mississippi River.
In spite of cold weather and light drizzle this Arbor Day, volunteers still turned out in mass for the tree planting event. We brought a small team from the Washington Conservation District, including my son Charlie – age three, and a co-worker’s daughter Linnea – age two. County Commissioners Lisa Weik and Karla Bigham spoke during the pre-planting ceremony, as did Watershed District managers Jack Lavold and Denny Hanna. Other volunteers included teams from local businesses, as well as area residents who signed up as families and individuals. Charlie and Linnea provided a distraction from the chilling rain, helping to tie little blue ribbons around the new seedlings and collecting earthworms along the way. By the time the oaks we planted begin to produce acorns, Charlie and Linnea will already be in their 30’s, with jobs and lives of their own.
Bur oaks are incredibly well adapted for life on the prairie. Though they grow slowly, their tap roots burrow down more than four feet within their first year, helping them to hold ground against similarly deep-rooted prairie plants. They can survive fires and even lightning. In fact, it is often impossible to tell how old a bur oak is by counting its rings because most of the older oaks have burnt and hollowed inner trunks from the repeated lightning strikes they’ve suffered.
American Forests calculates that a mature bur oak tree 60 feet tall and 105 feet wide with a circumference of 322 inches removes 19.56 lbs. of nitrogen, sulfur, ozone and particulate matter every year, and if planted in a built environment, can provide $3456.39 in stormwater control (by intercepting rainfall that would otherwise runoff into a storm sewer system). According to ecologist and author Doug Tallamy, they also support more than 500 species of larval insects, which in turn, provide food for song birds and other animals. They are slow growing, but long lived, reaching heights of 70-80 feet, on average, and sometimes living more than 400 years.
What will Woodbury look like when the young oaks we planted last week stand tall in groves upon the prairie? Who will pause to explore beneath them while out on a family picnic? What challenges will those future generations face and where will they plant their trees?