This is the time of year for sharing, when families and friends gather for meals, gift-giving and rituals. It’s a reminder of how much we mean to each other and how much we need each other.
Nature, too, is all about sharing. A big tree standing by itself may look majestic and self-reliant. Yet a tree is never alone. Like all living things, it belongs to a community of organisms that depend on each other. “That’s what an ecosystem is — the way things live together in a particular place,” says Julie Janoski, manager of the Plant Clinic at the Morton Arboretum in Lisle. “Every plant, and every other living thing, evolved to have a place in a community.”
The giant redwood trees of California are among the largest organisms in the world. Yet to live, they need help from some of the smallest — billions of tiny bacteria in the soil that provide the trees’ roots with nutrients. Squirrels and beetles help redwoods distribute their seeds. In return, these and many other animals receive food and shelter. The moist canopy of the redwoods creates growing conditions for so many other plants, lichens and other organisms that it’s been called “a garden in the sky.”
In the native woods of Illinois, oak trees stand at the center of many natural communities. They provide food, shelter and nest sites for hundreds of species of animals, while spring-blooming wildflowers and other native plants thrive at their feet. That’s just above the ground: In the soil under an oak are thousands of species of bacteria, fungi and invertebrate animals.
Oaks, like many trees, have especially intimate relationships with particular kinds of fungi that live on their roots. The fungi send out filaments that probe far into the soil, bringing back important nutrients to a tree’s roots. In return, the tree shares the energy-rich sugars it produces in its green leaves. “It’s like a gift exchange every day,” Janoski said.
Often, trees and other plants live in groups like families. After all, acorns tend not to fall far from the tree, although they may get some help from squirrels and birds that move them a little farther. “When you see a grove of oaks or a cluster of pussy willows, chances are they’re related,” Janoski said.
As we share food, music and memories with our families and friends, let’s not forget the natural communities just outside. In our yards, along our streets and in our forest preserves and national parks, plants and animals need space and care to keep living together.
Just as we nurture our relationships with yearly rituals, let’s protect nature so trees, wildflowers, chipmunks, caterpillars, birds and, yes, bacteria can share our world.
For tree and plant advice, contact the Arboretum’s Plant Clinic (630-719-2424 or email@example.com).
Beth Botts is a staff writer at the Morton Arboretum in Lisle (www.mortonarb.org).