My intent with this series of blog posts, is to give you information that will help you create “soft landings” under your native Michigan trees. However, instead of jumping right into what soft landings are and how you can create and modify them to help support many organisms, I’d like to give you some background and a little of the story of my own experiences and learning. Feel free to skip to the blog post titled Soft Landings Part II and Soft Landings Part III if you want an abbreviated version.
Many people enter the world of native plant gardening because they love birds, butterflies, or other wildlife. My oldest son became interested in birds at the age of 12. Our family decided to join the local bird organization and we attended meetings regularly.
While learning about birds, we couldn’t help but begin to understand what birds need for survival: water, food, safety, and nesting areas are all important. Each species has different requirements. Necessary food items, for example, include berries for cedar waxwings and thrushes, seeds for goldfinches and ground feeders like sparrows, insects for nesting birds and the list goes on. We began to learn about the native plants, including trees and shrubs that would support a greater variety of species that we could watch in our own yard!
The more information you digest, the more you understand the interconnectedness of living organisms. The scientific term that encompasses this connectivity between living things and their physical environment is ecology. Ecology as a concept can be tracked back to Aristotle, but ecological study is a fairly new branch of biological science. It became more prominent in the 20th century as we began to see other species become threatened, endangered, and extinct due to human activities. It encompasses the study of interaction between organisms and between organisms and their physical environment such as soil, water, rock, etc. It also includes the ethics of how humans interact with these systems (ecosystems).
A recent example of the importance of intact ecosystems came out of observations and study at Yellowstone National Park. In the 20th century, wolves were driven almost to extinction in the United States due to human activity, with the federal government driving much of the killing. In Yellowstone National Park, wolves were extirpated (extinct within the park) by 1926. This caused an unforeseen cascading effect throughout the park. Wolves are predators of elk in the park. With no wolves to control the elk, the elk population exploded. This led to more feeding on young trees like aspen and willows. Willows are important shrubs for stabilizing rivers and streams. Without this stabilization, these water bodies widened, causing erosion. Birds that nested in the willows disappeared. And without the nearby wood source for beavers to build their dams, beavers faded away as well. When beavers create dams, they create pond and lake ecosystems (wetlands) with a shallow water setting that benefits many species. The loss of the ecosystem meant the loss of those species.
Observers of this destructive process began to realize that wolves and beavers are keystone species. Without these two important species, the ecosystem falls apart and many other species are lost. The reintroduction of wolves in 1995 has caused a tremendous turn-around by reducing the elk population and allowing the beaver to return and do their important work of engineering wetlands. Believe it or not, this concept applies to as small a parcel of land as an urban, suburban, or rural yard.
While your focus might be initially on just a few species of birds or butterflies that you’d like to attract to your yard by planting certain herbaceous plants or shrubs, you may begin to learn about the huge loss of insect life that has happened in the past several decades. You may have encountered Douglas Tallamy and his important work on identifying the number of insects that use our North American native trees. In particular, you may have heard that oaks are a keystone species, just like the wolves and beavers above.
Let’s put a bookmark here and cover how oak trees function as a keystone species, as well as learning about some of the organisms that use oak trees in the next post.