“There’s simply no way we can conserve the biodiversity needed to sustain ourselves and all life on Earth if we ignore urban areas,” Tallamy says. (1)
How many caterpillars must a pair of parent-chickadeess find and feed their young--to keep the species alive ? 6,000-9,000 to raise just one clutch, says Professor of Entomology & Wildlife Ecology at University of Delaware, Doug Tallamy.
Talk about long work hours.
In facing climate change, we often look for the hardy, the survivors. But will these same survivors help us reverse climate change?
How about the gingko tree, famed survivor, rooted to our planet even in the age of the dinosaur: If it survived whatever took out the dinosaurs, surely it'll survive anything!
The gingko, aside from its beauty, and medicinal assets, helps to sequester carbon. It produces its famous berries, but birds require most of their nutrition from insects, not from berries.
And the gingko supports just one kind of caterpillar. It's hard to find 6,000-9,000 of one kind of caterpillar to raise a clutch of chickadees.
On the other hand, consider the native oak tree. Like the gingko, the oak provides beauty and shade. It sequesters carbon. But check out the rest of its resume : it provides cover for wildlife, nest site for birds, produces pollen, provides food for wintering birds and for breeding birds, food for spring and autumn migrating birds, food for mammals, and . . . for caterpillars.
Native oaks provide food for 534 kinds of caterpillar.
Now to our traditional way of garden-thought, this might seem an argument against the native oaks! Who wants to see a caterpillar-devoured oak tree in their garden? But the oak is not descended upon as by locusts. WE generally don't see the caterpillars. Someone else does : BIRDS.
"Home to 82 percent of the nation’s population, cities and suburbs in the United States also house two-thirds of all North American wildlife species, including many imperiled plants and animals." (2)
Species extinction may seem like a remote problem, to those of us living in major cities, but current research documenting local species loss (from plants in Hudson River to varieties of lichen in the NorthEast corridor) shows us that we are far from immune to loss of biodiversity and its potentially devastating consequences. A third of birds in North America are facing extinction. (3)
"No one has taught us that we have forced the plants and animals that evolved in North America (our nation’s biodiversity) to depend more and more on human-dominated landscapes for their continued existence. We have always thought that biodiversity was “happy somewhere out there in nature”: in our local woodlot, or perhaps our state and national parks. We have heard nothing about the rate at which species are disappearing from our neighborhoods, towns, counties, and states. Even worse, we have never been taught how vital biodiversity is for our own well-being." (4)
Our gardens tend to be rather insignificant, compared to a national park. But if we begin to include plants and planting patterns proven to support our local ecosystems, our collective gardens can turn back the tide and restore the biodiversity of our local habitats and by extension, help restore our planet's (and our own) health.
So if you are choosing a tree for your garden, consider the mighty oak. And also check out Rick Darke and Doug Tallamy's The Living Landscape, which explains in detail how to plant your garden for beauty, yes, and also to offer much-needed support for our diverse plant and animal populations--many of whom live right along side us in our cities and suburbs.
RECOMMENDED OAK TREES (5):
Quercus alba / White Oak
Quercus bicolor / Swamp White Oak
Quercus coccinea / Scarlet Oak
Quercus falcata / Southern Red Oak
Quercus macrocarpa / Burr Oak
Quercus marilandica / Blackjack Oak
Quercus montana / Chesnut Oak
Quercus palustris / Pin Oak
Quercus phellos / Willow Oak
Quercus rubra / Red Oak
Quercus velutina / Black Oak
"Studies have shown that even modest increases in the native plant cover on suburban properties raise the number and species of breeding birds, including birds of conservation concern. As gardeners and stewards of our land, we have never been so empowered to help save biodiversity from extinction, and the need to do so has never been so great. All we need to do is plant native plants!" (6)
(1) (2) National Wildlife Federation : Creating Bird-Friendly Urban Landscapes https://www.nwf.org/News-and-Magazines/National-Wildlife/Gardening/Archives/2013/Bird-Friendly-Urban-Landscapes.aspx
(4) (6) American Forests : A Call For Backyard Biodiversity https://www.americanforests.org/magazine/article/backyard-biodiversity/
(5) The Living Landscape by Rick Darke and Doug Tallamy ©2014 by Rick Darke & Doug Tallamy, published by Timber Press.