I’ve recently read two books that I recommend to any gardeners intent on cultivating their gardens as havens for wildlife, The Once and Future World by J. B. MacKinnon (2013, Houghton Mifflin Harcourt) and Moral Ground: Ethical Action for a Planet in Peril, edited by Kathleen Dean Moore and Michael P. Nelson (2010, Trinity University Press). The later book is a collection of more than 80 short essays by such visionaries as Wendell Berry, Dalai Lama, Alison Hawthorne Deming, John Paul II, Barbara Kingsolver, Barack Obama, Gary Snyder, Terry Tempest Williams, E. O. Wilson, Daniel Quinn, Paul Hawken, and many others.
Taken together, these works describe a planet in peril. Consider the words of environmentalist James Gustave Speth in his contribution to Moral Ground:
“The human presence is now so large that all we have to do to destroy the planet’s climate and ecosystems is to keep doing exactly what we are doing today, with no growth in the human population or the world economy. Just continue to release greenhouse gases at current rates, just continue to impoverish ecosystems and release toxic chemicals at the current rates, and the world in the later part of this century won’t be fit to live in.”
Or this 2007 quote of Ahmed Djoghlaf, head of the UN convention on biological diversity, taken from Daniel Quinn’s essay in Moral Ground:
“Extinction rates are rising by a factor of up to 1,000 above natural rates. Every hour, three species disappear. Every day, up to 150 species are lost. Every year, between 18,000 and 55,000 species become extinct. The cause: human activities.”
Accepting that the human species has changed the world forever, and not for the better, MacKinnon’s book introduces the concept of “rewilding”, a term coined in the early 1990s by David Foreman, a founder of the Earth First! environmental network. “Rewilding” evokes the creation of places made wild again, places where biodiversity flourishes.
Gardeners, the caretakers of private gardens, public gardens, and all other managed landscapes such as campuses and parks, can be instrumental in rewilding these places. The essence of this work would be an emphasis on use of native plants that provide food and shelter for wildlife, and the use of gardening techniques that foster biodiversity above and below ground, including the use of organic fertilizers and mulches while avoiding the use of any toxic chemical. Gardening success would be measured by the number of species of native plants, insects, other animals, and microorganisms living in the garden.
An Example of Rewilding
Rewilding our gardens means letting go of our attachment to non-native plant species, particularly those proven to be invasive, replacing them with ecologically-functional native plant species. A good example would be ridding coastal New England gardens of invasive non-native rugosa roses (Rosa rugosa) and, in their place, cultivating wild roses such as R. carolina, the pasture rose, native to the entire eastern half of the U.S.
The rugosa rose, often sold as “beach rose”, easily escapes cultivation in coastal gardens as a result of bird-dispersed seed. As a result, it can be found in dense stands on the upper limit of beaches, dunes, and coastal headlands where it impedes the growth of native plants. I have watched such an invasion progressing over the past decade on Vinalhaven, an island off the coast of Maine. There, in the open fields bordering the rocky coastline, I’ve watched colonies of beach rose expanding, swallowing up space previously occupied by native plants such as northern bayberry, meadowsweet, sweet fern, and native rose. No doubt, this invasion started with the first shipment of beach roses brought from the mainland to an islander’s garden.
Despite its beauty, beach rose should be viewed as a serious threat to the integrity of all coastal communities. There are still areas of New England that can be protected from this invader and other areas that can be reclaimed, but only if we stop growing beach roses in our gardens.
While not as fragrant as beach rose, nor as long-flowering, R. carolina, the pasture rose, is the ecologically-functional alternative. It has lovely simple flowers, a single row of pink petals surrounding bright yellow stamens, and its autumn display of burgundy-red foliage and deep red hips more than compensate for the shorter flowering season.
Insect visitors to the flowers of pasture rose are pollen feeders, as the flowers provide no nectar. Many of these visitors are important pollinators, including long-tongued bees, such as bumblebees. Other insects, including green metallic bees, syrphid flies, and various pollen-feeding beetles, also visit the flowers but are less effective pollinators. Caterpillars of many moth species feed on the leaves, while the hips (fruits) are eaten by game birds, rabbits, skunks, and white-footed mice, all of which help to disperse the seeds across considerable distances in the wild.
Pasture roses in Marjorie’s Garden form a colony, as is their habit, around the trunk of an old yellow birch on the edge of the drainfield. Unlike non-native roses, their demands are minimal, a little care with the lawn mower to avoid cutting off any of the numerous suckers that form each summer and mulching with composted manure every other year or so. In return, we enjoy watching small native bees gathering pollen from their flowers every summer and the resulting display of hips come autumn. We also enjoy the summer-long display of glossy green leaves, even on plants growing in the shade; flowering may be reduced by the low light, but the foliage makes for an excellent ground cover.
To create a striking year-round garden scene, consider interplanting pasture rose with another highly functional native shrub, northern bayberry (Myrica pensylvanica). The dark green foliage of bayberry makes an excellent background for the simple pink flowers and deep red autumn hips of pasture rose. I cannot take credit for this design, however, as it is a common sight along the wild rocky coast of Maine.
(Author’s Note: Your local nursery or garden center may not carry pasture rose, but they may be willing to find some for you. As of this writing, Pierson Nurseries in Biddeford Maine, a wholesale grower, carries Rosa carolina. They can be found on the Internet at: http://www.piersonnurseries.com/.)