Looking out the window at the grayness of winter, thoughts turn to spring and inevitability to birds and plants. Winter is a good time to take stock of the property and plan for the spring’s gardening. Intelligent gardening is applied ecology. Gardens play an increasingly important role in protecting our unsustainably declining biodiversity as too much habitat has been lost, fragmented, or degraded and increasingly our wildlife has no place to go. Even for obligate forest interior bird species, a well planted garden can be a welcomed migration stop. Birds need food, cover, and water. A well-planned garden can provide those needs.
If I want a healthy bird population on my land, I need a healthy diversity of native plants that attract a healthy diversity of native insects, not alien plants that produce toxins to which native insects have not adapted. I need to garden organically so I don’t poison the invertebrates that are part of a healthy ecosystem and provide essential protein for young birds of all species. I need to plan for a secession of berries from late spring to winter so there is food year-round for berry-eating species. I need plants that attract pollinators to ensure that my berrying shrubs produce well.
Native dogwoods, genus Cornus, are among our most valuable plants for birds. Eaten by ninety-eight species of birds, dogwood berries have a high lipid content that make them especially valuable for migrating birds. Migrating thrushes co-evolved with the Flowering Dogwood, Cornus florida. Unfortunately, because of problems with anthracnose disease, Flowering Dogwood has been too often replaced by Kousa Dogwood, which berries at the wrong time for migrating birds, if it berries at all. Ironically, Kousa Dogwood was probably the source of the anthracnose fungus. Not only do non-native plants provide sterile habitat, they too often introduce devastating fungal diseases and insect pests. Planting flowering dogwood in an area out of full sun in a more natural wooded setting helps mitigate the fungal problem. Other native dogwoods, especially the white berrying ones such as Gray Dogwood, Cornus racemose, are excellent wildlife plants.
Going native is easier said than done. The landscape and nursery industries are slow in understanding the need. When we replaced dead trees in an area that needed an evergreen buffer, we asked our landscape architect for native red cedar. He sent us a plan with a red cedar/ Chinese cedar hybrid, favored in the trade for its near perfect shape. We insisted on the native red cedar Juniperus virginiana. He replied “Oh, you want the one with the blue berries.” Yes, we want the one with the blue berries that help keep our bluebirds, waxwings, myrtle warblers, robins, and over fifty other bird species alive all winter. We want the one that is a functioning member of our ecosystem, not the one that is aesthetically pleasing but sterile. The non-native cultivar should not be more readily available and less expensive than the native plant. Consumers need to push the industry toward native.
Fortunately, there is a growing grassroots movement toward planting native, both in ecological restoration in preserves and on private property. The planting of pollinator meadows on school properties is especially heartening as it engages the younger generation. WCAS continues to support native planting through Holden Grants. We had a record number of requests for invasive species control and native plant replacement this year from grassroots groups that are improving wildlife habitat in their local preserves. If home owners will fill in the gaps between preserves by planting native, connecting corridors would form that would ultimately create a vibrant sustainable natural community.