The great expanses of turf grass in our American landscape—60,000 plus square miles—have created a sterile monoculture that is costly, chemical and water dependent, and time consuming to maintain. One of the most significant contributions we can make to biodiversity is to limit turf grass to areas that make sense such as paths, outdoor ‘rooms’, and recreation areas. If 50 percent of turf grass in our landscapes were converted to native plantings consisting of non-invasive groundcovers, native grasses, shrubs and trees, we would transform our environment and create habitats for birds and wildlife. We would also increase stormwater infiltration and improve water quality, not to mention create identities for our neighborhoods.
Larger areas can be maintained as meadowlands and mowed once every one to three years after ground dwelling birds have raised their young. In suburban developments, these contiguous meadow landscapes can create grasslands that slow down stormwater, reduce erosion and create habitat. Birds that once populated grasslands such as the bobolink and eastern meadowlark are becoming scarce in our area because of the lack of meadow habitat. Creating meadows in place of expanses of turf grass can contribute to their survival.
Converting turf areas to native plantings also reduces our carbon footprint by eliminating continual mowing and chemical fertilizer, herbicide, and pesticide applications. Trees, shrubs, and native meadow plantings have greater capacity to sequester carbon in their plant tissues and help reduce greenhouse gases. Reduction of turf areas means less valuable drinking water expended on watering lawns. Areas converted to a complexity of plantings are more efficient at absorbing stormwater because leaves, branches, stems, and understory vegetation slow down water so it can be absorbed into the soil more easily.
A native plant is one that is indigenous and occurs naturally in a particular area as opposed to being introduced. To expand our plant palette, plant breeders have produced ‘cultivars’ of many native plants. Garden worthy non-native plants that are not invasive may also create backyard habitats such as crabapple trees that provide fruits and shelter for migrating birds. However, the opportunity to plant native varieties should be explored first, since they have been historically neglected and often face tremendous pressure in the wild from competing invasive plants and predators such as deer. Gardeners are in the unique position of being able to create a genetic repository for rare and endangered native plants in their home landscapes.
Hand-in-hand with planting native and non-invasive plants is removing and avoiding use of invasive plants, the second most detrimental environmental challenge next to habitat loss. Invasive species can be defined as non-indigenous species of plants or animals that adversely affect habitats economically, environmentally, or ecologically. Most invasive plants are from Europe or Asia and have a history of thriving alongside human development.
Some plants such as Norway maple, a threat to our own sugar maple—the New York State tree—are still to be found in the nursery trade, so it is important to be an informed consumer. Not all non-native plants are problematic. It’s easy to familiarize yourself with the most aggressive plants so that you can first remove them and then avoid introducing new ones into your landscape. The Brooklyn Botanic Garden has two excellent handbooks: Invasive Plants: Weeds of the Global Garden and Native Alternatives to Invasive Plants. The New England Wildflower Society has detailed information on invasive plants, identification, removal, and alternatives at newfs.org.
Landscapes that employ native plant associations as a model for design can provide a richness of biodiversity and variety of habitats. The ‘layers’ found in a forest edge association (low groundcover layer, medium height shrub layer, and higher tree canopy) can be duplicated in your garden and provide a variety of exposures from sun to deep shade. Native plants evolved with our birds and insects and provide the essential basis for the local food web. Berries and fruits found on trees and shrubs such as serviceberry, gray dogwood, inkberry and winterberry not only provide food for migrating birds but offer seasonal interest in leaf, bud, bark, flower, and fruit.
Many of our spectacular butterflies and moths are species-specific when it comes to their caterpillar stage. Without the specific host plants for butterfly larvae there will be no butterflies. This is exemplified by the monarch butterfly, whose larvae only eat plants in the milkweed family. The spicebush swallowtail is similar in its preferences, and planting American spicebush will help attract this species. Homeowners who develop their properties into more sustainable landscapes can enroll in the National Wildlife Foundation’s Backyard Habitat Certification program nwf.org.
There are so many aspects of design and maintenance of the residential landscape and many more possibilities for sustainable features like edible landscapes, permeable paving, rain gardens, wetland gardens, water harvesting, lawn alternatives, and more.
Barbara Z. Restaino is a Registered Landscape Architect, LEED Accredited Professional, and principal of Restaino Design Landscape Architects, PC in Grahamsville, NY. Info@restainodesign.com.