 |
| Heated deck bird bath provides water in winter |
Driving by the large, wooded area at the far edge of our neighborhood, my son and I often saw rabbits feeding and on fair nights, with the windows down, we heard the song of spring peepers. In the mid-1980’s posted zoning signs were replaced with store names and construction began. My son asked, as bulldozers toppled trees and turned the woods into a large swath of dirt, “Where will the bunnies go?”
Statistics
bear out the significant increase in human population and the millions of acres
each year that are taken from native habitat for housing, commercial and
industrial uses. Along with these numbers research shows that song birds, meadow
birds and their food sources are in great decline.
Beyond the
benefits of home food production and increased property values, today suburban
landscapes are becoming the lifelines for plants and animals that have lost
their native habitat to development. As development continues wildlife is
forced to depend upon our human-dominated landscapes for their continued
survival.
What is planted
in home landscapes plays an important role in determining the future of
wildlife. “[G]ardeners have the power to make a significant contribution”
toward variety in both plants and animals wrote Dr. Douglas Tallamy in his
book, “Bringing Nature Home.” Establishing areas of biodiversity is important
to saving our wildlife.
“Biodiversity
refers to the richness or variety of animal, plant, and other life in a given
area, from the tiniest snail or plant to the largest predator,” wrote Dr. James
Finley, Professor of Forest Resources at Penn State.
Biodiversity embraces all
living things, including humans, and how their existence and survival are
interconnected. What each plant and animal provides and needs creates a web of
interdependence. As an example, plants need insects for pollination and insects
need plants for food. Birds need insects and the berries and seeds from plants
as food.
Tallamy, Professor
of Entomology and Wildlife Ecology at the University of Delaware, notes that historically
home gardens focused on creating beautiful surroundings, expressing artistic
talents with design, and making areas for fun and relaxation. Recent trends show
a new focus on design to provide refuge for wildlife and support animals
including birds, pollinators and other insects as well as native plants.
The Herb
Society of America's Green Bridges Program™ promotes the idea that individuals
can contribute to building a national chain of yards, gardens and communities
that support biodiversity, especially for native plants and pollinators. There
are four key things that home gardeners can do to support biodiversity: add
native plants, support pollinators, reduce lawn area and create an environment
that supports the needs of wildlife.
One of the
most important things to do is to add native plants, those that grow naturally
in our area. Native plants are the most hardy and likely to thrive with less
disease or insect problems. Some native plants also filter air and water as
well as help maintain soil health. Many ornamental plants, though beautiful,
are from Asia and Europe and are avoided by native insects.
Tallamy
describes the importance of native plants by explaining that “[a]ll animals get
their energy directly from plants, or by eating something that has already
eaten a plant. The group of animals most responsible for passing energy from
plants to the animals that can’t eat plants is insects. This is what makes
insects such vital components of healthy ecosystems. ”
Insects, as
reported by the
Natural Resources Conservation Service, make up 99.5% of
pollinators. “Pollinators are the very foundation of biodiversity. Almost 90%
of flowering plants require animal assisted pollination,” said Laurie Collins,
Master Gardener. “In addition to one third of our food, they pollinate other
species of plants that provide food and shelter to wildlife.”
Collins also
noted that pollinators – bees, other insects, butterflies, birds, bats, and
mice – need the plants for shelter and food. Adding host and nectar plants that
support pollinators is only half the solution. Correct use of herbicides and
insecticides is just as important.
A typical
suburban lawn does not support biodiversity. Cornell University reports that
compared to native vegetation, non-native heavily treated turfgrass is a
biodiversity wasteland. While some sources suggest replacing lawns with native
grass, Dr. Peter Landschoot, Director of Graduate Studies in Agronomy at Penn
State, notes in our area native grasses are warm-season species. “They stay
dormant for most of the year and become overrun by weeds.” He says that
property owners need to be comfortable with having grass at heights of 6-18
inches, not always welcome in residential neighborhoods.
Instead convert
lawn areas by adding native trees and understory plants to the landscape. This
can be along the perimeter or in small areas throughout the property. Tallamy
notes that studies show that modest increases in the native plant cover in
suburban yards significantly increases the number and species of breeding
birds. Additionally, by using lawn space for native plants home owners can
reduce the costs of lawn maintenance such as heavy watering, mowing, pesticide
and fertilizer applications.
Native trees
such as white oaks (Quercus alba), black willows (Salix nigra), red maples
(Acer rubrum), green ashes (Fraxinus pennsylvanica), and river birches (Betula
nigra), under-planted with woody perennials like serviceberry (Amelanchier
canadensis), arrowwood (Viburnum dentatum), and blueberries (Vaccinium spp.)
are excellent choices for Pennsylvania properties.
Landscape
design can help reverse the human-caused habitat loss by providing some or all
of the four needs of wildlife: food, water, shelter and nesting areas. The
National Wildlife Federation (NWF) website has practical suggestions for
meeting those needs. Once gardeners have met these needs they can apply to the
NWF for a Garden for Wildlife ™ certification.
Providing
food can be as simple as seed and suet feeders but including native plants with
seeds and berries is important as well. Bird baths are typical for home gardens
but rain gardens or ponds can provide water sources that serve frogs and other
wildlife. Providing water year-round is important and for bird baths can be
accomplished with a heat source or by swapping out containers during the day.
A rock wall,
evergreen tree, wooded area or water garden offers cover from predators. From
plain to decorative, birdhouses are some of the best nesting areas when placed
correctly. Other nesting sites include mature and evergreen trees, dead trees
and even caterpillar host plants such as milkweed. It is also important to make
the garden safe for wildlife by protecting the air, water and soil by
eliminating or reducing herbicide and pesticide use and adding compost to the
soil.
The shifting
relationship between humans and the environment has changed the balance of
nature. Home gardens are an important building block, along with community
gardens, parks and other natural spaces, to replacing lost habitat. Gardeners
can help restore some of nature’s balance by designing their landscape with the
needs of wildlife in mind.
~ Carol
Kagan, Penn State Master Gardener
