Be cautious when selecting vines because there are some very invasive types (such as certain commonly planted nonnative varieties of honeysuckle and wisteria) that will take over. Opt for the native varieties so that wildlife will find what they need.
Perhaps the most critical layer for overall garden health lies below our feet: the ground layer. It includes several zones on the surface and below. Ground litter includes all kinds of plant and animal droppings, seeds, twigs, leaves, and dead wood, and it serves many purposes. It provides insect cover and food, retains moisture, and holds microhabitats for fungi, bacteria, and other microbes that break down the litter into soil.
The ground layer contains more life forms than any other layer. On the surface of the soil, you’ll find mosses, algae, salamanders, and beetles, to name a few. Underground, most insects spend at least part of their life cycles in the soil, as do many reptiles and amphibians. As for the impressive “roof” or canopy, it wouldn’t be there without a foundation. The root systems of trees extend out from the trunks at least as far as the canopy branches and reside mainly in the 2- to 3-foot depth, where oxygen is available in the soil. Native grasses and wildflowers may grow deep taproots that plunge 6 feet or more into the earth. A community of mycorrhizal fungi and microbes release organic compounds into the soil that feed the plant roots.
In contrast, mowed turf grass adds very little support to the ecosystem, and the soil compacted by riding mowers makes is almost impermeable to water. Herbicides that kill forbs prevent a biodiverse system from establishing itself, and they set off a cycle of spot treatments for symptoms without addressing the underlying systemic malfunctions.
Likewise, removing nature’s nutrient-rich gift—fallen leaves—takes away the soil-enriching and biodiverse benefits that leaf litter provides. Then we have to go out and buy topsoil, fertilizer, and compost; haul it home; and blend it back in to amend the soil. Douglas Tallamy sums up the wasted effort: “Plants make leaves, and we all freak out and get our leaf blowers and our rakes, we rake up all the leaves and put ‘em in bags and treat ‘em like trash. Then we run to Home Depot and buy mulch, fertilizer, hoses, trying to replace the ecosystem services we just threw out, but we can’t replace the arthropods we got rid of.” If we can let leaves stay where they fall or chop them up with a lawn mower and rake them to cover our garden beds, we’ll be on our way to sharing the gardening work with Mother Nature instead of doing all of the work ourselves.
Zinnias add a splash of color and plentiful nectar to your garden.
Switchgrass is a native grass that can grow several feet high.
The ground layer nurtures both plant and animal life.
Understand the Food Web
You’ll read about birdscaping and gardening for beneficial insects later in this book, but keep in mind that you cannot really garden for a particular type of wildlife exclusively. As Marlene Condon explains in Nature-Friendly Garden, “When you grow nectar plants for butterflies and hummingbirds, you will also attract moths, wasps, bees, and many other kinds of insects.” Spiders and caterpillars will feed on them, and they will attract birds. Maybe even deer will join the party. Condon goes on to assert, “You need to accept that all of these creatures are part of your world and include them in your garden planning.” This is our garden’s food web.
We all know the concept of “the big fish eat the little fish.” What do the little fish eat? Algae, plankton, insects. What do insects eat? Start with any food or animal, follow this thread to its source, and eventually you wind up at plants and, ultimately, the sun. Practically all life on Earth depends on the sun’s energy, which is captured by leaves and photosynthesized. An animal eats the plant and absorbs energy, which is transferred to the next animal and so on. This is a food chain.
Every food chain consists of producers, consumers, and decomposers. Plants are the main producers. Consumers are generally categorized as herbivores (plant eaters), carnivores (meat eaters), and omnivores (both plant and animal eaters). Decomposers help break down the nutrients and minerals and recycle them back into the system, which makes the system not such a straight line. There could be many food chains that interrupt or interconnect with each other. The term food web describes the various interweaving parts of food chains.
As with a spider’s web, if one strand is broken, many others remain in place and do the same job. In permaculture, this is referred to as redundancy—the concept that multiple elements provide the same function. Redundancy puts less stress on any single member of the system, which is why more biodiversity, or a variety of life forms, helps increase a system’s stability and resiliency. Lose one? No big deal. Another will fill in until balance is restored. A monoculture, on the other hand, which features a single predominant species, is more vulnerable to disease or predation. For example, many housing subdivisions are planted with one type of street tree. If you lose one, you might lose them all.
In Peter Bane’s Permaculture Handbook, he compares our knowledge of our plant ecosystem with that of our ancestors. “The average Cherokee woman at the time of European contact knew and used approximately 800 species of plants for food, fiber, and medicine.” Most vegetable gardeners today would be doing well to have thirty to fifty species growing, and, in a permaculture garden, that number could be multiplied by ten. Commercial, governmental, and industrial growers are not necessarily concerned about the heritage that they lose by decreasing plant diversity. It is up to the small-scale growers to preserve the native plants and heirloom fruits and vegetables and keep trying new ways to diversify the garden.
Know that Your Garden Matters
Douglas Tallamy, in Bringing Nature Home, explains why every plant decision you make is important. “Because food for all animals starts with the energy harnessed by plants, the plants we grow in our gardens have the critical role of sustaining, directly or indirectly, all of the animals with which we share our living spaces. The degree to which the plants in our gardens succeed in this regard will determine the diversity and numbers of wildlife that can survive in managed landscapes. And because it is we who decide what plants will grow in our gardens, the responsibility for our nation’s biodiversity lies largely with us.”
Bee balm (Monarda spp.) attracts bees, butterflies, and birds with its nectar.
Your property, with the ecosystem services it provides, is your place to make a difference in the world. The United Nations Food and Agriculture Organization (FAO) defines ecosystem services as “the multitude of benefits that nature provides to society.” The ecosystem comprises all living and nonliving parts of the environment and their interactions that benefit the world. Those essential services and benefits include cleaning the air, purifying water, providing spiritual connections, pollinating, stabilizing and forming soil, and providing recreation. The FAO estimates that all of this collectively adds up, worldwide, to a value of $125 trillion; however, “these assets are not adequately accounted for in political and economic policy, which means there is insufficient investment in their protection and management.”
Tallamy and Darke delve further into the role of the garden in the larger environment in their book The Living Landscape. Ecosystem services that your very own garden can contribute to include:
• supporting human populations
• protecting watersheds
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