There are four ecological functions every landscape must perform if we are to achieve a sustainable relationship with the natural world that supports us (and continuing to insist on landscapes that do not sustain mother nature is not and has never been a realistic option). It’s really very simple; our landscapes must do the things that enable ecosystems to produce the life support we and every other species requires.
Four Landscape Ecological Goals
1) They must support a diverse community of pollinators throughout the growing season.
2) They must provide energy for the local food web.
3) They must manage the watershed in which they lie.
4) They must remove carbon from the atmosphere where it is wreaking havoc on the earth’s climate.
How well a landscape accomplishes these goals depends on how well we, as landscape managers, choose and deploy the plants on our landscapes.
Lawns fail at these 4 goals:
If we plant most or all of our property in lawn, none of these goals will be met. More often than not, lawn degrades the local watershed by discouraging infiltration, facilitating stormwater runoff, and adding nitrogen, phosphorous, herbicides, and insecticides to the nearest stream or river. Today’s cultural standard for lawn supports no pollinators and does not nourish the insects that enable birds, reptiles, amphibians and, many mammals to reproduce. And when it comes to carbon capture, turf grass is our worst plant choice. Yes, lawn grasses do build their tissues out of carbon they have pulled from the atmosphere, but every time we mow the lawn, we release that carbon back into the air. Grass roots, like the roots of other plants, do leak some carbon into the soil, but grass roots are very short, and almost any other plant species deposits more carbon into surrounding soils than does grass. Finally, every time we mow, we belch carbon from fossil fuels into the atmosphere.
Native Plants succeed at these 4 goals:
We can help our yards meet their ecological responsibilities by planting the plants that are good at supporting pollinators, good at sharing some of the energy they have harnessed from the sun with the local animals that run our ecosystems, good at building their tissues out of carbon and holding it within their structures, out of harm’s way, for decades or even centuries; and good at producing glomalin on root hairs, a carbon-based structure that deposits so much carbon in soil that it becomes brown or black. We can also choose plants with large canopies that soften the impact of pounding rain, and that support large root systems that encourage rainwater infiltration and thus hold tons of water on site after a storm event.
Transforming our yards into these ecological gold mines is a process, one that can unfold over months, years, or even decades. Every time we plant a native perennial that nourishes specialist bees, we have helped all local pollinators, for generalist bees can use those plants as well. Every time we add a native oak, willow, cherry, birch, cottonwood, alder, maple, etc. to our yard, we have reduced the ecological dead zone we call lawn and increased the ability of our yard to support breeding birds by supplying the host plants for the caterpillars on which those birds rely. Moreover, such plantings have vastly improved our yard’s watershed management and carbon sequestration potential.
We don’t need exact measures to know we are moving in the right direction. Simple estimates can help us evaluate the progress we have made and the amount of life support we have enabled our local ecosystem to produce, not just for us and the other species in our yards, but for all of our neighbors as well. How much lawn have we eliminated? How many trees have we added? How many new flowerbeds or simply beds mulched with leaf litter have we built? How many invasive plants have we identified on our property and targeted for removal? How many birds, butterflies, and bees have we seen taking up residence in our yards? These are all measures of success and noting any of them will motivate us to do more.
The path to sustainability lies along a continuum, with low (or no) ecological function at one end and a vibrant, ecological machine churning out ecosystem services every minute of every day at the other. Every time you take action, your landscape moves closer to becoming a positive ecological force rather than a negative one. Our current landscaping paradigm has been making withdrawals from the ecological bank account that supports us for far too long. By helping our properties reach the four ecological goals described above, we can finally start making life-saving deposits.
From the Home Grown National Park website by Doug Tallamy