For those of us with lawns to care for, autumn often comes with the laborious tasks of raking up fallen leaves, removing expired garden plants, and putting yard waste into paper bags to be carted off for city processing.
Preparing the lawn or garden bed for spring is another common fall chore, with many retailers of lawn and garden products recommending that homeowners fertilize their lawns during autumn while the grass is still able to process nutrients.
Unfortunately for the environment, these standard practices are unsustainable and contribute substantially to human-caused degradation of the planet’s ecosystem.
Why are these practices unsustainable? For municipalities without green bin programs (which, as of 2016, has been 407 out of 444 in Ontario) these yard waste products are added to regular landfills, eventually decomposing to produce potent greenhouse gases (GHGs) such as methane.
When compared to carbon dioxide—the ubiquitous and most commonly discussed GHG—methane is estimated to be 28- to 36-times more potent at contributing to global warming. Decomposing yard waste also releases acidic compounds, which allows other toxins from garbage in the landfill to more easily leach into the soil, air, and water.
While Ottawa does have a green bin program that accepts yard waste, the removal and transportation of bagged leaves requires a fleet of garbage trucks, burning fossil fuels along their neighborhood routes and transportation to and from central waste processing and storage facilities.
This also produces significant quantities of GHGs—further contributing to global climate change—in addition to contributing to smog and acid rain, and worsening air pollution known to be harmful to human health.
As for autumn lawn fertilizing, a significant proportion of synthetic fertilizer applied to lawns (40 to 60 per cent) ends up in the public water system, contaminating local and regional water cycles with excess nutrients.
This contributes to eutrophication of freshwater bodies (lakes, ponds, streams, etc.)—meaning all these nutrients lead to such rapid aquatic plant growth that the vegetation absorbs all available oxygen in the water, slowly suffocating fish and other aquatic life to death. It may also cause blooms of toxic blue-green algae and contamination of drinking water supplies.
The chemicals in fertilizers can also cause chemical burns to your pets’ feet if they walk on the lawn recently after application (and more severe health problems if ingested), as well as skin and eye irritation for humans. The practice of lawn fertilization is wasteful of fertilizer that could be put to better use, such as when cultivating naturally nutrient-poor areas—where using these chemicals would actually be warranted in small amounts.
These poisonous chemicals pose public health concerns but would be totally unnecessary if people stopped raking fallen leaves off their lawns and allowed them to biodegrade into the ground over winter instead.
Leaves and dead plants actually act as natural mulch and fertilizer when left on the ground, removing the need for chemical nutrient replacements. Leaf litter and the stalks of dead plants will also boost the biodiversity of your (and your neighborhood’s) ecosystem, as they are important habitats for small wildlife such as pollinators, toads, frogs, and other insects. Birds that remain in cold climates over winter also depend on this ‘waste’ as a source of food during the season where food resources are at their scarcest.
Through the simple act of not raking leaves or cleaning up the garden bed, you are helping protect biodiversity, providing local habitat for wildlife, helping birds over winter in our severe Canadian climate, preventing the unnecessary application of synthetic fertilizer to your yard, and preventing the host of human-caused ecosystem damage that comes from the standard practices of autumn lawn and garden care.
Not only is this beneficial for your local ecosystem, it saves ourselves the time and energy required to carry out these chores. This year, consider not taking on the tasks of autumn yard work, for both the benefit of local wildlife, reducing water and air pollution, lowering GHG emissions, and for your own schedule’s benefit.
In the words of John Lennon, when it comes to caring for your yard this autumn—just let it be.
Featured image by Christianna Alexiou.
