Not so 'green' outcomes of the American lawn
Lawns are culturally and perceptually favorable, yet their environmental effects prove to be quite the opposite
The grass is always greener in part stems from the idea that someone else has it better or is otherwise more fortunate. Lush, green, expansive grass is symbolic of status and wealth. Such a lawn is visible to any and all passersby and those in one’s neighborhood. While this largely may not be a conscious perception when maintaining a lawn, it has become a habitual and normalized point of pride to have a lawn on one’s property. By having a lawn, one indicates that they have the time and resources to maintain it and ensure that it is well-kept. While many of us do not grow our own food, the use of land to be purely decorative rather than for crops can serve as an outward indication of wealth and prosperity (Planet Natural Research Center). The general use of lawn has surpassed corn, the nation’s largest irrigated crop in terms of irrigated acreage. Princeton University details that over 400 million acres are attributed to lawn use (PSCI 2020). This is quite a large and somewhat surprising realization given that we tend to allocate such a magnitude of land for aesthetic purposes.
The resources that it takes to maintain a well-kept lawn can indicate a form of status and prosperity. These resources, utilized on a large scale can have harmful and deleterious effects on the environment that often go unrecognized or unnoticed. The environmental costs of having a lawn are high and outweighs the environmental benefits. Does having a lawn have any environmental benefits? Lawns can function as carbon sinks, which can absorb carbon dioxide from the atmosphere (PSCI 2020). This is beneficial as we recognize that higher levels of greenhouse gases accumulating in the atmosphere are harmful to the planet. However, the environmental cost that it takes to maintain a lawn outweighs the carbon-storing benefits that a lawn can provide. The environmental cost tacked on to a lawn in part includes the equipment, which PSCI references gas-powered mowers and leaf blowers as well as fertilizers. This can net out to around 800 million gallons of gasoline each year with approximately 17 million gallons wasted in spillover (PSCI 2020).
The mowing machines themselves tend to be inefficient and certain models can release toxic gases into the air. The California Air Resources Board reported in 2017 that, “By 2020, gas-powered leaf blowers, lawn mowers, and similar equipment in the state could produce more ozone pollution than all the millions of cars in California combined” (PSCI 2020). We recognize that transportation has a significant and notable role in fuel use and greenhouse gas emissions, but lawn movers are far less top of mind in our considerations.
Runoff from fertilizer and pesticides can pose issues in lakes and rivers by polluting them. These chemicals increase toxicity levels and can cause algae blooms that deplete resources from otherwise naturally occurring habitats. Approximately 3 million tons of such nitrogen-based fertilizer are used by American homeowners annually to maintain lawns (PSCI 2020). Runoff of such products can contaminate water with surplus levels of phosphorus and nitrogen, rendering it unsafe for drinking (Home Guides 2018). Not to mention the sheer volume of water it takes to maintain lush green lawns. The process of making the fertilizer requires vast amounts of carbon and the soil itself cannot absorb and hold the amount of nitrogen from the fertilizer, thus it finds its way to disadvantageous places. Additionally, soil microbes turn the surplus nitrogen from the fertilizer into nitrous oxide, a greenhouse gas, and a harmful one at that (PSCI 2020).
It turns out that greenhouse gases are not created equal. Carbon dioxide tends to get all the credit (or infamy) for being the billboard name for the greenhouse gases (GHG). All the other greenhouse gases are compared to or based off of carbon dioxide, so it is given a Global Warming Potential (GWP) of 1. The greenhouse gas mentioned above, nitrous oxide, has about 300 times (298 GWP) the heat trapping capabilities as carbon dioxide (Ecometrica 2020). Unfortunately, this is not the highest-powered GHG or even close to it – the article with this list is referenced below in the sources.
Despite the harms behind maintaining a lawn, some of the beneficial cultural perceptions and the habitual nature of owning a lawn discourages homeowners from scrapping their slice of the American dream. Lawns can be a great place for kids and pets. However, the use of fertilizers and pesticides can be harmful for both groups as well as the environment and should be noted and managed with care. For those who do not want to give up their lawns, PSCI recommends opting for an electric mower and/or mowing less often. Additionally, upgrading gas cans can reduce amount of spillage, and looking to mow in the evening allows for less interaction of chemicals with sunlight (PSCI 2020).
Despite the lovely green look that we have come to appreciate, the maintenance and upkeep of lawns themselves is not ‘green’ or eco-friendly. Lawns for homeowner and household use as well as commercial and sporting use play a harmful and unsustainable role in climate change. It is helpful to hone in on and evaluate perceptions of what is means to have a lawn and why many of us choose to maintain and divert efforts toward them. Lawns have become so common and integrated into the American homeowner experience that we often place little thought on their presence or commitment to upkeep. Lawns can instead be replaced with natural shrubbery or wildflowers, which in turn can encourage pollinators rather than cause them harm.
Until next week, stay savvy.
Brander, Matthew. “Greenhouse Gases, CO2, CO2e, and Carbon: What Do All These Terms Mean?” Ecometrica, 4 Dec. 2020, ecometrica.com/greenhouse-gases-co2-co2e-and-carbon-what-do-all-these-terms-mean/.
Engel, Hallie. “Negative & Positive Effects of Pesticides & Fertilizer.” Home Guides , SF Gate, 17 Nov. 2020, homeguides.sfgate.com/negative-positive-effects-pesticides-fertilizer-38216.html.
Son, Jiahn. “Lawn Maintenance and Climate Change - PSCI.” Princeton University, The Trustees of Princeton University, 12 May 2020, psci.princeton.edu/tips/2020/5/11/law-maintenance-and-climate-change.
“The History of Lawns.” Planet Natural, Planet Natural Research Center, 5 May 2018, www.planetnatural.com/organic-lawn-care-101/history/.