American lawns are a monocultures that are not sustainable. Learn why our lawns aren't as green as we think.
An Oversimplified History of Lawns
The number one irrigated crop in America is turf grass. In other words, our lawns consume more water than any other crop in the United States - more than corn, soy beans, cotton, and all other commercially-farmed plants in the nation. What's more? Most of our potable water (drinking water) goes to water a plant that isn't indigenous to this country AND to a plant that we can't eat. In fact, Americans spend less and less time outside as a whole, and even less time in front yards then ever before. And if that's not enough, the Environmental Protection Agency estimates that at least half of the water we're using on this tiny and tedious plant is actually runoff - meaning that that the water ends up in our sewers, along with all the chemicals we use to keep it green.
This green stuff we obsess over from spring to fall: spending weekends mowing, weeding, trimming, fertilizing, and watering in order to keep our neighbors and Home Owners Associations (HOA) happy has long been a status symbol. The practice of fawning over a well-manicured lawn has been synonymous with success and status among the French and English since the late middle ages. Grown for its ease in care and value to livestock, it soon spread across Europe and eventually to the New World. Today, we work 40+ hours a week, volunteer at our neighborhood schools and churches, buy organic produce when we can, and we spend weekends making sure our front lawns (and sometimes back) look neat and thick. But lawns, whether they comprise clover, Fescue, Bermuda, Bahia, or any other type of commercially-available ground turf for the urban landscape (around homes, parks, buildings and shopping centers, are literally killing us.
To understand why we're so obsessed with this green stuff, we have to first understand its origins.
Since the 16th century in England and France, lawns have been a status symbol.
Since the 16th century in England and France, lawns have been a status symbol for the wealthy. Grown for large herds of livestock and favored for its low-growing habit for enhanced visibility around castles and Tudors, this type of low shorn ground cover became the preferred livestock crop. Medieval times gave way to oceanic trade, providing Europe with new animals and new crops (Africa, India, and Asia), which in turn contributed to more advanced materials and techniques in farming. And while livestock did help to maintain these lower-growing grasses, outlying areas required maintenance that could only be provided by human labor - a cost only few could afford. By the 18th century, tightly-clipped lawns and elaborately clipped hedges became gathering places and recreational spaces for the wealthy. Still, much of European lawns did not require a great deal of irrigation considering the large amount of rainfall it receives.
The arrival of Europeans in the New World required the import of livestock to support growing communities, yet the land did not have the same lush pastures that dominated England. Soon, colonists were encouraged to bring over this "superior" grass seed for livestock since our native grasses consisted largely of straw and marsh grass. Kentucky Bluegrass and Bermuda Grass became the preferred livestock crop. But it wasn't until after WWII, when low housing costs and mass-produced tract homes sprouted modern suburbia, that our obsession with the perfectly manicured lawn really took off. To this day, Kentucky Bluegrass is the most desired and grown lawn in America. In 2005, NASA completed a study showing that lawns cover more than 31 million acres of American soil. That's roughly the size of the state of Mississippi.
Why This Green Stuff Isn't So Green After All
Americans love the look of a large, well manicured lawn. We play sports on them, picnic on them, and our children tiptoe barefoot through them. And let's be honest - there's nothing quite so satisfying as the smell of freshly cut grass on a warm summer morning. So why are our lawns so bad for us? In short, the problem stems from the practice of monoculture crops. Today, roughly one third of the United States is dedicated to single-crop vegetation, with turf grass leading the pack. In other words, one third of this native land has been cultivated into plants that our soil, native pollinators, and water usage were never meant to support. This puts a great deal of stress on our environment as we overuse water, deplete the soil, use pesticides, and use non-renewable energy to maintain them.
One third of the United States has been cultivated into plants that our soil, native pollinators, and water usage were never meant to support.
The Culture of Monocultures
Monocultures are any large plot of land that has been cultivated with a single crop. These single crops are most often understood to be farmed crops such as food for mass consumption for humans and animals (think of the miles and miles of corn, soy, and alfalfa fields throughout the mid-west. These crops are highly profitable and have helped feed our ever-expanding populations (including the animals we eat). Such crops are found around the globe and can be cultivated for longer shelf life and disease resistance, and thus can be shipped in mass quantities across the globe. And while we are currently using 50 percent of the earth's vegetative land for farming now, we'll be facing a 56 percent shortage of food for the estimated 10 billion people on earth by 2050. Monoculture crops are feeding the world. In this sense, the word "Monoculture" can be, on paper, a good thing. But what are the downfalls of this type of crop, and where do our American lawns fit into the equation?
1. Pesticides. Single-grown crops share the same diseases. In fact, vegetation-destroying pests thrive in monocultures. The more single plants there are in a given area, the more pests multiply, creating a non-sustainable ecosystem. Heavy use of pesticides (the stuff that kills bugs and unwanted weeds and fungus) are thus sprayed over large areas to counter the effects of single-crop areas. These pesticides find their way into our water, air, and soil - and most definitely find their way back into our bodies. Since agriculture is the largest user of pesticides, it is likely that much of the pesticide residue found in the environment originated from agriculture. However, a significant--but unknown--portion of the pesticide residue originates from non-agricultural sources. Non-agricultural uses include: home, lawn, and garden use, industrial use, pest control in forestry, weed control along roadsides, ditches, railways, and rights-of-way, pest control by municipalities and local governments, golf courses, and the military. To learn more, visit the US Geological Survey's site here.
According to the USGS, approximately half of the US population gets their drinking water from groundwater - where the risk of pesticide contamination is the greatest. Groundwater contamination is about half of the US population gets their drinking water from groundwater sources - especially those in rural areas. As in Parker, CO drinking water is sourced through a combination of surface water and (mainly) ancient aquifers. Studies now show that pesticides can reach such aquifers through a variety of methods, including through surface water runoff that contain pesticides. And while much of these contaminants come from commercial land, we must also recognize that, as stated earlier, our number one crop in America is turf grass and 50 percent the water used to irrigate these lawns end up back in our drinking water through groundwater seepage and runoff that flows back into our streams and rivers.
2. Carbon Monoxide. According to the EPA, gas powered lawn mowers run for 30 minutes create the same amount of pollution as a car driving from Pueblo to Greeley (177 miles). It is also estimated that lawn mowing uses 300 million gallons of gas and takes about 1 billion hours annually. Extensive evidence exists on the adverse health effects of exhaust emissions and other fine particulates which include cardiovascular disease, stroke, respiratory disease, cancer, neurological conditions, premature death, and effects on prenatal development. The New York Times reported, "In 2011, Edmunds, the car reviewer, compared a two-stroke-engine leaf blower with a Ford F-150 Raptor pickup truck, finding that a half-hour of yardwork produced the same amount of hydrocarbon emissions as a 3,887-mile drive in the truck. In other words: Blow leaves from your lawn, or drive from Maplewood to Juneau, Alaska. Your choice." In an era when we are looking to significantly decrease our emissions from transportation and energy use, it stands to reason we must also look at the serious impact our lawn maintenance practices have on our earth.
It is estimated that lawn mowing uses 300 million gallons of gas and takes about 1 billion hours annually.
Suburban homes have a wide range of land dedicated to turf grass. Some houses in more rural areas have very large lots and some, in more urban settings or in areas that pack larger homes into smaller lots, have smaller patches of areas for lawns. The latter is the case for my family, and we switched to a push mower when we moved into this home 12 years ago. Our neighbors would first scoff at our little manual mower as it bounced over lumps in the lawn and required a few more passes to get a clean cut. The perception is that these manual mowers are hard work to push. And while their predecessors did have some drawbacks, newer models are much, much easier to maneuver. And though we have reduced our grass turf area significantly through pollinator and native plants, we now edge our lawn with a battery-powered trimmer (which poses its own issues in energy consumption) or manual shears, and we use a good-old reliable rake to clean up debris for compost. Is it more work? A little bit. But if you consider the amount we are reducing our share of carbon emissions, a little elbow grease seems worth it.
3. Water. Lawns require one inch of water per week. In most places in the United States, rainfall isn't enough. Denver alone averages only a fraction of that per week (0.32 inches per week) and the US averages only 0.73 inches per week. According to the National Weather Service, Colorado received a total of 8.53 inches of precipitation for the entire year of 2018, claiming it was the 6th driest and and 20th hottest (tied) on record. Don't
forget - Colorado is really a desert - or high plains state. Our water, though we are often referred to as the "headwaters state" because of the many sources of water that begin here from the Rocky Mountains, is shared too - this means what we receive in moisture does not belong solely to us. As the seventh driest state in America, we're sharing our resources to six other states (The Colorado River Compact signed in 1922). According to Colorado State University, 86 percent of the water we do have goes directly to agriculture. If a 25-by 40-foot (1,000-square-foot) lawn requires 625 gallons of water weekly (or approximately 10,000 gallons of water each summer), it stands to reason we're using water we just don't have to grow a crop that does not grow well in America and that we don't even use. And remember - half of the water we use on our lawns is runoff.
The Average lawn requires 626 gallons of water weekly. In a drought-stricken part of the country, that's a lot of water used for a crop we don't eat.
4. Fertilizers. SafeLawns.org estimates that Americans spend $5.25 billion on petroleum-based lawn fertilizers and $700 million on lawn pesticides annually. That's a lot of "green." Let's first take a look at the most valuable nutrient to assist in plant growth. The good news is that nitrogen is abundant in the air. The bad news is that atmospheric nitrogen (N2) forms tight bonds making it difficult for plants to use. Before WWII, farmers knew that they could use animal waste and plant compost to enrich the soil to feed crops.
But those crops fed a much smaller population, and most farmers at the time grew more than one crop at a time. Crop rotation helped farmers replenish nutrients (legumes are a known nitrogen-fixing plant) back into the soil. Since crops were smaller and more diverse, fertilization occurred naturally.
That is until a German chemist named Fritz Haber developed a method in 1909 to pull nitrogen from the air and process it into nitrate (plant-viable nitrogen). The Haber process produces amonia from methane gas and molecular nitrogen. Wilhelm Ostwald developed the process to convert the amonia into nitric acid. Still, these processes were expensive and energy-intensive and could not produce large amounts at a time. Though this process did not go to waste. This process paved the way to make explosives and weapons of mass destruction in WWII, specifically chlorine gas and munitions. The method spread across the world and by the end of the war the United States took the lead in nitrogen processing for weapons. Once the war was over, these processing plants turned to fertilizer production in order to feed the growing populations around the world. To this day, the United States consumes 12 percent of global nitrogen-fertilizer production. But if nitrogen is required for plant growth, how could it be bad?
Granular and liquid fertilizer is great. In fact, commercial fertilizers are what keep us alive. But we need to consider the amount of fertilizer we are using, the way we are applying it, and where it actually ends up. Oh, and in case you were wondering, fertilizer production is increasingly using the process of fracking. But that's a whole other story.
The availability and low cost of nitrogen-based fertilizers have made it easier than ever for the average American homeowner to achieve that lush green carpet every neighbor envies. But like most things of convenience these days, with ease comes inconsistencies and misuse. The EPA estimates that 40 to 60 percent of the nitrogen from lawn fertilizer ends up in surface and groundwater.
When we overuse fertilizers, excess nitrogen (especially when applied without careful consideration to time of year, time of day, and proper application) ends up in our water. Chemical fertilizers have been associated with diseases many human diseases - especially Cancer. The United States Geological Survey measured private wells across the nation for 12 years, concluding that nine percent of samples exceeded the regulatory limits for nitrate. The International Agency for Research on Cancer (IARC) concluded that “ingested nitrate or nitrite under conditions that result in endogenous formation of N-nitroso compounds is probably carcinogenic to humans.” And while 9 percent seems like a low risk, we must take a look into the future and account for the impending population boom. How will the use of chemical fertilizers affect us in the future?
Ecosystems. We're talking about all the critters that live on this earth that rely on plant diversity for survival - especially pollinators. While we are reading countless articles about honeybee colony collapse disorder, the real fear (as any entomologist will tell you) is the loss of our native bees. Honeybees are not native to the United States. These bees were brought over from Europe to pollinate
and provide honey for colonists. These are the social bees that are suffering most from colony collapse, as they are now used as a commodity around the world. Use of pesticides have been linked to their demise. But what is lesser known, and perhaps more of a concern, is the diminishing numbers of native bees and pollinators that we rely on as well. You see, honeybees are not exactly the most efficient pollinators. They have little "baskets" on their legs that are specifically designed to collect and carry pollen back to the hive to feed the colony. This is particularly efficient - if you are a honey bee. But plants require pollination from one flower to the next in order to reproduce (you can't get an apple to grow on an apple tree if the blossoms are not pollinated). If honey bees are carrying most of their pollen home, very little of the pollen gets transferred to other flowers. In essence, honey bees are good at making honey - they are not very good at sexing up crops. The
United States has more than 4.000 native bees, 946 of which are native to Colorado. These are the bees that pollinate plants, along with butterflies, moths, birds, and other insects. However, the heavy use of pesticides and chemical fertilizers are having a negative impact on our little life-giving friends. Pennsylvania State University conducted a
study analyzing 1300 pollen samples and
found that 91 percent were contaminated with pesticides averaging six pesticides per pollen sample (31 pesticides in a single pollen sample and 39 pesticides in a single wax sample).
With the increasing use of monocultures in the United States, heavy use of pesticides and chemicals are required to keep crops thriving. And with the steady decline and
expense of honey bees, we're becoming more and more dependent on wild bees to maintain the status quo, but many of our native bees (and other pollinators) have a biological predisposition to native plants specific to certain regions and climates. And here is where it gets bad. Native plants require native pollinators and other animals. With significant habitat loss and spread of monoculture crops, these plants are disappearing and so are the pollinators. And it doesn't end there. Remember the movie The Lion King, when Mufasa tells Simba about the circle of life? Without the plants we don't have animals, and yes, that includes humans.
So What Now?
With turf grass being the largest monoculture crop in the United States, we must consider the front lawn public enemy number one. There are countless factors in climate change, and only a handful of them are within our immediate control. You can stop using single-use plastics. You can use mass transit to get to and from work. You can even boycott large corporations that use non-renewable energy or pollute the environment. But one of the most immediate and gratifying changes you can make right now is to contact your HOA and tear out your front lawn and replace it with beautiful, life-giving plants. A diverse ecosystem on each suburban block can make an enormous difference in our environment and the future of humanity.