Delia says she enjoys playing on her pesticide-free lawn, which displays a healthy crop of clover. What"s so bad about clover, anyway?© Jim Motavalli
In the postwar years, the makers of 2,4-D looked for non-military markets. The herbicide was promoted to homeowners and farmers by the media, with articles in 1945 in Country Gentleman, Better Homes and Gardens and Reader’s Digest. Scientific journals reported the effectiveness of herbicides. Advertising targeted suburbanites, who were using government-guaranteed mortgages to move out of cities.
The makers of "Weedone" and "Weed-B-Gone" were not just selling a product; they were selling the ideal of suburban paradise blanketed with lush, unblemished greenery. The late John Brinckerhoff Jackson, an author and lecturer on the geography of everyday places, said that suburbs were essentially based on farm villages, in which conformity is high in building style, incomes and families. Suburbs reflect Jeffersonian attitudes of local control, isolationism and self reliance.
Yale University Press" Redesigning the American Lawn reviews the history of the lawn as an 18th century European concept. Open farmyards gradually gave way to walled gardens, packed with food plants and flowers. Nature was controlled and restrained, often with the aid of grazing sheep. Large, elegant private lawns were originally only for the wealthy, while the entire community could enjoy the open "lawn" or "green" in town. Early America was a wild place, and the comfort of a controlled reality close to home was appealing.
By the mid 1800s, American city dwellers first began to move out of crowded metropolises, and suburban landscapes evolved that appeared "natural" but were intensely controlled. Lawnmowers appeared in the 1830s, and made carpets of greenery more accessible. In fact, without the lawnmower the modern lawn would be a near impossibility.
Although the popularity of specific varieties of plants and of such accents as terraces and fences varied over the years, the green, crew-cut, biologically and aesthetically monotonous lawn began to dominate the landscape. Frank J. Scott wrote in The Art of Beautifying Suburban Home Grounds in 1870, "A smooth, closely shaven surface of green is by far the most essential element of beauty on the grounds of a suburban house." Such a lawn strives not to stand out, but to fit in. It does not challenge the neighbors" ideals, and it does not set a home apart from others unless it looks bad. When "perfect lawns" became easier to maintain, more people adopted them, putting pressure on the neighbors to do their part to build the community’s uninterrupted carpet of green.
This ideal burgeoned in the 1940s, when the middle class had the means (cheap housing) and desire to begin a new life, complete with their own lawns. As retail analyst Victor Lebow put it in those halcyon days, "Our enormously productive economy
demands that we make consumption our way of life, that we convert the buying and use of goods into rituals, that we seek our spiritual satisfaction, our ego satisfaction, in consumption." In other words, people were asked to do their part for the economy, and an orgy of pent-up consumerism replaced the sacrifice of the war years. Through the miracle of modern chemistry, homeowners could easily kill their weeds with off-the-shelf products, never getting dirty or shedding a bead of sweat.
Don Gordon, professor emeritus of biology at Minnesota State University and syndicated columnist on horticulture and the environment, says pesticide use is not a free lunch. "For the past half century synthetic pesticides [and herbicides] have been the quick-fix elixir for our pest problems, but let’s not forget they are a Faustian bargain," he says. "These chemicals have poisoned humans and other species, contaminated our water supplies, reduced biodiversity, increased pest resistance, interfered with natural pest control and are directly responsible for a host of other environmental problems."
The question "Are herbicides safe?" is not easy to answer. First, we don’t have a lot of standardized, long-term safety data on these chemicals, probably because government agencies tend not to act until a direct causal connection between human health and chemical exposure is made. <
Thirty years ago, Doris Goodwin was doing something she loved to do: working in her yard. She owned three acres of wooded land, gardens and lawn in New York’s Hudson Valley, which sometimes proved a challenge to maintain. For years, she had faithfully applied a cocktail of herbicides and pesticides on trouble spots, always being careful to follow directions and use safety equipment. But this time, something went wrong. Goodwin accidentally inhaled a toxic dose of herbicides, and it immediately felled her.
Goodwin was significantly impaired for about six months, and it took about a year for her to return to some semblance of normalcy. After the acute poisoning, Goodwin developed asthma, and spent the remaining 25 years of her life with headaches, decreased energy and a newfound sensitivity to a wide range of chemicals she’d used around the home for years. She was no longer able to tolerate conventional herbicides because of adverse reactions, and was forced to switch to natural lawn techniques for the rest of her life.
Chemicals that have known toxic or carcinogenic effects are still on the market, as evidence continues to mount and long-term studies proceed. "There simply has not been adequate testing to show the true dangers of herbicides and pesticides," argues Matthew Wilson, director of the New England-based Toxics Action Center. Wilson points to the recent Environmental Protection Agency (EPA) ban of the popular insecticide diazinon as an example of how slow the regulatory process can be. "Everyone used diazinon for 20 or 25 years, but it wasn’t until testing in the late 1990s showed it to be harmful that it got banned," he says.
Still, if we had a choice we might err on the side of caution and the so-called precautionary principle, which says that chemicals should not be used until they’ve been thoroughly studied, critics argue (see "The European Dream," features, March/April 2005). "The pesticide industry has significant influence on government," says Wilson.
Herbicide makers argue that the majority of their products applied to grass stays there. But what about the rest of it? Some gets washed into ground and surface waters, threatening natural systems. You track some into the house on your shoes, according to a study by the National Exposure Research Laboratory and the EPA. Kids, pets and wildlife can’t read those little flags that warn, "stay off until dry," and the warnings may in any case be inadequate. "Twenty-four hours of drying time is no assurance," says Wilson, "because the time it takes lawn chemicals to break down varies greatly. Some stay for a long time."
Removing shoes inside the house helps, but there is still the problem of dust. Herbicides become aerosolized, and some particles are small enough (less than 10 microns, the "deadly" PM10s) to infiltrate the lungs. Herbicide dust can enter the house anywhere air can. Plus, these chemicals tend to break down more slowly indoors, since they are exposed to less sunlight and water. The particles lodge in carpets and fabrics, so homeowners end up breathing, eating and absorbing herbicides through their skin as they relax at home. "Tests find DDT dust in people’s homes, even though the chemical had been banned 30 years ago," says Wilson.
Further, as Dr. Philip Landrigan, director of Mount Sinai School of Medicine’s Center for Children’s Health and the Environment, explains, "Kids" behavior puts them at greater risk—they are on the floor and constantly have their hands in their mouths." While the amount of lawn chemicals one might take in daily from the home is well below the level the EPA has determined to be risky, would you willingly eat or apply herbicide to your skin (or your children’s skin) on a daily basis? What about people who are especially sensitive?
The herbicide 2,4-D kills plants by overdosing them with growth hormones in a process that is not precisely understood. What happens when humans are exposed to this chemical? Research in Sweden in 1981 found the occurrence of lymphomas (a variety of soft-tissue cancer) to be five times higher than normal in people exposed to 2,4-D-type herbicides. A study of Kansas farmers who applied or prepared 2,4-D for more than 20 days per year identified a non-Hodgkin’s lymphoma incidence six times higher than that of the average population. A study in Canada found risks of this cancer increased along with increased exposure to herbicides.
A study by the National Cancer Institute in Iowa and Minnesota did not find significantly elevated risk of cancers in relation to any specific herbicide. But farmers overall tend to experience higher-than-usual occurrences of many types of cancer. Because the farmers in the Midwestern study were also exposed to pesticides, gas fumes, fertilizers, solvents and fungicides, the researchers had difficulty isolating variables.
According to the National Cancer Institute, "It takes many years for the development of a tumor and even more years until the detection of a tumor and its spread to other parts of the body. People exposed to carcinogens from smoking cigarettes, for example, generally do not develop detectable cancer for 20 to 30 years." This is not necessarily true for all cancers, but it is a common trend. Therefore, studying people with recent exposure to herbicides may not detect carcinogenicity.
For greater clarity, scientists are examining a population that experiences regular, extensive exposure to herbicides over long periods of time—golf course superintendents. Studies at the University of Iowa showed a 23 percent increase in non-Hodgkin’s lymphoma, 29 percent increase in prostate cancer, 17 percent increase in cancer of the large intestine, and 20 percent increase in brain and nervous system cancers.
On the other hand, preliminary studies of professional herbicide applicators (Journal of Environmental Medicine, 1995) showed no increase in cancers. This study did not allow many years to lapse after exposure, however. Many people held the job for less than one year.
Another interesting piece of the herbicide puzzle is that by merely looking for incidences of cancer, we may be missing part of the picture. In 1996 the Journal of Occupational Environmental Medicine reported that farmers who had been exposed to 2,4-D-type herbicides had significantly reduced numbers of immune response cells in their blood. "Further studies should clarify whether the immunological changes found may have health implications," conclude the researchers. In many cases, suppression of the immune system is known to weaken its ability to fight cancer.
What about the low doses of exposure that an average homeowner experiences over time? The short answer is that we simply don’t know yet. Short-term effects of 2,4-D exposure can include cough, dizziness, nausea and loss of muscle coordination. This may be as much of a deterrent for some as cancer risks.
Research in pet dogs represents a population of smaller stature, and an accelerated life cycle compared to humans. Also, it takes more time for an herbicide to clear a dog’s system. A 1991 study in the Journal of the National Cancer Institute found dogs were twice as likely to develop malignant lymphoma when herbicides were applied four or more times per year, and dogs diagnosed with lymphoma were 30 percent more likely to come from homes using herbicides.
eeds with genetic susceptibility to bladder cancer living with herbicide-treated lawns displayed four to seven times the risk of developing the condition compared to those living with untreated lawns, according to a study published in the Journal of the American Veterinary Medical Association. Herbicides have been found in the urine of dogs that neither live on treated lawns nor run loose. Herbicides do not stay where you put them.
What About Roundup and ChemLawn?
The world’s top-selling herbicide, glyphosate (the primary chemical in Monsanto’s Roundup), is not selective. It kills broadleaf weeds and grasses by—many scientists hypothesize—blocking an enzyme plants need to make certain proteins. This enzyme is part of a metabolic pathway not shared by mammals, so ostensibly they will not be harmed. "Glyphosate is a herbicide that is constantly lauded as benign," explains the Sierra Club of Canada.
But glyphosate can cause skin and eye irritation. Some individuals experience respiratory distress, fatigue and headaches after application. There have been reports of neurological problems developing after exposure as well as increased rates of miscarriage, adds the Sierra Club. Glyphosate is also known to cause liver and digestive system abnormalities in laboratory animals. It may also disrupt certain hormones.
Roundup at one time was advertised as being biodegradable, environmentally friendly and no more dangerous than table salt. Beginning in 1991, the New York State Attorney General complained about Monsanto’s advertising of the chemical. The matter was settled out of court and the advertising was toned down.
Herbicide labels usually list from 80 to 90 percent of the volume as "inert" ingredients. But Holly Carver points out in the Journal of Pesticide Reform, "At least 382 chemicals, 15 percent of the whole inert list [in the EPA’s chemical ingredient database] are or were registered as active ingredients [and] can be used legally in pesticide products." Manufacturers must list only one inert ingredient that is "active" and considered of toxicological concern, even if the product contains more than one. "There is minimal testing on the possible synergistic effects of all these inert ingredients, or of combinations of herbicides and other chemicals," says Wilson of the Toxics Action Center. According to the Sierra Club of Canada, "The toxicity of glyphosate alone is much less than the toxicity of commercial glyphosate used by consumers, due to the so-called "inert" ingredients."
Herbicides of almost all kinds are found in surface water, groundwater and even treated drinking water. Most herbicides are toxic (in varying degrees) to various bird and fish species, particularly in combination with other chemicals. Glyphosate is toxic to fish, earthworms and beneficial insects, and has recently been shown to cause significant mortality in tadpoles. When you expose yourself by choice, you expose the rest of the environment without permission.
What about weed resistance? It is already happening around the world, according to the "International Survey of Herbicide Resistant Weeds," an international collaboration of academics and representatives of the herbicide industry. Since the 1950s, more than 30 species have developed resistance to 2,4-D and glyphosate. Almost 200 weed species in the world have resistance to some form of herbicide.
People think herbicides will give them a neat, weedless lawn, needing only an occasional mow and some sprinkler action. TruGreen ChemLawn, the nation’s largest commercial lawn care service, asserts: "We want to assure you that safety to our employees, our customers, their children, their pets and the environment is the most important criterion in our selection and use of our lawn care products. We also want you to have complete information about the products we use and their toxicity."
But Wilson argues, "People think they are signing up for a green lawn, but they don’t know they are signing up for dangerous chemicals that threaten their kids and their pets." The Toxics Action Center has launched a boycott of ChemLawn, and claims the company is "not upfront about the dangers." When E called a local branch of the company and asked for customer information on product toxicity and an ingredient list, we were told it wasn’t available.
According to Chemlawn, "Taking care of your landscape helps take care of the environment." The company argues that lawns purify and conserve water, maintain air quality, decrease allergens, trap dust, moderate temperature and noise, generate oxygen, slow the spread of fire, build topsoil and reduce erosion. However, critics point out that all those benefits result from natural processes, not applied chemicals. TruGreen also argues, "The toxic potential of any substance is a function of dose or concentration. The spray applications most commonly made by TruGreen ChemLawn are dilute aqueous solutions of fertilizer and pesticides consisting of approximately 92 percent water, 7.5 percent fertilizer and 0.5 percent or less of pesticide. However, approximately 50 percent of our applications consist of dry granular formulations of lawn care products that are similar to those available at retail stores." Are we to assume everything in retail stores is safe? Is dilution the solution to pollution?
What are the Alternatives?
People don’t tend to think too much about preventing problems—we react to them. Herbicides are a reaction to a preventable problem. Almost any book about lawns, old or new, promotes keeping a lawn healthy as the best way to prevent weeds. Grasses that are healthy grow densely and shade or out-compete weeds.
"From our perspective it is not worth the risk to our water, children and pets [to use conventional herbicides]," says Wilson. The advocacy group Beyond Pesticides points out that passing local ordinances restricting the use of herbicides and pesticides is very difficult, because "41 states, whose legislatures have been subject to chemical industry lobbying, have acted to preempt local authority to regulate pesticides." However, there are many ways people can tend beautiful, healthy, functional lawns without a deluge of industrial chemicals.
"A healthy lawn occasionally requires fertilizer. Potassium, nitrogen and phosphorus are often recommended, but use care with phosphorus because surface runoff leads to aggressive overgrowth of algae. Too much nitrogen will give you a lawn full of thatch. You can have your soil tested for nutrient deficiencies through a local nursery or agricultural extension office. Organic fertilizers combine various nutrients and are less likely to "burn" the grass. Fertilizer alone can get rid of some weeds.
"Not much off the top, please. Cutting grass too short forces it to grow faster to get enough leaf surface, robbing energy from the roots. Longer grass is healthier, keeps moisture from evaporating and shades weed seedlings. Most lawn grasses can be cut at three to four inches, especially during hot weather.
"Water the lawn, not the weeds. Inadequate moisture weakens grass, giving drought-tolerant weeds a chance to get established. Watering too often encourages shallow roots, which can’t reach deep into the soil for moisture during dry spells.
nt the right kind of grass for your area. When you buy seed, its tolerance for trampling, sun or shade is often listed on the bag. It is often mixed with quick-growing annual types for fast cover. With sod your choices are more limited.
"Soil pH can hinder the health of a lawn. Inexpensive soil pH testing kits can be found at some nurseries and garden centers, although a professional test is more accurate. If the pH is too high or too low, weeds have the advantage.
"Manual removal. That’s right, pull weeds! Or better yet, if you have kids (or know neighbor kids or scout troops) make it worth their while to do it for you. Set a good example. Short of spraying herbicides or burning your lawn (not likely to be legal or socially acceptable if you live in town) you have to either pull them or live with them. Dandelions, crabgrass and plantains can be removed with a paring knife; a triangular hoe can be used while standing. Products like the "Weed Hound," a long-handled device, remove weeds, roots and all. If you don’t get the roots, you"ll be pulling the same weed several times.
"What about clover? If you have clover you probably have a nitrogen-poor soil, and consistent fertilizing can help over time. But clover is not so bad to have. Clover seed used to be mixed with grass seed for healthy, dense cover and as "built-in" fertilizer.
"Stop weed seeds from sprouting. A product called corn gluten meal, a by-product of corn syrup manufacturing, can be purchased from organic lawn care companies like Gardens Alive. Corn gluten meal won’t get rid of what is already there, but it will keep new weeds from sprouting. If you have dogs, don’t be surprised if they want to eat it. Corn gluten meal is a common pet food ingredient.
"Hire a natural, organic or "green" lawn care service. These new businesses are popping up around the country, and can be a great way to transform your lawn into a natural paradise with minimal effort.
"There is room for compromise. If you have a lawn full of weeds and cannot pull them yourself, you may want to convert to low-toxicity management. Perhaps you could spot spray, then switch to all "organic" methods over time. Change is challenging and it’s better to do what you can reasonably handle than overwhelm yourself and go back to the chemicals.
"Who needs a lawn, anyway? Some homeowners are simply giving up on green lawns and planting fast-spreading, no-maintenance native covers instead—or simply letting their acreage grow wild (a solution that may run afoul of local zoning ordinances). Another solution is a rock garden or woodland.In 50 years, herbicides have become so ingrained in our culture that we may not think other methods are effective. Trading the ease of applying herbicide for hand pulling weeds and improving your lawn’s health takes effort, especially at first. But one day the "perfect lawn" may be redefined as one that is pleasing to look at and safe to live with. An ounce of prevention is worth a pound of herbicide.
WENDY MUNSON SCULLIN, an Iowa-based freelance writer, also studies native plants and horticulture.