[Rachel's Introduction: "As to how much exposure or how much of a risk that is, it's still ill-defined. It comes down to the precautionary principle
. If we don't know the risks of these [lawn] chemicals, then we should take precautions and not use them, especially because it's an aesthetic use."]
There is one space around the house which is simultaneously green yet perhaps not green. It's your lawn, that stretch of green which may not be environmentally green if it receives heavy treatments of weed- killers, insecticides, fertilizers and other chemical aids.
Many people cut what grows, but those who clip and manicure or know someone who does may wonder whether the lawn can be an environmentally friendly decoration. It can, and although the movement to more natural lawn maintenance has been around for 10 to 15 years, only recently is it of real interest.
"All of a sudden it's exploded. Especially mothers with kids are becoming concerned with chemicals in the lawns," said Racine-area landscaper John Melby. Until this past winter when he went to a Chicago conference, he too hadn't thought much about the issue.
It was the first conference there for professional landscapers, said Kim Stone, associate director of the Safer Pest Control Project, which is based in Chicago and covers the state of Illinois. Although the group has existed since 1994 and has spoken to countless neighborhood groups, its leaders have always wanted to sponsor a conference for professionals, she said. It grew from frustration among people unable to find companies that maintain lawns organically. "A lot of people don't maintain their lawns themselves and don't know what's being used on their lawns." And although laws require companies to tell people what chemicals they use, she said, many don't.
The conference had capacity for 100 and sold out. "We did have to turn a lot of people away," Stone said.
Melby had a revelation. "I just realized that, my gosh, what I've been doing 30-some years is damaging the environment," he said. "And most of all children -- I've got grandkids now, and I worry about chemical exposure in general."
Scientific studies are building blame for household chemicals as a factor in many childhood illnesses. We know pesticides exacerbate asthma, said Dr. Claire Gervais, a family practice physician in Madison. Along with a neighbor, Gervais started what became the Healthy Lawn Team, a neighborhood network now helping communities all over the state promote the elimination of lawn chemicals.
Studies have linked pesticide use in schools with acute illness among staff and students, and have linked pesticide use at home with an increased risk of childhood leukemia. But one of the biggest issues is that in the end we don't know because these studies are difficult to do, Gervais said.
"As to how much exposure or how much of a risk that is, it's still ill-defined. It comes down to the precautionary principle. If we don't know the risks of these chemicals, then we should take precautions and not use them, especially because it's an aesthetic use."
We also need to remember the chemically sensitive, she said, about one in every one thousand people. Some become very ill or die because of pesticide exposure. "And we need to just look out for those canaries in our coal mine."
It's not only children who are at risk. So are creatures on the ground and in the water. Pesticides linger, Melby said, and after killing what humans want them to kill they may go on to kill the organisms that form the basis of the food web.
In 2003, two scientists writing in Land Use Policy noted that the popular herbicide 2,4-D is toxic to birds, fish wand insects. Between 3,300 and 4,400 tons of 2,4-D were used in the United States in 1996, according to data they found. After 10 days on the lawn, only half of the stuff has broken down.
Another popular herbicide, glyphosate, has a half-life of 47 days, and in 1996 total application in the country was between 2,200 and 3,300 tons.
Their study also noted that lawn chemicals are applied at about three times the rate of agricultural chemicals, and that while agricultural chemical use decreased by 12,189 tons from 1992 to 1997, lawn chemical use increased by 7,747 tons.
This is not to say that products labeled organic are better or safer because of that label. The term typically means unprocessed, yet some organic products used in the past were more toxic in some ways than the synthetics which displaced them, said John Stier, associate professor of environmental turf grass science at the University of Wisconsin-Extension.
He said a woman called him recently because she was concerned that corn gluten -- which prevents seed germination and provides some fertilization -- also isn't completely safe.
And ironically, he said, he found himself making the same arguments used to defend synthetic lawn chemicals, that if used properly organic products are low-risk.
"A person cannot prove a negative. I cannot prove there is no harm in corn gluten meal. I can prove that it's not likely to cause any significant harm."
All that fertilizers do for you, Melby said, is make grass greener faster in the spring. That leads to more basic questions: What should homeowners expect, and what compromises are they willing to make? "It's actually relatively easy to have a low impact lawn," Stier said.
Of course many people already have that. About half of homeowners don't do anything to their lawns, and Melby said that in the arid West and Southwest there aren't any lawns at all because the environment isn't suitable for grasses.
Organic lawn care really amounts to what has been done for hundreds of years, but it does require a change of perspective. "It's easy to do if one is willing to accept a different quality of lawn," Stier said. "You probably give up some perfection, probably have more weeds and more brown turf in the lawns. Is that really bad? We probably would not have lawns all looking the same. Is that bad?"
Some landscapers he's talked to are caught between the opposing goals of organic care and a perfect green lawn. What we really need, he said, is a national conversation on what we want.
That includes defining what we mean by environmentally friendly because, Stier said, what seems a good idea at first may have consequences that aren't. He cited El Paso, Texas, which has been buying up lawns and replacing them with rocks and native plants to reduce water usage. But in that part of the world people use air conditioners which blow air across damp fabric so they have both cooling and humidification. Putting rocks near homes increased the amount of mass absorbing and radiating heat, and that increased the need for air conditioning which increased water use.
"Do we want to be green for the sake of green, or do we want to be sustainable?" Stier said.
And again, he said, if we use the simple techniques used for hundreds of years it is easier to go green with lawns than with many other facets of our lives such as food or transportation."I think the bottom line is if people are willing to accept different quality of turf, we can be green pretty easily, and it's never left us."
Lawns have historical roots
Lawns have been around for a while and do more than make a home look pretty.
In the United States they began as means of keeping dirt out of the house, said John Stier, associate professor of environmental turf grass science at the University of Wisconsin-Extension. Before then most people had yards covered with nothing except dirt.
They also became useful for keeping nature outside because those expanses of manicured grass were not hospitable to spiders or ticks which then were less likely to enter houses. Next lawns became useful for recreation, and especially since the 1950s have been used to increase home value. Real estate studies have shown that good landscaping adds 10 to 15 percent to the resale value of a home, he said.
Today we recognize their other qualities of lawns, that they make an area cooler, hold soil to prevent erosion, filter runoff after storms, and help recharge groundwater.
The modern lawn chemical industry took hold after World War 2 as a result of two changes, Stier said. One was the advances in chemistry resulting from the war effort, and the other was the growth of suburbs brought by affluence and automobiles.
Three green things
From John Stier of the University of Wisconsin-Extension here are three steps you can take right now to start on the path to an environmentally friendly lawn.
* Mow high -- 3 to 3 � inches -- and frequently. That will be enough to keep out most weeds. Make sure your mower blade is sharp so grass is cut cleanly heals easily.
* Leave clippings on the lawn to act as fertilizer and protection for the grass.
* Plant the right grass in the right place. Kentucky blue grass, which most people have, prefers full sun and fertile, well-drained soil. It doesn't do well in the shade or in soil which is extremely wet or dry. Someone who wants a hardier grass that requires less care should plant a fine fescue. That grass will have more brown in it, won't look as neat, and it's not made for high-traffic areas.
Area landscaper John Melby recommends starting with a soil test to determine what a lawn needs. Those are easily available through the local University of Wisconsin-Extension office.
Be careful with organic fertilizers, Stier said, because many of them are high in phosphorus which most lawns don't need and which contributes to the growth of algae and weeds in rivers and lakes.