sealPurdue News

August 1, 1997

It's easy to reduce chemical exposure on golf courses, expert says

WEST LAFAYETTE, Ind. -- To most golfers, chemical use by the local golf course is one method to keep the grass green and the course in good playing condition. To others, it appears to be a threat to the environment -- or, even worse, to their own health.

Not to worry, says Clark Throssell, professor of agronomy at Purdue University and co-director of Purdue's Turfgrass Research and Diagnostic Center. He says golf courses are environmentally friendly, and golfers who are concerned about contact with the chemicals can take a few simple precautions to reduce exposure.

According to Throssell, a large amount of research in the past two to three years on the risk of golf course pesticides should allay the fears of concerned golfers. "As we take another look at these pesticides, overall we're finding that they provide almost no risk for casual exposure to levels that would be of any concern," he says.

According to Throssell, most pesticides are applied wet, and if they dry before coming into contact with people, they will not easily come off the vegetation.

"Research has shown that once the pesticide dries on the leaf of the turf grass plant, you really can't just casually brush it off," Throssell says. "To get any pesticide residue at all you have to take a rough cloth and vigorously rub the grass leaf. Obviously, no one out playing golf is going to do that in the course of a round."

Other research projects, some of which were conducted at Purdue, have shown that many pesticides are caught by the thatch before they reach the soil, and well before they would have the opportunity to enter the ground water.

"There's a body of research that shows that pesticides are either broken down by microbes in the thatch layer and soil or retained in the soil, which acts as a filter. In most cases pesticides are not prone to leaching, and runoff occurs only under extreme conditions," Throssell says.

According to Throssell, one good way to reduce exposure to pesticides is to not pressure the golf course personnel to allow golfers to play through areas recently treated with pesticides. "Many people don't realize it, but there are two main professionals at every golf course, the golf course superintendent and the head golf pro," Throssell says. "These individuals and their staffs work together to schedule pesticide applications so that there is minimal interference with golfers.

"The best solution is for golfers to be a bit more understanding when the course maintenance causes a minor interference with their round of golf."

Likewise, the golfer who complains about the stray dandelion or patch of poor turf may pressure the course superintendent to overuse chemicals. Throssell suggests that golfers adapt to courses that are less than perfect. "We should get used to playing on British-style courses where a few weeds and some brown spots are just considered part of the game," he says.

Another way to reduce inadvertent chemical exposure is to ask the golf pro and superintendent to use practices that reduce exposure. "This could be as simple as asking the course to post signs at the first tee explaining what pesticides have been applied that day and when -- many courses already do this," Throssell says. "Courses also can use equipment such as spray shrouds that prevent pesticide drift caused by the wind. They are more likely to do that if they know that pesticide exposure is a concern to their customers."

For those who are concerned about exposure to pesticides and chemical fertilizers and may want to restrict their exposure, Throssell has these additional tips:

Source: Clark Throssell, (765) 494-4785
Writer: Steve Tally, (765) 494-9809; e-mail,
Purdue News Service: (765) 494-2096; e-mail,

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