EDUCATION SPOTLIGHT

Cornell EIQ Calculator Aids Pesticide Assessment Efforts

Among the myriad of tools today’s superintendents employ to keep ahead of nature’s many golf course maintenance challenges, Cornell University College of Agriculture and Lifescience’s Environmental Impact Quotient (EIQ) Calculator ranks up there in the “indispensable” category.

In fact, the free online tool, which measure the risk of a pesticide application using five simple parameters, has become invaluable for Audubon International’s certification specialists as they help member courses chart healthier courses for their unique local ecosystems.

“It was invented by a Cornell researcher back in the nineties,” says Carl Schimenti, Urban

Environmental Scientist in Cornell’s School of Integrative Plan Sciences. “His goal was to figure out how we can measure a pesticide by the weight — pounds of pesticide applied. There are different toxicity levels of pesticides. Some are ‘softer’ or ‘harsher’ on mammals or birds or fish or whatever. So they developed a system that incorporates those toxicity levels with exposure levels.”

The EIQ measurement model was first applied to turf in the early 2000s when Jennifer Grant, then- Director of the New York State Integrated Pest Management program, and current Audubon

International Board member, Frank Rossi, Associate Professor for turf grass science at Cornell, worked with the New York State Park system to develop ways to manage golf courses with lower pesticide risk. “They looked at the old, conventional pesticide programs, calculated the EIQ and then said, ‘Hey, what if we chose products that were less toxic, lower EIQ? Could we use those products, and would the turf be just as healthy?’”

That led a five-year study at Bethpage Green, one of five municipal golf courses at Bethpage State Park on Long Island. “They found that it worked — if you can select products that work with the same efficacy but with lower EIQ numbers, you can achieve the same exact results.” From there the state expanded the EIQ to the entire New York State Park golf system. “Every year about 15 golf courses calculate their EIQ and we look at which applications were higher or lower, and how can we reduce them. We’ve been doing that for more than two decades now.”

In 2021 Kat Welch, Audubon International’s Director of Signature Sanctuary Certification, was researching about the EIQ and reached out to Schimenti. “I had known Kat for at least five years. A lot of my extension work at Cornell is best management practice focused, which meshes well with what Audubon International does. Kat was specifically interested in using EIQ to figure out which pesticides to test for in water bodies. They want to make sure that there’s no pesticide residues in the water.”

“One component in the EIQ model is aquatic toxicity — toxicity to fish. We pulled out that specific part of the model and remade all the numbers to look at aquatic toxicity, to help Audubon International determine what Signature Sanctuary members should test for in water bodies. Instead of testing for every single product, which is expensive, we look through products and say, ‘OK, which ones have high toxicity to fish, but also, which chemicals are mobile enough? When you apply them, can they run off in a rainstorm, are they not bound to the soil? Do they get into the water?’ We’d consider high risk or medium risk, and test for everything above that level.” According to Welch, courses currently concentrate on testing those that are high risk with high leaching ability and high aquatic toxicity.

“One part of pulling [water data] out of the EIQ is the ‘surface loss’ component that considers all those factors, and that’s multiplied by the tox- icity component,” Schimenti continues. “Once you do isolate a certain chemistry and find it in a water body, you can look at having vegetated buffers — and the width of that buffer. Sometimes it’s five feet, sometimes it’s seven feet. But research shows that when you extend that buffer to 15 or 20 feet, the pesticide residues go down. So it’s first of all identifying the chemicals that are potentially toxic to aquatic organisms, then testing, then being able to adjust — choose a different chemical or employ those structural BMPs and continue testing and making improvements.”

Coupled with advances in the chemical makeup of modern pesticides since those early Bethpage tests, Cornell’s EIQ — and its application to turf science and water testing — gives Audubon International yet another powerful weapon in its stewardship arsenal.

“The EIQ, Carl and the entire team at Cornell have been a great help to our golf programs,” says Welch. “Having as many expertly created, vetted and scientifically sound testing tools as possible at our disposal helps us and our membership achieve sustainability goals with the best, most thorough data available. Keeping pesticides out of a course’s water sources is key to all of our certification efforts, and the EIQ helps make that happen in a seamless, simple yet powerful way.”

With the right information in hand, Welch and her Audubon International colleagues can widen their lens to take a look at every potential pesticide available, including low-impact organic applications.

“A lot of traditional chemistries can be replaced by newer, reduced-risk chemistries,” Schimenti says. “Bethpage subbed out a lot of synthetic chemistries for biological organisms — basically living things that you apply that help control fungus. The turf industry was, ‘They won’t really work, they’re not gonna really replace that other chemistry.’ But the Bethpage study found that you absolutely can do that. You just must be strategic when you use them. Those products work well when disease pressure is low, in the spring or the fall when there might be little fungus pressure. You save higher EIQ traditional chemistries for when it’s really hot and humid out. There’s a time and place to use high EIQ products with certain chemistries.

“In most cases, you’ve got options. You’ve got more tools in the toolbox. That’s when the EIQ is a nice decision support tool. There’s data on how well [a pesticide] works against a specific pest. ‘Okay, let’s look at all the ones that are really effective, and choose one with the lowest EIQ.’”

What about out West, or in drier climates? Does the EIQ point to the efficacy of employing different pesticides than a course in the Northeast or Southeast might?

“The spectrum of chemical use is much different,” Schimenti says. We are currently working on a paper with data from Northeast courses, Midwest golf courses, Southeast, Northwest and Southwest. [In New York state] there’s more fungicides used. In other areas of the country, there’s more herbicides, especially Pacific Northwest where it’s cool and wet. For half the season they’re trying to control poa annua so there’s a lot of herbicides. Insecticides and Nematicide are used a lot more in the Southeast. So it’s interesting to look at. We do annual calculations of EIQ and toxicity and risk, and they’re about even across the United States, but definitely a different spectrum