My bio states, "10 years working on a golf course prior to entering the world of research in 1989." For five of those years, I was on the crew, was an assistant for one year, and spent four years as a superintendent.
My greens management program essentially consisted of mowing and changing cups daily, topdressing every three weeks, core cultivation in the shoulder seasons, applying 4.5 pounds of nitrogen per year for growth and color, applying 6 pounds of potassium for improved wear tolerance and winter hardiness, irrigating by guess, and preventive spraying for disease.
For insect outbreaks, my arsenal included chlordane, which killed almost everything regardless of timing. For snow mold control, I applied mercury-based Calo-Clor. Both of those pesticides carried the "Danger" toxicity label, and, like most applicators of the day, I was applying them without personal protective equipment, which often resulted in a pounding headache.
Like many superintendents, I searched for less toxic options, so when a salesman informed me that Bt (Bacillus thuringiensis, a natural bacterium insecticide) had a "Caution" label, I was an easy sell. Fortunately, today, as a result of government regulations and demands from superintendents, most turfgrass pesticides are far less toxic than they were 30 to 40 years ago.
To support that statement, I contacted three major pesticide manufacturers. All agreed that toxicity levels in turfgrass pesticides have decreased dramatically over the past 30 to 40 years, though none knew the exact numbers. The current breakdown of toxicity labels from the three manufacturers is: 61% Caution, 36% Warning and 3% Danger; 83% Caution, 6% Warning and 11% Danger; and finally, 95% Caution, 5% Warning and 0% Danger.
A direct result of decreased toxicity concentrations in agricultural pesticides includes a drop in the number of animals on the endangered species list, which first appeared in 1967. The American eagle, peregrine falcon and brown pelican are among the animals that have been removed from the endangered species list specifically because of decreases in pesticide toxicities. Other species taken off the list include the alligator, bears, wolves and Canada geese, but the population increases in those species are more closely connected to conservation efforts than to changes in pesticides.
When I returned to college in 1990, I learned Bt was only effective when applied during the early stages of the target's life. In reflection, I know the Bt application I made provided nothing more than spending money for the salesperson. I also know my nitrogen rates and potassium levels were too high for cool-season grasses, and I most likely overwatered daily — all of which can encourage pests.
Reduced pesticide toxicities are good for the applicator, sensitive individuals and the environment, but they also demand that current superintendents be far more educated than we were in my day. An understanding of a pest's life cycle is necessary to achieve maximum effectiveness with many of today's pesticides, and successful superintendents now use cultural practices to encourage turfgrass health. The pesticides I used were analogous to dropping a nuclear warhead on a house — effective, but overkill.
Since 1990, I have performed well over 1,000 research studies, reviewed many scientific papers and attended numerous conferences. Like all other turfgrass researchers, I have focused primarily on one discipline to become an expert. For me, that discipline has been cultural and mechanical practices. Given the facts, I am certain about one thing: I am no longer qualified nor capable of being a golf course superintendent, because I lack the diversified skill set required for the position. That's also true of my researcher peers and most consultants. So, when you're seeking their advice, know their area and level of expertise, which will help you know whether they're guessing.
Many of the big hammers I had in my pesticide arsenal are gone, while others are now formulated at active ingredient (ai) concentrations that decrease toxicity. That's why you can purchase the ai 2,4-D under a "Danger" or "Caution" signal. Today, superintendents have many options, and that's a very good thing. In any event, if anybody is looking for an employee to mow their rough when I retire, give me a call. I think I'll still be qualified.
Thomas A. Nikolai, Ph.D., the “Doctor of Green Speed,” is the turfgrass academic specialist at Michigan State University in East Lansing, Mich., and a frequent GCSAA educator.