Insects, diseases and weeds, oh my! Keeping these pests at bay on a golf course is a constant challenge, but good results are increasingly achievable with the help of modern pesticides. Still, sometimes pesticides do not deliver the results one might expect. Perhaps the treatment timing was off, or the rate applied was too low? Maybe the product selected is not an effective control option, or a large percentage of the pest population has developed resistance? These issues are often the first things that come to mind when a product comes up short. What is often overlooked, however, is the role that water quality plays.

It should come as no surprise that water quality plays a key role in the effectiveness of an application. After all, the vast majority of a given spray mixture is comprised of water – often more than 95 percent. Despite being such a huge percentage of what is applied to the turf, the water itself often receives little thought when planning an application. Measuring a specific volume during the mixing process to achieve a desired dilution is typically the only attention water gets.    

Superintendents could learn a thing or two from farmers, who routinely adjust the water carrier before adding a pesticide to the tank. This is a simple, low-cost step that can increase the effectiveness of certain pesticides. So, what water issues are farmers trying to overcome and how do they make their water better?

The two main attributes to consider when evaluating water quality that can negatively affect pesticide performance are pH and hardness.