The one question to ask before spraying pesticides

The last couple of weeks, I have had the opportunity to teach plant diagnostics to a few garden clubs and Master Gardener volunteers. This is the best part of my job — teaching others about horticulture.

After going through the diagnostic process that begins with identifying the plant, the common problems for the plant, the pest in question and other steps, one of the final questions to ask is “so what?”

People look at me funny after we go through the process and figure out the problem, and I come back with, “so what?”

I follow up with the question, “what is the significance of the pest?” Is this something that if left unchecked or untreated will kill the plant?

The answer to this question depends on your perspective. For instance, turfgrass rust has been a problem recently throughout the state. This is a typical late summer and fall disease that develops easily when we have warm, humid, cloudy weather followed by hot sunny weather.

One of the steps to managing this disease is to apply good turfgrass cultural practices, including a good fertility program to promote healthy growth, avoiding moisture stress (but don’t water in the evening), raising the mower height and preventing compaction.

Another option is to overseed the lawn with newer cultivars of grass that are resistant to rust. Many home lawns are fairly old and the cultivars used in the past are susceptible to this disease.

Spraying a fungicide to control rust can be quite costly. In addition, rust seldom kills a lawn.

Knowing all of these factors, the “so what” answer for me is to not worry about it and work on the cultural practices. As soon as the weather changes, it will not be a problem.

However, the “so what” for golf course superintendents is much greater due to the fact that they can’t afford rust on the fairways and will focus more on the cultural and will possibly spray.

The main problem with this disease is that when you walk across a lawn that has rust, you will end up with orange tennis shoes. I just stay off the lawn with my white tennis shoes during this time.

On the other hand, a golf course superintendent can’t afford this type of situation so is more inclined to manage the disease.

My point is to take a closer look at the pest problems you are dealing with in your landscape and ask yourself “so what.” What is the significance?

If you need help, your local OSU Extension offices can also help to diagnose a pest problem and educate you on the so what.

Another hint: Water if you haven’t gotten sufficient rain for your plants in the last few days.

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