Damaging lawn insects are one of the most fun issues a technician can deal with, right? Wrong. Nobody likes to show up at one of their clients’ homes only to see that chinch bugs, army worms, grubs, or some other infestation has turned the property into an all-you-can-eat-buffet. Insects can easily spread from lawn to lawn and generally have a particular diet of grasses they are after. For instance, in Texas and Florida where the southern chinch bug is active, the main diet is St. Augustine Grasses. These bugs will eat around or at least wait until the St. Augustine is nearly gone before attacking Bermuda or Zoysia.

In the Midwest, chinch bugs were quite happy and healthy and in no way an over populated species, before farming took over the plains. They had figured out what to eat and not to eat for eons before man came and planted wheat and corn. Suddenly, the chinch had something new to eat, something sweet and full of proteins that were part of the grass family. The infestation and destruction to the crops were devastating. Then someone had an idea, the bugs only like grasses, so lets all plant soy beans. It worked. The bugs were all but annihilated, that is, until they found turf grass.

After World War II, game-changing advancements were made in the areas of fertilizer and pest control. DDT was hailed as the biggest advancement in insect control in the history of mankind. The inventor received a Nobel Prize. Trucks, planes and even helicopters applied DDT all over the world. In 1962 Rachel Carson wrote the book “Silent Spring.” Her studies on the food chain detriments of applying DDT led to a nationwide ban. Too much of a good thing.

Bugs tend to start their life cycles early in the year as a general rule. However, they become the most active when soils begin to heat up. For Chinch, the target temp is 85 degrees. Consider what it takes to get soil to 85 degrees. Drought or under-watering, areas next to stone or cement, areas where grass is thin due to heat reflection from windows. Watering and proper fertility should (in theory) prevent and nearly eliminate the need for any extra controls. This is very important because any insecticide applied will have a magnification effect on others in the food web. As stated before, do not take something out without adding something back in. Our job is to make our clients properties healthy, which requires that pesticides be applied when needed. The ripple effect is what needs to be addressed for the post application spray.

There is a very important message in all of this: take a look at what grasses chinch are attracted to and why. Historically, chinch bugs have gone after wide bladed grasses with a thicker cell wall. When a lawn is fertilized with heavy doses of Nitrogen, the grass has to metabolize quickly and enters a “grow or die” stage that forces the plant to stretch. When the blades stretch, the cell walls thin and become susceptible to insects. On the flipside, the nitrogen that is being used is converted to protein, which gives the plant a more nutritional aspect for bugs. So the message being sent to invasive bugs is, “I am weak… but I am delicious.”

Dr. Michael Kolomiets at Texas A&M University has discovered something even more fantastic about the way grass communicates with its environment. He studied the biological aspect of “fresh cut grass” smell. What he discovered was that the odor being put off by the plant was actually a signal to beneficial bugs that the lawn was distressed and it needed help to fend off invasions.

Now put it all together and think about the program you are currently using for fertility. Lawns fed with high nitrogen doses (university recommendations) are more likely to become stressed out than lawns on a controlled, lower input diet. Lawns on the high nitrogen program will need to be cut more often and therefore will be sending distress calls more often. So the next time you get a call about an infestation, remember: the lawn had been calling out for help long before the homeowner knew there was a problem.

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