Treating Insect Pests in Turf

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I never really thought of lawns as a place to protect pollinators, but I was reading an article a week or so ago that talked about protecting the pollinators in the lawn. The idea behind the article was that many of us have weeds in our lawns that produce flowers that are visited by pollinators. August is a time of the year when insects that cause damage to turf are often peaking in numbers, making it the ideal time to treat for insect pests in turf. However, many of the insecticides that are used may also kill pollinators if they come in contact with the insecticide. The article suggested mowing the lawn to remove any flowers prior to making the application of insecticide. Fewer flowers would logically translate into fewer pollinators.

Before making an insecticide treatment, there are a couple of other insects to consider as well. Beneficial insects including Scoliid wasps and Cicada killer wasps can often be found flying around turf during the month of August. Scoliid wasps are the more common of the two. They are about the size of a paper wasp with two yellow dots on the top of the abdomen about half way down its length. These wasps fly low over the turf area listening for the movement of grubs in the soil. When they find one, they tunnel down and lay an egg on the grub. The egg hatches in a couple of days and feeds on the grub until the grub is completely consumed. Scoliid wasps are not aggressive unless they are being handled.

Cicada killer wasps are one of the biggest wasps we have in our area reaching about two inches in length with black and yellow stripes. The males will dive bomb people or animals that get close to the nest, but having no stinger, they won’t sting. The females are so busy digging and provisioning the nest that unless you grab them or step barefoot on the tunnel opening they rarely will sting either. If you do encounter a nest, keep in mind there is only one female per tunnel. If you let them do their thing, they won’t bother you either.