Just when the latest round of Armyworms has finished devouring lawns, I get calls about chinch bugs.
You will typically see injury as yellow or dead drought-stressed or heat-stressed spots in the yard, most commonly in late summer. Infestations are usually initially localized because chinch bugs feed in aggregates. Injured plants occur in spots or patches that enlarge as the population increases and spreads. When infested lawns, high numbers of chinch bugs migrate by walking to neighboring lawns or other turf areas.
You’ve probably heard that you can find them by “floating them up” with a coffee can where the bottom is cut out. That’s true but I have better luck by simply parting the grass and quickly looking for the bugs darting around and looking for cover. Another method is to sprinkle an area with a dilute liquid dishwashing soap solution (1 oz. soap per gallon of water to 2 square feet of grass). This is irritating to chinch bugs and other insects and they should come to the surface where you can more easily see them.
Our beloved St. Augustine grass is the favorite host of the southern chinch bug. Other grasses they will attack include Bermudagrass, Bahiagrass, Centipedegrass and Zoysiagrass.
Adult chinch bugs are almost 3/16-inch long, have black bodies and fully developed wings that look white. Adults appear as either long-winged or short-winged forms.
Newly hatched nymphs appear orange red with a pale whitish band across their abdomens. As they molt through five growth stages (instars), nymphs gradually change color from red to orange to black and develop wing pads as they develop.
Nymphs and adults use their sucking mouthparts to remove sap from the base (crown) and stolons of plants and inject a toxic substance that prevents the plant from transporting water.
Adults overwinter in protected places like weeds and grasses, becoming active in the spring. During mild winters and probably in southern Texas, all developmental stages may survive. Mated females lay eggs singly behind leaf sheaths or in the soil around host plants. Wingless nymphs hatch from eggs in about two weeks and develop through five stages for about 30 days before becoming adults. The entire life cycle can occur in about 6 weeks or longer, depending on temperature.
There are many active ingredients that control chinch bugs effectively, but formulations, sites for use, and applicator requirements, vary widely. Always consult the product label for specific instructions on application rates, methods, and timing.
Many products that are labeled for chinch bugs recommend watering the product into the turfgrass canopy. This watering maximizes control by placing the active ingredients into direct contact with the chinch bugs.
Be sure to scout and positively identify their presence before applying any control product. Failing to properly identify the targeted bug and improperly applying some a measure of control will waste time, money and set up for more problems later.
