Answer: Chinch bugs are a common lawn pest that can damage turf when it sucks sap from grass with its piercing mouthpiece. Chinch bug damage gives the appearance of small round dead patches (brownish-yellow grass) and opens up areas for weeds to become established. When not controlled, large sections of lawn may die. This is particularly true of sunny, dry areas near slopes and the edges of lawns. Chinch bugs also cause damage when they feed and inject a toxic saliva into the grass causing it to wilt and die. Population size depends on the weather, with only small populations being produced under wet conditions. However, if the weather is hot and dry early in the season with minimal amounts of rainfall, a large population may occur. The chinch bug life cycle consists of egg, nymph and adult. The adult overwinters in a sheltered location such as hedges, leaves or dry grass. When warmer temperatures occur, the female chinch bug leaves the sheltered area and lays approximately 200 eggs on grass and soil in a dry hot area. The eggs hatch within three weeks producing young nymphs. The nymphs are smaller than the adults, approximately 1/20 of an inch, and are red with a white band across the back. The nymphs pass through five growth stages before becoming adults. Two generations of chinch bugs are usually produced each year.
You can scout your turf for cinch bugs slowly sliding your foot through the sod and watching for the bugs to crawl across your shoe. You can also determine infestations by using a large coffee can or gallon can with both ends removed. Press one end of the can about 2 or 3 inches into the soil, fill with soapy water, and watch for about 5 minutes. If chinch bugs are present, they will float to the surface. It is very important to check areas where the yellowish spots and the green grass meet in several different locations.
A well fertilized and nutrient-rich area can withstand a chinch bug attack. Thus, good lawn care is the best prevention against chinch bug damage. Understanding chinch bugs, the conditions they favour and their life cycle is very helpful in control. Keep the lawn well fertilized and take caution not to add too much or too little nitrogen. Use proper mowing techniques which include cutting grass two to four inches high, removing thatch, maintaining proper moisture levels, avoiding water buildup, aerating the lawn if it is compacted and using a resistant variety of grass. If physical methods are not effective, use a pesticide which will have a minimal impact on both you and the environment. Use an insecticidal soap spray on areas where damage has occurred. Diatomaceous earth can also be used to control chinch bugs. Diatomaceous earth is an insecticidal dust which acts as an abrasive. It cuts the outer layer of the chinch bug's body causing it to dehydrate and then die. Products containing pyrethrin can also be used.
Best wishes with your turfgrass.
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