Controlling Chinch Bugs in Your St. Augustine Turf



Adult (with wings) and Pre-adult (without wings)  Chinch Bugs

Many times a homeowner may treat his lawn for chinch bugs or have his yard professionally sprayed and assume the chinch bugs will be controlled. However, for various reasons such as resistance or poor application technique, damaging numbers are left behind. This leads many to the assumption that the problem is a fungus. To be sure the problem is chinch bugs, homeowners need to learn how to recognize these pests. There are many pictures of chinch bugs on my web site. You can use the soap flush method to find them. Make a soapy solution (1.5 ounces of dish soap per two gallons of water) and pour on a 2x2 foot suspicious spot. The soapy water will bring the chinch bugs to the surface in about five minutes or less.

 

Early Instar Nymphs Which are Pink With aWhite Strip

However, I think the best method to find chinch bugs is to get down on hands and knees in a suspicious spot, pull the stolons apart all the way down to the soil, and look for these little bugs. They are fast and small. Look in areas which are affected (not all green, not dead) and look in many locations. The adults are about 1/8 inch long, black with white wings lying flat on their back. The pre-adults are entirely back with no wings. Early instar instar nymphs are red with a white stripe across their back. If you belong to a homeowner’s association, perhaps two or three members could become the chinch bug experts. I am happy to help train these volunteers.        

Chinch bugs are becoming more difficult to control as resistance has been reported to the widely used class of insecticides called synthetic pyrethroid products like bifenthrin (Talstar), permethrin, cypermethrin, deltamethrin, etc. I have heard frequent media advertisements lately for the product called Triazicide (gamma cyhalothrin)  which is just another synthetic pyrethroid. When insect resistance develops to one product in a class of insecticides like the pyrethroids, then the resistance spills over to all products in the same class. A common homeowner product with bifenthrin is called OrthoMax Bug-Be-Gone and is commercially called (Talstar).

Chinch Bug Damage in Heavy Fertilized St, Augustinegrass
 (right side of plot) versus normal fertilization (left
side of plot).

If you, as a homeowner, are buying your own product and applying it yourself and have had problems controlling chinch bugs for several years, then I suggest you buy a product with clothianidin (Arena). I would treat the whole section of the lawn which has had or currently has a chinch bug infestation. This product is available at some of the box stores as Green Light Arena and at John Deere Landscape Supply as just Arena. However, John Deere only has Arena in 40 pound bags – Green Light Arena at retail stores is in 12 pound bags and covers 4,000 square feet.

Be forewarned that over nitrogen fertilization will make your St. Augustinegrass much more attractive to chinch bug infestations.  The above photo displays chinch bug damage on the right side of the plot which has been over fertilized with nitrogen. While the left side of the photo displays chinch bug damage to St. Augustine turf which has received recommended nitrogen rates. The chinch bugs obviously prefer heavy fertilized lush turfgrass. Not to say that they will not eventually move to the left side of the plot for greener pastures.