Monday, May 9, 2022

Still Dry - Chinch Bugs


Horticulture Hotline 05/09/22

By Bill Lamson-Scribner


The wind and the lack of rain has kept brown patch in check for the most part; however, powdery mildew, localized dry spots where irrigation is not reaching, and roaches that would normally be happy outside are coming inside for water as well as rats, are keeping us busy. When it is this dry for this long, insects that are usually happy in the woods begin to attack plants in people’s yards that are irrigating. Plants need water, so scout for insects. Snakes are out and about. With dry weather mole cricket damage is extra bad. Mole crickets separate the soil from the roots, drying out the grass plant. Wetting agents have been a big hit – a great product that saves you money. As predicted, chinch bugs are sucking the life out of certain grasses.


‘The Nasty Rascal, The Chinch Bug’ is about impossible to see (about the size of fine ground pepper), the damage can be confused between fungi, dry areas, and just dead areas, and although they are easy to kill once identified, the chinch bug keeps coming back. Chinch bugs preferred diet is St. Augustine grass (AKA Charleston Grass); however, it will attack zoysia, Bermuda, and centipede. As St. Augustine grass is getting replaced by zoysia, this switch in diet makes a lot of sense.


In the old days (Dursban, Diazinon), you could put out a product in May and pretty much control chinch bugs for the season. Now depending on the product, if you get two to three weeks control you are lucky. Most of the products work on the adults and do not affect the eggs that are waiting to hatch.


 There are a lot of cases of resistance to certain control products in Florida, so be sure to rotate chemical families of your products (not just product names). Since some of our sod comes up from Florida, we have also experienced these resistant chinch bugs as well.


‘The Nasty Rascal, The Chinch Bug’ got this designation from attacking family’s lawns during the summer while families were taking their summer vacation. The fact that this very small insect and a lot of its buddies can wipe out a beautiful yard in a very short period of time is ruthless. Hard to control weeds like bermudagrass and Virginia button weed always seem to move in on the weaken areas.


There is a fungus in the soil that controls chinch bugs. When the soil dries out the fungus in the soil that keeps chinch bugs in check dies. When the fungus dies, the chinch bugs go crazy. The reason you see chinch bugs along the road, driveway, sidewalks or in the sunniest part of the yard is because that is where the fungus dies out first. Chinch bugs rarely attack grass in the shade (notice attached pictures) because the fungus keeps them in check. With about 50 people moving to the Lowcountry a day, I wanted to make people aware of ‘The Nasty Rascal, The Chinch Bug’.


Since chinch bugs attack the grass along the road, driveway, and sidewalks, when people treat for them, they often throw product on hard impermeable surfaces (roads, driveways, and sidewalks). Always be sure to sweep or blow any particles back into the grass to avoid any unwanted runoff into storm water drains or marshes and waterways. This particular runoff situation would be another reason to refer to this pest as ‘The Nasty Rascal, The Chinch Bug’!


If you have active chinch bugs, be sure to use a product that ‘controls’ them not ’suppresses’ them. Sevin is a good choice with the resistance issues.


Always read, understand and follow product label. The product label is a Federal Law.