We don't need a bona fide drought to cause a serious insect infestation. But with so little rain for more than three months, chinch bugs are adding insult to injury. Drought conditions are desiccating lawns left and right, and putting out a huge invitation sign to these dreaded pests.
It's important to know the difference between drought damage and chinch bug damage. If left untreated, this bug will suck the life out of your St. Augustine lawn — it will literally kill it. Most chinch bug advice just focuses on killing the critters. Rarely is it emphasized that bug treatments aren't going to help the grass grow back. Dead grass has to be replaced.
A well-watered lawn is the best way to keep chinch bugs at bay.
So, how do you know if you have a chinch bug infestation? The first tell-tale sign is yellow spots. People often misdiagnose yellowing as an iron deficiency or fungal disease. So, they spray with a fungicide or apply iron — in some cases, even fertilizer. And if the problem is chinch bugs, all that fungicide and fertilizer is in vain. In fact, to make matters worse, applying too much nitrogen from a fertilizer on a drought-stressed yard is like pouring gasoline on a fire.
So, if you start seeing yellow, irregular patches in the lawn, first find out if the cause is chinch bugs. Get down on your hands and knees and do a little investigation. If you see tiny flea-sized bugs with white wing pods on their sides, you have chinch bugs. The "juvenile" chinch bug looks something like an insect version of a clown fish. They have a mostly orange body with a white band through the middle.
Another test I recommend involves shoving a coffee can an inch or two into the soil on the green-yellow edge of the patch. (For my Aggie brethren, remove the coffee first ... and open both ends of the can.) Fill the embedded can with water — if you have chinch bugs, they will float to the top.
Now, I have specific instructions for chinch bug control, and it always seems to differ from the advice of many garden centers and feed stores out there. DO NOT JUST USE A GRANULAR INSECTICIDE! For years, I've warned that you need to apply a liquid insecticide when treating for chinch bugs. Use a synthetic pyrethroid like bifenthrin, permethrin, cypermethrin or deltamethrin three times over a 21-day period ... or once every five to seven days ... up to four applications at most. You have to treat enough to break the egg cycle.
Sadly, many chinch bug victims use a granular insecticide, or they only make one application of liquid insecticide. Neither one of those methods will break the egg cycle.
So, can you use granular insecticides in any way for chinch bug control? Yes! While I normally don't recommend putting insecticides out for the sake of putting insecticides out, granular ones can be used as a preventive, especially when it's this hot and dry. But, again, it's not the answer to a full-blown infestation.
So, to bring things full circle for listeners who may have been on vacation for the past two weeks and have come home to a full-blown chinch bug infestation ... that grass that's all brown? It's dead. And no amount of liquid fertilizer will bring it back to life. Treat the yellowing edges and beyond into the green grass.
The key to success in chinch bug control, aside from using liquid insecticide, is to catch it early.
And what if you can detect no bugs? Well, it could be drought-related, could be a nutrient problem, could be a fungal disease. Or it could be an infestation by a completely different critter. Yikes!
Images: Turfmasters, Oklahoma State University, Florida Landscaping Today
Randy Lemmon's GardenLine is heard 6-10 a.m. Saturdays and Sundays,
exclusively on NewsRadio 740 KTRH.
Visit the GardenLine Home Page: http://ktrh.com/pages/gardenline2.html
Visit the GardenLine Facebook Page: http://www.facebook.com/home.php?#/pages/GardenLine-with-Randy-Lemmon/115129939929?ref=ts