COMMENTARY BY DR. DAVE SAMUEL
It started with a small three foot patch of brown in my lawn.
Two long years of aerating, seeding, watering and we finally had a respectable Greystone lawn.
That brown spot wasn’t a concern. I just thought that I’d mowed too low and with the hot temperatures, it browned the grass. Wrong.
Four days later, that brown area covered half the yard, but I still just felt that I needed to mow higher next time.
Then I went to the Greystone picnic and sat beside my friend, Billy Atkins.
As we chatted, Billy showed me pictures of his brown lawn and said he’d been invaded by army worms.
I got a sick feeling as I Googled army worms and realized they were killing my grass.
Within a few more days almost all of my yard was gone.
I posted pictures on Facebook and learned that many residents in our area were hit by army worms. And in driving around I’ve seen brown patches in yards where the owners don’t know they have worms, but they soon will.
Golf courses are susceptible and I know that the course near my home has been hit with army worms.
Why are we seeing army worms? The fall variety of army worms are not common in the North, because they are susceptible to cold weather. However, when you have very hot August temperatures with sporadic heavy rain, they can occur. A perfect storm for us.
You might see the adult moth of the worm flying around your yard. I know I did and didn’t give them much thought. The moths mate at night, and the female lays up to 1,000 eggs in masses on anything near your lawn.
If there are lights nearby, the moths are attracted and lay eggs on lamp posts, small trees, etc. Then they descend to your yard and go through several larvae stages.
The larvae stages eat your grass. Early stages eat little so they aren’t noticed, then the later larvae really do the damage in a few days.
They are most active feeding in early morning and late evening, and if you study brown areas, you can see them. Small, about the size of a tent caterpillar. From eggs to adult larvae takes 2-3 weeks and the adult worms emerge thereafter and the cycle starts over.
The worms do not eat grass roots, so if you get an insecticide on your lawn quickly, your lawn may recover over the winter.
Some grasses are less susceptible to damage. Healthy Bermuda grass recovers because it has strong root systems. Newly seeded ryegrass may be stunted or die. There are various sprays and granule insecticide applications that work.
From what I’ve learned, most any insecticide, whether a spray or in granule form, will work.
I used some granule Sevin and I think it may save a little of my yard. The good think about granule forms is that rain helps. Spraying before rains apparently isn’t helpful.
Whatever you use, the key is to get on them early.
Watering after, or fertilizing after, won’t help your yard repair itself. My lawn service couldn’t come and spray for a few days because of all the rain.
Frankly, by then it won’t matter. My hope is come October I can aerate and reseed once again and with luck I’ll have lawn next spring. I hope you luck is better than mine. I hate army worms.
