Grubs Worms in NW Indiana – Myths And Facts

By now, you guys know I am a lawn nut. Don’t tell anyone, but I pet my lawn and speak to it softly!   On a serious note, however, grub worms are a real threat here in NW Indiana and in this article, I plan to tell you EVERYTHING you need to know about them! Just follow along and if I miss anything, feel free to hit me up in the comment section below.

What Are Grub Worms?

Grub worms are the larval (baby!) stage of several types of May-June Beetles also know as Japanese beetles or Chafers. Not to be confused with the recent infestation of Emerald Ash Beetles in Indiana, most of you have seen brown bodied and green headed bugs buzzing around your porch lights and have called them “June Bugs.” These adult beetles emerge from beneath the soil in May and June, mate and then lay eggs in well irrigated lawns during later June, July and August. The resulting small, white worms (they look like little shrimp) feed on grass roots during August, September and October. Once it gets cold, then burrown deep to overwinter until the next Spring when they emerge as adults and the entire grubby process begins again!

Japanese beetles I pulled off my river birch last year

How Can We Stop/Prevent/Kill Grub Worms?

In case you aren’t aware, the best way to save your lawn from damage by grub worms is to prevent the problem in the first place. But before you go slathering a bunch of chems all over your turf, is it really needed? Pretty much EVERY lawn will get some grub worm activity within it. It is only when the population exceed about 4 pests per square foot that we will have a noticeable issue.

You see, if you are fertilizing your lawn properly, keeping it mowed tall and irrigated — and it is already THICK and healthy, then you really have very little to be concerned with. For me and my lawn, I only treat for grubs if I notice a problem in the early fall, and at that time I use chems in small doses only in effected areas.

BUT WAIT– I take time and monitor my lawn. If you don’t, then you should definitely treat your lawn for grubs and avoid the possibility of trouble!

grub damage is identified by sections of lawn that peel up like carpet

When, What and How To Treat For Grubs

The best time to apply your grub prevention is June or July. Anything earlier and your application will not subsist long enough in the soil to fully protect the entire season. On the flip side, apply too late and your application won’t be effective because the larvae will be too large and less effected by the insecticide. Grub worms in the early Spring (March, April, May are NOT a concern, see below for details on Spring Grubs).

Most of the effective grub controls on the market come in granular form and should be applied with a broadcast spreader. I am not a big fan of grub controls that are also mixed with fertilizers because of the high nitrogen content, but if that is all you can find, then so be it.

What Is Grub Insecticide Made Of?

The best grub controls on the market today are neonicotinoides. Without boring you too much here, neonicotinoides act on the central nervous system of insects in the very same way “nicotine” acts on the central nervous system of humans.

Think about this: people who quit smoking eat a lot right? Yeah, because nicotine is an appetite suppressant! So when you place a nicotine type product systemically inside of a plant (like grass plants) when the insect (in this case grub worms) takes a bite or two, it ‘feels’ full and stops eating! And this is how most of the grub controls on the market work today. This is good because they have little-to-no negative impact on mammals. (though, there is some research suggesting neonicotinoides may effect honey bee populations negatively)

On the market these days, brand names are what you will need to look for, and ‘Merit’ is by far the most effective form of neonicotin available. The key after application is that you water it in immediately so it dissolves into the soil where grass roots can begin uptake immediately. A couple popular grub controls that contain Merit are listed below.

Now it is also important that you read the next section about moles and grub worms…

my lawn is so thick, I am not concerned with grubs; but you should be!

Grub Worms And Moles/Voles

Over the years I have heard people say, “If I treat my lawn for grub worms, then I won’t have anymore mole problems.”

Folks, that is a myth and here is why:

First off, as I said above, the grub worm prevention products on the market today do not directly kill the grubs, they only curb their feeding activity. The grubs are still there in the lawn, albeit they are under-nourished! A mole tunneling in your lawn doesn’t care that the grubs are skinny.

Next, moles aren’t that smart and will still be tunneling in your lawn looking for grubs no matter if they are there or not. If you have mole issues in your lawn, it is because you live near woods or some other natural area that is a normal habitat for moles anyway.

Finally, moles eat earthworms and other ground dwelling insects other than just grubs. So long story short, controlling grubs is NOT an effective form of mole control.

Spring Grub Worms A Problem?

Another myth associated with grubs is the idea of treating for them in the Spring (March, April and early May). I can tell you that if you dig around in your lawn in the spring and find them, they are NOTHING TO WORRY ABOUT! Those grubs are last year’s and they are about to emerge as adults. Now, they do feed a little in the spring before jumping into beetle land, but your grass grows profusely in the spring… so fast that it out-grows the minimal damage caused by spring grubs… so don’t waste your money by treating for grubs in the spring! Wait until June and July and treat then… don’t jump the gun, it’s not needed.

Can Beer Stop Grub Worms

Oh man, this one is my favorite grub worm myth! I really don’t know who started the rumor that you can kill grubs with beer, but I intend to clear it up here for ya.

YES, you can kill grubs with beer… in fact, enough beer will kill ANYTHING. But beer is not an effective grub worm control for lawns and here is why:

First, what kind of beer you gonna use? Something strong in alcohol and very bitter and hoppy like Crown Brewing’s American Pale Ale? Or are you gonna use something lighter like Miller Genuine Draft? How much will it take, and how do you calibrate the sprayer? You see how foolish this is? Not all beer is created equally now is it?

Wacko summer Lager $8 for a 6-pack. You'd have to be a 'wacko' to waste this on your lawn!

Second, have you ever smelled beer that has been spilled in grass and then rotted in the sun? Just go to any outdoor concert featuring Ozzie Osbourne and hang around the next day and tell me if you want that smell at your crib?!?!

Finally, and most importantly is the cost! If beer really did work as a grub worm preventative, how much would it cost you to spread it all over your lawn? Maybe 4 kegs of Amstel Light eh? What would that cost, $400 – $600 for a small lawn in-town Crown Point? What a waste of good beer eh?

The guy who came up with the beer and grub worm myth was obviously not a beer lover like me!!!! I’d say he needs help for his alcohol abuse!

Grub Worm Conclusion

Ok, so if you are skimming this article, this is the end and here is my advice: Get your grub worm preventer now (July) and put it down this weekend and water it into the soil and be done. Easy!

Side Note: Our editor and publisher, Allyn is a lawn care professional based in NW Indiana. He hates being called that, but it’s true. (and yes, he does pet his lawn and speak softly to it)  He holds pesticide applicators licensing in Indiana and Illinois and has been kicking grass since he was 14 years old. In addition, he likes to drink beer while blogging and that is why he so often shows pictures in unrelated stories of the most excellent craft beers he is drinking at the present time.

1. 

   Joe Porter says:

   July 13, 2010 at 9:39 pm

   Actually Miller Genuine Draft or anything like it will kill anything in sight. Dont Drink it!! its bad for you.

   reply
   • 

     Allyn says:

     July 14, 2010 at 12:37 am

     exactly, if you are gonna use cheap beer for lawn care, give it to the grubs where it belongs, lol

     reply