Grubs In The Lawn - Questions and Answers

Being as we are almost to May, it’s also time to think about grubs in the lawn.

I am mainly talking to you folks with cool-season turf as your grass types are most susceptible to grub damage, but even you all with Zoysia, Bermuda, St Aug, and Centipede can see some damage from them if populations get too high.

I am predicting that this will be a pretty bad year for grubs since we had a very mild winter across much of the country.

One thing that a harsh, deeply frozen winter will do is kill off some of the population - but this year, we did not get that and in fact, just the opposite: a fairly mild winter.

Here is a graphic I drew for you that shows you the life cycle of grubs to better provide you with understanding on what I am talking about here:

As you can see, you will find grubs in your lawn here in the spring time, but those are last year’s crop, ready to emerge in June (June Bugs) to start a new life cycle.

It’s these summer hatches that feed on grass roots all fall time and cause the most visible damage to lawns.

Here is a complete video taking you through the different products to use:

I’m going to answer some questions about that video below, but I also wanted to provide you written instructions on all of this, including going into the detail of how to apply these products.

I show you step-by-step in this FREE guide and have a video to support it.

If you are new, and have never applied anything to your lawn before, learning with a grub control application is a good way to start.

You can have zero fear of burning anything - (you shouldn’t fear this anyway) - and you can learn pretty quick.

Pick up the FREE guide to stopping grubs here.


Questions On Grub Control

Does Grub Control Stop Moles or Racoons or Skunks?

By far this question came in the most asking if getting rid of grubs will take care or, or reduce a mole problem. The short answer is, “yes it reduces one of their food sources, but it’s not a way to get rid of them.”

Moles do like grubs, but they also like earthworms, beetles, and other bugs that live in our lawns.

A grub treatment will ding your earthworm population too but that is just not a good thing to think about is it?

It certainly doesn’t seem right to me.

Truth be told, if you have problems with moles, it’s because of where you live, not what’s in your lawn. I have a mole that gets in my lawn too, I just deal with it.

Moles are a scourge to be sure - even most pest control companies won’t try to eradicate them, instead, they just tell you to live with them too.

Other varmints will feed on grubs too - those being skunks, raccoons and even wild pigs here in Florida. The thing about these jerks is they know the signs.

They know that dead patches in a green lawn often mean there is a meal underneath.

And once they enjoy eating out in your backyard kitchen once, they tend to come back night after night - and they are LOUSY tippers too!

So keeping grub damage out of your lawn by treating for them can and will reduce damage from animals in the lawn. But it’s not a guarantee.

My parents had a lab named Sunny who used to dig up and kill moles all the time. She also got sprayed by a few skunks chasing them out of the lawn. So that is always an option too.

Either way, the decision to treat is up to you, but don’t treat for grubs solely based on a mole or skunk problem.

How About Environmentally Friendly Alternatives?

This one gets asked often too and sometimes it comes across as the screenshot above asking about milky spore, other times it's beneficial nematodes, but in summary, people want an alternative to the “chemical” controls.

I have had experience with milky spore for grubs. When I say that, I’ve known people who have used this strategy with success that is debatable.

Milky spore is a bacteria that you apply to your soil - it’s a biological control.

Milky spore takes a while to build up in the soil - populations must increase.

They can increase from you continually adding them year after year, and can also increase as grubs inhabit the lawn for them to infect, kill, and increase that way.

If you plan on this strategy to control grub populations you need to plan on starting now and following the labeled directions for a few years.

Because milky spore is a biological control (living things) it is susceptible to die back just like anything else living in your soil.

A very dry summer or super cold winter can knock back all of your progress - making this strategy one that requires diligence and continual additions.

The way it works is the bacteria get into the grub via the mouth and kill it from the inside out, and when it dies, more bacteria are released - just like the alien movie!

Back to friends I’ve had who used it with success: the thing about it is their lawns were super thick and healthy anyway.

Sure, they had years with no damage from grubs when others around them did, but was that because their lawns just “grew through” any damage or was it from the milky spore? I don’t know.

My lawn in NW Indiana never had a grub treatment in the 10 years I lived there and I never got grub damage either, while others around me did.

So the evidence for milky spore is anecdotal at best, and expensive.

It’s around $50 for 7,000 sq feet but you need to apply it every year for several years to get enough build-up to know you are good.

Just seems expensive for anecdotal control. This is why I recommend “Integrated Pest Management” that I talk about below.

As far as the beneficial nematodes, I have not had direct experience with them, however, based on my reading and research, here are my thoughts.

For sure they work against grubs if you are diligent. This article from a trusted source, University of California gives you some good info.

  1. You must apply when grubs are alive and active in the lawn so you’ll need to know where they are so you can target them directly. This makes the nematode strategy a “curative” strategy, NOT a preventative one.
  2. You have to get the right species of nematode for grubs and that is Heterorhabditis bacteriophora (Hb) which will get insects below the soil surface.
  3. You should apply at night as sunlight will kill your nematodes and you need to water them in.
  4. Soil must be moist before and during application and kept moist for at least 10 days after the application. Soil that dries out too fast can kill the nematodes.
  5. Cost seems super high! I find conflicting info on this and I don’t want to link you to products that I have not personally tested, but general consensus seems to be that about 5 million of these buggers are needed to treat 200 sq ft. Pricing is about $30 for this. With the “chemical” stuff I can prevent grubs in a 5,000 sq ft lawn for $30. This is a curative strategy and costs $30 for 200 sq ft. So cost wise, this is MUCH more expensive.

But… here’s the thing that concerns me about any kind of “bugs in a jug” application, nematodes, milky spore, anything like that.

If you are introducing high populations of an organism into your lawn, oftentimes the naturally existing organisms in your soil can suffer.

There is a certain balance in soil and while we don’t want to upset that balance with too much chemical application, we also don’t want to upset it with an over-abundance of biologic applications either.

I’ve watched too many zombie movies probably, but it stands to reason that something “unnatural” being introduced, even if it is a biological control mechanism, could be a problem.

Did you know that milky spore is actually classified as a disease? Sounds pretty scary to me, even more scary than a “chemical!”

Integrated Pest Management

This is why I recommend you follow the practice of Integrated Pest Management. I talked about it right here in the video.

This strategy says to only use a “chemical” control when you notice that populations of pests will have a negative impact on your primary crop.

In our case, the primary crop is turfgrass and if insect populations get to a point whereas to start causing visual damage to said, crop, then we treat.

Putting It All Together

So here is the strategy I have always employed when it comes to grubs: keep your lawn super thick, vigorous and growing, this includes keeping it well irrigated in summer.

At the first sign of any brown spot/patch in the lawn from July-October, the first thing you do is dig.

See what is under that brown spot and if you find grubs, spot treat only that area and the surrounding 2-3 feet with a curative grub application using an active ingredient such as Dylox or even Bifenthrin can work. Continue to monitor and spot treat as needed.

Alternative: if you have had grub problems in the past 2 years where visible and major damage has occured, or your neighbors have, then you should apply a preventative treatment to your lawn right now sometime in May.

Use Scotts GrubEx since it works well and is easy to find at any HD, Lowes, or Ace and is fairly cheap. (no, they are not a sponsor).

Like I mentioned, I do predict this to be a pretty bad year for grubs so if you have seen issues in your neighborhood, or better yet, your local county extension is writing articles talking about a looming threat, you should also go ahead and treat with a preventative now.

I hope this has been helpful to you!
I’ll see you in the lawn!