Grub Damage in the Minneapolis Area

So you’ve been doing everything right for your lawn, mowing tall, fertilizing at the right times, and watering when mother nature isn’t cooperating. It looks real nice. Like, REAL nice. The PGA tour is calling looking for your secret sauce kinda nice. It starts getting some brown spots. No problem you think to yourself as your watering, thinking its dry. The next thing you know their bigger. “Maybe it needs a little fertilizer.” You think to yourself as you pour the perfect amount of fertilizer into your spreader. Sidenote- how good of a feeling is that?

Bigger, bigger, bigger that spot gets and now you start to notice a couple more nearby. Then BAM. Your lawn looks like my dogs, ughhhhh, “special presents”.

You should see the spring time cleanup, absolutely ridiculous

What. Has. Happened.

Just yesterday you could have sworn everything looked great and now this?

If you’re in the Minneapolis/Richfield area there’s a good chance you got hit by Grubs. Over the last few years, these little suckers have been taking lawns out of commission.


What are grubs?

White grubs are the larval stage of  many different beetles Japanese Beetles and June bugs are typically the end results from these grubs, especially in MN. This larval stage is when the do the damage to your turf.

Their life cycle

The grub life cycle can be a little different for each type of beetle but overall they are similar. Hatch. Eat. Overwinter. Eat. Transform.

First, a grub will hatch from their egg during mid summer. They’ll immediately start chewing on the root system of lawn and that’s when you might notice some small brown spots forming. They’ll continue to feast on your turf roots throughout the fall and that’s typically when most homeowners see the damage and start worrying. At this point, the grubs are big, and their appetite only grows as they continue to munch away until old man winter decides to awaken.

Once it starts getting cold, the grubs will begin to burrow deep into the soil to over winter. Lucky for your, they finally have stopped causing damage. Until spring at least.

It’s getting warm. The sun is finally doing its job. And your get to see your beautiful, green, AWEFUL, DEAD, DIRT SPOT RIDDEN LAWN.

AHHHH WHAT HAPPENED?

Grubs my friend. Grubs.


**Attention

If your a Fertilawn customer, PLEASE CHECK YOUR AFTER SERVICE EMAILS. Our Lawn Techs have been trained to check for grubs if they spot damage. If they find any, they will let you know! It’s very important to treat these as soon as you see damage**


Spring is usually the worst time of the year for damage as the rest of your lawn is greening up nicely, but the areas that you saw browning out last year are basically dirt pits. They’re not done though. As it gets warmer, they start to get closer to the surface and continue their feeding frenzy, getting monsterly big, until early/mid summer.

At this point, they finally start their next life cycle, turning into the beloved Japanese Beetle.

Beloved, amirite?

If that white grub was in fact a Japanese Beetle, they will emerge from the soil and continue their all-you-can-eat buffet on your surrounding shrubs and trees. After which, they’ll mate, lay their eggs in the soil, and the cycle starts all over again.

One thing I absolutely should note before I go on. Having Japanese Beetles does NOT mean you will have grub issues. The same thing goes for applying anything to take care of the grubs. If you hit the grubs with an insecticide, it doesn’t mean you will also get rid of the Japanese Beetles, as they will fly in from all over the area to feast. From what I can tell, there is no reason why a beetle will choose your lawn over your neighbors to lay their eggs.


What can you do about grub?

The MOST effective way to treat grubs is to apply an insecticide before they have a chance to start feeding. This means early summer so that when those new ones hatch, they are easily controlled by that insecticide. The bigger they are, the harder they are to control AND the more product you need to use to get and decent results.

Suprisingly, we did not get 1 call about grub damage from any of our customers that had this spring treatment done. I honestly would have thought there would be some break through, but notta.

Applying grub control treatments in the fall (when most people notice the issue) requires WAY more material, and typically gets much, much worse results in terms of control. I can almost GUARANTEE you will not control that nasty grub population if you apply an insecticide later in the fall. I know it’s not what you wanted to hear. Sorry.

We try our best to inform our customers when we find grubs, but we always get some calls come fall about grub damage. What we tell people is that, if it’s bad enough, the lawn won’t fix itself and some type of seeding will need to be done.

In terms of controlling the grubs, we give them our spiel on their life cycle, and how the best time to control them is actually next spring, by controlling the following generation. We do, however, let them know we can apply something now and get some results. Albeit, not the best, but some results nonetheless. We really try to reiterate that the later it gets, the worse the damage gets, and the less products will work.

Most customers end up having us do an insecticide treatment ASAP and again in the spring, which is what I would recommend depending on how late in the year it is. (If the leaves have already started falling, I’ll typically reallllly try to reiterate that they should save their money this year and make sure they get the spring grub application, maybe spend that saved money on an aeration/overseeding instead.)

Lastly, we get calls ALL the time asking if they should get a grub treatment because they had Japanese Beetles or worse, they saw on the news how bad grubs are. Not EVERYONE needs this treatment. In my opinion, it’s irresponsible for ANY Lawn Company to recommend that everyone gets a grub application in our climate. If you have had damage in the past, or very bad damage last season, it typically is a good idea however.

The nice thing is most lawns can support a healthy grub population without seeing a lot of damage. This is exactly why, in my opinion, not everyone needs it done.


Why are they so bad now?

What does the damage look like?

How to diagnose them?

To keep this from becoming a novel, I’ll get to that next time.