Signs of grubs in lawn include very clear ones like thinning grass or discolored patches. Some signs could be more obvious, like the sudden interest in burrowing animals in your lawn at night.

Detection and Management of Grubs in Lawns

Knowing these signs to take timely action and carry out effective grub control to save your lawn.

Trust us, this is not a problem that you want to defer for later, or you risk the destruction of your lovely lawn and grass. 

List of Signs of Grubs In Lawn 

1. The Grass Seems To Be Thinning

A Possible Sign of Grubs Grass

  • Grubs eat roots
  • Grubs take away nutrients from the soil
  • Appearance of bald patches
  • Dry and wispy grass blades
Severity of Problem
  • Pretty severe 
  • Effective grub control
  • Over seeding the grass

The grass will suffer the most when you develop a lawn grub problem. If the grass is becoming thinner out at an alarming pace despite your best lawn care habits, there might be a grub problem, because they are the ones that tend to do this. You will only be able to regain lush and dense grass if grubs are properly dealt with.

Why do grubs aim to thin the grass? This is because they make a home in the soil near the grassroots and then begin to feed off them. Grubs take all the water and food from the roots and produce starvation in the grass.

They also damage roots directly, and you will notice how easy it becomes to uproot tufts of grass from the soil. The damaged roots provide no resistance to keep the grass anchored to the soil.

2. Unusual Amount of Beetles And Moths Around Grass

Beetle and Moth Populations in Lawn

  • Beetles and moss like to lay eggs on the grass
  • Grubs are larvae of beetles
  • White colored beetles flying low
  • Beetle droppings
Severity of Problem
  • Shows that an infestation is underway
  • Carry out beetle control
  • Call in professional help

White grubs that infest soil are larvae of beetles, and they stay there until they mature into full adults. These beetles are called the ‘water beetles’ and are small in size with brown-colored shells. If they have been laying eggs in the soil and maturing from the grubs’ stage within the same soil, you will eventually notice them in the lawn.

In this case, slowly but surely you will start seeing a couple of beetles in the lawn occasionally does not guarantee that you have a grubs’ problem at hand, and it would be clear to you. However, when they appear regularly in large numbers, it is prudent to check for grubs, especially if other signs of a grubs attack are also evident. 

Adult beetles like to fly low over the grass in search of spots to lay their eggs in. Unfortunately for you, they tend to look for the healthiest spots in the lawn for laying eggs and then proceed to destroy it. 

Never take the sudden emergence of water beetles lightly, and take immediate action. If you don’t know how to get rid of beetles and grubs yourself, then calling in professional help is always an option. 

3. Brown Circular Patches On Grass

A Common Indicator of Grubs

  • Weak grass 
  • Grubs feed on grass roots
  • Random appearance of patches
  • Brown-colored patches
Severity of Problem
  • A sign that emerges at the start of the grubs attack
  • Effective lawn care
  • Get rid of grubs from those areas

Along with thinning grass, grub infestations manifest as brown patches of dead grass spread randomly across the lawn. These patches are usually circular or irregular in shape and of various sizes depending on the severity of the infestation, and it would differ from one case to the other. This is a rather hard-to-miss sign because the rest of the grass is still green and fresh.

These oddly-shaped patches of dead brown grass are seen mostly during the early spring season for warm-season grasses and during early fall for cool-season grasses. When the grass is going through its period of rapid growth, the grubs’ population also experiences a boom. These pests feed on the healthiest patches of grass and, in turn, kill them. 

However, you will start seeing how brown patches might develop in the lawn for a multitude of other reasons as well, such as drought or fungal infections, to name a few. Whatever the cause, it must be addressed as soon as possible.

4. The Lawn Looks Drought Ridden

Lawn Drought Like Symptoms

  • Grubs take water away from the roots
  • The roots are too damaged
  • Grass becomes brittle
  • Lawn turns yellow
Severity of Problem
  • Moderate level problem
  • Neem oil home remedy
  • Insecticidal spray

Sometimes the grass starts looking dry, wilted, and drought-ridden despite regular lawn care and adequate watering. However, this case might need to be clarified because you keep watering your lawn with one inch every week. Also, you keep the sprinklers on for about 20 minutes per session to give the lawn some deep watering.

The reason for this is simple enough, as the grubs’ population tends to suck up all the water and destroy the roots, so the roots cannot absorb it. The condition of the grass will only improve once and unless the grub issue is resolved. Mix a teaspoon of neem oil in one gallon of water and use this DIY home remedy every week to get rid of grubs naturally.

What you must do in this case is to make sure that you put on a pair of thick rubber gloves for protection and then take out a spade or shovel from your tool shed. A rake can also be used but is less effective than a spade or a shovel. Decide at least two parts of your lawn where you want to detect the presence of grubs. Each section should be at a respectable distance from one other and be at least one foot long.

We need to work on one section at a time by digging two inches deep into the soil and then prying it up. Do this along the whole length of your one-foot lawn segment. Once you have turned the sod upside down, look at its underside and count how many grubs you can spot in the topsoil.

5. Sod Is Detaching 

A Consequence of Grub Infestation

  • Grubs eat all the grass roots
  • Grubs destroy the soil
  • Sod is coming off like a carpet
  • Grass starts dying
Severity of Problem
  • The severest level problem
  • Extensive pest control
  • Sod replacement

When lawn grubs begin to eat away the root of your turf grass, the grass will start becoming loose. Even if it looks healthy and lush on the surface, if you grab a handful and pull it up, it will just come out with no resistance. As a result, remember to take a careful look and observe very well at the grass that comes with these loose tufts and notice if they look damaged.

Normally, roots are supposed to look firm and white when the dirt is washed off them. On the other hand, the damaged and grub-eaten roots look soggy, mushy, and brown instead. When you carry out grub control promptly, things get better, and there comes a time when the whole turf becomes detached from the deeper layers of the soil. You can pull the turf from one side and turn it over like a rug, because now it will be easier, as thy will detach easily. 

Again, such extensive damage occurs either from long-term infestation or during the summer and fall periods when the activity of these bugs is at its peak. For an attentive lawn owner, letting your lawn reach this stage should be a big deal.

6. Animal Activity Around The Yard

Increased Wildlife Activity

  • Grubs attracts animals
  • It is a nutritious food source
  • Burrows created by animals
  • Damage to property
Severity of Problem
  • Mild level problem
  • Remove grubs
  • Use a
  • Use animal repellent sprays

When animals get to be activated around the law, then, this is a rather indirect method of determining if you are dealing with a grub pest problem at home. Grubs are a favorite food source for many animals, and they are attracted to a lawn that they infest. Unfortunately, the animals that like to search for grubs attack the lawn at night time and cause damage while they scourge for food.

In this case, the animals that would start to be active would be ones like moles, skunks, skunks, or voles here that will dig through the whole lawn in search of grubs. These animals mostly end up causing more damage to the lawn than the grubs themselves. They will pull out the grass, dig into the soil, go through your trash, and even damage property and utility lines. 

Of course, the fact that you have animals visiting your lawn does not mean that you have a grubs’ infestation. They could be looking for other food sources on the lawn. It helps to know that grubs are their favorite food item, and you must be on guard against them. The next time some mole suddenly starts digging into your lawn at home, your mind needs to go toward grubs immediately.

7. The Soil Is Turning Loose

A Grub Infestation Symptom

  • Grubs burrow into the soil
  • They eat away the roots
  • On walking, the soil will be soggy
  • It will feel soft
Severity of Problem
  • A severe level problem
  • Grub control
  • Lawn treatment


Lawn grubs attacking your yard for a long time will destroy turf grass, other plants, and the very foundations of the lawn. The soil will lose its firmness and turn into a soggy mess. You will notice as if you are walking on a spongy and unstable surface.

This is alarming because these bugs feed on grass and burrow extensively into the soil. The connection between the topsoil and the deeper layer is severed, and water might start accumulating. This water accumulation, in turn, can lead to the festering of diseases and more pests. 

The soil turning loose and the sod detaching are two signs that indicate that the infestation is at its severest point, as it will worsen gradually because the soil is beginning to change and turn weaker. From this point onwards, the longer you take to treat lawn, the more extensive the treatment required will be. Once the integrity of the soil has been compromised, you will have to replace the whole topsoil, which might also include reseeding the lawn again.

8. Seeing Grubs With Your Own Eyes

Visual Evidence of Grubs in Lawn

  • Grubs have taken over the roots
  • They have infested
  • Seeing them vividly
  • Clear on the grass
Severity of Problem
  • A dangerous level problem
  • Spray insecticides
  • Seeding

Once signs and symptoms of grub damage in the lawn become evident, your next step should be to make sure by looking for these pests with your own two eyes. It is time to dig around the lawn and catch these annoying bugs red-handed.

Grub worms are C-shaped, soft-bodied bugs with brown heads and three pairs of feet. They are off-white and are visible in contrast to the dark soil. Experts say that seeing more than five to seven grubs per square foot of the topsoil means dealing with a full-fledged infestation. 

To be 100 percent sure, you must also check out the second patch of lawn. If the same results are seen in that patch, then serious pest control measures must be taken. In this case, the sod has died, and the grass has been destroyed. What you must do, as a result is to clear the whole law, take off the sod, and start seeding from the start. However, you must spray insecticides around, before anything, and then start the seeding process.


Grubs are very common pests to attack lawns in the US, and every lawn owner must deal with them at one point in their life. To control grubs’ population like a pro, you must beware of the following signs:

  • Grubs are the larval stages of white and Japanese beetles, and they feed on the roots of the grass underground.
  • The grass begins to lose density, thin out, and develop discolored circular patches.
  • Once these larvae grubs develop into mature beetles, you can see them flying low over the grass in search of a place to lay more eggs.
  • In extreme cases, grubs kill grass and cause the soil to become soggy and patchy.
  • When you start spotting them out of the soil, it means that the roots have been destroyed, and now is the time to get rid of the old so, and start planting again.

Now, once you know these signs, we hope you will stay vigilant and on the lookout for them as you tend to your lawn. It is easier to prevent grubs than get rid of them because they are persistent pests.

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