How to Determine if a Lawn Has Grubs

How to Determine if a Lawn Has Grubs?

Grubs are ugly tiny insects that can destroy your lawn and attract rabies-ridden animals to your home. To know if you have grubs living within your yard, look for yellow patches of grass, an increase in animal sightings, squishy soil, and grass that can be pulled up easily from the soil.

What are grubs?

Many people have never heard of grub before. When they hear the word grub, the first meaning they think of is the slang word for food like “Let’s go get some grub!” Unfortunately, grubs that live in the soil are not as pleasant as eating delicious food.

Grubs are small white rollie pollie-like insects that enjoy feeding on plants, grass, and other foliage. Although not many insects are nice to look at, grubs are extremely ugly and have large red or orange spots on the top of their heads. 

If you have noticed some drastic changes to your lawn, even though you are treating it well and watering it regularly, it could be that grubs are living underneath the soil and feasting on your lawn, and wasting all of your hard work. But what are the signs that you should look for to know if grubs are in the soil of your lawn?

Signs of grub damage

Below are several signs to look for if you want to confirm if you have grubs within your lawn. Grub damage can spread quickly, and it could spell devastation for your lawn, so search for these signs as soon as you finish reading this article because time is of the essence.

  • Patches of grass will turn yellow or brown, even if you are watering your lawn regularly. If the grass is turning brown, it means that the grubs are eating the grass please and damaging the veins and nutrient system within the blades. If the grass is turning yellow, the grubs have eaten the roots, and now the grass is dying because it can no longer receive any nutrition from the soil.
  • Animals like crows, raccoons, squirrels, and other rodents will dig up your lawn. Grubs are a major part of many forest animals’ diet. These animals can smell grubs through grass and soil, and they will dig them up if they smell them underneath your lawn.
  • If you stand on a patch of grass, the grass slides like a carpet or lifts up onto your shoe. This happens because the roots no longer anchor the grass into place. The grubs destroyed the roots. Watch out because you can easily slip and fall because of the unanchored grass.

When these signs appear, the season of the year is also a major factor in determining if it is grubs destroying your lawns. If all of these signs happen during the early fall to late fall, that means the grubs are growing into adults and doing much more damage than they did when they were larva. 

If you see two or more of these signs, find a yellow patch of grass or a patch of grass that slides away like a carpet and dig into the soil. You do not have to dig more than a few inches before you see ugly white grubs living in the dirt.

Now that you know grubs live in your soil, it’s time to get rid of them.

What to do to fight off grubs

There are a few different ways to fight off grubs, depending on the stage of life the grubs are in. If you are dealing with grub larvae living either within the blades of grass or just below the top of the soil, they will require a different strategy than fighting adult grubs living deep in the earth.

Larvae grubs

When you compare fighting off grub larvae and adult grubs, the larva is the easiest to deal with. Grub larvae live within a few inches of soil, or they live in between the blades of grass, and insecticide, natural or chemical, can kill them easily. Grub larvae usually hatch and live within the topsoil from August and September or the late summer to early fall. As they hatch and move about the soil, brown patches will begin to appear on your lawn.

There are three types of chemical insecticides you can use on your lawn to kill the grub larvae:

  • Neem oil insecticide, which will not kill plants or any beneficial insects
  •  all-purpose chemical insecticide which will destroy anything in its path
  •  grub larvae specific insecticide which kill all the larvae and some other insects

If you have pets that live part of their life outside, do not let them out of the house when you lay down the chemical or grub specific insecticide. They will be fine if you use neem oil insecticide, although they may not like the smell, and they will want to come back into the house to escape the smell.

Adult grubs

If you do not find out that you have a grub infestation in your lawn until they grow into full adults, then expect large parts of your lawn to die because of the grubs. Killing adult grubs is extremely difficult as they can travel faster through the soil and do even more damage.

You can still use insecticides on a heavily infested lawn, but do not expect the insecticide to kill them all. When treating adult grubs with insecticide, the first batch will only kill about 40 to 60% of all the insects. You will also have to remove any mushy soil and replace it with fresh soil once you get the grub infestation under control.


You only have a tiny window of time to fight off grub larvae before they turn into adults and destroy your entire lawn. If you suspect scrubs to be underneath the soil of your lawn after reading this article, don’t waste any time. Inspect your lawn and dig through any mushy soil or anywhere with brown or yellow patches of grass. You can also call an insect exterminator who can treat your lawn for you.