Small Holes in Lawn Overnight – Reasons & What to Do Next

Ever wake up one morning to discover small holes in the lawn overnight? Scratching your head quizzically, you look at these tiny circles and silently wonder what type of varmint caused them. Many animals can cause these holes in your backyard. However, before you begin to fill the holes, you first need to know what caused them in the first place.

Generally, holes in your lawn can be caused by animals like gophers, moles, voles, rats, or pest insects such as ground wasps. Burrows can be of various sizes – small holes for insects and larger holes for rodents. In addressing the issue, it isn’t enough to fill the hole and hope it doesn’t return, because it will. You need to identify the cause and then apply the best solution.

What Causes Small Holes in Lawn Overnight?

Small rodents like rats, moles, squirrels, voles, and gophers cause small, rounded holes. The holes will differ depending on what animal is the culprit. Listed below are some common reasons you may see holes in your backyard.

Earthworm Holes

An earthworm is a legless, tube-shaped, segmented worm that can quickly make its dwelling in healthy soil. They use healthy soil because they create tiny holes that will aerate your lawn when they turn it over to feed. 

If there is a great deal of these creatures, you may awaken to many holes in the lawn accompanied by small piles containing granular soil pellets. Usually, these tiny holes are evident at the top of your pile of soil. 

Earthworms are prevalent in fall and spring when the soil is moist. The temperatures are also warmer, which increases earthworm activity. 

Eliminating Earthworms

Avoid, if possible, killing earthworms as they benefit your lawn immensely by aerating it. If muddy castings are an issue, allow them to dry. Once dried, brush it into the grass. Collecting mowing clippings may also reduce earthworm activity on the lawn. 

Vole Holes

Voles generate backyard holes. The best method to diagnose whether the source is a vole is by examining the lawn for certain characteristics. Should you see round rodent droppings accompanied by chewed grass clippings close by the hole, then it is a vole. You may also notice some trails of dead grass.

One thing to note is that field mice may take up residence in holes created by voles. Again, the best thing to do is to look at the droppings. Field mouse waste is oval-shaped.

Eliminating Voles

If you notice voles have taken up residence in your backyard, it is imperative to act immediately. Voles can reproduce very quickly, meaning you may quickly become overrun by invaders. Here are five tips for getting rid of these unwanted guests:

1. Remove Vegetation. This animal doesn’t like to feed in open spaces. The best way to control them is by modifying their habitat. Remove dense ground cover, keep mulch light around your trees and shrubs, and stay on top of snow removal. 
2. Protect Young Trees. Voles often gnaw on young tree trunks. To discourage this and remove their food source, wrap its lower trunk with a guard, like plastic tubing or wire mesh. 
3. Utilize Live Traps. These traps have the purpose of trapping the animal without injuring or killing them. While they may not be the best method for a severe infestation, they will control the numbers or remove a few of the animals. Be sure that before you release them, you remove them as far as possible. Otherwise, they can return to your property.
4. Find a Natural Repellant. Voles do not like the smell and taste of castor oil. Sprinkling a bit of this substance around your landscape will deter them. They also do not like capsaicin which is found in peppers and is what makes them spicy. To get rid of voles naturally, mix some chopped hot pepper with a bit of water. Put biodegradable dish soap in the mixture as well. Spray this on vole hotspots to prevent them from eating plants. There is also an adage that states coffee grinds are useful in repelling voles, moles, and other rodents. However, watch how much is applied. Dumping large amounts can cause the depletion of nitrogen in the soil. This makes it challenging to grow anything. Just place a light sprinkle in places where activity is noted. 
5. Hire a Professional. For fast and effective removal, hire a professional. 

Gopher Holes

Gophers will create dirt mounds and dig holes in a lawn. Since they are vegetarian, you will note damage to any vegetation in your backyard. Gophers will eat blades and roots of grass, and you may find some in their tunnels. Aside from the unsightly holes, the tunnels they dig can affect your lawn’s structural integrity. This will cause an uneven ground level.

Eliminating Gophers

To prevent them from digging, repel them in the same way as a vole – with castor oil pellets. Place these pellets in their holes to drive them out. You can also put peppermint oil or fabric softener sheets inside the burrow to get them to leave, or you can kill gophers using something called “The Giant Destroyer”. 

Mole Holes

A mole will rarely leave an opening to a hole above the ground. These animals feast on grubs plus other soil organisms like earthworms. They tend to dig a tunnel 10” in depth beneath the yard’s surface. 

In terms of holes, they will be a volcano-shaped, raised mound of soil. The height will be up to 24” and the opening will be covered by this mound. These animals are rarely seen on a lawn unless they are mating. 

Eliminating Moles

To prevent them from digging holes, use a natural repellant like Natural Elements Mole and Vole Repellent as it is safe for pets. If the infestation is persistent, plant natural repellants like shallots, marigolds, garlic, daffodils, alliums, or fritillaries to deter this animal. 

Rat Holes

A rat will create holes near fences, tree snags, and large roots. Generally, you’ll see gnawing indicators and soil thrown out of a hole outside the location. The holes are 3” wide and will contain activity near or at the opening. 

Eliminating Rats

Many rat holes indicate an infestation. To eliminate rats and stop the hole production, clear your bushes. Mow overgrown grass, remove any open food source, and apply natural rat repellent like Tomcat Rodent Repellent Granules to the area. 

Squirrels and Chipmunks

Sudden appearances of small holes on your lawn can be an indicator of the presence of squirrels. They can dig up the earth and bury their nuts to store them for later. The Eastern gray squirrel tends to be the major cause. Their holes are small and shallow (about 2 inches in width) without a mound of soil surrounding them. 

If your lawn has nutsedge weed, they may dig small holes to get the tubers for food. 

Chipmunks dig small tunnels and burrows where they hide to remove themselves from danger. These holes are found close to stumps, log piles, and buildings. 

Eliminating Chipmunks and Squirrels

For a squirrel:

• Spread predator urine (fox or coyotes). You may need to reapply regularly.
• Sprinkle cayenne pepper, pepper flakes, chili peppers, and garlic pepper on plants when they are just ready to blossom. After tasting it, the squirrels won’t come back.
• Adding cayenne pepper to bird feeders will deter a squirrel and won’t influence birds.
• Use blood meal.
• Plant marigolds, nasturtiums, and mustard. 

For chipmunks:

• Add hot pepper to bird food to deter chipmunks. It won’t affect birds.
• Pepper plants using hot pepper. It can be done by spraying hot sauce or pepper spray gently around your plant’s base. This method may affect pollinators because capsaicin is toxic for bees. 
• Use mothballs or human hair.
• Use an electronic repellent containing ultrasonic vibrations.
• Eliminate food sources.
• Use humane traps.

Insect Hole

Some insects make their home in the ground during the winter and come out in springtime. This occurs if they are in a larval stage. When they come out, they leave small holes behind. Examples of this included Japanese beetles and cicadas.

The cicada killer wasp and scoliid wasp dig tiny holes where there is short grass and exposed ground. Scoliid wasps dig holes to lay eggs, whereas a cicada killer wasp will use the holes to bury paralyzed cicadas with eggs to feed their young once hatched. 

Termites and ants can dig small holes as well. All that is required is to control them if they cause extensive damage. Otherwise, a bit of activity is normal for a lawn.

Armadillo Hole

If you notice a small hole overnight, it could be caused by an armadillo. This is possible if there are armadillos in your area. They feed on small invertebrates like grubs, or insects such as termites and ants. Their holes are shallow (1-2 inches deep and 6 inches wide) and are used to find food.

To identify if this is the cause, check if there are grubs or ants on the lawn. Ants create small holes with evident ant hills. Grubs will eat grass roots which will cause irregular brown patches of dead grass.

This evidence accompanied by holes may mean there is an armadillo living in your lawn. 

Eliminating Armadillos

The five ways to get rid of armadillos are as follows:

• Eliminate any hiding spots
• Eliminate their food source
• Use in-ground fencing
• Live trapping
• Electric fencing

Bird Holes

If you notice an increase in bird activity, there may be lawn pests present they are feasting on. Ants and grubs will attract birds. You will note birds creating small holes using their claws and beaks. This way, they reveal and can feed on termites, ants, grubs, etc.

Most will begin early in the morning, making it appear as if it happened overnight. 

Eliminating Bird Holes

Fix your lawn from bird holes by controlling insects and grubs in the lawn. Use a good grub filler and rid the lawn of ants to prevent any birds from digging up the grass.

Snake Holes

Sometimes, holes can belong to snakes. These are circular and may contain snakeskin that has been shed close by them. Note that holes are more likely to have been made by other pests and taken over by the snake.

How to Properly Fill the Holes

Fixing the holes depends on the size and how many exist. For one or two, apply topsoil or dirt and place it in the hole using your hand. Press down on it with your foot to make the soil firm. Rake the remaining amount into lawn crevices.

If the hole/ruts are too big and can cause serious lawn damage, use the following approach:

1. Pry any sunken grass up using a flat shovel.
2. Cut your sunken grass into a one-foot square sod using a shovel.
3. Fill the holes with new topsoil.
4. Replace grass sod and press them down using a roller or your foot.

If damage is still too severe, re-establishing the lawn may be required. You will need to begin by using pest control, then tearing out the remaining lawn. Till your yard. Then, lay new sod or plant grass.

Conclusion

There are numerous causes for small holes in the lawn overnight. The most common may be earthworms or insects, and the least likely being snakes. Surprisingly, some pests, like the earthworm, can be beneficial to your lawn, as they aerate it. This may be one of the few times that having a pest is actually a good thing.

Other than that, the holes can be an eyesore and are destructive. Some pests populate very quickly, so you want to be able to identify the source as soon as you can before you end up with a larger problem. By first identifying the pest in question, you can develop a plan of action to eliminate them, then proceed to fill in the holes.

It’s important that, before filling in any hole, you first deal with the pest. This ensures that they don’t return and eliminates the frustration and futility of having to keep filling in holes. In many cases, deterrents are very effective.