Small dirt mounds in yard after rain are common, even in healthy lawns. If useful insects like earthworms and ants cause these mounds, there is nothing to worry about.

Small Dirt Mounds In Yard After Rain Causes

However, burrowers like moles and voles also create mounds of dirt and may destroy the yard altogether.

Learn how to figure out which animal is responsible for the dirt piles in your yard and how to deal with them.

What Causes Small Dirt Mounds in Yard After Rain

What causes small dirt mounds in the yard after rain are earthworms, ants, voles, and moles. In addition to this, even some digger bees or even pocket gophers are ones that would tend to produce small mounds after some rain. 

– Earthworms

Earthworms are an important component of your lawn’s ecosystem because of useful properties such as soil aeration and nitrogen fixation, they are known to be ones that would aerate the soil. These earthworms are attracted to the surface of the lawn after rainfall, which is why you will start seeing them when the rain stops. 

They also serve as a nutritious food source for other influential soil organisms, meaning they add a beneficial component to the soil. The dirt mounds left behind by earthworms are distinct from that of other burrowing animals. These bumps are very tiny and have no holes at their top. If you look close enough, you can spot a hole at the mound’s base from where the worm crawled back into the soil.

Earthworms leave many mounds after each rainfall, but these are only noticeable if you have thinning grass in the lawn, then, it will be quite simpler and easier to spot them. 

– Ants

Ants are the most common culprits regarding large-sized dirt mounds in the lawn. You will be surprised that ant hills have well-defined characteristics compared to other common mounds. They will always have one sound hole right at the top of the hill and almost always have ants hanging around it, this is a common feature that their hills would have, like an entryway. 

However, the problem starts when they start to create and pop up some soil mounds, which would be irregular and have no other opening besides that one central hole at the top. Moreover, they tend to create a very fluffy and smooth-textured home for themselves. They do not home just anywhere on the lawn either. These ant hills almost always emerge near food sources ranging from trees and shrubs to fruits present nearby. 

Ant mounds are not harmful per se and also have pest-repellent properties. After rainfall, they might increase in number to an unbearable degree. Moreover, these ant hills can grow to extreme sizes if left alone.

– Voles

Voles, unlike ants and earthworms, are pests in your lawn and do not contribute much to its health. They are extensive diggers and build an intricate system of underground tunnels over the lawn. These creatures are ones that are prone to use the underground tunnels that they have built for hibernating all through winter.

Extensive rainfall forces these furry burrowers to come out to the top, leaving mounds of dirt behind.

Reasons for Small Dirt Mounds In Yard After Rain

Post-winter and spring season is the most prevalent time in which vole mounds. After a rainy day, these mounds will appear all over the top three inches of the soil. They are barely one to two inches across in diameter and not that high. Poke around these mounds, and you will see rat droppings mixed with the soil. 

– Moles

Mysterious mounds of dirt in the yard with no holes should always alert the possibility of a mole infestation. Mounds created by moles are larger than those created by earthworms and critters. These mounds are volcano-shaped, with neither an entrance hole nor an exit one, they are made by moles. 

Their feature is very specific, as if they have been pushed from deep underground with borders formed of raised soil edges. Moles form these dirt hills in the shaded lawn areas, especially after a particularly rainy weather spell. While removing the dirt from these mounds, you will realize how deep within the soil it has been pushed out, and this is one of the characteristics that they enhance.

Once you see any such mound in the lawn, take immediate action because these animals have the ability to destroy a lawn within weeks. Only a single mole can dig up to 18 feet long tunnels in one hour. Imagine the destruction they can cause to the integrity of your lawn and the foundation of the house if not taken care of promptly. 

– Pocket Gophers

These tiny rodents are often mistaken for moles but produce an entirely different type of infestation altogether. Gophers are natural herbivores and do not prey on insects in the soil. Instead, they like to chew on and ingest roots, underground bulbs, and rhizomes growing in the lawn. After a rainfall, they often burrow back to the surface and leave behind small dirt mounds.

The mounds that would be left behind by gophers are characteristically either half-moon shaped or fan-shaped. This is the key feature that you would see and identify the animal from. 

There will be only one hole in this mound, roughly the size of an average-sized gopher. They use this one hole in the mound both for entry and exit. As is expected, the appearance of mounds and tunneling underground becomes most pronounced during the rainy spring and fall seasons.

What you must do at the sight is to take action immediately if you have identified a gopher infestation from the mounds. Of course, the intricate tunnel system dug by gophers serves to aerate the soil very well. However, they will eat the roots of all the grass and plants in your lawn.

– Digger Bees

Many bees make a home within the soil, including the halictid bees, colletid bees, and andrenid bees. Rain forces them out of the soil, leaving very tiny holes behind. We admit that it can be quite hard to distinguish these from the earthworm mounds in lawns. Both insects tend to make piles of roughly the same size and shape. 

The thing with bees is that they are important pollinators of the ecosystem and cannot be eradicated like useless pests. Do not worry about them destroying the lawn like moles or gophers. We encourage lawn keepers to peacefully coexist with digger bees instead of trying to eradicate them.

How To Get of Dirt Mounds In Yard After Rain?

Get rid of mounds you must start to over seed, ensure you don’t disturb the useful insects, then, get rid of food sources for burrowers. You can use some deterrents to keep the barging animals out, or you may scare them off, lastly, you can even place challenging physical barriers

Moreover, you can even try by increasing the strength of the soil by thickening the grass so that they do no get out. Then take the appropriate measures to prevent larger burrowing animals from digging holes and throwing out the dirt.

– Over Seeding

When you aim to over seeding the lawn at the right time, you will not see earthworms popping up after the rain, because over seeding is what that will solve this problem without disturbing the earthworm population in the soil.

When mounds after rain are created by useful ecosystem components like earthworms, digger bees, and ants, you better not disturb them. Instead, try to hide these mounds by over seeding the grass and making it grow thicker. Make it harder for them to make mounds by planting grass with longer and more extensive roots. 

– Get Rid of Food Sources For Burrowers

When the yard is not kept clean and well-maintained, it attracts all sorts of burrowers. Food sources are the main reasons moles, voles, etc., visit the lawn and create dirt piles. Untidy shrubs and flower beds serve as potential food sources for ants and critters, which means that this is what they will target.

It would help if you kept them trimmed so that no hiding spots remain for them to burrow into the ground. 

Solution for Small Dirt Mounds In Yard After Rain

Make sure to leave your garbage open at night time near the lawn. Most of these animals are attracted to the foodstuff in the garbage can or on the lawn overnight, they won’t harm anything else, they will just get into it.

If there is a bird bath in the lawn, get rid of it, as it is a potential water source for burrowing pests. Grub control is important because many borrowers search for grubs as their food source.

– Use Deterrents To Keep Burrowing Animals Out

Once you begin dealing with soil mounds, the next logical step would be to repel these animals without resorting to animal cruelty. 

It is very difficult to keep small animals from making mounds when plants and vegetables grow in your garden. Take help from plants that rodents and borrowers tend to stay away from nature. Somehow the smell and taste of these are enough to keep voles, moles, and gophers away. We are talking about azaleas, lavender, peony, and daffodils here. 

Moreover, you can aim to use some natural repellents such as cayenne pepper is a natural burrower repellent that can be sprayed all over the lawn or in probable places where you suspect them to be hiding. Simply, you must mix one tablespoon of this spice in one gallon of water and use a spray bottle to sprinkle it all where it is needed. Do this, especially before rainfall, so you do not have to deal with piles of dirt in the yard overnight. 

Other natural ingredients you can go for are coffee and garlic powder mixed with water. Some radical options to try out in extreme cases include coyote urine and fish emulsions. On the other hand, you can even check your local supermarket will have several options regarding chemical rodent repellents. Most are safe pest control options that eliminate ants, etc., without killing them.

– Scare Them Off

One method to keep the larger burrowers at bay is to scare them off when they first visit. This will ensure they do not make a permanent home on your lawn. You can install an automatic sprinkler system that gets activated whenever it senses rodents running around the lawn. 

You can put sonic spike emitters that make ultrasonic noises that terrify the burrowing animals without disturbing family members and neighbors. Not only that, but you can also train pet or guarding dogs and even your house cats to sniff off these animals and scare them off, as they would appear, the animal targeted would directly find a place to hide and run away.

– Put Physical Barriers To Keep Them At Bay

One way to keep burrowing animals from making mounds in the lawn is to keep them out for good. Putting up physical barriers to keep such tiny burrowers, such as gophers and voles, is challenging. Once these barriers are up, you will finally be able to stop worrying about these burrowers damaging your lawn.

Dig a trench all around the periphery of the lawn, which you can reinforce by filling it with stones or a perimeter fence. The underground fence will need to be about 10 to 24 inches deep for deep burrowers like moles and voles.

Flower beds and vegetable gardens attract mounds making animals the most. You can completely seal these off by placing screens on their sides and at the bottom. You may also try to replace the traditional flower beds with raised wooden ones, which is more challenging for them to attack. These are not in contact with the soil and only need screening at the bottom.

Solutions for Small Dirt Mounds In Yard


Dirt piles after each rain spell can be caused by any number of organisms. Here is a brief recap of this detailed guide on this topic:

  • Earthworms and ants are the most common causes behind those piles of dirt after a rain.
  • Burrowing rodents like gophers create slightly larger mounds, moles, and voles forced to come out from underground due to rainfall.
  • Using natural or commercial repellant solutions is the easiest way to keep these burrowers out.
  • You do not need to get rid of useful insects; instead, you overseed the grass regularly.

Today you learned how to identify the different mounds created after rain to the animals responsible for them. We hope you will use this guide to deal with this problem professionally and effectively.

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