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Ants in Mulch: Simple Prevention, Removal and Mulching Tips

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Mulch is used as a protective barrier between the ground and growing plants. It helps keep water off the roots and prevents weeds from sprouting, and this is an ideal place for ants to nest.

Ants will be attracted to mulch because they will be sheltered enough to build their nests. It provides a form of warmth from colder temperatures and protection from prey. Smaller insects living within the mulch and topsoil will also become a food source for the ants, making it an inviting area to colonize.

Mulch provides an inviting environment for ants to nest in. They like the moist, sheltered conditions that are created by the mulch.

In this article, we will explain why ants find refuge in mulch, along with the simple methods you can implement to prevent and remove ants if you are laying new mulch or already have a mulched area that has ants.

Why Are Ants Attracted to Mulch?

Ants in Mulch

When worker ants leave their nest to search for food or shelter, they leave behind a trail of pheromones (chemical scents) — like leaving a trail of breadcrumbs to help you find your way home. After an ant finds food or shelter, it turns around and follows a different pheromone trail back to the nest.

This will leave a beacon trail for other ants to find their way into your mulched area, which is often a safe haven for ants if the necessary measures are not taken to keep them out or make them feel less safe.

They will sometimes walk quite far from their nests, using their antennae or other senses to find a suitable food source and a safe place to nest.

When an ant nest is destroyed in your premises or close by, unknowingly to you, they will scout the area in search of shelter and food. Mulch provides this shelter and a source of food from decaying mulch or wood.

How to Get Rid of Ants in Mulch?

One way to get rid of ants in mulch is by using a strong, non-toxic pesticide that kills both adults and larvae.

The most common methods of removal include:

Mulch Evenly

Applying mulch evenly at a thickness of 2 – 3 inches over the intended area will effectively prevent ants from making mulch their home.

A thin layer of mulch will allow sunlight to pass through, causing the area to become heated and preventing ants. 

Addtionally, rain and water from watering plants will also easily soak through, causing any potential nests to become soggy and uninhabitable by the ants, prompting them to leave.

Apply Neem Oil

When used on mulch, neem oil can prevent pests by turning off insects’ feeding hormones and acts as a repellant. This is done by the active ingredient Azadirachtin present in the oil. Neem oil can be applied as a soil drench or a spray twice a week for effective results.

When used as a drench, the mulch will absorb the active ingredient, Azadirachtin.

Drenching is the process of adding diluted control products directly to the mulch.

Having the solution of neem oil directly in the soil would act as a first defense repellant for any laying insects venturing close to where it is applied.

Use Citrus Peels or Orange Oil

Orange oil and Citrus Peels are natural insecticides that will help keep pests away.

The constituents of orange oil are mainly limonene, citral, and perillyl alcohol. They have a strong smell and can be used to deter pests such as whiteflies, aphids, ants, beetles, caterpillars, and other insects.

The easiest method to use orange oil on plants is to fill a spray bottle with water and add 1-2 tablespoons of orange oil.

Then spray the mixture on the leaves of plants twice a day, once in the morning and once in the evening. 

Sticky Bait

Sticky baits are very effective in organically getting rid of ants.

They work best when you put them on the ground under ant trails or near their nests. You should use them only if you don’t want to spray pesticides.

You can use sticky bait such as sugar syrup, honey, molasses, peanut butter, etc.

Make sure the bait is not too sweet and sticky so that ants won’t eat it.

Once ants start venturing towards the sticky bait, they’ll follow the bait’s scent, eat it, and become trapped and die.

Use Insecticides

Outdoor sprays such as Phantom or Termidor are very effective at killing carpenter ants. 

As worker ants discover the bait, they share it with the rest of the colony to eliminate them all.

Types of Ants in Mulch

Argentine ants are common in the southeastern USA and California, among others listed below.

  • Carpenter ant
  • Fire ant
  • Pharaoh’s ant
  • Sugar ant
  • Thief ant
  • Harvester ant
  • Blackhouse ant
  • Odorous house ant

The carpenter species of ants are one of the most common species of ants found living in mulch.

The Carpenter Ant (Camponotus pennsylvanicus) is a species of ant native to the eastern United States. Carpenter ants prefer damp wood, nesting in rotting tree stumps, firewood, wood fencing, and mulch.

Carpenter ants are nocturnal, meaning that they are active at night. This doesn’t mean that they are not during the day.

The ants will move constantly and colonize a section of mulch in a very short time.

How to Identify Carpenter Ants in Mulch

These ants can be identified by their black bodies with yellowish-orange bands around the abdomen. They have two large mandibles (jaws) that help them cut into the wood. Their antennae are long and slender with a reddish tip.

Carpenter Ants Nesting

It is one of only two ants in North America that are not social, and it has been called “the oddest” ant.

Its colonies consist of a single queen who reproduces by budding off new queens. These queens mate with males in the springtime.

When mature, the western black carpenter ant colony contains about 10-20,000 workers, with large colonies of more than 50,000 individuals. There is usually only one functional, wingless queen per colony.

Carpenter ants’ nests are recognizable by the small piles of wood chips that you’ll see around their entrances. You may also see bits of dead ants and discarded swarmers too.

Will Ants Damage Mulch?

Carpenter ants love wooden things, and the number of wooden objects around your house can encourage or deter them.

Ants aren’t known for eating wood, but they build nests out of wood, from things including gardening shears, wooden handles, and even birdhouses!

Can Ants in Mulch Harm Plants

Ants in mulch will not harm plants because they don’t feed on wood. Instead, they use wood or mulch chips as shelter.

Ants do little damage to plants, although they can disturb the soil around plant roots and deposit it on the surface during their nest-building activities. This can be an issue on lawns where low-growing plants are buried by excavated soil. They may also disturb plant roots in pots and containers. source

When the ants burrow their way into the soil, they will create channels and air pockets that can cause a problem when watering. 

These channels can cause water to run freely out of the soil and will not allow the water to be adequately absorbed into the soil.

As a result, the plant will suffer from the effects of underwatering.

On the flip side, They also eat insects, which helps keep pests away from plants.

If you see ants in mulch, there’s probably nothing wrong with your garden. But if you notice ants building a nest near your plants, it may be necessary to remove the nest before it becomes too big.

How to Prevent Ants in Mulch and Landscaping

If you suspect that you’ve got a carpenter ant infestation, you’ll first want to ensure that you don’t accidentally disturb their nests.

This could lead to a much bigger problem down the road. Once you’ve found their hiding place, you’ll want to take steps to prevent them from returning.

The easiest way to keep carpenter ants out of your home is to maintain a clean yard and clear up debris regularly.

Remove fallen tree limbs, leaves, and other items that might provide shelter for the insects. Keep grass mowed short and weed-free, and cut weeds near your house.

Finally, the thickness of mulch applied around plants should be kept between 2 to 3 inches. Any thicker than this will create a “safe space for ants to nest.

Additionally, applying a repellant can irritate the ants in their search for shelter and nesting.

There are many types of ant repellants available, including:

Soap

• Vinegar

• Citronella oil

• Peppermint oil

• Orange Oil or Peels

• Neem Oil

Repellants should be applied directly on top of the mulch as a spray where the ants are likely to find shelter once per month.

Anti Bug Mulches

A chip or bark mulch is made from cypress or cedar trees and is very helpful for repelling bugs. Both cypress and cedar contain natural chemicals and oils like thujone that deter insects like ants.

The wood of these trees is also resistant to decay, allowing it to last longer than other mulches.

Does Mulch Attract Other Insects?

They live underground in damp soils near rotting wood, mulch, debris or concrete slabs, or on plant roots.

During the winter and colder temperatures, they usually migrate to warmer areas which can very well be in the comfort of mulch.

Insects fall prey to birds and other larger animals. Mulch will provide an effective hiding spacing for ants, not-to-mention camouflage, as the mulch color sometimes comes very close to mulch.

In such a background or backdrop, ants can go unnoticed for a long period of time until their colony is well established.

Well-established colonies will require more drastic measures for removal.

How to Mulch Without Inviting Pest 

Mulching can be simple, but it is important to ensure it is laid properly to deter pests.

The best way to mulch without inviting insects is to use cedar chips because the odorous chemical it emits will deter pests from making it their home.

Another good way to prevent or deter pests is to even out the area before mulching. This ensures that when the mulch is applied, its thickness is uniform, and there are no large dips where the mulch is thick enough to provide shelter for nesting.

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