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Termites in Mulch: Here’s What you Should Know First

Termites are insects that live in colonies underground. If left unchecked, they can cause significant damage to garden structures, homes, and buildings.

Termites in mulch are a common problem. The only way to get rid of them is to remove the source of their food. They eat mulch. Mulch is woody stuff that has been partially decayed by fungi. So, it is safe to say mulch itself is the biggest attraction to termites. 

There are two types of termite infestations: subterranean and above-ground. Subterranean termites build their nests under the soil, where they feed on plant roots. Above-ground termites build mounds, which look like hills. This type of termite can also cause severe structural damage.

If left unchecked, termites can build entire colonies in mulched areas. Garden and landscaped areas around the home can pose a serious threat to housing structures when overrun by termites.

In this article, we will provide a definitive guide in identifying and treating, and preventing termites in mulch.

Termites in Mulch

Why is there Termites in Mulch

Why do termites go after mulch? Termites will move into mulch and build their colony because the mulch provides a food source for the termites. 90% of mulch is made from wood which is made up of lignin and cellulose.

When ingested by termites lignin and cellulose are broken down into sugars or food.?

Mulch retains heat and provides the ideal temperature of 75?F to 95?F (24?C to 35?C) for termites to thrive. 

These temperatures are also very inviting during seasonal changes such as fall and winter where external temperatures are unsuitable for termites.

How Do Termites Get in Mulch

Termites are subterranean creatures that can live in the soil for their entire life and can easily find their way into mulch if there is no barrier present beneath the mulch layer of soil. Termites will often nest in areas where they feel safe, and they will tend to move into these safe areas when temperatures drop below 75?F.

Termites are cold-blooded creatures and temperature strongly influences their activity. Subterranean termites will not forage in areas where upper-level soil temperatures are either too hot or too cold.

Reticulitermes flavipes

Reticulitermes flavipes, the eastern subterranean termite is the most common termite found in North America. 

Facts About Termites

Is it common to have termites in mulch?

Depending on the mulch that is being used, termites can easily find a welcoming home in mulch. Termites are attracted to the lignin in wood. This lignin when is broken down into sugars when eaten by the termites.

Therefore, wood chips including bark, pine, redwood, and hardwood, if not treated can be an inviting home for termites with a readily available food source

How to Prevent Termites in Mulch

How hard is it to get rid of termites?

Prevention is better than cure and preventing termites in mulch is not such a difficult task.

It is recommended is that some sort of barrier be placed on the soil before mulch is applied. T

his would effectively prevent the upward movement of termites in the soil when the temperatures are no longer favorable.

Effective termite barriers:

Termite barrier

Termite barriers are materials that have been specifically designed to prevent subterranean termites from gaining access to a structure.

Termite membrane barriers

These consist of elastomeric sealants adhered to a high-strength backing. When included in the building envelope, membrane barriers perform multiple functions. In addition to excluding termites and insects, they act as waterproofing, air barrier, and vapor barrier.

Termite sealant materials

are the basic component of termite membranes described above. Sealants are elastomeric, meaning they move with the structure without tearing, and are available in caulk or spreadable formulation. 

How Can you tell When Mulch is Infested with Termites?

When mulch is infested with termites the mulch layer will show signs of their nest which would include boring holes in and around the mulch chips as well as mudded tunnels that they have built for protection and to move around.

Larger, more established colonies will have built mounds from which they could be seen traversing in and out as they carry out their destructive activities.

Another side note is that when mulch is infested with termites they will start feeding on the chips reducing its overall size and as a result, the level or height of the mulched layer will drop.

Close up Termite in Mulch

How to get rid of termites in mulch?

Termites in mulch can be killed both naturally (organically) and Chemically (Using insecticides).

Termites can be killed instantly if they enter mulch that has been treated with an insecticide that will kill them within 24 hours. 

Termites will also detect the poisonous odors within the mulch which will deter them from even venturing close.

Insecticides for termites in Mulch

There are two main chemicals used in Insecticides to kill termites?fipronil and hexaflumuron.

Fipronil is a broad-spectrum insecticide that belongs to the phenylpyrazole chemical family. Fipronil disrupts the insect’s central nervous system. (Wikipedia)

Fipronil is commonly found in Regent it is used against major lepidopteran (moth, butterfly, etc.) and orthopteran (grasshopper, locust, etc.) pests on a wide range of field and horticultural crops.

Hexaflumuron is used as an insecticide specifically against termites. It inhibits the growth of insects because it intervenes in the synthesis of chitin.

Termite bait is an effective insecticide that is applied to wood in order to kill termites. It is usually sprayed on the mulched surface. 

Tips for Applying Insecticide to Mulch –

  • Apply it to the mulch in areas where you suspect they’re living.
  • Apply it in small amounts
  • Spray once every two weeks.
  • Do not use any other pesticides on the same day.
  • Use an applicator that has been designed specifically for this purpose.
  • Spray in a downward motion.
  • Wear protective equipment when applying insecticides.

Traps for Termites in mulch

Cardboard traps –

These traps attract the termites to build their nest on them after which they are removed and burnt.

Before the mulch is applied a cardboard layer can be used in addition to a plastic barrier should be applied before mulch is laid. 

The cardboard can be removed and burnt if there are signed of termites while the plastic barrier will prevent the termites from moving up into the mulch.

Natural Treatments for Termites in Mulch

Mulch that is infested with termites should not be used for landscaping purposes. You may want to remove the mulch and replace it once the termites are gone.

What is a natural way to Repel or Kill Termites?

When it comes to termites we often think that chemicals should be used to drive them away. However, there are some natural repellants that may surprise you and are really effective.

Natural methods to treat termites are:

Exposure to sunlightDirect sunlight will significantly increase the surrounding temperature causing the termites to vacate.
Diatomaceous earthDE powder will work to ensure that all active worker termites crawl through the poison, which will slice their outer shell ensuring rapid dehydration.
NematodesThese microscopic roundworms seek out and enter termites and other insects. They then feed on them parasitically until they die.
Boric acidBoric acid works by dehydrating the termite and shutting down its nervous system
Orange OilThe active ingredient in orange oil treatment is D-limonene which kills termites on contact by breaking down their exoskeleton and destroying their eggs.

These methods are effective when used at the onset of a termite infestation. If the termite colony has been fully established then a more elaborate method is recommended.

Termites in Mulch Pile

Similar to laying mulch in and around vegetable gardens, mulch when stored in a pile can also attract termites.

In such cases, the termite infestation may not be detected until the colony is well established.

Consequently, when this happens, there is a great chance that the mulch, termites and all, will get bagged and shipped. Unfortunately, this can very well end up in your garden. which is why it is always critical that you inspect the mulch for pests before you apply it.

Can Termites be in bags of Mulch?

Depending on where the mulch is stored it can be easy for termites to move into and establish a thriving colony. As a result, the termites can end up in bags of mulch and will live in there until it is laid out in the garden or landscaping.

As mentioned above, close inspection is key in unknowing introducing termites into your garden and living space.

Note: This can have devastating and costly effects if mulch is to be used in gardens close to homes.

What Mulch Attracts Termites?

The type of mulch that will attract termites are:

  • Wood chips
  • Straw
  • Bark chips or shredded bark
  • Cardboard

These mulch all provide a food source for termites as they are all made of the same cellulose material.

If you are interested in a mulch that would not attract termites you can choose those which have been chemically treated, synthetically made, or inorganic mulch

These include:

  • Rubber mulch
  • Plastic mulch
  • Rock mulch
  • Pebbles
  • Larva rocks

Is it bad to put mulch around your house?

Putting mulch around your house may not be such a great idea as it will have the potential to attract termites. Additionally, putting mulch around your house may cause water to pool on the ground, which could lead to mold growth. 

Termites eat wood and cellulose, so if you have a lot of wood products around your home, they could find them quite appetizing. It might seem like a good idea at first but then you?d end up having to spend money fixing the damage.

It is recommended that garden beds and mulch be placed at least 20 ft away from a home. To reduce the instance of having a termite attack on your home.

Garden beds can be placed next to a house if there is proper moisture control in place but it should be done without the use of mulch.

Do Termites Eat Plants?

Termites are insects that feed on wood, but they also eat other plant materials such as grasses, leaves, and even flowers. They don’t usually eat vegetables, fruits, or grains because those foods contain no cellulose.

If you see termites eating plants, it’s likely that they’re looking for food. 

Termites will not eat plants. Termites will prefer dead branches and trees rather than living plants.

As a result, finding them in live trees indicates that part of the tree is already dead. It could be the cambium layer, which is the part of the trunk that’s still growing.

Where can you buy termite bait?

termite bait can be found in leading stores like Walmart, Amazon, and home depot, however, they can also be found in your local agro shop

Do Termites also eat the Soil?

Yes, termites do eat soil. However, they don’t eat the entire soil. They only eat what’s called ?active? soil. Active soil is soil with organic matter that contains cellulose or lignin.

Soils with high levels of active soil are more prone to termite infestation as they can provide a large food source for the colony.

The Takeaway

Termites will live in mulch because it can provide an active source of food. Termites will move into mulch when the temperature of the surroundings is too low or too high for comfort and will prefer a temperature range of between 75?F to 95?F.

Preventative measures for termites will include using a barrier to line the soil before the mulch is applied. Additionally, treated mulch also deters them from venturing close to the mulched areas.

To actively control termites that have already infested a mulched area you can apply pesticides bot organic and inorganic with varying results depending on the level of mulch infestation.

Note:

If you notice any signs of termite activity such as tunnels or nests, contact your local pest control company. They will inspect your property and provide an estimate on how much it would cost to completely eradicate the problem.

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