Termites in the Garden or Fence: Are They Heading for the House?

Finding termites in the garden does not mean they are in your house. However, it does mean that an active termite colony is foraging close enough to have reached your property, making an inspection of your house a priority.

If you find termites in a fence or stump on your property, your first instinct might be to remove the stump, replace the fence or spray the termites yourself. Read on and find out why that isn’t the right move in this situation.

Key Takeaways

• Termites in a stump, fence, tree, or mulch mean an active colony is within foraging range of your property.
• It does not automatically mean your home is infested. It does, however, mean a termite inspection of your home should be a priority.
• Do not remove the stump, replace the fence or otherwise disturb the termites just yet. Disturbing an active termite colony can cause it to abandon its current food source and forage elsewhere, making it more difficult to locate and treat.
• Avoid spraying or poisoning the termites yourself. This can interfere with professional treatment and reduce the likelihood of eliminating the colony.
• It is very difficult to correctly identify the species without specialist knowledge. Some species cause significant structural damage, while others do not attack buildings.

What You Have Actually Found

Termites are not “living in the garden” the way ants are. Subterranean termites live in a central nest and send workers out through underground tunnels to find timber. If you find termites in your garden, you’re usually seeing workers feeding at one end of a much larger colony.

A stump full of termites shows that the nest is somewhere within foraging range. It has probably been there a while, and it has found one food source. Your house is simply another potential food source within the colony’s search radius, which for some Australian subterranean termites can extend at least 50 meters from the central nest.

The good news is that a stump that is actively being eaten is a food source that is not your house. While the termite colony is feeding on a large decaying stump or root system, they are not consuming structural timbers in your home.

Do Not Rip It Out Yet

Removing or grinding out a timber that contains active termites before it has been inspected can create two problems. First, it disturbs the colony’s feeding activity, causing the termites to abandon that food source and establish new foraging routes elsewhere. Second, it removes the very timber that was keeping part of the colony occupied. The next suitable timber they discover could be another stump, a fence, or even your home.

It also destroys valuable evidence. Undisturbed termite workings help a technician identify the termite species and recommend the most effective treatment.

For more information on what to do when you encounter these pests, find out why spraying termites makes it worse rather than better.

Where Termites Turn Up in a Sydney Garden

With mature trees, timber landscaping and favourable moisture conditions, many parts of Sydney are an ideal habitat for termites. These are the places I find activity most often.

• Old tree stumps and root crowns: Decaying stumps and root systems are an excellent food source for subterranean termites. Finding active termites in a stump near your home should always be taken seriously and followed by a professional termite inspection.
• Timber fence posts: Where timber fence posts are in direct contact with the soil, moisture wicks up into the grain and softens it. Termites in a fence show up at ground level first.
• Timber sleepers and retaining walls: Large volumes of timber in direct contact with the soil provide an ideal food source for termites and are often built hard against the house.
• Firewood stacked against the wall: Storing firewood in this way puts a food source directly against your building.
• Deep mulch and raised garden beds: Deep mulch holds moisture in the soil and creates ideal conditions for subterranean termites. When it is banked against the house, it can also conceal slab edges and weep holes, making termite activity harder to detect.
• Buried building timber: Formwork, timber offcuts and pegs left behind during construction can remain underground for decades. I have found active termite colonies feeding on formwork that had been buried beside a slab for more than 20 years.

Does Mulch Attract Termites?

Mulch can attract termites for two reasons. Timber-based mulches contain cellulose and can provide a minor food source, while deep layers also retain moisture in the soil. Together, these conditions create an environment that is favourable for subterranean termites to forage and remain active.

Mulch piled against the building can also conceal the slab edge and cover weep holes. Those few centimetres of exposed brick or concrete are one of the most important areas of the home during a termite inspection, as this is where termite entry is often first detected.

When mulch or raised garden beds cover the slab edge, termites can gain concealed access into the structure. The inspection zone that should have revealed their activity is no longer visible.

If you want to avoid termite problems in your home, keep mulch shallow, keep it away from the wall, and keep the slab edge and weep holes visible. Where mulch or a garden bed sits over the slab edge, it can also bridge a treated zone. 

For more information on termite prevention, find out what a termite barrier actually does.

Can You Tell if They Are the Dangerous Kind?

Generally, no. Australia has more than 350 known termite species, but only a relatively small number are responsible for most structural damage to buildings.

What to Do, in Order

This is what to do if you find termites in your garden, in the order I would want a homeowner to do it.

1. Leave it alone: Do not spray it, poke it, prise it further open, flood it, or remove it. Each of those disturbs the colony and destroys valuable evidence that can help determine the most effective treatment.
2. Photograph what you found: A few shots from a distance offer valuable detail. There’s no need to disturb the colony when taking these pictures.
3. Cover it back up: If you have already pulled the post apart or lifted the mulch, put it back roughly as it was. Termites abandon galleries exposed to light and air.
4. Arrange a termite inspection of the home, not just the stump: A stump full of termites is the reason to look at your home now rather than next year.
5. Let the inspection  guide the treatment: The inspection should identify the termite species where possible, assess the risk to the property, and determine the most appropriate treatment. The infested timber may even be used as part of a baiting or monitoring program before it is removed.
6. Then deal with the stump, the fence, or the sleepers: Removal is still the right long-term answer, once a professional technician has no further use for the infested item.
7. Fix the conditions that attracted them: Take the appropriate steps to ensure termites don’t return.

Making the Garden Less Attractive

Some basic maintenance goes a long way:

• Store firewood off the ground and well away from the house.
• Keep mulch shallow and away from the house so the slab edge and weep holes remain visible.
• Repair leaking taps, blocked downpipes and air conditioner condensate that discharges against the house. 
• Remove buried timber offcuts, old formwork and other construction timber wherever practical.
• Where timber must remain in contact with the soil, inspect it regularly for signs of termite activity.

Then place your property on a regular termite inspection schedule. Australian Standard AS 3660.2, which covers termite management in and around existing buildings, recommends inspections at intervals of no more than 12 months. Properties with a higher termite risk may require more frequent inspections.

Reducing the conditions that attract termites, together with regular termite inspections, gives you the best chance of detecting termite activity before significant structural damage occurs.

Frequently Asked Questions

Are Termites in the Garden a Problem?

Yes, but not for the reason most people assume. The termites in the stump are not damaging your house. However, their presence tells you an active colony is established within foraging range of the building.

Should I Remove a Tree Stump With Termites in It?

Not yet. Removing or grinding an active stump disturbs the colony and removes the food source it is feeding on. It also destroys valuable evidence that helps determine the most appropriate treatment. Have the house inspected first, then remove the stump if recommended.

How Far Can Termites Travel From Their Nest?

Some Australian subterranean termites can forage at least 50 metres from their central nest in search of food.

Does Mulch Attract Termites?

Yes, it can. Timber-based mulches may provide a food source, but the greater concern is that deep mulch retains moisture and, when piled against the house, conceals slab edges and weep holes.

Can Termites Get From the Fence to the House?

Yes, but they don’t actually need the fence to get there. Subterranean termites forage underground and can reach both the fence and your home independently. Finding termites in a fence post doesn’t create a pathway to the house. It simply tells you an active colony is already foraging on your property.

How Do I Kill Termites in My Garden?

Attempting to kill termites in your garden usually backfires. DIY sprays usually kill only the termites you can see, while the rest of the colony continues feeding elsewhere. Disturbing the colony also makes professional treatment more difficult. Read what actually happens when you spray termites before buying anything.

Does Finding Termites Outside Mean They Are Inside?

No. Finding termites in a stump, fence or garden bed does not mean they have entered your home. It does, however, indicate an active colony is close enough to reach your property, which is why a termite inspection should be arranged ASAP.

Is It Safe to Use Firewood That Has Termites in It?

Yes, if you’re burning it. The problem is storing it. Firewood containing termite activity shouldn’t be stacked against the house or left on bare soil while you work through the pile, as it provides an active food source close to the building.

Written by Liam Milligan, licensed pest technician. 25 years in Sydney pest management.

Back to all guides