Termites in your mango or palm tree? It threatens your house.

Most Australian termites won’t touch a living tree.

Across the rest of Australia, subterranean termite species (Coptotermes, Schedorhinotermes, Heterotermes) are scavengers of dead and decaying wood. A healthy living tree with intact bark and active sap flow is chemically and physically defended — tannins, resins, latex and sap pressure make it un-economic for the colony to attack. Dead stumps, fallen branches and damaged trees are fair game. Living specimens generally are not.

Mastotermes darwiniensis breaks that rule. The Giant Northern Termite — found only in tropical northern Australia, broadly north of the Tropic of Capricorn and concentrated through the Top End — routinely attacks healthy living trees. It has enzymes and gut symbionts that handle live-tree chemistry. Its colonies are enormous, often a million-plus individuals, and they spread across hectares of foraging territory. A mature mango or coconut palm can be killed in a single wet season.

What it eats — the surprising list.

Mastotermes’ appetite is unusually broad. Confirmed targets in Top End properties we’ve attended include: mango trees (the most commonly attacked fruit tree in Darwin), coconut palms, foxtail palms, golden cane palms, citrus (lemon, lime, orange), paw-paws, avocado, banana, mulberry, native eucalypts and bloodwoods, exotic ornamentals (frangipani, plumeria, hibiscus shrubs), garden timber (sleepers, fence posts, decking, garden edging) and — uniquely — rubber, plastic plumbing pipe, soft metals like lead and even some PVC sheathing. Most other Australian termites can’t do half of this. Mastotermes does it routinely.

The economic and ecological logic.

Customers often assume the cheapest path is to cut down the infested tree. It almost never is. Cutting down a Mastotermes-infested mango tree without first eliminating the colony does three things: it costs $1,200–$3,500 in arboriculture; it removes a productive fruit tree that might have another 20 years of bearing left; and — critically — it forces the colony to migrate to a new food source. The colony does not die because the tree is gone. It simply looks elsewhere. The most common new food source it finds is the house.

Treatment is the better path on most accounts. Direct injection of Termidor SC (fipronil) or Premise 200SC (imidacloprid) into the active workings — non-repellent insecticides that termites carry back to the nest and transfer through grooming — combined with a perimeter soil treatment within a 3–5 m radius. The colony collapses. The tree may survive if damage is caught early (caught within one wet season, mango trees in particular recover well); if not, the tree can be removed afterwards without the migration risk.

Indicative 2026 costs — Greater Darwin.

• Single mature mango tree, urban Casuarina/Nightcliff: Direct injection + 3 m perimeter, $480–$780.
• Single coconut palm, Stuart Park / Bayview / Cullen Bay foreshore: Direct injection + access scaffolding for trunk height, $580–$1,200.
• Multi-tree treatment, Howard Springs rural acreage (4–8 trees): $1,800–$4,500 incl monitoring and follow-up inspection.
• Tree removal by arborist (not recommended without prior treatment): $1,200–$3,500 mature tree, plus stump grinding.
• Post-treatment follow-up inspection, 6–12 weeks: $280–$380 included with most treatment quotes.

Worked example — Humpty Doo orchard block.

1 ha block, established orchard with 6 mango trees and 3 citrus, customer noticed mud sheeting on 2 mangoes during April inspection. Inspection identified Mastotermes activity in 2 mangoes and 1 citrus, with the main nest located in a dead bloodwood stump 30 m from the house. Treatment: nest treatment + injection on the 3 affected trees + 50 m perimeter chemical zone protecting the house slab edge — $3,400 incl GST, 10-year colony elimination warranty conditional on annual inspection. Trees recovered. Alternative (removing 3 trees, doing nothing else) would have been $4,200+ and ended with a structural hit on the house in the following wet.

Do termites really attack living trees in Darwin?

Yes — Mastotermes darwiniensis routinely attacks living mango, citrus, eucalypts, palms (coconut, foxtail, golden cane), avocado, paw-paw and exotic ornamentals. This is unusual in Australian termites generally but standard behaviour for Mastotermes.

How can I tell if my mango or palm has termites?

Mud sheeting up the trunk, bracket lesions where bark is missing and wood is hollowed underneath, sudden canopy thinning, frass at the trunk base, and alate swarms emerging at dusk in October–December. Don’t cut the tree down — call for inspection first.

What does tree treatment cost?

Single mature mango or coconut palm: $480–$1,200 depending on size and access. Multi-tree property treatment (4–8 trees): $1,800–$4,500. Tree removal alone is $1,200–$3,500 per tree and doesn’t address the colony — treatment is usually the better economic choice.

Will termites in my tree spread to my house?

Almost certainly if untreated. Mastotermes forages across hectares. We’ve seen properties where a customer cut down an infested tree without treatment; within six months the colony had migrated to the house, causing $40,000+ damage.

Can I prevent it?

Partial prevention: 1.5 m mulch-free zone around trunks, no compost piles against trees, irrigation at canopy edge not trunk, remove dead branches promptly, 6-monthly inspection of significant garden trees as part of property inspection.