Drywood Termites in New Zealand

Drywood termite Brevis workers

New Zealand has only one species of native drywood termite, Kalotermes brouni. It is the most widespread native termite in New Zealand and the one of most economic importance.

Kalotermes brouni can damage dead, sound wood (fences, power poles and untreated construction timber) and also attack the heartwood of living trees.

Biosecurity New Zealand is also focus on preventing the introduction of the main invasive drywood termite species, West Indian drywood termite and the western drywood termite. 

Native species to New Zealand

  • Kalotermes brouni

Invasive species of concern:

  • Cryptotermes brevis – West Indian drywood termite
  • Incisitermes minor – the western drywood termite

Drywood termites nest in small isolated pockets in the dead wood of living trees and timber in service such as flooring, structural members and furniture.

  • Single-site nesters, meaning they set up inside the timber they are feeding on and do not move except for colonising flights (alates)
  • Small colonies that number in the hundreds of termites
  • The presence of dry, pellet like frass (faeces) with well defined edges, about the size of a seasme seed can be found throughout the gallery system and on horizontal surfaces in close proximity to the infestation. The pellets tend to be light to dark brown, but can darken with age. The pellets of C. brevis tend to be more pointed than native drywood termites but identification is best left to an expert. Often this is the first thing noticed by building owners and pest managers upon inspection.

 

  • Kalotermes brouni workers have a body of approx. 5mm long
  • Kalotermes brouni soldiers have a dark red head with black jaws, together almost as long as their body.

 

  • Soldiers of C. brevis have short thick dark heads, steeply sloping at the front

 

Kalotermes brouni will exploit a wide range of native and exotic timber species. No native species is known to be resistant to Kalotermes brouni attack.

 

  • Unlike other termites, they get their water from the timber they consume and therefore do not require contact with the soil. Because of this fact, their galleries are clean and free of soil (clean apart from the pellet-like frass)
  • Kalotermes brouni that attack the heartwood of t trees can make them completely useless for logging
  • Kalotermes brouni damaging untreated timber in service can be significant. 
  • C. brevis is nominated as one of the world’s most destructive termites mainly based on how successful they have been at hitching a lift in timber around the world and the fact they are a major pest in the USA which accounts for most of the economic loss. There have been reports of infestation in Australia in recent times.

When drywood termite activity is found, the first step is to accurately identify which species is present.

Identification between species can be difficult. The soldiers’ heads and the shape of the frass have subtle differences but better left to a specialist. 

Drywood termites are very difficult to treat as their nests are small, hard to locate and can be spread throughout a structure. For structures, typically fumigation is the preferred option. For smaller item, chemical treatment or heat treatment mat also be options.

Most native drywood termites live their lives in dead tree branches or stumps without ever causing a nuisance. However colonising flights can take hold in power poles and other timber in service

What are drywood termites and what should you do?

Image credit: Auswise Pest Control

More information on types of termites.