Timber infestations

WOOD-BORING INSECTS.

 Common furniture beetle (Anobium Punctatum)

 Otherwise generally known as Woodworm. The Woodworm beetle grows to a size of 2.5 - 5mm long and is usually a brown in colour with a fine yellowish covering.

 The life cycle of the Woodworm starts as a batch of approximately 20 - 60 eggs laid in small groups within cracks, crevices, joints and unprotected wood areas. The eggs can be seen by the naked eye as an oval pearl shape and after about five weeks they begin to hatch, with the larvae emerging from the base of the egg and immediately commencing to tunnel their way into the wood.

 The woodworm larvae (greyish-white in colour) spends its entire life (approximately 2 - 5 years) eating up and down the grain of the wood, in colder weather the rate of tunnelling may be considerably slower than in warmer weather. Around spring time when the larvae is due to mature it will start to bore towards the outside of the wood, stopping just short of the surface, where it will build a pupa chamber and change into a chrysalis.

 After about 6 - 8 weeks the chrysalis opens to allow the adult Woodworm beetle to emerge. After a period of resting to allow the hardening of the shell, wings and etc. the beetle (brown in colour) will bite its way out into the open air, leaving behind an approximate 1.5mm diameter flight hole. The adult fly can start mating within hours of emerging and has a life span of 2 -3 weeks. The female fly will lay her eggs and again the life cycle has started and will continue.

Wood-boring Weevils (Euophryum species and Pentarthrum huttoni)

Otherwise generally known as the New Zealand weevil. The adult beetle grows to an approximate 2.5 - 4.5mm long and is blackish-brown / Redish-brown in colour.

 The adult beetle can be found quite deep within the wood due to it burrowing on its own account.

 The life cycle appears to have two overlapping periods within any 1 year and the adult may live as long as 1.5 years.

Death Watch Beetle (Xestobium Rufovillosum)

 The death watch beetle was formally known as tessellatum, and as and adult beetle it can grow up to 7mm in length. The dark greyish-brown colour with the yellowish scaley hairs make the death watch beetle clearly visible by the naked eye.

 The life cycle of the death watch beetle starts as a batch of approximately 40 - 60 eggs laid in small clusters of 3 -4 within cracks, crevices, joints of rough wood areas. The eggs can be seen by the naked eye as a white pearl shape and after about five weeks they begin to hatch, with the larvae emerging from the egg and immediately commencing to scurry over the wood seeking old exit holes or crevices with which to enter the wood.

 The Death watch beetle larvae (creamish-white in colour) spends its entire life (approximately 3 - 10 years) eating up and down the grain of the wood, in colder weather the rate of tunnelling may be considerably slower than in warmer weather. Around summer time when the larvae is due to mature it will start to bore towards the outside of the wood, stopping just short of the surface, where it will build a pupa chamber and change into an adult beetle. The adult beetle will remain in the pupa chamber until late April, early May time at which time it will eat its way out of the wood leaving an approximate 2.5 mm diameter flight hole and begin its mating.  

Powder Post Beetles (Lyctus)

 There are a number of species belonging to the Lyctus beetle family the most common one being the Lyctus Brunneus.

 The Powder post beetle eggs are long and maggot like, laid in batches of up to 50 in the pores of exposed sectioned woods. When the eggs hatch the young larvae eat there shells and then begin to travel down the pores of the wood eating backwards and forwards in the sapwood, increasing as much as 5 mm long.

 The creamy white larvae of the Powder post beetle gradually reduces the wood to dust, leaving behind a very thin veneer of sound wood on the outside. The flight holes of the Powder post beetle are approximately 1.4mm in diameter.

Longhorn Beetles (Cerambycidae)

There are about 60 species belonging to the Cerambycidae beetle family the most common one being the House longhorn beetle (Hylotrupes bajulus). The adult beetle grows to an approximate 12 - 25 mm long and is greyish-black in colour.

The adult beetle lays its yellowish / greyish-white eggs in cracks and crevices of the wood. After about 3 weeks the eggs hatch into greyish white larvae.

 The larvae varies from about 20 - 40 mm and begins to bore straight into the wood, eventually leaving a thin veneer of sound wood at the surface.

 When the larvae is ready to change to a pupa it eats its way near to the surface of the wood and after about three weeks as a pupa it emerges as a beetle, eating its way out of the wood. The flight hole left by the Longhorn beetle are approximately 3 - 6 mm in diameter.

Other Less Common Species

 The wasp beetle                The basket beetle                The wharf borer            

The wood wasp                 The marine borer                 The shipworm

The gribble

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