COMMON HOUSE BORER EUROPEAN (WOODWORM) Anobium Punctatum
ANOBIUM PUNCTATUM is a pest of major economic importance in New Zealand, the significance of which is not adequately recognised. 3 – 5mm long, dark-brown/black in colour, it is clearly identifiable with the humped (hooded) prothorax which covers the head.
After 2 – 3 years spent tunneling away inside the wood as a larvae (grub), the adult beetles will exit via a round hole 1 – 2mm in diameter. Cutting out this trapdoor is their final wood destroying act. They emerge in order to breed, will not eat any more timber and will die within 3 – 4 weeks.
Exits October – February. Rounded holes 1-2mm. Attacks only soft sapwoods.
When selecting a site for oviposition (egg laying), females appear to recognise the presence of starch in the wood, a vital ingredient for larvae survival. Eggs are NOT laid in starch free wood.
Larvae eat and absorb cellulose only when it is rendered digestible by fungi and micro-organisms present in the wood itself and without which the borer larvae would starve.
Humidity plays a very important part in the incidence of timber infestations. Damp, humid areas create ideal conditions for borer attack.
Most districts of New Zealand provide the perfect climate for borer.
WORST AFFECTED AREAS: CENTRAL UPPER NORTH ISLAND particularly Waikato.
LEAST AFFECTED AREAS: CENTRAL OTAGO. Hot dry climate will not support any significant borer infestations.
World wide distribution of anobium has been effected by man himself. Primarily with the relocation of infested furniture and also the widespread use of untreated softwood timbers right through into the late 50’s and early 60’s
Anobium Punctatum always lays her eggs during the flight season (October – February in New Zealand). Eggs are 0.55mm long and 0.35mm wide. Average number of eggs is 30.
Eggs are always laid in cracks, crevices, end-grain timbers, often into old flight holes, never onto sealed, painted or varnished surfaces.Females may mate 3 times or more during the course of egg laying. Mating normally takes place on the surface. Sometimes this will take place with the female in the hole and the male on the surface.Larvae bore directly into the timber through the bottom of the egg sack. 6mm long when fully grown, larvae will spend 2 – 3 years chewing away inside the wood before eventually working to a position just below the surface (September – October in New Zealand). At this point they hollow out a pupal cavity which allows for the change over from larvae through pupae and into adult beetles, climaxing with the adult beetle cutting out an exit trapdoor onto the surface.The exiting urge is of such magnitude that they frequently gnaw out through paints, wallpapers, varnishes, linoleums, wallboards and plasters. They have also been known to exit through sheet lead and formica.
NEW TECHNOLOGY OF WOOD CONSERVATION
Without doubt Anobium Punctatum was the prime motivator both here in New Zealand and around the world for the establishment of a good sound and reliAnobium larvae are seldom, if ever, found in fresh milled timbers, but require some condition for their development which is not present in wood until it has aged, or in some other way differs from new timber. able timber treatment; helping to place New Zealand among the world’s leaders in the field of timber protection. Ask us how!
|Two Toothed Longhorn.|
|5 – 7 years inside wood.|
|Oval holes 2mm x 6mm.|
|Attacks soft & heart wood.|