UNDER THE NAME ‘XYLOPHAGOUS INSECTS’, MORE COMMONLY CALLED WOODWORM, WE INCLUDE INSECTS WHOSE LARVAE DEVELOP IN WOOD. LONG HORN BEETLE, HESPEROPHANES, LYCTUS, COMMON HOUSE BORER AND DEATHWATCH BEETLE THEIR PRESENCE IS DETECTED MAINLY BY THE EXIT HOLES OF LARVAE WHEN THE REACH THE ADULT STAGE.
HOUSE LONGHORN BEETLES
HOUSE LONGHORN BEETLES
In France, longhorn beetles are very common. Its speciality: laying a hundred eggs in worked softwood (pine, spruce, etc). The development cycle of larvae lasts on average three years during which each of them can bore tunnels in the woodwork, wood panelling and joinery at the rate of 8 to 10 millimetres per day. At the end of its cycle, the larvae transform into insects, from mid-June to the end of August. These larvae are active from 15oC and attack all softwoods.
MAIN SIGNS OF ITS PRESENCE
Holes in the surface of wood, from 8 to 10 mm and oval in shape. Tunnels spread over the surface of the timber, hidden by a thin film of wood curved by the compaction of the ejected bore dust, with ridged walls. Frass is very light beige, in the form of little kegs 0.8 mm long. Faint nibbling sounds.
MAIN CHARACTERISTICS
LARVAE
- Between 28 and 25 mm long.
- Active for several years (average 3 years). Difficult to detect
ADULT INSECT
- From 10 to 20 mm
- Lives 3 to 4 weeks
- Exits Mid-June to end August
- Flies short distances
HESPEROPHANES
HESPEROPHANES
The Hesperophane is a cousin of the Long Horn beetle, but its larvae feed mainly on deciduous wood (oak, beech, etc.).
MAIN SIGNS OF ITS PRESENCE
Parralel tunnels with oval cross-sections over the wood have ridges caused by the insect’s mandibles, similar to the Long horn beetle.
Small kegs of pale yellow bore dust form.
MAIN CHARACTERISTICS
LARVAE
- Between 25 and 30 mm long.
- Cylindrical shape
ADULT INSECT
- From 13 to 24 mm
- Reddish-brown colour
- Comes out of the wood between May and August
- Lives two years or more (shorter life cycle that the Long horn beetle)
THE DEATHWATCH BEETLE
THE DEATHWATCH BEETLE
The larvae of the Deathwatch beetle like wood from structures exposed to humidity or attacked by lignivorous mushrooms.
MAIN SIGNS OF ITS PRESENCE
Circular exit holes of 2 to 4 mm in diameter; Circular tunnels; Granular bore dust in the form of lentils of almost 1 mm in diameter.
MAIN CHARACTERISTICS
LARVAE
- Between 6 and 11 mm long
- Milky white in colour
ADULT INSECT
- Between 5 and 7 mm long.
- Reddish-brown colour.
- Comes out of the wood between April and May
- Lives 1 to 10 years depending on how much the wood has been altered.
COMMON HOUSE BORER
COMMON HOUSE BORER
The common house borer can be frequently found on furniture and antiques.
MAIN SIGNS OF ITS PRESENCE
Round exit holes of 1 to 3 mm; Small piles of finely granular bore dust on the surface of the wood.
MAIN CHARACTERISTICS
LARVAE
- Between 5 and 7 mm long.
- White in colour.
ADULT INSECT
- Between 2.5 and 5 mm long.
- Reddish-brown colour
- Comes out of the wood from May to September
- Lives 1 to 4 years, depending on climatic conditions.
THE LYCTUS
THE LYCTUS
The Lyctus is a beetle that includes two species found in France: the lyctus brunneus, probably of American origin and increasingly widespread; and the lyctus linearis, the European species, which is dying out. The wood must be sufficiently nutritious for the lyctus to take up residence, in other words, full of starch. Chestnut, oak, ash, elm, black locust and any deciduous tropical woods are the preferred targets for the lyctus. This insect usually infests the wood in its first years of use due to the gradual disappearance of the starch.
MAIN SIGNS OF ITS PRESENCE
Circular holes of 1 to 2 mm in diameter; Small cones of very fine bore dust, like very fine flour, fall from the wood without any visible traces of change on the surface of material.
MAIN CHARACTERISTICS
LARVAE
- Up to 5 mm long.
ADULT INSECT
- Between 2.5 and 6 mm long.
- Reddish-brown colour.
- Comes out of the wood from April to September.
- Lives 8 to 12 months.