Insects with wood-boring larvae are a major cause of wood-degradation around the world, and within this category there are several major sub-groups which are distinct and described below:.
Monotypic genus of wood boring beetles in the family Cerambycidae (the longhorn beetles) only one species Originating from Europe
Have been spread in timber and wood products, now present in Southern Africa, Asia, the Americas, Australia
The altitude limit is considered to be 1600 m
In 2004, the species was detected in Perth, Western Australia. A containment program was set up and expanded to a full eradication campaign in 2008
Adults are brown to black, hairy, 8 to 20 mm long, with long antenna
Two hairless tubercles on the pronotum are characteristic of the species
On the elytra usually there are two whitish pubescent spots
Polymorphic species, having an extreme variability both in the dimensions and in the aspect
Females have an elongated telson they use to lay eggs in wood cracks
Larvae are creamy white, up to 30 mm long. They have primitive eyes and strong mandibles they use to dig into the wood
Adults are most active in the summer (June–September in the northern hemisphere)
Duration of larval stage 2 to 5 years
Larvae usually pupate just beneath the wood surface and eclose in mid to late summer
When emerging from wood, the adults cut oval exit holes 6–10 mm in diameter
Degrade softwoods only
Powdery frass is visible in the galleries and in the vicinity of the hole
Contrary to the name old-house borer, the species is more often found in new houses - beetles might be attracted by the high resin content of wood harvested less than 10 years earlier
The damage is usually greater if old wood is attacked, as the nutrient content of wood decreases - with age the larva has to consume larger amounts of wood
Larvae are able to go through other materials (plastic, metal)
Adults are reddish brown to black, 13 to 24 mm long, with long antenna
Larvae are creamy white, a bit bigger than EHB, 25 - 30 mm long
Biology and life cycle very similar to EHB
Occur mainly in southern Europe, low economic impact
The galleries and exit holes are a bit bigger than EHB
Attack hardwoods only, usually sapwood (oak, black locust, poplar, beech, walnut tree, …).
The furniture beetle is of European origin and is found mainly in countries with temperate climates
It occurs naturally in the wild in the temperate woodlands of northern Europe and may have colonised other similar temperate environments, particularly in New Zealand and the east coast of North America
It is perceived to be the main cause of damage to timber in the UK over the last 100 years
Adults are small oval brown beetles approximately 4-6mm long
When viewed from above, the head and eyes are invisible beneath the thorax
The surface of the wing covers is covered with fine yellowish hairs and longitudinal rows of pits
The antennae have 11 segments with the last 3 segments enlarged
Larvae are greyish white in colour with a narrow dark band over the mouth parts and grow to about 6mm long
Adults emerge from infected timber in the spring, generally between May and August
Clusters of up to 50 eggs are only laid on wood (in cracks, crevices, exposed end grain or previous emergence holes)
Duration of larval stage 2 to 4 years
When emerging from wood, the adults cut round hole of approximately 1-2mm in diameter
Infest the sapwood of temperate softwoods and hardwoods, but may also infect the heartwood of timbers such as beech, birch, cherry, alder and spruce, or timbers that have been modified by fungal attack
Prefer moist wood (> 14% RH), high moisture levels shorten their life cycle and speed the development of the infestation
Most obvious sign of infestation = accumulation of powdery frass and tiny pellets underneath infested wood or streaming from exit holes
The larvae excavate tunnels approx. 1-2 mm in diameter, generally parallel to the grain of the timber
The tunnels are filled with the residues of the timber consumed, forming a cream-coloured powdery material consisting of lemon-shaped pellets when viewed with a microscope
Most obvious sign of infestation = accumulation of powdery frass and tiny pellets underneath infested wood or streaming from exit holes
This beetle is found in Europe, including the United Kingdom, as well as North America, Corsica, Algeria, and New Caledonia
Its natural habitat is dead or decaying hardwood, or in some cases coniferous wood, especially when the timber has been softened by fungal attack
Adults are brown beetles approximately 6 to 7.5 mm long
The head is largely concealed by a brown thoracic shield
The shield and elytra (wing covers) are dark brown or reddish-brown, with a patchy felting of yellowish-grey short hairs
Larvae are creamy-white with six legs, black jaws, a pair of eyespots on either side of the head, grow up to 11 mm long
Adults emerge in April, May or June, in temperatures above 10 °C
o attract mates, the adult insects create a tapping or ticking sound that can sometimes be heard in the rafters of old buildings on summer nights
Batches of 40 to 80 eggs are laid in crevices in old wood inside buildings, trees, and inside tunnels left behind by previous larvae
Duration of larval stage up to 10 years
When emerging from wood, the adults cut round hole of approximately 2mm in diameter
Degrade softwoods and hardwoods (sapwood or more)
Can develop only in humid wood already infested by fungi, decayed wood is also much easier for the larva of the deathwatch beetle to bore into which allows them to develop at a faster rate
The sapwood is more nutritious and is usually attacked first, followed by heart wood that has been softened by decay.
Oak (Quercus spp.) is the main host, with American oaks being more susceptible than European oaks
The beetle does not infest wood that has recently died; about sixty years must pass for dead oak to reach a suitable condition for attack
These beetles tend to stay on the same piece of wood for several generations until resources are used up and the piece of wood is no longer sufficient
Cause significant damage to wood used in construction in Europe
Are the models used to evaluate the efficacy of wood preservatives according to European standards
The two species are very similar, L. linearis being less common
Native from tropical areas but common everywhere in Europe since more than a century
Adults are brown/reddish, 2.5 to 6 mm long, short antennae, elytra covered with short hair
Larvae are creamy-white with six legs, black jaws, grow up to 5 mm long
Adults emerge between April and August, live 2-3 weeks
Batches of several dozens of eggs are laid in wooden pores (the diameter needs to be > 50 µ)
Duration of larval stage 12 to 18 months depending on the starch content (very short)
When emerging from wood, the adults cut round hole of approximately 1 to 2 mm in diameter
Attack only the sapwood of hardwoods with large pores : oak, chestnut, ash, walnut, black locust, most of the tropical wood species
Wood-based panels can be attacked if made from these wood species
The amount of damage depends on the starch content in the wood
Most obvious sign of infestation = presence of small piles of fine flour-like wood sawdust (or frass) on or under the wood
Large wasps (1 to 5 cm) with a thick waist (adults lack the thin waist found in many wasp species)
Females have a prominent ovipositor (egg-laying apparatus, 'sting') projecting from below the abdomen
Adults are metallic blue-black with some yellow/orange markings
Larvae are creamy white, cylindrical body with a typically dark spine at the rear end
Species: Sirex noctilio, Sirex juvencus, Urocerus gigas
Adults emerge in spring and typically infest fresh killed trees and logs (sometimes living trees), they don’t eat
The female lay eggs in solid wood (through the bark), injecting spores of tree disease-causing fungus Amylostereum areolatum along with a phytotoxic (plant-poisioning) mucus
Larva tunnel in the wood (tunnel is about 5 mm diameter), they live entirely within the host wood or tree
Life cycle is 1-3 years
Sirex sp. and Urocerus gigas attack only softwoods, Tremex sp. attack hardwoods (poplar, willow)
Attack both sapwood and heartwood, producing U-shaped tunnels (up to 20 cm length) tightly packed with course frass
Exit holes and tunnels are circular in cross-section and 3 to 6 mm in diameter.
Occasionally adults emerge through paneling, siding (…) in new houses but do not reinfest processed wood
In Europe, they are not a serious pest of trees or structures
Females are are 15–35mm long, dark, metallic-blue with amber-coloured legs and wings
Males are 13–32mm long, have a blue-black head and front section and an orange abdomen with a dark tip and no 'sting'
Larvae are creamy white and have an obvious head, 3 pairs of very short legs and a segmented, cylindrical body with a typically dark spine at the rear end.
As larvae, woodwasps only eat Amylostereum areolatum, a fungus that the mother deposits into the pine trees with her eggs
Native to Eurasia and Morocco, sirex wood wasps were accidentally introduced to the southern hemisphere, including Australia (since 1961), New Zealand (1900), South Africa (1994), South America (Uruguay 1980) and more recently North America (found in NY in 2004).
Sirex noctilio is the most damaging invasive pine plantation pest in the southern hemisphere, killing millions of pine trees. Trees die as the fungus spreads, disrupting the tree's vascular system.
Sirex noctilio certainly has the potential to devastate pine plantations across the U.S. In South American plantations growing North American pines, tree mortality sometimes exceeded 80%.
Quarantine pest in the US, can be transported through wood packaging materials
Prevent its arrival in a country: inspection of all goods that are likely to harbor the pest at ports of entry. Until 2004, this was successful at preventing S. noctilio from becoming established in the U.S.
Control the spread of the insect within the country:
Proper forest management (removing damaged and diseased trees)
Remove dead trees infested with Sirex woodwasps and chip or burn as soon as possible
Nematode Deladenus siricidicola
Parasitoid wasps Rhyssa persuasoria