(Click on thumbnail images to view)

This category include a wide variety of organisms, all of which feed on or in wood, thereby causing damage. All wood borers are best managed by reducing available breeding resources, e.g., by "hot logging" and rapid inventory turnover, or by protecting the wood from entry. Except for ambrosia beetles, economic losses to wood borers have not been quantified. The species listed represent examples of this vast group. For additional information consult the literature.

Coleoptera   Damage by wood boring beetles is caused by the larval stage. The adults do not bore in wood. The only exception is the ambrosia beetles (Coleoptera: Scolytidae and Platypodidae)
Longhorn Beetles or Roundheaded Borers

Coleoptera: Cerambycidae

  Generally fairly large insects. The adults of most species have long antennae, but many common species do not. The wing covers form rather distinct "shoulders", giving the insects a rather characteristic "gestalt". The larvae are white, with a sclerotized head. The thoracic segments are about the same width as the first abdominal segments.

*Whitespotted sawyer

Monochamus scutellatus

Spotted pine sawyer 

M. maculosus

Hosts: Conifers Damage: Attack recently dead conifer timber. Eggs laid in funnel shaped holes chewed in the bark by females. Larvae initiate feeding in phloem, and then enter the wood, making U-shaped galleries. Very common around Prince George throughout the summer. Impact can be severe. Coarse, white wood chips (excelsior) pushed out from the gallery is a characteristic symptom. Monochamus beetles are the most important vectors of the pinewood nematode. 
Northern spruce borer 

Tetropium parvulum

Hosts: Spruce Damage: Important damaging agent of spruce in B.C. Can occur in large numbers. 
*Poplar borer 

Saperda calcarata

Damage on aspen
Poplar borer

Hosts: Mainly trembling aspen, other poplars and willow Damage: Attacks living trembling aspen. Attack sites characteristic with reddish sap running down the bole. Very common around Prince George. Contributes to breakage and decay in aspen. 
Ponderous borer

Ergates spiculatus

Hosts: Douglas-fir and ponderosa pine  Damage: These beetles can be huge. The mouth parts of the larvae of this species gave a logger the idea for the design of the teeth on the chainsaw chain. Not considered an important species. 
"Wasp beetles"

Xylotrechus spp

Hosts: Hardwoods or softwoods, depending on species.  Damage: Attractive, black and yellow or black and white beetles generally not noted in the literature. Destructive in the Okanagan during the last decade. Larvae mine in the wood, packing the galleries with granular frass. 
Ribbed pine borer 

Rhagium inquisitor

Hosts: Mainly pines, other conifers  Damage: This common species does not mine in the wood. It may be a beneficial, destroying bark beetles as it feeds between the bark and wood. The adults have short antennae.

Metallic Woodborers, Jewel Beetles, or Flatheaded Borers 


  These almond-shaped beetles are easily recognized by their shape. Many species have a metallic colour, at least ventrally. The larvae are white, with the thoracic segments notably wider than the abdominal segments

*Golden buprestid

Buprestis aurulenta 

Hosts: Douglas-fir and ponderosa pine, other conifers.  Damage: Larvae enter sapwood immediately, where they may cause considerable damage. Adults are a striking iridescent green or blue-green, with the margins of the elytra bordered with copper. 
*Western cedar borer 

Trachykele blondeli

Hosts: Western red cedar, yellow cypress and incense cedar. Damage: Bore into the heartwood from branches. Galleries packed with frass. 
Flatheaded fir borer

Melanophila drummondi

Hosts: Conifers. Damage: Mostly attacks injured, dead or dying trees, but on occasion will attack apparently healthy trees. The larvae pack their galleries under the bark in a characteristic pattern.
*Sculptured pine borer 

Chalcophora virginiensis

Hosts: Conifers. Damage: The largest species. Does not cause much damage. The elytra have characteristic sculpturing
Bronze birch borer

Agrilus anxius

Hosts: Birch Damage: Attacks and kills weakened or injured trees. Becoming a serious problem in ornamental birch. Expected to become a significant problem in B.C. 

Ambrosia Beetles 

Coleoptera: Scolytidae

  Ambrosia beetles in the families Scolytidae (and Platypodidae) are dominant woodborers in the tropics. In temperate forests only a few species are important. They rely on symbiotic fungi, which provide nourishment for adults and larvae. Unlike other wood boring insects, the damage is caused mainly by the adults.

*Striped ambrosia beetle

Trypodendron lineatum


Cedar attacks

Hosts: Conifers, sometimes hardwoods. Damage: Common species in stored coniferous wood. Extremely important on the coast due to export markets. No structural damage, but characteristic "blackstained" tunnels in the sapwood. A similar species, T. rufitarsus, is also common in the interior. 

Management: While inventory management is still the primary management method, pheromone-based trapping is used for this species and G. sulcatus in B.C. 

*Gnathotrichus sulcatus

G. retusus

Hosts: Conifers. Damage: The former species second in importance to T. lineatum. Galleries often penetrate deeper than T. lineatum and adults can continue boring for up to 2 years. G. retusus can become important in dryer areas. 


Coleoptera: Curculionidae

  Weevils or snout beetles are closely related to bark beetles. The vast majority are easily recognized by their long snout. Many species, however, have short snouts, but are usually stouter than bark beetles. The larvae are similar in appearance and habit to those of bark beetles.

Poplar and Willow Borer

Cryptorhynchus lapathi

 Popular willow damage

Popular willow borer mortality

Hosts: Willow, Poplars (not aspen), and sometimes Alder. Damage: Kills branches and small trees by the larvae's boring in the stem. This widespread, introduced species may be of concern in hybrid poplar plantations etc. Extensive mortality of willow in the Forests for the World and other areas around Prince George. 
Deathwatch Beetles Coleoptera:Anobiidae 

False Posderpost Beetles Coleoptera:Bostrichidae

Powderpost Beetle Coleoptera: Lyctidae

  Many species in the above families cause severe damage to wood in service. Bostrichids are particularly important in the tropics, and are responsible for holes seen in African statuettes etc. Deathwatch beetles get their name from their habit of generating a ticking sound by striking their thorax against the tunnel walls to attract mates. In Mediaeval times, the sound was thought to be an omen of imminent death in the household.

Hymenoptera   Damage is generally caused by the larval stage. The exceptions are carpenter ants and carpenter bees, which utilize wood for nesting but do not feed on it. Adults are free-living, more or less wasp or bee-like insects.
Woodwasps or Horntail Wasps 


  The adults are sturdy, wasp-like insects with a stiff "horn" at the tail, hence the name. Eggs are laid in dead wood. The slightly s-shaped larvae tunnel extensively.

*Blue horntail, 

Sirex cyaneus, and other species 

(Sirex, Urocerusspp.) 

Hosts: Conifer Damage: Circular holes in wood of conifers. A European species (S. noctilio) has been of considerable concern on Monterey pine in Australia, New Zealand and Chile, where it caused mortality due to its associated fungus Amylostereum areolatum. No such damage has been reported in North America. 

Carpenter Ants 

Hymenoptera: Formicidae

  Many species of ants utilize decaying wood to build their nests, thus the damage is caused by the adult insects. Only the carpenter ants cause significant damage, and frequently build their nests in wall voids, decaying beams etc. in homes.

*Camponotus spp.

Carpenter Ants

Hosts: Any kind of wood, usually decayed wood.  Damage: The large ants are important in rotting wood. Often associated with heart rot, and can cause considerable damage in buildings. Also associated with giant conifer aphidsAnts do not feed on wood, and sawdust (cf. termites) pushed out of nest is telltale sign of their presence. 

Isoptera   Termites may cause extensive and severe damage to wooden structures. They are extremely important in warm climates. In B.C., they can be found in coastal areas and in the southern interior. Unlike ants, termites are hemimetabolous, so nymphs resemble the adults. Termites feed on wood aided by symbiotic flagellates (Protozoans). Granular frass (small excrement pellets), rather than sawdust, is symptomatic of their presence.

*Pacific dampwood termite

Zootermopsis angusticollis

Hosts: Any wood in contact with ground  Damage: Important in moist, rotting wood in coastal B.C. Wood can be totally hollowed out without external symptoms. 

Lepidoptera   Damage by wood boring Lepidoptera is caused by the larvae. The adults are moths, which feed on nectar or not at all. 

Carpenter Worms or Goat Moths

Lepidoptera: Cossidae

Aspen carpenterworm,
Female Acossus populi

Hosts: Poplars Damage: The large, cream coloured larvae tunnel in poplars, sometimes causing breakage. 
Clearwing Moths (Lepidoptera: Sesiidae)   Numerous species in hardwoods. Larvae bore in wood, sometimes causing significant damage.



Limnoria lignorum (Phylum Arthropoda, Class Crustacea, Order Isopoda) 

Damage: Resembles wood louse or pill bug. Feed gregariously on marine pilings. May hollow out pilings. 
*Ship worms or teredo, 

Bankia setacea, and 

Teredo navalis (Phylum Mollusca, Class Bivalvia, Order Myoida) 

Damage: Larvae free swimming. Attach to wood and bore in. Holes get progressively larger as individuals grow. The holes are characteristically lined with a hard white calcareous material. Can cause extensive damage to logs stored in salt water for extended periods.