Questions and Answers
What is the brown spruce longhorn beetle?
The brown spruce longhorn beetle (BSLB) (Tetropium fuscum) is a wood-boring insect native to northern and central Europe and western Siberia where it typically attacks stressed or dying spruce trees. This beetle does not pose a threat to human health.
Is the brown spruce longhorn beetle in Canada?
Yes. In 1999, BSLB was confirmed in Point Pleasant Park in Halifax, Nova Scotia. In North America to date, BSLB has only been identified in the provinces of Nova Scotia and New Brunswick.
How was the brown spruce longhorn beetle found in Canada?
In 1999, what looked like stressed or dying trees were observed in Point Pleasant Park. The Canadian Forest Service launched an investigation and entomologists identified the BSLB. This was further confirmed by an international expert in the fall of 1999.
How did the brown spruce longhorn beetle get here?
The BSLB likely arrived in Halifax in wood packing material for goods shipped from the insect's native range. Point Pleasant Park is near the port of Halifax's ocean terminals, where wood packing material, such as dunnage, was stored on site.
What effect does the brown spruce longhorn beetle have on spruce trees?
The beetle's larvae feed on the inner bark (phloem) of the spruce tree. Although the entire stem can be affected, the lower portion of the tree is typically the most heavily infested. A spruce tree can be killed if heavily infested with BSLB over a number of years.
How serious a threat is the brown spruce longhorn beetle?
Although BSLB was initially thought to be a serious and damaging pest, recent science indicates it spreads relatively slowly naturally, and may only impact trees that are already stressed from other factors such as drought. Good forest health management practices are therefore important in dealing with pests such as BSLB. Scientific research continues on potential risk-mitigative options as well as management strategies. If this insect spreads and establishes itself more broadly in Canada's spruce forests, it could affect the economic and ecological value of our forest resources, as well as the marketability of spruce products. No hardwood tree species are known to be affected by BSLB.
Does Canada's cold climate limit the pest's spread?
No. The BSLB can withstand Canada's cold climate, although it can take up to two years or more to complete its lifecycle here. In warmer climates, it can complete its life cycle in one season or less.
What does the brown spruce longhorn beetle look like?
The adult beetle is 0.8 to 1.8 cm long with a slightly flattened body that is dark tan, brown or reddish brown with a lighter coloured band visible on some specimens across the shoulder part of the wing covers. The pest's head and thorax are dark brown to black and its legs are brown. The BSLB has compound eyes completely divided into two parts and red-brown antennae about one third to one half its body length.
Is it easy to find adult brown spruce longhorn beetles?
No. Adult beetles are difficult to find because of their appearance and behaviour. Their brown bark like colour is a good natural camouflage. They are more active at dusk, but during the daytime they like to hide under bark scales. However, advances in science have led to better detection methods, such as pheromone based traps that simulate the hormones the insects use to attract mates.
Does the brown spruce longhorn beetle prefer specific types of spruce trees?
In Nova Scotia, the BSLB is known to attack healthy, dying and recently fallen spruce trees (e.g. windfall). This pest has the potential to spread throughout all spruce tree populations including red, white, and black spruce. Other environmental conditions, including drought and the presence of other insect species, may increase a tree's susceptibility to BSLB attack. Although any spruce tree 10 centimetres or more in diameter may be attacked, the beetle tends to prefer mature spruce trees (in excess of 30 cm in diameter at breast height).
Spruce trees are the only known hosts of BSLB in North America.
What are the symptoms of infested trees?
Symptoms may include:
- scattered streams of unexplained resin along the trunk;
- beetle exit holes in the bark about 4 mm across;
- networks of feeding tunnels just under the bark, up to 6 mm across, filled with sawdust like material (frass);
- tunnels, up to 4 cm deep and 6 mm wide, in the wood. These tunnels appear "L" shaped when the wood is cut in a longitudinal section;
- coarse sawdust in and around tunnels or plugging the entrance/exit hole; and,
- progressive yellowing, browning, and loss of needles from portions of the crown.
What measures are in place to control the brown spruce longhorn beetle?
The CFIA is trying to contain and slow the spread of BSLB to other parts of Canada with the help of federal, provincial and industry partners. Regulated areas are often created with restrictions and prohibitions in place where the pest is known to occur, limiting its spread and effect elsewhere. A regulated area can be established through a Ministerial Order, such as the one issued in October 2000 and revised in 2015 that restricts the movement of spruce round logs and firewood out of the province of Nova Scotia.
For more information on the BSLB Risk Mitigation Program developed to control the artificial spread of BSLB, please review the questions and answers developed for industry.
Is tree cutting a part of the management program of BSLB?
No, tree cutting is deemed to be an ineffective strategy to eliminate BSLB and trees are not removed except for research purposes, or for specific site management plans outside of the province of Nova Scotia. The CFIA's is focusing on containing BSLB and supporting continued research, surveillance, effective communications and enforcement activities.
What can I do to help stop the spread of the brown spruce longhorn beetle?
The public can play a key part in helping to control the spread of wood-borne pests by not moving potentially infested materials such as firewood or spruce logs.
- Do not move regulated materials such as firewood out of the infested area without prior written permission from the CFIA.
- Buy firewood locally, burn it on site, and never bring it back home.
- Leave natural items in their natural habitats.
If you are not in an area regulated for BSLB and suspect signs of infestation, within Nova Scotia, please contact the CFIA's BSLB Office toll-free at 1-877-868-0662 or call 902-426-4667. Outside of Nova Scotia, please contact your local CFIA office.
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