Spruce beetles are found wherever there are spruce trees. When the populations start to attack standing healthy trees, spruce beetles can be difficult to detect and manage.
The guidebook Spruce Beetle Management in B.C. includes details on ground detection, prevention, management, hazard rating and risk rating.
Selecting an appropriate management strategy for a spruce beetle infestation will depend on proper detection and a number of site-specific factors.
Spruce beetle infestations are usually located first by aerial surveys, then are surveyed on the ground.
Walkthroughs confirm the previous or suspected identification of beetle and host, collect information to set further survey or management priorities, and estimate population trends.
Probes provide more detailed information than walkthroughs and may be appropriate for laying out treatment areas. These systematic strip surveys provide more precise estimates of attack levels, beetle trends and residual stand values.
Hybrid surveys use aspects of both walkthrough surveys and detailed probing to quickly collect more intensive data than can be collected in a walkthrough only.
Star probes can be used to quickly map the extent of beetle infestations for small scale rapid treatment.
Choice of management strategies will depend on:
After detection, treatment options may consist of a few general tactics: pest reduction harvesting, salvage harvesting, trap trees, prevention and managing spruce beetle on private property.
Pest reduction harvesting maximizes extraction of currently infested spruce trees to reduce the existing population and prevent spread
Salvage harvesting is primarily conducted to recover damaged timber before it loses its economic value
Trap trees are living, large-diameter spruce that are felled to attract spruce beetle, which prefer downed material. Trap trees must be destroyed before the beetles take flight
Restrictions on hauling and storage of infested logs may be necessary
Hazard rating considers stand age, host size, stand density, and elevation. Ratings can be used to set priorities for surveys and treatments, and may be used as a tool in preventive management.
High hazard stands have large susceptible spruce. Details of susceptibility and risk rating can be found in the following documents:
Stand risk is the probability a stand will be attacked or re-attacked based on proximity and to a spruce beetle infestation. Stands with high hazard and risk values have a high priority for management.
The following factsheet provides information on how to manage spruce beetles on private property:
Colour: dark brown to black with reddish wing covers
Size: tiny – four to seven millimetres (about half a centimetre)
Body: hard, stout, cylindrical
Lifespan: usually two years
Destroys: Large-diameter mature spruces, e.g., Sitka. Usually downed trees or debris
Latin name: Dendroctonus rufipennis