|scientific name Dendroctonus rufipennis |
common name Spruce Beetle
Weak, overmature or downed trees with a DBH more than 20 cm.; during outbreaks any spruce tree.
Adults flight period is from late May through July.
The frons of this species has coarse punctures and close granules. Its male genitalia, galleries and host allow it to be distinguished from its closest ally, D. murrayanae.
This species can overwinter in any life stage. Adult hibernation has been given credit for allowing this species to become acclimatized to colder weather. Activity will begin in the spring as the local weather begins to warm. Life cycles can range from 1 to 4 years depending on local climate, a two year lifecycle is most common. Galleries are excavated in the phloem parallel to the grain of the wood. These galleries average between 13 to 23 cm, this species does more engraving than most Dendroctonus species. After the attack mating will occur and oviposition will begin within a week. Approximately 115 eggs will be laid per gallery, egg niches are excavated with longer niches containing more eggs. The eggs are partitioned from the main gallery by frass. Incubation may last up to 4 weeks at higher elevations. The newly hatched larvae will feed in groups and then overwinter. The larvae complete development the following spring and will then pupate for 10 to 15 days. New adults will then emerge and begin to excavate new galleries.
This species is considered a major forest pest throughout its range.
This species feeds on a wide range of Picea spp. throughout its range.
This beetle is found across Canada. It is also found in the US in Alaska, Arizona, California, Colorado, Idaho, Maine, Michigan, Minnesota, Montana, New Hampshire, New Mexico, New Yprk, Oregon, Pennsylvania, South Dakota, Utah, Washington and West Yirginia. It has been introduced in Ireland.
Greg Pohl (2009-09-30)
something wrong with the locality given for the photographed specimen. Also note that this specimen is unusually dark - not a typical rufipennis which is usually more reddish. Might be worth checking the ID on this one.
Greg Goff (2010-03-25)
Not shown on the distrbution map is a epidemic population in & around the Cedar Breaks National Moument & Dixie National Forets in southwestern Utah.
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