Pine Sawfly damage on Lodgepole pine
The photograph is courtesy of the family of George Dey. George took many forestry photographs in his forestry career and many are now shown on this web site. Check under ‘Groups’ and George Dey Collection.
A close up view of a Lodgepole pine shoot stripped bare by the larvae of the Pine Sawfly (Neodiprion sertifer). The insects did reach high populations in some Lodgepole pine plantations and although they slowed growth down significantly they very rarely killed more than a few trees in each locality and after a time the populations collapsed. That year’s growing shoots were not usually too heavily attacked as the larvae much preferred the older needles.
Forest Research through John Stoakley who based himself and his colleagues in Lairg for a number of summers was able to bulk up a natural virus or pathogen that attacked the larvae mainly by collecting masses of lavae by hand. The author does not remember the process but does recall the tanks of fairly foul smelling mixture which was somehow refined and some experiments carried out in applying the material via sprays on to the areas newly affected by pine sawfly in an attempt to bring about more rapid population collapse.
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Groups: Animal, Insect, Plant and Fungal species in forestry, George Dey Forestry Collection