Purification and Potency of the Sex Attractant from the Introduced Pine Sawfly, Diprion similis1

The source, bioassay, purification and properties of the sex attractant from the introduced pine sawfly (Diprion similis (Hartig)) (Hymenoptera:Diprionidae) are considered. The alkali-labile attractant from chromatographic purification in amounts as small as 0.004 micrograms attracted 500 to 1,000 males over a 100- to 200-foot distance within 5 minutes. Activity of the attractant in many types of extracts is “masked,” but potency is recovered on column or gas chromatography.