If you encounter aphids in canola, know that it could be one of several species! The following was kindly offered by Dr. Julie Soroka (Research Scientist Emeritus with AAFC-Saskatoon):
A small survey was conducted in canola in central Saskatchewan in 2014 and 2015 and a few fields were observed with aphids. When found, over 90% of the aphid colonies were turnip aphid (Lipaphis erysimi). Of the remainder, more of the generalist feeder, the green peach aphid (Myzus persicae), was found than cabbage aphid (Brevicoryne brassicae). Interestingly, several of the aphid colonies were infested with the parasitic wasp, Dieretiella rapae!