Cabbage aphids attacking maturing canolapods. This is a rare species, and tends to occur in small, isolated patches on a few plants on the edges of crops. Turnip and cabbage aphids are rarely seen together on the same plant, but both form characteristically dense clusters on the growing tips. Turnip aphid is the most common species encountered in Western Australian crops. The green peach aphid may be found amongst these heavy infestations, but are more often seen on the undersides of canola leaves during early development, where they remain when the plants flower.
Cabbage aphids are rare, and when found, tend to only occur in small patches near the crop edges.
The green peach aphid attacks other plants including important crops such as lupins, and weeds such as wild radish and wild turnip. Turnip aphid and cabbage aphid also attacks wild radish and wild turnip. Aphids are a similar size and shape to canola flower buds, and can generally be found hidden amongst the heads of canola. Heavy populations can clearly be seen clustered amongst the buds and flowers Damage Aphids multiply rapidly in the mild conditions from late winter to early spring. Favourable weather for aphid build-up usually coincides with budding and flowering times of canola.