Volunteer oilseed rape
Brassica napus
Importance
A problem wherever oilseed rape is grown. Can be difficult to control in many situations, especially in vegetable brassicas.
1. Kidney-shaped cotyledons usually blue-green in colour, often with a reddish or purplish tinge.
2. First leaves oval in shape with shallow indentations along edges. Later leaves are waxy and long and increasingly notched or irregular.
3. Mature plant very familiar, particularly when in flower.