Spring/summer weed in all districts. Annual.
The leaves of many seedlings are purple underneath. The first two leaves are horizontal and narrow, but the true leaves are broad. Has an upright central stem. Its seeds ripen and fall while leaves are still green.
Germinates in spring and dies with frosts in autumn. Grows aggressively in dry conditions. Can grow densely in spring sown pasture. Seeds last for 60 years in the soil and can germinate with little rain. Stock can eat it without serious harm but may suffer scouring and ill-thrift.