During flowering, it has 10-millimetre-long bright red-orange flowers. This species produces a large number of seeds and, left untreated, a few plants can take over an area to form an almost solid carpet. Its yellow summer flowers are followed by seed pods filled with tiny, reddish-brown or black seeds. The leaves appear green with a pinkish-red outer (see photo).
Control
In newer lawns a 2,4-D, mecoprop and dicamba mixtures can provide control. Spot treatment with a non-selective herbicide can be used to kill established plants.