Weedscan Weed Profiles

WeedScan is a free community weed identification, alert, recording and communication system that supports cooperative weeds action Australia-wide. The weed profiles are being improved, please send feedback to weeds@invasives.com.au

View the Project on GitHub Centre-for-Invasive-Species-Solutions/demo_json_api

Asteraceae

Berkheya rigida

Common Names: African Thistle

Plant Form: Perennial upright rosette herb or sub-shrub. Size: Up to 80 cm tall. Stem: Upright or spreading, woody, spineless. Leaves: Deeply divided up to 10 cm long, with ends of lobes having sharp spines. Bluish-green upper surface mostly hairless, underside woolly. Margins rolled inward towards midrib. Stem leaves smaller than rosette leaves. Flowers: Clusters of yellow disc-shaped flowers in circular flowerhead. Surrounded by spiny, stiff bracts. Typical thistle type flowers. Fruit and Seeds: Cone shaped and blackish 2-3 mm across. Grow in the spent flowers and topped with tiny scales forming a crown-like structure. Habitat: Scrublands, woodlands, roadsides, dunes, coastal scrub, grasslands. Distinguishing Features: Distinguished from Saffron thistle (Carthamus lanatus) by being perennial and having smaller spiny bracts around the flowerheads.