Plants are very variable vegetatively, but may be recognised by their capitate and involucrate inflorescences that usually have numerous small flowers that are only sometimes subtended by bracts; the outermost flowers of the inflorescence open first and quite often have a flattened, ligulate corolla. The anthers are usually fused and form a tube through which the style extends before the two stigmatic lobes separate and become recurved. The rather small, single-seeded fruits often have a plumose pappus and are then dispersed by wind. Sesquiterpene lactones give the bitter taste of many Asteraceae, e.g. Cnicus benedictus, sometimes used in beer bitters.