Common Names in English: Nodding Groundsel, Nodding Ragwort The
largest family of flowering plants , the Compositae
(Asteraceae), comprising about 1,100 genera and more than 20,000
species and characterized by many small flowers arranged in a
head looking like a single flower and subtended by an involucre
of bracts. A head may consist of both ray flowers and disk
flowers, as in the sunflower, of disk flowers only, as in the
burdock, or of ray flowers only, as in the dandelion. The
Senecioneae are a tribe of closely related genera that can be
recognized most readily by the nature of the pappus and the
involucral bracts or phyllaries. The phyllaries are basically in
one well developed, often partially or wholly connate series of
equal length that closely envelope the head . Frequently there
are a few, very much smaller and mostly randomly distributed,
often necrotic-tipped bracts near the base of the main series.
The pappus is of fine, soft, often pure white capillary hairs .
Heads may be either discoid or radi