




Description:  The family Asteraceae or, alternatively,  family Compositae, known as the aster, daisy or sunflower family , is a taxon of  dicotyledonous flowering plants. The family name is derived from the genus Aster  and refers to the star-shaped flower head of its members, typified well by the  daisy. The Asteraceae is the second largest family in the Division  Magnoliophyta, with some 1,100 genera and over 20,000 recognized species. Only  the orchid family (Orchidaceae) is larger, with about 25,000 described species.
Plants in the family Asteraceae typically have one or both of two kinds  of florets. The outer perimeter of a flower head like that of a sunflower is  composed of florets possessing a long strap-like petal, termed a ligule; these  are the ray florets. The inner portion of the flower head (or disc) is composed  of small flowers with tubular corollas; these are the disc florets. The  composition of asteraceous inflorescences varies from all ray flowers (like  dandelions, genus Taraxacum) to all disc flowers (like pineapple weeds).