Senecio is one of the largest genera of flowering plants and belongs to the daisy family, Asteraceae.
The family Asteraceae represents the largest family of vascular plants. It contains more than 1500 genera and is widely distributed. In the tropics it occurs in dry areas and on mountains but not in rain forests. A number of food products, including lettuce, chicory and globe artichokes, come from the family. Members of more than 200 genera are used as ornamentals. These include asters, sunflower, chrysanthemums, coreopsis, cosmos, marigolds, dahlias, and zinnias. The ‘flower’ is actually a head of many small specialized flowers that have a head of bracts below them. These smaller flowers may be either disks or ray flowers. The brownish of a sunflower is made up of disk flowers. In these flowers the petals are fused to form a tube. The radiating yellow parts of a sunflower are made of ray flowers. In these, the petals are united into a flattened ray that projects from one side of the flower. Species also may also produce heads of only ray flowers, or of only disk flowers. Dandelion has heads of only ray flowers. Thistle produces a head consisting of only disk flowers. Sepals are reduced to hair-like pappus which may h the mature fruit float away from the parent plant.