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What is a pappus in members of the Asteraceae family?

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Sunflower — Asteraceae The flowering head of a sunflower (*Helianthus annuus*) is formed of yellow, petal-like ray flowers and a brown center of minute disk flowers.

In the Asteraceae family, the pappus is a highly modified form of the calyx (sepals). Unlike the sepals found in many other plant families, the pappus is typically located at the summit of the ovary and consists of various structures, including dry scales, awns (small pointed processes), or capillary (hairlike) bristles. In some species, these elements may be joined at their margins to form a crownlike ring.12

The pappus serves a critical role in the seed dispersal of the plant's fruit, known as an achene. For example, the capillary bristles found on a dandelion provide buoyancy, allowing the wind to distribute the seeds. In other genera, such as Bidens, the pappus may take the form of barbed awns that enable the fruit to attach to the fur of animals or human clothing, facilitating transport.3