umbels

An umbel is a type of inflorescence in which the floral stalks (pedicels) radiate from a single point at the end of a common stalk, producing an umbrella-like outline. The term is most commonly applied to plants of the Apiaceae (carrot family), though umbels occur in other groups as well.

In a simple umbel, all pedicels arise from the same point on the tip of the main stalk (peduncle). In a compound umbel, the main stalk bears several secondary umbels (umbellules), each with its own set of pedicels; this configuration is characteristic of many Apiaceae species such as Daucus carota.

Many umbels are subtended by an involucre, a whorl or pair of bracts at the base of the inflorescence. Involucres can form a cup or ring around the base; some species lack an involucre altogether.

Flowers in umbels are typically small, actinomorphic, and usually have five petals, often white, yellow, or greenish. They are arranged to attract pollinators, and the fruit type is often a schizocarp that splits into two mericarps.

Prominent cultivated and wild examples include carrot (Daucus carota), parsley (Petroselinum crispum), dill (Anethum graveolens), and coriander (Coriandrum sativum). Umbels bloom mainly in spring and early summer, and they are important for pollinators such as bees and hoverflies. Some members, including Conium maculatum and Cicuta spp., are highly poisonous.

Etymology: The name umbel derives from Latin umbellus meaning little shade, referring to the umbrella-like appearance.