The carrot family feeds kitchens worldwide and also includes poison hemlock
Carrots, celery, parsley, cumin, coriander and dill all belong to one family, recognisable by flat umbrella-shaped flower heads. So do giant hogweed, whose sap reacts with sunlight to burn skin, and paralysing poison hemlock. It was also the first plant group ever given its own systematic study, back in 1672.
Apiaceae, also called Umbelliferae, holds more than 3,800 species in roughly 446 genera, ranking 16th among flowering plant families. Besides kitchen staples, it includes asafoetida, lovage and sea holly, plus silphium, a famous plant whose identity is uncertain and which may be extinct. Its darker side includes phototoxic species such as parsnip and hogweed and a handful of deadly ones, among them water hemlock and fool's parsley.
Most members are herbs, annual to perennial, often with leaves bunched near the base; a few, like Bupleurum fruticosum, are shrubs. Crushed leaves usually smell, pleasantly or foully. The signature feature is the umbel, a cluster of small five-petalled flowers radiating from one point, usually in compound form. In carrot and coriander, petals on the outer edge grow larger, facing outward. Nectar from the base of the styles draws flies, gnats, beetles, moths and bees, and flowers on one plant often pollinate one another.
Each fruit splits into two single-seeded halves. Many ride the wind, while wild carrot fruits carry bristles, hooked in sanicle, that catch in animal fur. Oily seeds rich in essential oils give anise, cumin and coriander their flavour, and fruit shape and ornament are key to telling species apart.
John Lindley named the family in 1836 after Apium, a word Pliny the Elder used around 50 AD for a celery-like plant. Jacques Daleschamps recognised the group as distinct in 1586, and Robert Morison's 1672 work made it the first plant group with a systematic monograph. Molecular studies since the mid-1990s showed fruit features evolved in parallel many times, upending old classifications; a 2004 proposal split the family into four subfamilies, with Apioideae holding about 90 percent of genera. Pollen fossils date to the Eocene, but the family probably arose in the Late Cretaceous, likely in Australasia.
Source: Apiaceae
