Inula is a genus of roughly 80 species of flowering plants in the family Asteraceae (order Asterales), native to Europe, Asia, and Africa. Members of the genus may be annuals, herbaceous perennials, or subshrubs, ranging from small plants just a few centimetres tall to imposing perennials exceeding 3 metres in height. All share the characteristic composite flowerheads of the daisy family: yellow ray-florets surrounding a central disc, often with conspicuously narrow rays. Technical shared traits include a pappus of bristles, a flat capitulum, and an absence of chaff on the receptacle.
The genus has undergone substantial taxonomic revision in recent decades. Many species formerly placed in Inula — including well-known ones such as Inula britannica, Inula salicina, and Inula helenium — have been transferred to related genera including Pentanema, Pulicaria, Dittrichia, and Limbarda. Under current treatments, the circumscribed genus is considerably smaller than in older literature.
The best-known member is Inula helenium, elecampane, a tall perennial whose stout rhizomes have been used medicinally since antiquity. Several species are cultivated as ornamental garden plants; smaller ones suit rock gardens, while larger, coarse-leaved species work well in mixed borders. Ecologically, Inula species serve as larval food plants for a number of Lepidoptera, including case-bearer moths of the genus Coleophora.
Etymology
The genus name Inula is of uncertain origin and was already in use by Roman writers. The Latin phrase inula campana (field inula) gave rise to the English common name "elecampane" for the species Inula helenium. The specific epithet helenium refers to Helen of Troy; according to tradition, elecampane sprang up wherever her tears fell.
Distribution
Inula species are native across Europe, Asia, and Africa. Individual species occupy a range of habitats within this broad range, from grasslands and meadows to rocky slopes and woodland margins.
Ecology
Inula species serve as larval food plants for several Lepidoptera, notably case-bearer moths of the genus Coleophora, including C. conyzae (recorded on I. conyzae), C. follicularis, C. inulae, and C. troglodytella.
Taxonomy Notes
The genus Inula has been significantly reduced in recent taxonomic treatments. Numerous former members have been reassigned: Inula salicina to Pentanema salicinum, Inula britannica to Pentanema britannica, Inula helenium retained in Inula by some authorities but placed in a sensu stricto Inula, Inula dysenterica to Pulicaria dysenterica, Inula viscosa to Dittrichia viscosa, and Inula crithmoides to Limbarda crithmoides, among others. GBIF currently treats the genus with a narrow circumscription.
