Sulla is a genus of flowering plants in the legume family Fabaceae (subfamily Faboideae), comprising eight species of herbs native to the Mediterranean Basin. The genus ranges across southern Europe, North Africa, and western Asia, where species colonise dry shrubland, bushland, thicket, grassland, and semi-desert habitats typical of the Mediterranean climate.
Plants in the genus are typically herbaceous, with pinnate leaves bearing multiple leaflets and characteristic legume flowers and jointed, spiny fruits. The best-known member, Sulla coronaria (formerly widely placed in Hedysarum as H. coronarium), is a deep-rooted, drought-resistant perennial growing to 1–1.5 m tall, bearing striking red flowers and producing jointed pods with spinulose articles. It has long been cultivated across the Mediterranean region as a fodder crop and for honey production.
Sulla belongs to the order Fabales and shares the nitrogen-fixing root-nodule biology characteristic of the broader legume family, making species ecologically important in maintaining soil fertility in the semi-arid landscapes they inhabit.
Distribution
Sulla species are native to the Mediterranean Basin, distributed across southern Europe (including Italy, Spain, and Malta), North Africa (Algeria, Morocco, Tunisia), and western Asia. They grow in dry Mediterranean-climate habitats including shrubland, bushland, thicket, grassland, and semi-desert.
Ecology
Species of Sulla occupy dry Mediterranean-climate shrubland, grassland, and semi-desert. As legumes they are capable of nitrogen fixation via root nodules, contributing to soil fertility in nutrient-poor habitats. Sulla coronaria is notably deep-rooted and drought-resistant, and its flowers are an important nectar source for honey production.
Cultivation
Sulla coronaria has been cultivated across the Mediterranean region for centuries as a forage plant, valued for animal fodder and hay. It is also grown for honey production, as its flowers attract pollinators. The species' drought tolerance and deep root system make it suited to dryland farming systems.
Taxonomy Notes
The genus Sulla Med. (Medikus, 1787) belongs to the subfamily Faboideae of the family Fabaceae (order Fabales). Several species were historically placed in the genus Hedysarum; for example, Sulla coronaria was long known as Hedysarum coronarium L. The circumscription of the genus has been subject to revision, with some taxonomic treatments recognising fewer species.
