Ruta L.
Genus of about 11 species, including 3 in North Africa. One of the species with woody branches and stems that sometimes exceed 1 m in height (R. angustifolia); and 2 other herbaceous species that sometimes present somewhat lignified stems at the base in older specimens, they are:
R. chalepensis L. (R. bracteosa DC.) has leaves similar to R. angustifolia, but it is well differentiated by somewhat wider terminal segments, 3-6 mm, petals also fimbriated, glabrous, not puberulent-glandular, with ovate inflorescence bracts (2-7 mm wide), wider than the axillary branches, and with smaller capsules (4-7 mm). Widely distributed throughout the Mediterranean countries, its origin appears to lie in the eastern area, and it seems to have naturalised in the other countries through cultivation since ancient times.
R. montana L. (R. graveolens L. var. montana L.) is well differentiated by its leaves with terminal linear segments, 1 mm or even smaller; glaucous, glabrous, although slightly puberulent-glandular in the inflorescence, and petals with margin entire or slightly undulate, not fimbriate. Capsules small, 1.5-3 mm. This species is rarer than the latter, but still also appears widely distributed throughout the Mediterranean region of Morocco, Algeria and Tunisia.
The rue commonly used for medicinal or veterinary purposes and/or magic potions is usually R. graveolens L., native of the Balkans and Crimea; but it is a poisonous plant that should not be used indiscriminately.
Common and widespread species. Currently, none of the species have been assessed at a global level in the IUCN Red List of Threatened Species.
Key to species
1 Leaves with linear terminal segments, up to 1 mm wide; petals with margin entire or slightly undulate but not fimbriate; capsules small, 1.5-3 mm Ruta montana
1 Leaves with segments 1.6 mm wide, from lanceolate to oblong-obovate; petals with fimbriate margin (resembling long hairs); capsule 4-12 mm long 2
2 Subshrub, stems and branches clearly woody; leaves with segments 1-4 mm wide, capsule 5-12 mm long; branchlets and leaves puberulent-glandular Ruta angustifolia
2 Herbaceous plant, sometimes with somewhat woody base of stems; leaves with segments 3-6 mm wide, capsule 5-12 mm long; branches and leaves glabrous Ruta chalepensis
Updated by: J. Charco.