Pseudoturritis turrita

Pseudoturritis turrita (formerly Arabis turrita), the tower-cress, is an erect biennial or short-lived perennial herb in the family Brassicaceae native to the mountains of southern and central Europe, North Africa, and southwest Asia. Plants form a basal rosette of leaves in the first year and produce stiff erect unbranched or sparingly branched flowering stems 30-80 cm tall in the second season, clothed in stellate (star-shaped) hairs throughout. Basal leaves are obovate to oblanceolate, 4-10 cm long, with shallowly toothed margins, narrowing to a long winged petiole; cauline leaves are alternate, sessile, ovate-lanceolate, with deeply auriculate-clasping bases and entire to remotely toothed margins. The inflorescence is an elongate raceme of small four-petalled cream to pale-yellow flowers, each 6-9 mm across. As fruiting proceeds the slender straight to curved siliques (10-15 cm long and only 1.5 mm wide) become characteristically pendulous, drooping all to one side of the stem and giving the plant its tower-like silhouette. Each silique contains a single row of small flattened winged seeds. Flowering takes place from April to June. The species inhabits shaded calcareous cliffs, rocky woodland slopes, ravines, and old walls from lowland to subalpine elevations.