131949 MARSH YELLOWCRESS Rorippa palustris (Brassicaceae) Height to 50cm. Annual of damp, marshy hollows, sometimes growing in shallow water. Stems are upright, angular and hollow. FLOWERS are 3mm across with 4 yellow petals, equal in length to sepals; borne in terminal heads (Jun-Oct). FRUITS are elliptical pods, 4-6mm long. LEAVES are pinnately lobed. STATUS-Locally common throughout, except in N.