Northern Prairie Wildlife Research Center
Aquatic and Wetland Vascular Plants of the Northern Great Plains
22. Brassicaceae, the Mustard Family
4. Rorippa Scop. -- Yellow cress
1. Rorippa austriaca (Crantz) Bess. -- Austrian field cress
Stout, erect perennial 3-9 dm tall, from a fleshy taproot, often forming patches
by creeping rootstocks, simple or branched from the base, branched toward the
tip, glabrous to minutely strigose or puberulent on the leaves and stems. Leaves
short-petioled near the base, becoming smaller, sessile and auriculate-clasping
upward, the blades elliptic to oblanceolate, 3-10 cm long, 0.8-4 cm wide, obtuse
to rounded at the tip, irregularly serrate to subentire, unlobed except for
the auriculate-clasping base. Racemes terminal and in upper axils, often
branched. Sepals yellowish-green, 1.5-2 mm long; petals yellow,
2-3 mm long, exceeding the sepals. Siliques rarely producing seed, globose,
1-2 mm long, the persistent style about equaling or exceeding the fruit body;
pedicels spreading or a few recurved, 6-10(15) mm long. Jun--Aug. Low
wet areas in and near fields; uncommon, intro. at scattered points in e and
c ND, e SD and e NE, showing little proclivity for spreading; (Intro. from Europe
and found at scattered localities in the U.S. and Can.).
Previous Species -- Nasturtium officinale R. Br.
Return to Family -- Brassicaceae -
The Mustard Family
Next Species -- Rorippa calycina (Engelm.) Rydb.