4.
Rorippa austriaca
(Crantz) Besser, Enum. Pl. 103. 1821. (as Roripa).
Nasturtium austriacum
Crantz, Stirp. Aust. Fasc. 1: 15. 1762;
Camelina austriaca
(Crantz) Persoon;
Cochlearia austriaca
(Crantz) Ledebour;
Myagrum austriacum
(Crantz) Jacquin
Perennials;
(terrestrial or of wet habitat, not submerged, rhizomes thickened, short); usually gla-brous, rarely pubescent proximally.
Stems
(simple from base), erect, much-branched distally, 4-11(-18) dm.
Basal leaves
not rosulate; blade margins pinnatifid.
Cauline leaves
sessile; blade lanceolate, (2.5-)4-12(-15) cm × 5-20(-25) mm, base auriculate to amplexicaul, margins entire or serrate.
Racemes
elongated.
Fruiting pedicels
divaricate-ascending to horizontal, straight, 4-15 mm.
Flowers:
sepals ascending, oblong, 2-3 × 1-1.3 mm; petals yellow, obovate, 3-5 × 1.7-2.5 mm; median filaments 2.3-3 mm; anthers ovate, 0.4-0.6 mm.
Fruits
silicles (rarely produced), straight, globose or subglobose, 2.5-3.2 × 1.5-2.7 mm; ovules 18-40 per ovary; style 1-1.5(-2) mm.
Seeds
biseriate, reddish brown, ovoid, 0.7-0.9 mm, finely colliculate.
2
n
= 16.
Flowering May-Jul. Mud flats, floodplains, fields, roadsides, lakeshores, marshes, ditches, stream banks, wet grasslands, waste grounds; 100-1900 m; introduced; Alta., Man., Sask.; Calif., Conn., Idaho, Ill., Iowa, Nebr., Nev., N.J., N.Mex., N.Y., N.Dak., Pa., Utah, Wash., Wis.; Europe.
