20.
Cardamine impatiens
Linnaeus, Sp. Pl. 2: 655. 1753.
Cardamine impatiens
var.
angustifolia
O. E. Schulz
Biennials or, rarely, annuals;
usually glabrous, rarely sparsely pubescent basally.
Rhizomes
absent.
Stems
erect, (angled, sometimes flexuous), unbranched basally, usually branched distally, (1.2-)2-6.5 (-9) dm.
Basal leaves
(often withered by flowering), rosulate, similar to cauline, with fewer distal leaflets.
Cauline leaves
9-24, (9-)13-25-foliolate, petiolate, leaflets petiolulate; petiole 2-6 cm, base auriculate (auricles to 10 × 2.2 mm); lateral leaflets similar to terminal, blade often smaller; terminal leaflet (petiolule to 0.5 cm), blade orbicular, obovate, ovate, or lanceolate, 1-4(-5) cm × 5-17 mm, margins entire or 3-5(-9) -toothed or -lobed.
Racemes
ebracteate.
Fruiting pedicels
divaricate or ascending, 3.5-12(-15) mm.
Flowers:
sepals oblong, 1.2-2(-2.5) × 0.7-1(-1.2) mm, lateral pair not saccate basally; petals (rarely absent), white, oblanceolate, 1.5-4(-5) × 0.6-1.2 mm; filaments 2-3(-4) mm; anthers ovate, 0.3-0.5 mm.
Fruits
linear, (torulose), (1-)1.6-3(-3.5) cm × 0.9-1.5 mm; (valves glabrous or, rarely, pilose); ovules 10-30 per ovary; style 0.6-1.6(-2) mm.
Seeds
brown, oblong, 1.1-1.5 × 0.8-1 mm, (compressed, sometimes narrowly winged apically).
2
n
= 16.
Flowering May-Jul. Streamsides, slopes, roadsides, fields, disturbed areas; 0-200 m; introduced; Ont.; Conn., Ky., Mich., Minn., N.H., Ohio, Pa., Va., W.Va.; Eurasia; introduced also in South Africa.
