Flora of North America species comparison

The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

Cardamine flexuosa

Cardamine oligosperma

wavy bitter-cress, wood bitter-cress, woodland bitter-cress

alpine bitter-cress, few-seed bitter-cress, Idaho bittercress, little western bitter-cress, Siberian bitter-cress
Habit Annuals or biennials; sparsely to densely hirsute basally or throughout, or glabrous. Annuals or biennials; usually sparsely hirsute (at least proximally), rarely glabrous.
Rhizomes

absent.

absent.
Stems

erect, ascending, or decumbent, branched or unbranched, (0.6–)1–5 dm, (slightly flexuous).

(simple or few from base), erect to ascending, (not flexuous), unbranched or branched distally, (0.5–)0.8–3.2(–4.1) dm, usually pubescent throughout or proximally, rarely glabrous.
Basal leaves

(often withered by anthesis), not rosulate, 5–15-foliolate, (2.7–)4–14(–19) cm, leaflets petiolulate;

petiole 0.7–5 cm, (ciliate or not);

lateral leaflet blade oblong, ovate, or elliptic, smaller than terminal, margins entire, repand, crenate, or 3 (or 5)-lobed;

terminal leaflet (petiolule 0.3–1.7 cm), blade reniform, broadly ovate, or suborbicular, 0.5–2.5 cm × 4–30 mm, margins repand, crenate, or 3 or 5-lobed.

(persistent to anthesis), rosulate, pinnately compound, 5–9(–13)-foliolate, 2–8.5(–11) cm, leaflets petiolulate or subsessile;

petiole 1–6 cm;

lateral leaflets petiolulate or subsessile, blade obovate to oblanceolate, smaller than terminal, margins entire or crenate;

terminal leaflet (petiolule 0.1–0.7 cm), blade usually orbicular to ovate, rarely oblong, 0.4–1.5(–2.3) cm × 3–10(–13) mm, base cordate to rounded, margins entire, or crenate-dentate to obscurely 3 or 5-lobed, (surfaces often hirsute, sometimes glabrous).
Cauline leaves

3–15, 5–15-foliolate [leaves (2–)3.5–5.5(–7) cm, including petiole], petiolate, leaflets petiolulate;

petiole base not auriculate;

lateral leaflets similar to basal, (0.4–2.5 mm wide).

3–8, pinnately compound, similar to basal, smaller and fewer distally, petiolate, leaflets petiolulate or subsessile;

petiole 0.5–2 cm, base not auriculate.
Racemes

ebracteate.

ebracteate.
Flowers

sepals oblong, 1.5–2.5 × 0.7–1 mm, lateral pair not saccate basally;

petals white, spatulate, 2.5–4(–5) × 1–1.7 mm; (stamens rarely 4, lateral pair absent);

filaments 2–3 mm;

anthers ovate, 0.3–0.5 mm.

sepals oblong, 1.3–1.8(–2) × 0.5–1 mm, lateral pair not saccate basally;

petals white, narrowly spatulate to oblanceolate, 2.5–3.5 × 0.9–1.5 mm (not clawed);

filaments: median pairs 1.7–2.5 mm, lateral pair 1.2–2 mm;

anthers ovate, 0.3–0.5 mm.
Fruiting pedicels

divaricate or ascending, (5–)6–14(–17) mm.

divaricate-ascending, (2–)3–9(–12) mm.
Fruits

linear, (torulose), (0.8–)1.2–2.8 cm × 1–1.5 mm;

ovules 18–40 per ovary;

style 0.3–1(–1.5) mm.

linear, (torulose), (1.3–)1.6–2.8 cm × 1–1.7 mm; (valves glabrous or sparsely pubescent);

ovules 16–36(–42) per ovary;

style 0.4–1(–1.5) mm.
Seeds

brown, oblong or subquadrate, 0.9–1.5 × 0.6–1 mm, (narrowly margined or not).

brown, oblong, 1–1.6 × 0.8–1.2 mm.
2n

= 32.

= 16.

Cardamine flexuosa

Cardamine oligosperma
Phenology Flowering Apr–Jul. Flowering Mar–Jul.
Habitat Disturbed areas, fields, nurseries, plantations, gardens, flower beds, lawns, roadsides Stream banks, shady banks, creek bottoms, lakeshores, meadows, moist areas, wooded slopes
Elevation 0-1100 m [0-3600 ft] 50-3300 m [160-10800 ft]
Distribution
from FNA
AL; CA; FL; GA; IL; IN; LA; MD; MI; NC; NY; OH; OR; RI; TX; VA; WA; BC; NF; ON; Europe; e Asia [Introduced in North America; introduced also in Mexico, Central America, South America, Australia]
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; CO; ID; MT; NV; OR; UT; WA; WY; BC; Mexico (Baja California)
[WildflowerSearch map]
[BONAP county map]
Discussion

According to J. Lihová et al. (2006), the populations referred to Cardamine flexuosa in North America comprise two taxa of different polyploid origins and evolutionary histories: tetraploid C. flexuosa (2n = 32), native to Europe, and the octoploid taxon informally called “Asian C. flexuosa” (2n = 64), native to eastern Asia. For the latter, the name C. flexuosa subsp. debilis can be used. Nevertheless, these two taxa should be recognized at species level and the correct name for the Asian species should be sought. Based on available data, both taxa occupy the same habitats in North America, but the Asian taxon is much more widespread. The occurrence of European C. flexuosa was, until now, confirmed only for Washington, where both taxa have been recorded. More detailed studies of the North American distributions of both these weeds are needed.

(Discussion copyrighted by Flora of North America; reprinted with permission.)
Source FNA vol. 7, p. 474. FNA vol. 7, p. 479.
Parent taxa Brassicaceae > tribe Cardamineae > Cardamine Brassicaceae > tribe Cardamineae > Cardamine
Sibling taxa
C. angulata, C. angustata, C. bellidifolia, C. blaisdellii, C. breweri, C. bulbosa, C. californica, C. clematitis, C. concatenata, C. constancei, C. cordifolia, C. digitata, C. diphylla, C. dissecta, C. douglassii, C. flagellifera, C. hirsuta, C. holmgrenii, C. impatiens, C. longii, C. macrocarpa, C. maxima, C. micranthera, C. microphylla, C. nuttallii, C. nymanii, C. occidentalis, C. oligosperma, C. pachystigma, C. parviflora, C. pattersonii, C. penduliflora, C. pensylvanica, C. pratensis, C. purpurea, C. rotundifolia, C. rupicola, C. umbellata
C. angulata, C. angustata, C. bellidifolia, C. blaisdellii, C. breweri, C. bulbosa, C. californica, C. clematitis, C. concatenata, C. constancei, C. cordifolia, C. digitata, C. diphylla, C. dissecta, C. douglassii, C. flagellifera, C. flexuosa, C. hirsuta, C. holmgrenii, C. impatiens, C. longii, C. macrocarpa, C. maxima, C. micranthera, C. microphylla, C. nuttallii, C. nymanii, C. occidentalis, C. pachystigma, C. parviflora, C. pattersonii, C. penduliflora, C. pensylvanica, C. pratensis, C. purpurea, C. rotundifolia, C. rupicola, C. umbellata
Synonyms C. flexuosa subsp. debilis, C. flexuosa var. debilis, C. hirsuta subsp. flexuosa, C. scutata subsp. flexuosa C. acuminata, C. hirsuta var. acuminata, C. hirsuta var. bracteata, C. hirsuta subsp. oligosperma, C. hirsuta var. parviflora, C. oligosperma var. bracteata, C. oligosperma var. lucens, C. oligosperma var. unijuga, C. unijuga
Name authority Withering: Arr. Brit. Pl. ed. 3, 3: 578. (1796) Nuttall: in J. Torrey and A. Gray, Fl. N. Amer. 1: 85. (1838)
Web links 
Unless otherwise noted, all data comes from the online version of the Flora of North America, who have made most of their content available via a Creative Commons license (CC BY 4.0).



Type/paste one or more Latin names into the boxes above; matching taxa will show up below the box as you type. You can use the up/down arrow keys to move through the list.

(If the plant you're looking for doesn't show up in the auto-complete list, that means it either isn't described in Flora of North America yet, or it's listed under a synonym. And please note that Flora of North America is still missing several plant families, including Apiaceae, Boraginaceae, and Polemoniaceae.)

Choose a data source: Flora of North America, OregonFlora, UW Burke Herbarium

The species comparison tool is brought to you by:
Northwest Wildflowers