Burke: Lepidium didymum vs. Lepidium heterophyllum

	Lepidium didymum	Lepidium heterophyllum
	lesser swinecress, lesser wartcress	purple-anther pepperweed, Smith's pepperweed
Habit	Low, spreading, glabrous to scurfy-pubescent annual, the stems freely-branched, decumbent, 2-5 dm. long.
Leaves	Leaves alternate, numerous, ovate-oblong, 1.5-3 cm. long, pinnatifid, the segments narrow, entire to pinnatifid.
Flowers	Inflorescence of many-flowered, crowded, axillary, bractless racemes 1-4 cm. long; pedicles slender, 1.5-2.5 mm. long; sepals 4, spreading, 0.5 mm. long, deciduous; petals 4, white, linear, minute; stamens 2.
Fruit	Silicles strongly wrinkled, 2 mm. broad and 1.5 mm. long, cordate and notched, inflated and slightly obcompressed.

	Lepidium didymum	Lepidium heterophyllum
Flowering time	May-July	May-June
Habitat	Roadsides, gardens and wasteland.	Roadsides, fields, meadows, pastures, wastelots, and other disturbed ground.
Distribution	Occurring west of the Cascades crest in Washington; British Columbia to California, Arizona, and Texas eastward and northward to the Atlantic Coast. [WildflowerSearch map] [BONAP county map]	Occurring chiefly west of the Cascades crest and in the Columbia River Gorge in Washington; southwestern British Columbia to California, also in scattered locations in the eastern U.S. [WildflowerSearch map] [BONAP county map]
Origin	Introduced from South America (or possibly Eurasia)	Introduced from Europe
Conservation status	Not of concern	Not of concern
Sibling taxa	L. appelianum, L. campestre, L. chalepense, L. densiflorum, L. dictyotum, L. draba, L. heterophyllum, L. latifolium, L. nitidum, L. oblongum, L. oxycarpum, L. perfoliatum, L. ramosissimum, L. sativum, L. strictum, L. virginicum	L. appelianum, L. campestre, L. chalepense, L. densiflorum, L. dictyotum, L. didymum, L. draba, L. latifolium, L. nitidum, L. oblongum, L. oxycarpum, L. perfoliatum, L. ramosissimum, L. sativum, L. strictum, L. virginicum
Web links	Local floras: BC, CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search	Local floras: BC, CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Lepidium didymum

Lepidium heterophyllum

lesser swinecress, lesser wartcress

purple-anther pepperweed, Smith's pepperweed

Habit

Low, spreading, glabrous to scurfy-pubescent annual, the stems freely-branched, decumbent, 2-5 dm. long.

Leaves

Leaves alternate, numerous, ovate-oblong, 1.5-3 cm. long, pinnatifid, the segments narrow, entire to pinnatifid.

Flowers

Inflorescence of many-flowered, crowded, axillary, bractless racemes 1-4 cm. long; pedicles slender, 1.5-2.5 mm. long;

sepals 4, spreading, 0.5 mm. long, deciduous;

petals 4, white, linear, minute;

stamens 2.

Fruit

Silicles strongly wrinkled, 2 mm. broad and 1.5 mm. long, cordate and notched, inflated and slightly obcompressed.

Lepidium didymum

Lepidium heterophyllum

Flowering time

May-July

May-June

Habitat

Roadsides, gardens and wasteland.

Roadsides, fields, meadows, pastures, wastelots, and other disturbed ground.

Distribution

Occurring west of the Cascades crest in Washington; British Columbia to California, Arizona, and Texas eastward and northward to the Atlantic Coast.

[WildflowerSearch map]

[BONAP county map]

Occurring chiefly west of the Cascades crest and in the Columbia River Gorge in Washington; southwestern British Columbia to California, also in scattered locations in the eastern U.S.

[WildflowerSearch map]

[BONAP county map]

Origin

Introduced from South America (or possibly Eurasia)

Introduced from Europe

Conservation status

Not of concern

Sibling taxa