Burke: Asclepias fascicularis

	Asclepias fascicularis
	Mexican whorled milkweed, narrow-leaf milkweed
Habit	Mostly glabrous perennial herbs from rhizomes, the stems 3-8 dm. tall, the juice milky.
Leaves	Leaves mostly whorled and 3-6 per node, the upper often opposite, linear-lanceolate to narrowly oblanceolate, 5-15 cm. long and 3-12 mm. broad.
Flowers	Inflorescence of many-flowered umbels, usually 2 or more in the upper axils, puberulent; peduncles 2-6 cm. long, pedicels 2-15 mm. long; sepals 5, greenish to pinkish-tinged, 2 mm. long, puberulent; corolla lobes 5, 2-4.5 mm. long, pale to dark pinkish-purple; stamens 5, attached to the base of the corolla tube and to each other, forming a column, to which are attached saccate structures 1-2 mm. long, with longer, erect projections; pistil 1, 2-carpellary, the ovaries superior and distinct.
Fruits	Follicles erect, 6-12 cm. long, narrow, smooth.

	Asclepias fascicularis
Flowering time	June-August
Habitat	Sagebrush desert, usually along vernal stream beds.
Distribution	Occurring east of the Cascades crest in Washington; northeastern Washington to Baja California, Mexico, east to Idaho, Utah, and Arizona. [WildflowerSearch map] [BONAP county map]
Origin	Native
Conservation status	Not of concern
Sibling taxa	A. cryptoceras, A. incarnata, A. speciosa
Web links	Local floras: CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria, Turner Photog. WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Asclepias fascicularis

Mexican whorled milkweed, narrow-leaf milkweed

Habit

Mostly glabrous perennial herbs from rhizomes, the stems 3-8 dm. tall, the juice milky.

Leaves

Leaves mostly whorled and 3-6 per node, the upper often opposite, linear-lanceolate to narrowly oblanceolate, 5-15 cm. long and 3-12 mm. broad.

Flowers

Inflorescence of many-flowered umbels, usually 2 or more in the upper axils, puberulent;

peduncles 2-6 cm. long, pedicels 2-15 mm. long;

sepals 5, greenish to pinkish-tinged, 2 mm. long, puberulent;

corolla lobes 5, 2-4.5 mm. long, pale to dark pinkish-purple;

stamens 5, attached to the base of the corolla tube and to each other, forming a column, to which are attached saccate structures 1-2 mm. long, with longer, erect projections;

pistil 1, 2-carpellary, the ovaries superior and distinct.

Fruits

Follicles erect, 6-12 cm. long, narrow, smooth.