Jepson eFlora: Key page
Vascular Plants of California
Key to families | Table of families and genera

Key to Asclepias

View taxon page for Asclepias

(For a list of species in Asclepias, use the above link.)

Jepson Manual glossary definitions can be seen by moving your cursor over words underlined with dots.

1. Leaves ephemeral (stem generally leafless), narrow-linear

2. Hoods exceeded by anther  ..... A. albicans

2' Hoods much exceeding anther head ..... A. subulata

1' Leaves persistent, narrow-linear to wide-ovate or -elliptic

3. Leaves 1 per  (alternate or subwhorled) ..... A. asperula subsp. asperula

3' Leaves > 1 per node (opposite or whorled)

4. Horn 0 or  in hood

5. Hoods not or ± exceeded by anther head

6. Leaf  base clasping stemcorolla dark red-purple ..... A. cordifolia

6' Leaf short-petioled or sessile, blade base rarely clasping stem; corolla green-yellow or white

7. Leaf ±  or  to ± round; corolla green-yellow,  10–15 mm; fruit glabrousprickles 0 ..... A. cryptoceras

7' Leaf  or narrow- to oblong-lanceolate, ; corolla white, lobes 7–8 mm; fruit , with thread-like prickles ..... [A. fruticosa]

5' Hoods exceeded by anther head

8. Stem  to ± ; plant dense-hairy, ± white (appearing woolly at arm's length); tops of hoods exceeding base of anther head (hoods, anther head overlapped) ..... A. californica

8' Stem  (and ± flat); plant ± hairy, green (appearing glabrous at arm's length); tops of hoods exceeded by base of anther head (hoods, anther head not overlapped) ..... A. solanoana

4' Horn  from hood

9. Horn generally exceeding hood ..... A. fascicularis

9' Horn at ± same level as to much exceeded by hood

10. Hoods exceeding anther head by at least 1/2 their lengths

11. Hoods at ± same level as exserted horns, ± , tips rounded ..... A. nyctaginifolia

11' Hoods much exceeding exserted horns, ± ascending, tips  ..... A. speciosa

10' Hoods not exceeding anther head by at least 1/2 their lengths

12. Inflorescences at  sessile or nearly so ..... A. vestita

12' Inflorescences at nodes peduncled

13. Leaves generally broad-elliptic, rarely  to ovate, tip  to  or notched. (Extirpated) ..... A. latifolia

13' Leaves , lanceolate, or ovate, tip obtuse to acuminate

14. Leaves  or , short-petioled to sessile, blade bases  to obtuse, rarely cordate, margins generally not wavy, generally ; hoods exceeded by to at ± same level as anther head; seed 8–9 mm ..... A. eriocarpa

14' Leaves opposite, generally sessile, blade bases tapered to cordate, margins generally ± wavy and/or ± jagged; hoods ± exceeding anther head; seed 10–13 mm ..... A. erosa


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Citation for the whole project: Jepson Flora Project (eds.) . Jepson eFlora, [accessed on ]

Citation for an individual treatment: [Author of taxon treatment] [year]. [Taxon name] in Jepson Flora Project (eds.) Jepson eFlora, [URL for treatment]. Accessed on .

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