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Asclepias subverticillata

Species category

Weed

Common name

horsetail milkweed

Diagnostic characters

Planting unit

True seedTrue seed:
A mature fertilized ovule consisting of an embryo, with or without and external food reserve (e.g., endosperm) enclosed by the testa.

Shape

SpatulateSpatulate:
Having a narrow base and rounded apex. Pear-shaped.
 and obovateObovate:
Inverted egg shaped with apical end the broadest.

Size

  • Length: 5 mm
  • Width: 3 mm
  • Thickness: 1 mm

Color

Brown

Texture

Rough, rugulose, and paper-like

Other structures

Margin is winged.

Identification notes

Seed has long, silky basalBasal:
The base of the fruit or seed opposite the apical end.
 hairs, which are usually missing in conditioned seed lots.

Noxious weed seed categories

State Noxious Weed: Hawaii

AOSA examination list

Not included

Nomenclature

Family

Asclepiadaceae

Valid name

Asclepias subverticillata (A. Gray) Vail

Synonyms

Asclepias galioides auct. non Kunth

Asclepias subverticillata. Seeds with long, silky basal hairs, which are usually missing in conditioned seed lots. 
Asclepias subverticillata. Seeds with long, silky basal hairs, which are usually missing in conditioned seed lots.