Sagittaria montevidensis

Species category

Flower

Common name

giant arrowhead, California arrowhead, Sagittaire spongieuse

Diagnostic characters

Planting unit

AcheneAchene:
A dry, hard, one-chambered, one-seeded indehiscent fruit, as in buckwheat (Fagopyrum) or sunflower (Helianthus). The fruit wall is not united with the seed coat.

Shape

OvateOvate:
Egg-shaped with basal end the broadest.
with a lateral spikeSpike:
Has a strong central axis (rachis) on which flowers or spikelets are directly attached (sessile), e.g. wheatgrasses.
on apexApical:
The distal end of the fruit or seed away from the point of attachment or attachment scar.

Size

  • Length 2–2.5 mm 
  • Width 1–1.5 mm 
  • Thickness 0.3–0.5 mm 

Color

Light brown

Texture

Stippled 

Other structures

Large marginal wings present.

Identification notes

Unit is compressed with a longitudinal groove on each side.

Noxious weed seed categories

Not listed

AOSA examination list

Not included

Nomenclature

Family

Alismataceae

Valid name

Sagittaria montevidensis Cham. & Schltdl.

 Sagittaria montevidensis.  Achenes with marginal wings and a longitudinal groove on each side. Photo by Julia Scher, USDA-APHIS-PPQ.
Sagittaria montevidensis. Achenes with marginal wings and a longitudinal groove on each side. Photo by Julia Scher, USDA-APHIS-PPQ.