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Medicago sativa

Species category

Agricultural

Common name

alfalfa

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

Reniform (kidney shaped) to ovalOval:
Broadly elliptic.
; angular or irregular.

Size

  • Length 2.5–3 mm
  • Width 1.2–1.8 mm
  • Thickness 1–1.2 mm

Color

Yellowish-brown, sometimes with a green tinge

Texture

Smooth to dull

Other structures

HilumHilum:
The scar on the seed coat at the place of its detachment from the seed stalk (funiculus).
 is on concave margin.

Identification notes

The coiled podsPod:
A dehiscent fruit produced by leguminous plants (beans, peas). Also known as a legume.
 of alfalfa produce seeds that are variously compressed and misshapen. Seeds are non-planar and most when viewed from the edge have a slight twist, wave, or bend in the axis. The hilumHilum:
The scar on the seed coat at the place of its detachment from the seed stalk (funiculus).
 "furrow" line is not parallel to the main seed axis. Alfalfa seed color yellowish to tan to brown (immature seeds may be yellowish-green).

Comments

Because the seed usually twists slightly and is non-planar, you can flip the seed over and it should appear different on each side.

Noxious weed seed categories

State Noxious Weed: Arizona 

AOSA examination list

Included

More information

For more information, see ISMA fact sheet.

Nomenclature

Family

Fabaceae

Valid name

Medicago sativa L.

Medicago sativa. Seeds that are yellowish to tan to brown (immature seeds may be yellowish- green). Photo courtesy of Colorado State University, Department of Soil and Crop Sciences.
Medicago sativa. Seeds that are yellowish to tan to brown (immature seeds may be yellowish- green). Photo courtesy of Colorado State University, Department of Soil and Crop Sciences.