Melilotus officinalis

Species category

Agricultural

Common name

sweetclover, yellow sweetclover, ribbed melilot, field melilot, cornilla real, white sweetclover

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

OvalOval:
Broadly elliptic.

Size

  • Length 1.9–2.1 mm
  • Width 1.3–1.6 mm
  • Thickness 0.9–1 mm

Color

Yellow to tan to greenish-tan with some seeds mottled with red and purple

Texture

Dull and smooth

Other structures

HilumHilum:
The scar on the seed coat at the place of its detachment from the seed stalk (funiculus).
is located near the end of the radicleRadicle:
The rudimentary root of the embryo, developing into the primary root after emergence from the seed coat.
. RadicleRadicle:
The rudimentary root of the embryo, developing into the primary root after emergence from the seed coat.
lobe is parallel to the cotyledonCotyledon:
The modified storage leaf or pair of leaves of an embryo and seedling (see primary leaf).
lobe and the end view is symmetric.

Identification notes

Seeds are uniformly ovalOval:
Broadly elliptic.
and symmetric on the edge view (planar). The furrow between the radicleRadicle:
The rudimentary root of the embryo, developing into the primary root after emergence from the seed coat.
and cotyledonary lobe is approximately parallel to the axis of the seed. The uniformity of the seed is because they are borne in a one-seeded podPod:
A dehiscent fruit produced by leguminous plants (beans, peas). Also known as a legume.
. Occasionally, two seeds are formed in the podPod:
A dehiscent fruit produced by leguminous plants (beans, peas). Also known as a legume.
giving each seed a flat side where they were appressedAppressed:
Pressed close or lying flat against something.
. This species has mottled seeds of various amounts. This is the only way they can be distinguished from seeds of M. albus.

Comments

Because the seed is relatively planar, you can flip the seed from side to side and it should appear the same.

Noxious weed seed categories

Not listed

AOSA examination list

Included

Nomenclature

Family

Fabaceae

Valid name

Melilotus officinalis (L.) Lam

Synonyms

Melilotus luteus Gueldenst.
Melilotus arvensis Wallr.
Melilotus officinalis var. micranthus O.E. Schulz

 Melilotus officinalis.  Seeds that are yellow to tan to greenish-tan, with some seeds mottled with red and purple. Photo courtesy of Colorado State University, Department of Soil and Crop Sciences.
Melilotus officinalis. Seeds that are yellow to tan to greenish-tan, with some seeds mottled with red and purple. Photo courtesy of Colorado State University, Department of Soil and Crop Sciences.