Silphium laciniatum

Species category

Weed

Common name

compassplant

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

OvalOval:
Broadly elliptic.

Size

  • Length 11–12 mm
  • Width 9–10 mm
  • Thickness 2–3 mm

Color

Brown

Texture

Rough

Other structures

ApicalApical:
The distal end of the fruit or seed away from the point of attachment or attachment scar.
end is indented.

Identification notes

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.
has no pappusPappus:
Modified calyx in Asteraceae, composed of hairs, bristles, awns, or scales. The pappus-like structure attached to milkweed seeds is termed a coma. 
. Margin winged. A longitudinal bract is attached at base.

Noxious weed seed categories

Not listed

AOSA examination list

Not included

Nomenclature

Family

Asteraceae

Valid name

Silphium laciniatum L.

 Silphium laciniantum.   Achene with an indented apical end.
Silphium laciniantum.  Achene with an indented apical end.