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Striga hermonthica

Species category

Weed

Common name

purple witchweed, witchweed

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

Irregular obovateObovate:
Inverted egg shaped with apical end the broadest.

Size

  • Length 0.3–0.4 mm
  • Width 0.1–0.2 mm
  • Thickness 0.1–0.2 mm

Color

Brown

Texture

Glossy with many longitudinal ridges

Other structures

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

Identification notes

Ridges are large and finely tuberculateTuberculate:
Having small pimple-like protuberances.
 on their rims.

Noxious weed seed categories

State Noxious Weed: Hawaii 
Federal 

Learn more about Striga spp. on ITP's Federal Noxious Weed Disseminules tool.

AOSA examination list

Not included

Nomenclature

Family

Orobanchaceae

Valid name

Striga hermonthica (Delile) Benth.

Synonyms

Buchnera hermonthica Delile
Striga senegalensis Benth.

Striga hermonthica. True seeds with the hilum on the narrow end. Photo by Julia Scher, USDA-APHIS-PPQ.
Striga hermonthica. True seeds with the hilum on the narrow end. Photo by Julia Scher, USDA-APHIS-PPQ.
Striga hermonthica. True seeds with large ridges. Photo by Julia Scher, USDA-APHIS-PPQ.
Striga hermonthica. True seeds with large ridges. Photo by Julia Scher, USDA-APHIS-PPQ.