Weed Seed: Peganum harmala (African-rue)
Canadian: Absent from Canada (Brouillet et al. 2016Footnote 1).
Worldwide: Native to desert regions of northern Africa, Asia, and southern and eastern Europe. Introduced to the United States, where it is found across the southwest and Pacific states. Populations are currently concentrated in Arizona, New Mexico and Texas (CFIA 2012Footnote 2).
Duration of life cycle
Seed or fruit type
- Seed length: 2.0 - 4.5 mm
- Seed width: 1.5 - 3.0 mm
- Trigonous seed; shaped similar to an orange wedge
- Seed surface is rough, bubbled and/or covered with reticulations
- Edges of the seed are winged
- Seed is blackish-red to red, translucent
- Hilum is a small hole at one end.
Habitat and crop association
Occurs mainly in dry grasslands and saline waste areas, but also common along roadsides, field edges and in degraded pastures. Prefers disturbed environments (CFIA 2012Footnote 2).
African-rue has long been used as a dye plant and was imported into New Mexico in 1928 for "Turkish Red" dye (Guclu and Ozbek 2007Footnote 3). It has since spread into Texas and Arizona and along the western coast of the United States (Abbott et al. 2007Footnote 4).
Natural spread is mostly by seed, and occurs by water moving over soil or by animals that deposit the seeds in their droppings. Humans also plant this species for medicinal purposes and spread it unintentionally by moving pieces of rootstock with vehicles or machinery (CFIA 2014Footnote 5). African-rue contains alkaloids that are toxic to grazers, including horses, sheep and cattle.
No similar species
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