Connect with us

Report an Invasive Species

Hoary alyssum

Hoary alyssum

Hoary alyssum

(Berteroa incana)

Priority: -  Contain

Tags: Terrestrial | Toxic

Identification and Reproduction


  • Annual to short-lived perennial
  • Taproot
  • Branches covered in hairs 
  • Leaves are greenish-grey, lower stems are purple 
  • Can over-winter as a rosette, then emerge again in spring
  • Small white flowers, deeply “notched” petals 
  • Shink stalks
  • Seedpods are oval-shaped, have 5-7 black seeds 
  • Stems will grow as high as 0.7 metres 



  • Seeds spread by people, equipment, wildlife

Habitat & Ecology

  • Establishes in sandy and gravelly soils, pastures 
  • Long seed production season 
  • Stems will grow as high as 0.7 metres 


  • Invades forage, range
  • Toxic, harmful to horses, which can be very problematic


  • Removal of entire root crown; burning of mature plant