Family: Amaranthaceae

Achyranthes aspera (chaff flower, devil’s horsewhip) is a shrub native to Africa and Asia. It is known for its medicinal benefits, however can cause nausea and vomiting and should be avoided in pregnant women and men undergoing fertility treatment. It is reported to be widely naturalized on Oʻahu, Maui, Lanaʻi, Molokai, Hawaiʻi Island and Kamole (Laysan Island). This plant has spiny seeds that stick to clothing, gloves and animals, and forms a persistent seed bank. Dense stands of it can be difficult to walk through, and it can be a host of the tomato weed curl virus. These qualities make chaff flower undesirable and weedy. 

High Risk Traits:

• Broad climate suitability & thrives in tropical climates
  
• Elevation range exceeds 1000 m
  
• Widely naturalized
  
• Weed of agriculture and waste places
  
• Related Achyranthes species have become invasive
  
• Bracts and bracteoles are spine-tipped
  
• May have allelopathic properties
  
• Alternate host of tomato yellow leaf curl virus
  
• Tolerates many soil types
  
• Forms dense thickets
  
• Autogamous
  
• Can reach maturity in 1 year
  
• Seeds stick to clothes, fur, and feathers and easily transported by birds, mammals, and humans
  
• Forms a persistent seed bank
  
• Able to coppice
  

Low Risk Traits:

• Medicinal uses
  
• Requires full sun
  
• Does not spread vegetatively
  
• Herbicides provide effective control during the seedling stage