Family: Asteraceae

Carthamus tinctorius, widely known as safflower or “Dyer’s saffron,” is a thistle-like annual herb with a long history of cultivation throughout the Middle East, Africa, and Asia. This sturdy plant features stiff, upright stems and prickly, globular flower heads that bloom in brilliant shades of yellow, orange, and red. For centuries, it was prized for the potent dyes extracted from its colorful florets, which were used to tint textiles and food. In modern times, it is most recognized as a versatile commercial crop; its seeds are a major source of vegetable oil, and the plant is frequently used in birdseed blends and as a drought-tolerant ornamental in sunny gardens.

Despite its many uses, safflower is considered a high-risk species because of its ability to naturalize and persist in the wild. It matures quickly, completing its life cycle in less than a year, and the most common varieties are heavily armed with sharp spines that can make movement through infested areas difficult for people and livestock. Safflower is already managed as a weed in several regions, including Australia, where it competes for resources in disturbed soils and agricultural lands. Its ability to hybridize with other thistle species and its tendency to be spread accidentally through contaminated seed or machinery further contribute to its invasive potential. However, because it is shade-intolerant, it typically poses a greater threat to open fields and roadsides than to healthy, shaded forest ecosystems.

High Risk Traits:

• Widely naturalized
  
• Controlled as a weed in Australia
  
• Spiny form most common
  
• Hybridizes with other Carthamus species
  
• Reached maturity in <1 year (annual life cycle)
  
• Seeds may be accidentally dispersed

Low Risk Traits:

• Documented as a weed, but impacts minor or unspecified
  
• Palatable to grazing animals
  
• Non-spiny form exists
  
• Source of food and dye for humans
  
• Shade-intolerant
  
• Herbicides would likely provide effective control