Identification and Reproduction

Identification: 

• Iberian starthistle is a herbaceous plant that can grow up to 2 m tall. 
• Stems are very branched and sometimes referenced as "bushy". 

• Leaves are divided into narrow leaflets. 
• Rosettes have spines near the basal centre and form in May and June. 
• Flowerheads range from white, pink or purple. The bracts are straw-coloured and spiny. 

Reproduction: 

This weed produces seeds and are dispersed by wind, animals, humans, vehicles and by contaminated hay and crop seed. 

Habitat & Ecology

• Currently is not in Canada, but has been found in several states in America. 
• Typically grows in disturbed sites such as over-grazed rangelands and roadsides. 
• It is capable of growing in most soil types but prefers well-draining soils. 
• This plant is shade intolerant. 

Impacts

Social: 

• It is unpalatable to livestock. 
• Reduces the quality of hay and crops. 
• If it forms dense stands it can impede and injure livestock. 

Management

Prevention is a high priority for this plant. 

• Maintain healthy and diverse pastures. 
• Use clean, high-quality certified seed mixtures. 
• Make sure equipment, machinery and vehicles are free of soil and platn material prior to transportation. 
• Contact the Canadian Food Inspection Agency (CFIA) if you think you have seen this plant. 

Resources

Check out the Canadian Food Inspection Agency's datasheet on Iberian starthistle. 

For more for details check out the Invasive Species Compendium datasheet on Centaurea iberica. 

View header photo here.