Identification and Reproduction

Identification:

• Teasel is a biennial flowering plant that grows almost 2 m tall. 
• Will grow from a rosette its first and even in its second year. Rosette and basal leaves appear wrinkled and have scalloped edges. They are spiny on their underside. 
• Leaves on the flower stem are prickly along the middle of the underside. They are long and pointed with a distinct white midvein. 

• Flowering stems are ridged and prickly near the upper stem. 

• Flowerheads are eggshapped and flowers range from purple to white. They are surrounded by sparse, narrow prickly bracts that form around the seedheads. Flowers will bloom in rows. 

Reproduction: 

• Reproduction is solely by seed. 
• A single seedhead can produce 850 seeds, with each plant bearing 1 to 40 seedheads, resulting in as many as 34,000 seeds per plant. 
• Due to its unique flowerhead this plant is popular in floral arrangements.

Habitat & Ecology

• Teasel is often found in pastures, meadows, roadsides and other disturbed sites. 
• They thrive on exposed, sunny sites that occassionally experience wet soils. 
• Foliage will die after flowering and seedset. 

Impacts

Social:

• This plant is prickly and bitter to taste so is unpalatable to livestock. 
• It also takes up space, reducing livestock forage availability. 
• In cases that it forms dense colonies it can restrict recreational access. 

Ecological:

• Can overtake native grass species. 

Management

Mechanical/Manual Control: 

• Once flowering stalks are present sever the stem right below ground level. 
• Plants can also be removed by digging up the roots. 
• Repeat cuttings of the flowering stem will help eradicate populations. 
• Refrain from mowing the plants as root crown fragments can disperse and resprout. 
• Bag and dispose of mature seedheads to prevent regrowth. 
• Clean all equipment and clothing before leaving the infested site. 

Resources

For more information check out the King County datasheet on Common teasel identification and control. 

Header photo (Radio Tonreg).