Family: Asteraceae

An invasive forb that is native to Eurasia. There are several reports as to how dandelion came to North America. It could have arrived 10,000 years ago with humans as they crossed the Bering Land Bridge. Or it could have been introduced by the Vikings 1,000 years ago when they sailed to Newfoundland. Lastly, it could have been introduced by Pilgrims aboard the Mayflower or with the people who settled in Jamestown. There is evidence supporting each theory. Perhaps it was introduced by all three rather than a single accession.

The yellow flowers and the spherical seed heads are a common sight in yards on the mainland. This cosmopolitan species is found in every state and anywhere with temperate weather. It has a long history as a potherb and vegetable. Indeed, all parts of the plant are edible. Two hundred years ago, our pallets were much more attuned to bitter flavors. Today it’s much harder to enjoy the taste. As such, dandelions have substantially fallen out of favor. They are despised by people who enjoy a beautiful green lawn. While there are recognized medicinal qualities, it is not worth the risk of growing this in Hawai’i. Harvest it while visiting the mainland or, better yet, substitute dandelion for a native plant. 

Description and Dispersal:

• Rosette of deeply lobed leaves
  
• Hollow stem
  
• Exudes a milky white sap
  
• Brightly colored yellow flowers
  
• Seeds are 4 to 5 angled retain a long beak which is crowned with unequal, white, persistent bristles
  
• Has a large taproot
  
• Seeds are wind and water dispersed
  
• Seeds are spread unintentionally as a contaminate
  
• Plants are grown intentionally by humans
  

High Risk Traits:

• Elevation range exceeds 1000 m, demonstrating environmental versatility
  
• Broad climate suitability
  
• Naturalized in regions with subtropical climates
  
• Widely naturalized (including all main Hawaiian Islands except Kahoolawe)
  
• Primarily a weed of certain crops, gardens and amenity grasslands
  
• Other Taraxacum species are weedy
  
• Allelopathic
  
• Host of crop pathogens
  
• Shade-tolerant
  
• Tolerates many soil types
  
• Reproduces by seeds
  
• Hybridizes with other Taraxacum species
  
• Apomictic
  
• Can spread vegetatively by root fragments
  
• Seeds dispersed by wind, water, as a seed contaminant, internally in animals and intentionally by people
  
• Prolific seed production
  
• May form a persistent seed bank
  
• Tolerates mowing, cutting and grazing

Low Risk Traits:

• Unarmed (no spines, thorns or burrs)
  
• Palatable to animals and people
  
• Herbicides provide effective control