Identification & Biology
Alias' : Blue devil, viper's bugloss, blue-thistle, snake flower
Latin Name : Echium vulgare
Category : Terrestrial Plants
Description :
  • Biennial to short-lived perennial  
  • Bright blue blossoms 
  • Short, rough hairy stems that grow 30-80 cm in height at maturity 
  • Stem hairs have swollen dark bases that form noticeable flecks 
  • Leaves become progressively smaller as they approach the top of the plant 
  • Seeds (called nutlets) appear in groups of 4 along the stems. Individual seeds resemble the shape of a viper’s head.  


Blueweed reproduces up to 2800 seeds per plant that can remain viable for several years. Seeds are generally dropped in the immediate vicinity of the parent plant, but they can also be distributed by animals as the rough seeds stick to hair and feathers. Blueweed flowers in May through to September. The hairs on the stem of blueweed can be painful to touch. This plant develops a long black taproot sometimes over half a meter long. 

Blueweed is commonly confused with common bugloss (Anchusa officinalis)- a species with a similar coloured flower. While both plants are covered in stiff hairs, blueweed hairs have a swollen, coloured base which makes the stem appear spotted, unlike common bugloss. 

Look Alikes

Blueweed is a common invasive plant in central and south-central areas of British Columbia. Native to Eurasia, blueweed is well adapted to dry, rocky or shallow soils. Blueweed can survive in a variety of soil types and pH, but does not tolerate shade and requires well drained soils. Blueweed prefers warm, southern aspects. Blueweed can be found on roadsides, drainage ditches, right-of-ways, fence lines, pastures, rangeland, and other disturbed areas.  

Impact & Risks
  • Blueweed invades pastures and rangelands, replacing forage plants.  
  • Blueweed contains pyrrolizidine alkaloids, which can be toxic to livestock if ingested. Symptoms can include constipation or diarrhea, anorexia, lethargia, and a general loss of condition with the animal getting progressively weaker. More severe symptoms are changes in behavior, wandering, and liver failure.  
  • Blueweed can also cause skin irritation in humans, so gloves should be worn if handling this plant.  
  • Blueweed’s ability to compete with native plants in B.C. is unknown.  
Prevention & Mitigation

The most effective way to ensure that your lands do not become infested with blueweed is by prevention. Here are some recommendations to prevent blueweed from invading your property: 

  • Remove plant seeds from personal gear, equipment, vehicles and machinery at designated cleaning stations before leaving infested sites.  
  • Maintain your crops and natural lands in a healthy, vigorous condition to ensure a competitive plant community; competitive perennial grasses and forbs utilize water and nutrients that would otherwise be readily available to blueweed.
  • Regularly patrol your property for blueweed plants and immediately control or remove infestations before seed set. Do not leave plants to compost as they may still produce viable seed.  
  • Cooperate with adjacent landowners and encourage them to prevent blueweed spread. 
  • Immediately re-vegetate disturbed, bare soils with a suitable seed mixture that provides dense, early colonization to prevent weed invasion.  
  • Do not move contaminated soils to a new area.  
Treatment & Disposal
  • Hand-pulling may be an effective control for small infestations; cutting or mowing larger infestations will decrease seed production.  
  • Due to the ability to re-sprout, multiple treatments will likely be required to deplete root reserves to the point where flowering and seed production are unlikely.  
  • It is important to monitor treatment success over following years.  
  • Chemical control is also an option. Recent herbicide trials have shown that fall treatment is more effective than spring treatment. Before applying herbicides, read the label for full use and precautionary instructions.  
  • For further information on the selection and application of chemicals to protect your crop, contact AgriService BC at 1-888-221-7141 or email  
  • Currently, there is no biocontrol agent available for blueweed in BC.  
Okanagan Distribution

Priority Level Definitions

Watch For - Poses a significant threat (very high risk) and does NOT presently occur in the region OR is relatively new to the region and is very limited in extent.
High - High risk/impact; limited population with significant potential to spread in the region.
Medium - Medium risk/impact; limited distribution – broader population distribution with potential to spread further in a region.
Low - Low risk/impact; may be widespread or not, may be of concern in specific situations with certain high values – e.g. specific agriculture crops. Some species may be treated primarily with biological control agents.