Fleabane

This is NOT an edible weed although it has been used historically for various medical problems.


Binomial name : Conyza canadensis or Conyza bonariensis

Common name : tall fleabane, flaxleaf fleabane, asthmaweed

Conyza is derived from the Greek word Konops meaning flea and bonariensis from Buenos Aires in Argentina where this plant may have originated from. The canadensis is self explanatory.
The common name fleabane is named thus as the ground seeds of the plant are supposed to have a flea repellant effect, although Culpepper (1653)wrote that it obtained it's name because the seeds looked like fleas.
When I discovered the name for this weed recently I just had to research it -the common name is intriguing. It is very common on my property and now I know why - seed production per plant is upwards of 120,000! As the name indicates it comes from the Americas but is now cosmopolitan.


Identification:

Fleabane is an annual weed with a single stem to about 1-2m - C bonariensis has lateral branches from near the top of the main stem that overtake it whereas C canadensis tends to be unbranched. There are also differences in hairs on bracts ( bracts are the scale like leaves at the base of a flower) I am reasonably certain that I have the latter variety - I tend to pull it out before it gets too tall and thus have not closely examined the stalk. The lower leaves droop and look half dead, the other leaves have a slightly hairy feel and look.



Uses :

Historically it was used in the treatment of diarrhoea and haemorrhage and applied externally for skin infections

Pubmed search:

search term Conyza bonariensis :
abstract 5 : essential oils from CB showed an inhibition of the inflammatory reaction and nitric oxide production in a mouse model abstract 7 :3 glycosides from CB had a weak inhibitory effect on xanthine oxidase
My comment on this is that chickweed seems better for this latter effect.

search term fleabane
abstract 10: Erigeron (old name) annuus extracts had some potent inhibition of some diabetic metabolic products and pathways. The idea being that these result in the diabetic complications seen regularly clinically and if they can be blocked it may help prevent such occurring.

search term Conyza:
abstract 19: C canadensis extract showed strong inhibition of platelet aggregation.

Now this runs contrary to the traditional use of stopping haemorrhage or bleeding!

Conclusion :

Not a weed I will be using until there is better reason to do so. Some interesting early findings on the seach for novel compounds to help treat diabetic complications.