ID this cosmopolitan weed? Spanish needles (Bidens pilosa)

What is this plant? I think it's a cosmopolitan weed. A few Ladakhis here grow and use it for tea, but a rumor has gone round that it's harmful, causes kidney stones or something, so it's fallen out of favor. I saw it growing as a common weed in Himachal Pradesh India, and a foreign friend there told me it's a pesty weed in South America but he didn't know the name in English.

Just for your entertainment, I'll tell you that Ladakhis use it not for normal sweet tea, but for salted butter tea, and they think it tastes enough like the real thing that some believe it actually is the same plant as when you buy tea in the market.

Here are more pictures. I'm afraid you'll think I'm an idiot, since I have a feeling this will turn out to be a really common weed that I should have known.

Rebecca Norman wrote:What is this plant? I think it's a cosmopolitan weed. A few Ladakhis here grow and use it for tea, but a rumor has gone round that it's harmful, causes kidney stones or something, so it's fallen out of favor. I saw it growing as a common weed in Himachal Pradesh India, and a foreign friend there told me it's a pesty weed in South America but he didn't know the name in English.

Just for your entertainment, I'll tell you that Ladakhis use it not for normal sweet tea, but for salted butter tea, and they think it tastes enough like the real thing that some believe it actually is the same plant as when you buy tea in the market.

Not 100% certain, but that looks like Spanish needles (Bidens pilosa). If so, I don't know its value as a tea, but I can tell you that it is a real pain in the "whatever it comes into contact with" when it forms its seeds (aka needles).

Thank you, that's it!

I've googled it up, and the first page of results seems to have both herbalist websites and weed ID websites. I haven't read them yet, though.

Rebecca Norman wrote:Thank you, that's it!

I've googled it up, and the first page of results seems to have both herbalist websites and weed ID websites. I haven't read them yet, though.

Glad I could help. Please let me know what you find out about any potential usefulness for this plant. In our area it comes in as a weed (usually from hay) and spreads waaaaay too quickly. If you or your animals walk through it when it's in seed, those little needles grab hold and are a real pain -- both while they're sticking in you, and when trying to pull them out of clothing and hair. I hate the stuff and usually spend more time than I can spare trying to root it out and eradicate it wherever I can. It can take over an area really fast, so it would be nice if it at least had some benefit.

The uses mentioned on various medicinal herb websites are too varied so my eyes kind of glazed over, sorry. The one thing that several agreed on was that the young leaves and shoots are eaten as a vegetable in Africa.

You might find this interesting about Bidens pilosa from AVRDC The World Vegetable Center:

http://avrdc.org/category/main-iv/
then,
http://avrdc.org/blackjack-bidens-pilosa/

"Blackjack (Bidens pilosa)

Often gathered while growing wild, blackjack can be cultivated as well.

Common Names
Blackjack, Spanish needles (En); sornet, bident hérissé, herbe aiguille (Fr); bidente piloso, mozote, margarita silvestre (Sp); 咸豐草 (Cn)

Plant Distribution
All tropical and subtropical areas

Edible Parts
Tender shoots are eaten boiled or stir-fried, or powdered and added to sauce.

Health Values
Beta-carotene: high; vitamin E: medium; ascorbic acid: high; calcium: low; iron: low; protein: 3.0%. Leaves contain also anti-inflammatory, antioxidant and antigastrointestinal
bacterial coumarins, flavonols and stilbenoids (flavonoids), phytosterols, polyacetylenes, and triterpenes, as well as saponins."

We know it as cobblers pegs in Australia and the seeds stick to everything (especially socks), spreading easily. It is a pioneer species that tends to take over dry, bare ground - I have a big patch growing in a neglected area. Rather than pull it out (which I am very tempted to do) I am waiting to see what grows through it next via succession. As for control, I have observed chickens eating it - but only when all the other juicy tasty weeds are gone.