We have a patch of ground that was previously devastated by our chickens.
They are fenced out now and it is recovering nicely.
Since February I've been sowing the space with clover.
I used clear totes as cold frames and it really seemed to work.
I've added winter rye, buckwheat and hairy vetch to as I've expanded.
Amidst the clover patch some "weeds" have shown up.
I recognize some of them like lambs quarters, but this one is unknown to me:
Some sort of Brassicaceae species. The Brassicaceae includes: Radish(Raphanus raphanistrum), Winter Cress (Barbarea vulgaris), Turkish rocket(Bunias orientalis), White mustard(Sinapis alba), Pepper Cress(Lepidium sativum), Honesty(Lunaria annua), Dame's rocket(Hesperis matronalis), Wild Rocket(Diplotaxis tenuifolia), Wasabi Arugula(Diplotaxis erucoides), Arugula(Eruca vesicaria), Suneson Camelina(Camelina sativa), Garlic mustard(Alliaria petiolata) - many others. There are also of course - the Brassica species as well.
None of what I listed seems to resemble what you have exactly.
I am having a hard time thinking of any Brassicaceae species that include toxic plants - some of the types that I mentioned are best eaten in small quantities, possibly oxalic acid issues - nothing that will kill you though. Whatever you have should be safe for the chickens to eat. Suppose you could try saving seed considering it is already flowering - see what younger plants look like, could be a rare species as well. Could work in a permaculture setting considering it is probably edible and reseeds itself.
Good luck on finding the exact genus / species though.
Thank you very much!
After reading up on it, I will probably give it to the chooks.
I have a nice easy to eat strain of mustard green established in my yard, I would hate to displace or crossbreed with that.