"
Thats quite worrying how would you know?"
Ask the supplier of the manure. I have yet to meet a farmer who HAS used it, so the odds are good that they have not, and thus just asking seems a reasonable approach to me.
I reckon the questions you would need would be along the lines of:
1) Have you sprayed aminopyralid on your pasture?
2) Have you had a contractor do any spraying (who might have used aminopyralid without telling you)?
3) Have you bought in any hay / fodder?
4) Does anyone else use your muck-heap?
The instructions on the packaging have been very clear for a year or two, maybe more, that the user has a very serious obligation to inform any potential user of the fact that aminopyralid has been used. (This obviously hasn't worked, otherwise there would be no current problem
![Sad :(](https://chat.allotment-garden.org/Smileys/green/sad.gif)
but it should mean that people do know or, when challenged, will put effort into checking with contract sprayers etc.)
The product is being considered for re-licensing (has been?) with much more draconian requirements for informing the user-chain. This may not amount to a bag-of-beans either, but I think it strengthens the case that the supplier should not be surprised if you ask the question; even if they know nothing about it (which I think would be pretty shocking within the farming community, but having said that most of the farmers around here are STILL not aware of the issue, so the farming press isn't doing a good enough job, or the farmers are just hanging their copies up in the outside privy ...) they ought to become acutely aware of the matter as soon as they research it.
If they don't know, for definite, that aminopyralid has not been used then I recommend that you "pass"
![Sad :(](https://chat.allotment-garden.org/Smileys/green/sad.gif)