Better get it from local stables if you can,especially if they can assure you no herbicides were used on the fields. Much cheaper too!(though you have to compost (and sometimes shovel it) it yourself of course...)

You should certainly get in touch with the suppliers. Aminopyralid weed killers are under strict usage controls and if it is getting into animal manure then they are not following the laid down guidelines.
They should compensate you for the damage their material has caused.

http://www.puyallup.wsu.edu/soilmgmt/Pubs/CloBioassay.pdf.........
Have a read of the above article I found and it confirms what I suspected what I got wrong was I thought the manufacturer was putting herbicide in the compost but it's the material they are collecting that has the herbicide in it.

...which is why its best to get it direct from the stables if you can as they should be able to tell you what if anything has been used on the feed. Ours does anyway.

Can I just ask, did you use the product in your potted plants, or on open ground?

This is the hazard of using fresh manure. It should be blended in really good.

It wasn't fresh though, it was ready composted.

So then the herbicide in question is not from this bag of compost. It's from another source.

For Bathgate. The aminopyralid type herbicide remains active even after passing through an animals digestive system. So if the manure was collected from a source where this kind of herbicide has been used, it would contaminate the end produce even if it was sterilised before sale.

For Owdboggy: Manure is composted for this very reason. Inherent chemicals, herbicides, pathogens are properly broken down and rendered ineffective (takes at least 6 months). This is not the same as "Sterilization".

As per Steragram's comment, the herbicide must have come from elsewhere, not this bag of compost. Just read the bag for yourself "Composted Stable Manure". That's what they are saying.

Sorry, but for once the composting of stable manure does not break down this herbicide. It remains active even after commercial extremely hot composting. There have been a large number of problems caused by this stuff, to the extent that companies have been forced to remove soil from allotments to get rid of the contamination.

I'm simply describing the standard composting procedure & why it's necessary to compost manure. I can't think of any herbicide that can be ingested by an animal, pooped out, and still remain active. Garden compost with built in herbicide makes no sense whatsoever - but then we are talking about the UK. There must be more to your story. No? And this...

'In fact, the majority of residentially sold weed killers are required by law to break down in the soil within 14 days, if not sooner. Take Roundup, for example, which contains glyphosate. This post-emergent, nonselective herbicide generally breaks down within days to weeks depending on the Roundup product you have.'

https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/how-long-does-weed-killer-last-in-the-soil.htm

https://www.rhs.org.uk/advice/profile?PID=477
Explains it better than I can .

Sorry I'm late and I would just like to add a couple of things ...I am certain that this is due to herbicides due to other photos I've seen that look exactly distorted the way some of my plants. This is hay or straw that come from farms that use herbicide and seeing as this compost is at least 90% hay or similar then it stands to reason that some of my plants have suffered mainly when the roots are directly in contact with the material this I repeat has not only been used as a top mulch but to also plant directly into. And it is folly to think this is actually stable manure or has been anywhere near an animal considering the 100s of thousands of bags of this stuff that is sold every year . I have come to this conclusion after reading articles on the net mostly from america

All I'm saying is that herbicides become inert rather quickly. It's just natural decomposition of a complex man-made chemical. How would that company expect to survive - selling used herbicide as compost? That's what's hard to believe.

This product is not intended to be used for directly planting into of any sort, either in the ground and especially not in pots. It should never be added to pots even as a mulch on top. Its intended usage is to be dug or spread onto the soil (usually empty soil, but not necessarily) because it is a composted soil conditioner, not a potting compost.

The reason it is only intended for use on open soil is because it may contain pathogens which will severely affect plants in pots, or if you plant something directly into it. Distributed across open ground, any pathogens present are extremely unlikely to cause any problems.

If you did not use the product correctly, I'm not surprised you've got trouble.... there was a major problem with some of these products starting some ten years ago, to do with aminopyralid, but a bagged product like this bought recently should not have this problem now, in the UK, regardless of what the American websites say.

Some of the misuse of 'composts' is because we in the UK use that term to mean various things and it can be confusing; we have potting compost, seed and cutting compost, garden compost, animal manure compost and so on, but only those with the word 'potting' somewhere in the description should be used to plant into. Those with the words 'soil conditioner' should not be placed directly around the roots of plants unless well mixed with garden soil, and never used in pots.

https://www.google.co.uk/url?sa=t&source=web&rct=j&url=http://smallfarms.oregonstate.edu/sfn/f09Herbicide&ved=2ahUKEwjP-LKD4P7cAhVPZlAKHdRCDGAQFjACegQICxAO&usg=AOvVaw1PSnZpCAXFuQYEof5gPCbB this shows a picture of herbicide damage and it's exactly the same as my plants pity you can't open this