[Subversive_plot]

Sorry for the long post, the question is down at the bottom of you need to skip ahead.

I've read the Aminopyralid post under the FAQs heading, lots of good information there, but I am curious about one category of compost, and wondering if it might be safe?

Before I knew about Aminopyralid, last year I bought and used bagged compost, marketed as mushroom compost. I presume this is the compost used to raise mushrooms, once it's done for that purpose, it is sold for gardening. I was pretty happy with that product, and experienced no problems. The same brand (Black Cow) also sells a compost and cow manure product, it is widely used and respected over here. 

Reading up on aminopyralid, including some information from manufacturers (I know; caution), the effects of the herbicide are supposed to dissipate after a growing season.

Question: has anyone used similar mushroom compost and either experienced no aminopyralid problems (like me)? Or conversely, experienced problems? I'm hoping that even if the mushroom compost might have started with affected hay or manure, possibly the intervening use for mushrooms might have made it safer? If you have used mushroom compost, please let me know if you have had good, or bad, experiences. Thanks!

Added later: FWIW, aminopyralid is unfortunately still in use in the USA.

[snowdrops]

I haven’t any experience of using mushroom compost but I would advise you to sow some beans in some of it & also do some in ordinary potting compost as a comparison to be on the safe side, either beans or tomatoes show up the effects of the contamination very quickly apparently

[Subversive_plot]

Snowdrops, I might try that before using with this year's tomatoes, peppers, and eggplants. Thanks!

I still want to hear from mushroom compost users.  I'm just curious if anyone had any aminopyralid effects using mushroom compost (even if it's experience from a long time ago).

[jezza]

Hello Aminocoprodil herbicide is a lawn broadleaf weed killer supposedly a replacement for MCPA MCPP DICAMBA 24D,it was found to be in compost made from household garden waste it hadn't broken down as it should have done and was still active 9 to 12months later,the only way it can get into mushroom compost is if its been mixed with household garden waste compost,mushroom compost is very well rotted horse manure Amino coporodyl  isn't usually used where horses are I dont think it would do horses any good,that's why it's best to check the active ingredients on lawn weedkiller, it's still available in England   jezza

[Christine]

Jezza - we were told that Aminopyralid was sprayed on grazing land and went through the animals that ate the sprayed fields without breaking down on the way through their digestive system. Locally there was a problem with manure from horses years back and if it's a very elderly compost heap there still could be a problem. As for "supposed to dissipate after a season" - well the manufacturers would say that wouldn't they?

The best way to check is the good old broad bean test - if they grow the product is OK and if they don't you have problems.

[Subversive_plot]

Jezza and Christine:

Compost for mushrooms sometimes includes hay as well as manure. Here in the USA, aminopyralid is available for pasture and grass crops, but I'm not aware of any products where it is used for lawns. I think if aminopyralid got into the compost, it would be through the hay or manure.

I think I will do the bean test, see what happens.