Not useful but, sort of on topic?
We get trailer loads to spread on the fields... It makes the BIGGEST bird feeder ever once it's fields are covered with every goose, all the little finches and birds, and then you can watch all the Hawks and predatory birds coming in - more exciting than to by far!
Also, one evening, went out for walk and my dog drank from a puddle at bottom of the heap - I shouted him off it, but few minutes later he was staggering all over the place! (I was panicked, but, chat to the vet and he was fine the next day.)