SpecialK, Etal,
I wouldn't be surprised! Most store bought mushrooms are raised in a mixture of animal manure. Probably should wash anything growing in cow manure thourghly before eating, otherwise it'll taste like the host nurturant.
People seek "range fed" chickens, turkeys and beef because it's healthier than feed lot food. Any idea what chickens and turkeys eat on the open range?
Organic farmers use animal manure to fertilizer their crops rather than chemicals! Most people think those vegetables taste better than produce raised on artificially made chemical fertilizers. Germans use 100% of their pig farm manure to fertilize their crops.
The mushrooms growing directly in cow manure will either kill you or make you see funny lights! Interesting choice on your part!