Dear Iain,
Thank you kindly for your most detailed and specific response. Your
remarks were most interesting and added to my knowledge base. I used to have
a stalled horse and I frequently added his manure to my compost pile. In
the United States, it is my belief that composted horse manure is used for
mushroom media. Spent mushroom media is one of the bulk materials available
for gardeners along with various soil mixes, bark and pumice. Overtime, I
have heard references to no horse manure and was curious about the reason.
Joyce Miller, Gresham, Oregon, USDA7