Please note if you plan to start from a spore solution you need to begin with magic Mountain Grain Spawn.Manure Based Mushroom Substrate is specially formulated mushroom growing substrate for growing gourmet edible mushrooms. We take 10 year + aged horse manure and fortify it with all the necessary minerals and vitamins that mushrooms need to grow. Manure Based Mushroom Substrate can be used in addition to our mushroom sterilized grain spawn and mushroom casing. You can mix and match our products to make your own personalized mushroom grow kit. We get our manure form one single source. There horses are organically fed and very healthy. Our supplier has aged manure up 14 years old. There is no doubt this is the best mushroom growing substrate you can get on the market today. Myco bags are very convenient and this how many professional mushroom growers choose to grow there mushrooms. The moister content is guaranteed in the sterilized mushroom substrate. We have a huge autoclave that we use to sterilize our substrate. This makes sure there is no bacteria or mold spores left living in the compost. You will receive a myco bag full of enriched mushroom substrate that any dung loving mushroom species will thrive on. I have personally seen up to 6 flushes of mushroom from 5 pounds of Out Grows Manure Based Mushroom Substrate. That"s because there is so much nutrients available to the mushrooms they just keep on fruiting.We package our Manure Based Mushroom Substrate in pre sealed 10" myco bags with built in pre-filter. These are currently the best myco bags available for home mushroom cultivation. This will insure that you receive the freshest substrate possible. This is perfect substrate for all gourmet dung loving mushrooms.