How Pictsweet mushrooms grow

How Pictsweet mushrooms grow: "The mushrooms you buy in the store today began their life in a laboratory about 3 or 4 months ago. No seeds or cuttings are planted. Mushrooms are grown from microscopic spores. Under sterile lab conditions, billions of microscopic spores were collected as they were released from the gills of a mature mushroom. The laboratory conditions are controlled so that no contamination takes place. Cereal grains - rye, wheat, millet and other small grains - are soaked in water and chalk and sterilized. Then they are injected with the mushroom spores. Soon, the spores send out tiny, white threads called mycelium. These mycelia are the 'roots' of a mushroom that collect water and nutrients to enable mushrooms to grow. The grains are incubated to promote full colonization of the mycelia, at which point the mycelia-laced grains are known as spawn. These spawn will be the 'seeds' the mushroom farmer will plant."