Effective Microorganisms (EM) consists of a combination of three (3) groups of microorganisms: lactic acid bacteria, yeast, and photosynthetic bacteria. The lactic acid bacteria are the same ones found in sauerkraut, yogurt, cheese, sourdough; the yeast is the same one used by bakers, beer brewers, and wine makers; and the photosynthetic bacteria is the same one found in worm castings, in many soils and bodies of water. These microbes are found almost anywhere in the world and are not unique to any environment.