Roots Organics Super Phos Bat Guano is incredibly high in phosphorus and calcium and is extracted from select caves when the quality is at its highest. Potent and powerful high phosphorus guano consciously extracted to not disturb the bat colonies, and to provide an unparalleled completely natural source of phosphorus and calcium. Roots organics super phos bat guano is fast acting and so powerful it should  be used carefully and sparingly. All of the roots organics guanos are carefully sourced for quality and harvested with bat friendly methods so you and your garden get performance with principles.