Allen Parrish

Barrels and Pyramids When you see this barrel (displaying Liebig’s Law of the Minimum) or maybe even a pyramid showing what matters most, remember this about Liebig: • Liebig “conceded that chemistry alone could not increase yields. Agricultural science would depend as much on knowledge of plant physiology and soil structure as chemistry.” • “Liebig was careful to warn that… balance-sheet equations (for plants and soils) should not be taken in any absolute sense” • “Liebig very rarely referenced actual farming practice.” • On his book Agricultural Chemistry, Liebig said, “the book is not a guide to practical agriculture.” Fertility and/or yield are not as simple as following a math equation and hitting PPMs. Many use Liebig (mostly without knowing it) to defend ideas that Liebig himself would not defend. Remember this when you see these images in meetings in the months to come.