The question of the importance of using the base cation saturation ratio concept (BCSR) in the nutrition of crops and for making soil test recommendations have been raised many times over the past 100+ years. Recently this issue has surfaced again as a part of programs promoted as “sustainable farming systems” or friendlier to the land or other parts of the environment. As others before them, the primary promoters of this concept are businesses promoting the use of calcitic limestone, or gypsum (CaSO4 ) to bring Wisconsin soil into better cationic “balance.”