ST. LOUIS — Monsanto Co. on June 21 announced it has completed its acquisition of Precision Planting, a Tremont, Ill.-based business aimed at helping growers maximize yields. The purchase, for $210 million plus up to $40 million in performance payments, was first announced in May. Established in 1993 by husband and wife Gregg and Cindy Sauder, the company develops and markets software, hardware and after-market production equipment used by growers as they plant and harvest as well as analyze field-by-field data to improve yields. Monsanto said Precision Planting has a product pipeline that includes a system designed at simplifying variable rate planting and increasing yields through more accurate planting. The business will remain in Tremont and will become a part of Monsanto’'s Integrated Farming Systems unit.