This University of Minnesota Extension guideline on soybean fertility (reviewed 2026) addresses several micronutrients. Manure and multi-element fertilizers used in rotation supply micronutrients but the article's micronutrient-specific guidance covers boron (B), manganese (Mn), iron (Fe), and briefly zinc/copper/magnesium. Boron: soybean has low tolerance to B, with toxicity possible at broadcast rates as low as 2 lb B/acre; UMN research has not shown a yield benefit from B application, and excess B is more likely to reduce yield than help it, so B application is not recommended. Manganese: soybean has responded to Mn in other U.S. regions with historically Mn-deficient soils, but Minnesota research has not shown a widespread need; recent data suggest a possible response when soil pH >7.4 and DTPA soil Mn (0-6") is ≤10 ppm, in which case 10 lb broadcast Mn/acre may be warranted; foliar Mn has not been tested and should only be tried on a trial basis. Other micronutrients: Minnesota trials show no yield response to magnesium, zinc, or copper application in soybean, so these are not recommended. Iron deficiency chlorosis (IDC) is highlighted as the main micronutrient-related production issue: occurs on fields with pH ≥7.4 due to impaired Fe uptake (not true soil Fe shortage); best managed via tolerant variety selection (using UMN chlorosis-score trial data), minimizing plant stress (herbicide injury, salts, compaction, deep cultivation, seedling disease, carryover nitrate), in-furrow EDDHA-Fe chelate (ortho-ortho form) at 1-3 lb active ingredient/acre at planting, and/or an oat companion crop (1.5 bu/acre, killed at 10" height) to reduce IDC severity in badly affected areas. Growers in IDC-prone fields are advised to combine a tolerant variety with EDDHA-Fe and/or the oat companion crop.