This UMN Extension article covers manganese (Mn) management for Minnesota crops, with soybean and corn as the relevant row crops (soybean is high-sensitivity, corn is low-sensitivity to Mn fertilization). Mn deficiency is more likely on heavily weathered sandy or organic soils with pH above 6.0 (mineral/calcareous soils above 6.5); toxicity can occur below pH 5.0. Deficiency causes interveinal chlorosis in young leaves (soybean: chlorotic between green veins, browning/death in severe cases; corn: interveinal chlorosis with stunting and white leaf flecks in severe cases). Diagnosis uses soil testing (DTPA method recommended; Mehlich-III not correlated with DTPA and not interchangeable) plus tissue testing (sufficiency ranges: soybean 17-100 ppm in most recently matured trifoliate leaves at early flowering; field corn 15-150 ppm in ear-leaf-base leaves at initial silk). However, DTPA soil test is not calibrated for Minnesota agronomic crops, so no soil fertilizer recommendations are provided for grain crops. Minnesota field trials (2011-2014, 18 soybean sites; 2011-2013, 8 corn sites) found Mn fertilization did not significantly increase tissue Mn or grain yield at any location for either crop, even where trifoliate Mn was above the sufficiency range. Bottom line: the University of Minnesota does not recommend Mn fertilization for any Minnesota field crop (only for sensitive vegetables on organic soils). If deficiency symptoms are suspected, confirm with both soil and tissue tests before treating, and report cases to the UMN nutrient management team. Note: foliar Mn can antagonize glyphosate efficacy in tank mixes; use chelated Mn-EDTA to reduce this interaction.