Of all the micronutrients, iron is taken in by soybeans in the highest quantity. For example, 60-70 bushel soybeans pull in nearly two pounds of iron! Beans want that to be in the ferrous form (2+ charge), so if your soil pH is above 7 and especially above 7.4, you may need to supplement iron in the ortho-ortho chelate form to ensure plenty is of the ferrous form is available. Iron is super important, as it’s required for the formation of chlorophyll. Iron is also involved in respiration, nitrogen fixation, and energy transfer, among other things.