Corn yield response to plant population.

Maybe this is too late to be timely.  You already have your corn bought and maybe paid for.  As we move toward spring planting season though it may not be too late to look at plant populations needed to optimize yield.  The assumption would be that optimizing yield also optimizes profit.  Purdue University researchers have looked at optimum populations and found that optimum populations might be less than your seed company is telling you.   I can think of some reasons for that.  Researchers might not be using the latest varieties.  On the other side of it seed companies might not looking at long term results under less than ideal conditions.  While Purdue scientists say the optimum population is between 31000 and 33000, I have seen other researchers find that 34000 to 36000 plants per acre is optimum.  In all this I see no mention of variety.  We know that certain varieties optimize yield at certain populations.  There is also no mention of soil types.  We know that some soils will support higher populations and yields. Bottom line is that you need to combine your knowledge of your farms and your seed corn agronomist's knowledge of his product to determine what works best on your farm.  Don't overlook using well calibrated yield monitors to document difference in varieties on your farm.