Fertilizing for 300 Bushel Corn

Gyles Randall of University of Minnesota made a presentation on Wednesday about fertilizing for 300 bushel corn and 100 bushel soybean's.  He was both entertaining and informative.  His first topic was - Can very high corn yields be produce with very low soil Phosphorous.  The short answer is no.  His data showed that with a 50 lb per acre P test, good yields could be produced no matter how much additional fertilizer was added or how.  Low P test was 20 bushels per acre lower even with more P added and no matter how it was placed.

This has an interesting implication for producers who are giving high cash rents.  We hear that many of those paying top dollar are "mining" the nnutrients in the soil by not applying Phosphorous and Potassium.  This data would lead me to believe they may be cutting their own throats in the long run. 

Dr Randall also discussed nitrogen management.  He is concerned that higher nitrogen rates needed to grow high yielding corn will also lead to higher nitrates in surface and ground water.  Right now, split applications show no advantage, but in the future we may need to look in that direction,  He also thinks that precision application with chlorophyll sensors hold promise.  I agree on that issue. 

Dr Randall also anticipates Sulfur, Zinc and Manganese issues.  Dr Randall has a longer article that looks very worthwhile in the Fluid Journal That was publicized today. 

My conclusion is that farmers and agriculture researchers are always striving to increase yield and profitability.  Both are challenges that I expect those of us involved in agriculture to meet.  Food, fiber, and energy demands lead us in that direction and currently the corn plant seems to be the best equipped genetically to meet the demand.