Where Did That Yield Come From?
Faithful readers of this publication will notice that the title of this article is a repeat of an article from 2018. In this case, a long time GMS customer had entered a state yield contest for a particular seed company. The GMS customer did not win the contest; however, this customer was in the top three yields in the state competition. Since Growers Mineral, Corp. has started discussing our Cost and Availability Calculator for fertilizer, we felt a comparison with the competitors in this yield contest might be educational. To our surprise and to the surprise of the long term GMS customer, no one was interested in discussing applied fertilizer for the yield contest. Isn't that very interesting?
So, to do some cost and availability numbers for this article, we had to use numbers that the agricultural establishment has used when discussing the unit in and unit out approach to fertilization. For this discussion, we used the revised numbers promoted by Emerson Nofziger from the University of Illinois in the article "New Grain Phosphorus and Potassium Numbers" on the website www.cornandsoybeandigest.com from September 8, 2017.
The results of the yield contest was 299 bushels of corn per acre for first place while the GMS customer came in third with 287 bushels of corn per acre. So, with the help of the Cost and Availability Calculator, we would like to make some per acre cost and availability comparisons. Since the competitors in the contest aren't willing to discuss fertilizer usage, some assumptions will be used by following the agricultural establishment literature.
The GMS customer approach was very similar to the way many GMS customer grow corn. The customer strip tilled the field in the spring and applied 25 gallons per acre of UAN28 in the strip. While planting, 15 gallons of UAN28 was placed at a 2x2 position on both sides of thee row, and 5 gallons per acre of GMS was placed in-furrow with the seed. At pre-tassel, 20 gallons per acre of UAN28 was Y-Drop applied to the corn.
For the contest winning corn, the University of Illinois suggests using 0.37 pounds per acre of P₂Og and 0.24 pounds per acre of K₂O while applying 1 pound per acre of N for each bushel of corn production. In the state where the contest occurred, the majority of N is supplied with UAN28.The K₂O is supplied with bulk spread 0-0-60. The P₂O is supplied with 10-34-0 and a mono ammonia phosphate combination. So, 299 bushels of corn per acre would suggest 110 pounds of P₂Os, 72 pounds of K,O, and 299 pounds of N.
To reach those recommendations, a common approach is a 2x2 application of 10 gallons per acre of 10-34-0 combined with 10 gallons per acre of UAN28, 80 gallons per acre of UAN28 is side dressed, and 120 pounds of 0-0-60 and 140 pounds of MAP are bulk spread.
Since most farmers aren't trying to win yield contests, we used the Cost and Availability Calculator for a yield of 150 bushels per acre of corn following the protocols of the yield contest winner and the GMS customer. The results for the various approaches are presented in Table 1.
This is an excerpt from the Winter Growers Solution (2022) written by Jim Halbeisen, Director of Research.
Signup for our newsletter to stay in the loop
