Published October 12, 2020 | By Mike Petersen
Our first of several results to you is on paper and ready to re-report. Just recently (10-5 to 10-9) we with AKRS Equipment providing us a S770 combine (leased) harvested the Vo-Ag study of placing pre-plant nutrients with two offsets to provide growers an up close and personal look at what corn does and the importance of being right on the money with fertility placement and where the seed sits above the nutrient package. So two weeks prior to planting back in April we strip tilled in a package of N-P-K & S at a depth of 6.5 inches. then Pat bumped the GPS to offset by 4 inches and then 8 inches where the plant would grow and develop it’s root system. We did 48 rows of each approach of a Dekalb 110 RMD variety.
In the corrected table to your left; the O inches details that we planted the seed directly above the nutrients we placed with the Orthman 1tRIPr in early April; the 4 inches offset tells us what it is when we miss the mark and seed is four inches to the right or the left of the nutrients and what kind of results are. Then the 8 inch offset is when seed is 8 inches off from being directly over the top of the nutrition below by 6.5 inches. I had to correct the table because I had the offset plot data sets west to east with the 8 inch offset numbers as the O inch offset, as well a planting blank spot which needed to be accounted for, and then I had not corrected for the moisture percentage, oh my faux paux!! I apologize.
What do you see in these numbers? Yield is down by 5 bu/acre in the 4 inches and 8 bushel/acre down from where the seed and nutrition line up perfectly. Okay that is fine and dandy. What can a person have as a Take Away from this field study? Accuracy pays for itself first off. A $3.60/bu corn that is an improvement of $28.80/acre when 8 inches off. If a grower is not using GPS guidance by now and wandering around the row and where you placed a band of nutrition, RTK guidance can and will be a good investment, for the long run. Placing nutrition is valuable by offering you accuracy and food for the plant to run into since a corn root system does not go hunting for that expensive fertilizer, it has to run into it. A good RTK system is around $25,000 give or take. In order to pay for a system connected and ready to roll when you go to the field in one year it would take 5 – 128 acre pivot fields of corn to make it work the first year. Or 3 pivots over a two year period. Corn prices step up, it could be fewer acres. Take the wear and tear off the planter driver, how this can translate to your other tools you pull through the field and this takes fewer acres even more. This year the plots we had were 48 rows wide by 650 to 679 feet in length due to the shape of the field. Next year (2021) will be soybeans and a different set of studies.
All season long we watched the corn in the three plots exhibit growth differences, population and time to get to Black Layer. The 4 inch and 8 inch offset was always further behind where we planted right over the top of the placed nutrients. The young people under the lead of Mr. Tom Hofmann at the Polk High School watched and measured what was going on and came out to be part of the harvest since they get a portion of the proceeds to fund many of their Vo-Ag/FFA projects in the classroom and shop. The relationship Orthman Manufacturing has with these young folks in the FFA program is super and we thoroughly enjoy working with them all growing season and teaching agronomic and economic principles.