This organic farm is 107 acres cultivated and 133 acres pasture. I raise alfalfa, corn, wheat and some soybeans. I have a small cow calf operation with my brother. The organic cropland is tilled and cultivated. We graze the stalks in the fall with non organic cattle. We use a cover crop in the off season.
I have carried out sustainable practices prior to receiving this grant. I started farming in 2006, raising alfalfa on this farm for 3 seasons, then rotating to corn. I continue to use wheat as a cover crop to help control insects and weeds.
This project is designed to see if the use of 25 tons per acre of cattle manure on a 74 acre pivot farm in Hitchcock County Nebraska is more or less profitable than not manuring the soils in organic crop production.
With nitrogen being limited in organic crop production, we had Kelly Doetker with Double D spread 25 tons cattle feedlot manure in strips on our organic popcorn field, in late November 2010. One hundred pounds wheat seed per acre had been drilled in 15 foot strips as a cover crop in October of 2010 and was about 2 inches tall at the time of manure application. Nitrogen from the manure should increase corn yields, but will the wheat as a cover crop use up too much nitrogen prior to when the corn crop has nitrogen needs? Fall 2010 soil tests showed 16 pounds nitrogen in the 0-8 inch soil depth and 23 pounds nitrogen in the 8-36 inch soil depth. Manure tests showed 16 pound organic nitrogen per ton and 0.26 to 3.91 pounds ammonia per ton. Manure was not incorporated, but 0.4 inches of rain was received with 1 week of manure application. Field was disced May 6th and planted at 34,000 population May 8th….with 25,000 seedling stand. June 2nd field was cultivated. June 4th field was rotary hoed. June 11 field was rotary hoed 2nd time. June 15 cultivated 2nd time. June 23rd field was rouged. June 25th field was hilled. Normal rain fall and irrigation applications were made throughout the growing season. Fall 2011 soil tests after harvest showed 22 pounds nitrogen in the 0-8 inch depth and 18 pounds nitrogen in the 8-36 inch soil depth.
I utilized Darwin Hinrichs, our local Extension Service and NRCS person in the Trenton office, 308-334-5292. He helped monitor the progress of the wheat cover crop and evaluated the weed pressure in the field where the manure plot was located.
My primary assistance came from Charles Shapiro and his staff at the University of Nebraska-Lincoln (UNL).
David Glett, Graduate Student
Agronomy & Horticulture
UNL Haskell Ag Lab
57905 866 Road
Concord, NE 68728-2828
or during academic year:
361 Keim Hall
Lincoln, NE 68583-0915
David Glett help set up the plot design and spent several days throughout the 2011 growing season monitoring the plot and collecting data.
I am an agronomist and monitored the crop throughout the growing season as well, and took yield data at the end of the season, using our combine and an Ag Venture weigh wagon. Kenny, the Ag Venture representative for our area, weighed the plot strips, and collected test weight and grain moisture data.
This field has been farmed transition organic and organic since I purchased the farm in 2006.
June 11 weed evaluations were made. In a 4 inch wide band across the root and 1 foot of row length, there was an estimated 20-40 foxtail grass plants, 0-1 lambsquarter and 0-3 waterhemp on both the manured and non manured strips, and in both the wheat cover crop and non cover crop strips, which had been tilled prior to planting. Thus no noticeable differences in weed pressures were present in the manured and non manured strips. (See attached pictures.) There was, however, some kochia present in the manured strips from the manure, which was removed with discing prior to planting corn.
Yields results are on attached paper work. Plot yields were harvested with our combine and weighed individually with a weigh wagon. Manured strips with No Cover Crop yielded 115.73 bu per acre. Manured strips with wheat Cover Crop yielded 103.93 bu per acre. Non Manured strips with No Cover Crop yielded 121.99 bu per acre. Non Manured strips with wheat Cover Crop yielded 92.51 bu per acre. The overall average on the Manured strips was 108.03 bu per acre, as compared to the overall average of the Non Manured strips at 100.23 bu per acre. Therefore, overall the Manured strips out yielded the Non Manured strips by 7.8 bu per acre. Crop was marketed at an average price of $11.31 per bu, or $88.22 more income per acre on the manured strips. Manure cost with application was $141 per acre.
I learned that Manure application in an organic system can be profitable. One challenge is the cost of transportation for the manure from the feedlot to our organic farm. Nitrogen remains one of our more limiting factors in organic production however, if utilized along with an alfalfa rotation, I think organic farming can still be profitable. With the proper nutrients we can attain good yields. One disadvantage to organic production is weed competition. Manure application didn’t appear to increase the weed pressures in the growing crop. With a 7.8 bushel per acre overall average yield advantage with manure, manuring an organic corn crop may be profitable, depending on the cost of manure with trucking.
Results of this manure study have been published on the UNL On Farm Website, have been given to Ron Seymour Adams County Extension, and to Darwin Hinrichs NRCS in Hitchcock County, where the trial was carried out. These results are available through these two offices as well.