By John Ippolito PAg, Crops Extension Specialist, Kindersley
The 4R Nutrient Stewardship Initiative is a program developed to encourage the best management practices for the use of fertilizers. The basis of the concept is applying the right source of nutrient, at the right rate, at the right time, and in the right place.
These practices are being demonstrated through the Agriculture Demonstration of Practices and Technologies (ADOPT) program, which is supported by both provincial and federal governments through the Canadian Agricultural Partnership (CAP), and Fertilizer Canada.
AgriARM sites at Indian Head (IHARF) and Melfort (NARF) demonstrated fertilizer placement practices and sources in trials that were conducted on wheat in 2017. Placement methods included side banded at time of seeding, pre-seeding surface applications, and split applications with 50 per cent of the fertilizer side banded followed by surface applications about four weeks later.
Sources of fertilizers included urea, urea ammonium nitrate (UAN), Agrotain, and Super U. Rates of .5 X, 1 X and 1.5 X recommended rates were used for side-banded urea. All the other treatments were done at the 1 X rate. The 1 X rate was the combination of soil nitrate nitrogen and applied nitrogen being 130 kg per hectare.
At Melfort, yield and protein levels in the control, 0.5 X side banded urea and pre-seed dribble band UAN applications were similar indicating that there were losses associated with the dribble band application. All other combinations that applied the 1 X rate or higher were sufficient to increase yields and protein, but they were not significantly different. Protein content was reasonably low across the treatments, which would indicate that nitrogen application rates could have been higher at this location.
In the IHARF trials, there was no significant difference in yield between the fertilizer treatments. The side-banded urea treatment provided a significant increase in protein content compared to the other treatments.
Both locations experienced a drier-than-normal growing season but started the season with good stored soil moisture. The expectation would have been to experience some protein increases from split applications but that was not the case. The lack of precipitation during the growing season may at least partially explain this result.
The conclusion of these trials supports that side-band application of the recommended rates of nitrogen is the appropriate practice in these growing conditions.
For full details on these demonstration projects, contact the Crops Extension Specialist in the Ministry of Agriculture Regional office closest to you.