05/14/2026
๐๐ฆ๐ฉ๐จ๐ซ๐ญ๐๐ง๐ญ ๐๐ฉ๐๐๐ญ๐: ๐๐๐ฐ ๐๐๐๐ ๐๐จ๐ข๐ฅ ๐๐๐ง๐๐ฅ๐ข๐ง๐ ๐๐ฎ๐ข๐๐๐ฅ๐ข๐ง๐๐ฌ ๐๐จ๐ซ ๐๐ง๐ญ๐๐ซ๐ข๐จ
Recent research from the University of Guelph has prompted the Ontario Soil Management Committee (OSMC) to update soil-handling protocols for Pre-Sidedress Nitrate Testing (PSNT).
๐ป๐๐ ๐ฒ๐๐ ๐ช๐๐๐๐๐: ๐บ๐๐๐ ๐ญ๐๐๐๐๐๐๐ ๐บ๐๐๐๐๐๐.
While freezing was once common practice, peer-reviewed research (Janovicek et al., 2024) shows it can significantly skew results:
โ The Impact: Freezing and thawing increase measured nitrate concentrations.
โ The Risk: In over 50% of cases, frozen samples altered N recommendations. In 16% of cases, this led to under-application, causing economic losses exceeding $25/hectare.
โ The New Standard: Discontinue freezing. Instead, ๐ค๐๐๐ฉ ๐ฌ๐๐ฆ๐ฉ๐ฅ๐๐ฌ ๐๐จ๐จ๐ฅ and ship them to the lab as soon as possible after collection.
Accurate PSNT results are essential for balancing farm profitability with environmental stewardship. By switching to a "keep it cool" protocol, we ensure the data driving your in-season nitrogen decisions is as reliable as possible.
Read the full findings in the Soil Science Society of America Journal or contact OMAFA for updated agronomy guidelines.
NH4+ but not NO3โ test values were significantly affected by oven-drying relative to fresh extraction. Oven-drying altered pre-sidedress nitrate test (PSNT) nitrogen (N) rate recommendations in 34%โ...