Vast amounts of nitrogen (N) exist in our soils in many different forms, but only nitrate (NO3–) and ammonium (NH4+) can be taken up via the plant roots. Most of the nitrogen in the soil is in the organic form, which much be broken down by micro-organisms to become plant available. Mineralization is the process […]
Summary Pre Sidedress Nitrogen Test (PSNT) soil samples were collected from 94 sites across the province from June 8th to 10th, 2020 The average PSNT value was 14 ppm, slightly above the long-term average of 12 ppm. Optimal nitrogen (N) rates are a function of both soil N supply and yield. Consider both when determining […]
Co-authored with Ian McDonald Background OMAFRA Field Crop Unit staff have traditionally conducted an annual Pre Sidedress Nitrogen Test (PSNT) survey across Ontario at the beginning of June to measure background soil nitrate levels mineralized from the soil as an indication of year-to-year soil nitrogen status. In past years, 80-100 samples would be collected from […]
Co-Authored by Ian McDonald Background: In 2013 a range of corn fields were sampled to determine what impact the weather has had on the level of residual soil nitrate. This year April was cool and relatively wet while the first half of May came in warm and dry followed by conditions since mid-May that have been […]
Coordinated by: Ian McDonald and Greg Stewart, OMAFRA Background Annually the OMAFRA field crops team surveys a range of corn fields to determine what impact the weather has on the level of residual soil nitrate. In 2012 weather conditions have been almost polar opposite to last year when April was cool and May was wet. […]