Using the Pre-Sidedressing Soil Nitrate (PSNT) ‘Quick Test’ to Guide N Fertilizer Management in Sweet Corn (2013)
The following is a method for cheaply and quickly determining a soil’s nitrate status for the purpose of determining the midseason sidedress fertilizer rate for sweet corn. For information on the pre-sidedress nitrate test (PSNT), see OSU’s nutrient management guide EM 9010-E (Sweet Corn- Western Oregon). The ‘Quick Test’ (QT) has been in use for years in the Salinas Valley of California with good results. Compared to a traditional laboratory test, it is cheaper and test results can be obtained within hours of sample collection. Although this method is semi-quantitative, results from the QT are well correlated with laboratory results.