The pre-sidedress nitrate test (PSNT): Sampling, standards & values to know

About this episode

The episode discusses the pre-sidedress nitrate test (PSNT) and its implications for nitrogen management in crops.

Brad and Jeff continue their discussion about variable rate nitrogen technology by zeroing in on the pre-sidedress nitrate test (PSNT). What are key differences between the PSNT and the pre- plant nitrate test (PPNT)? What growth stage should the crop reach before taking a PSNT? How have sampling and storage procedures evolved from past years? How variable can samples actually be within the same zone and between zones? What should farmers watch out for when interpreting test results? Do different methods of N application produce different PSNT results? How about timing? Manure? What's N's 'critical value' in Minnesota? All these answers and more in-depth discussion on today's episode of the Advancing Nitrogen Smart Podcast. Guests: Brad Carlson, Extension educator (Mankato) Jeff Vetsch, Lead researcher, Southern Research and Outreach Center (Waseca) Additional resources: What’s the right PSNT number? New research refines the critical threshold for corn nitrogen decisions in Minnesota Video: 6 takeaways on the pre-sidedress nitrate test Tips for Accurate Pre-Sidedress Nitrate Tests Split-applying nitrogen for corn: Three keys for successful sidedress applications Understanding…

People in this episode

Guests: Brad Carlson, Jeff Vetsch

Topics covered

• pre-sidedress nitrate test
• nitrogen technology
• crop management
• sampling procedures
• test interpretation

Keywords

• PSNT
• nitrogen application
• crop growth stage
• sampling
• test results
• critical value

Mentioned in this episode

Organizations: University of Minnesota Extension, Southern Research and Outreach Center

Places: Minnesota

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