In episode 9 of Corn College TV, Farm Journal Associate Field Agronomist Missy Bauer answers one farmer’s question on how to go about doing corn stalk nitrate tests.
“The test should be done one to three weeks after the black layer has formed,” she advises.
Here’s the step-by-step procedure:
· From the ground, measure 14” up the stalk.
· The sample should be 8”, so cut at the 14” mark and then again at the 6” mark.
· Repeat to get 15 stalk samples.
· Randomly pull through the sampling area, respecting soil types.
· And then send into the lab.
- Bauer explains that the results will come from the lab in parts per million of nitrate in the stalk. Here are guidelines for interpreting the results.
· Nitrate concentrations:
· Low = less than 250 ppm
· Marginal = 250 to 700 ppm
· Optimal = 700 to 2000 ppm
· Excessive = greater than 2000 ppm
To learn more about stalk nitrate sampling watch episode 9 of Corn College TV.


