Corn Stalk Sampling Instructions
When to Sample: Take samples 1 - 3 weeks after black layers have formed on 80% of the kernels of most ears.
What to Sample: Cut stalk segments eight inches long. Take stalk segments from between 6 and 14 inches above the soil. Avoid damaged stalks and remove sheaths.
Amount of Sample: Within an area not larger than 10 acres, 15 stalk segments should be randomly collected. Together, these stalks form one 'composite' sample. Areas of differing soil types or management should be sampled separately.
Citation: Iowa State University Extension and Outreach, PM 1584, Cornstalk Testing to Evaluate Nitrogen Management A.M. Blackmer , A.P. Mallarino, 2000. Permission to use instructions and images was granted by ISU. For more information, visit: http://www.extension.iastate.edu/Publications/PM1584.pdf
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