Corn Stalk Nitrate Test (CSNT)

Corn Stalk Nitrate Test (CSNT) is performed by farmers to evaluate the N levels within corn just before harvest time or immediately afterwards. The CSNT provides an analysis of N management practices, and whether they were adequate or excessive during the growing season. These results give an evaluation of N management practices for a specific field. Running CSNT will require multiple years of testing to accumulate an accurate representation of N practices.

A CSNT should be performed either a week before corn harvest or within four days immediately following harvest time. It is recommended that CSNT be performed on 2^nd or higher year corn. The CSNT can help gauge effectiveness of new N protection programs or the application of N on fields.

CSNT Sampling Guidelines

1. Sampling area should be in a field < 15 acres in size.
2. Take samples from 15 different areas in field to provide a look at management and soil type impact.
3. Collecting samples will require use of tape measure, side cutters or plant pruners.
4. A Pre-Harvest sample should be taken from 6-14 inches from the ground and sample segment should be 8 inches long.
5. A Post-Harvest sample should be taken from 2-8 inches from the ground and sample segment should be 6 inches long.
6. Quarter samples into 4 pieces and submit one quarter for testing purposes. There should be a total of 15 quarters collected.
7. Do not allow sample segment to become contaminated with soil, as it may impact proper test results.
8. Samples should be placed in a paper bag to allow some drying but prevent the growth of mold. Do not freeze sample. Ship samples to lab within 24 hours.

Please include a completed copy of CSNT Sample Submission Form when submitting samples.

CSNT Interpretation

Work with your agronomy consultant or other certified crop professional after receiving results to establish a N program for your corn fields.