What is in this article?:
- Late-season nitrate test helps fine-tune corn fertilization
- Video demonstrates procedure
• The test provides a good assessment of whether the corn crop had the right amount of nitrogen, too much nitrogen, or whether it ran out of gas.
• This information combined with records of nitrogen management can be very useful for making and fine tuning future nitrogen and manure management decisions.
The Late-Season Cornstalk Nitrate Test (LSSNT) has been demonstrated to be a reliable end-of-season indicator of crop nitrogen status.
It provides a good assessment of whether the crop had the right amount of nitrogen, too much nitrogen, or whether it ran out of gas.
This information combined with records of nitrogen management can be very useful for making and fine tuning future nitrogen and manure management decisions. See Agronomy Factsheet #70 Late Season Cornstalk Nitrate Test (http://cropsoil.psu.edu/extension/facts/agfact70.pdf) for all of the details.
Sampling
For the test results to be valid the sampling instructions must be followed carefully. Samples for this test should be taken between ¼ milk line and up to 3 weeks after black layer.
An 8-inch long section of corn stalk starting 6 inches above the ground is collected from at least 10 representative plants in a field. After the sample is collected the stalk segments should be cut into shorter pieces to promote drying and then sent to the lab for analysis.
