September 25, 2007
By Jim Fawcett, ISU Extension Field Agronomist
high wheat prices are causing some to consider trying winter wheat for the
first time. Iíve found that most growers who make winter wheat a profitable
crop are good at marketing the straw. Maybe this isnít as critical with todayís
prices. For maximum yields the wheat should be seeded by October 1,
although mid-October seedings can be successful. Make
sure you can market the wheat. Soft red winter wheat is more suitable for
FALL STALK NITRATE TEST FOR CORN
A useful tool to help fine tune nitrogen management in corn is to use the fall stalk nitrate test. The ideal time to take the stalk samples is 1-3 weeks after black layer. Many corn fields may be beyond this window now, but later work done by Fred Blackmer indicated that sample can be taken later as well with similar results. An easy way to take the samples is right after harvest. An 8-inch segment of stalk with the leaf sheaths removed needs to be taken 6 inches above the soil. If the head is set to cut the stalks about 14 inches above the ground, the upper 8 inches of whatís left in the field can be cut off to be sent to the lab. It is recommended to send 15 stalk samples for each area being sampled. Iíve found the test to be especially useful on manured fields to identify where excess nitrogen was used or to make sure there was sufficient N. In areas where there were excess rain and nitrogen losses, the test can confirm the lack of N. Instructions for the test can be found at http://www.extension.iastate.edu/Publications/PM1584.pdf. If you choose to use the ISU lab, the form can be found at http://www.agron.iastate.edu/soiltesting/CSN.pdf.
If you have any questions, please feel free to contact the Iowa State University Extension Office.
Nondiscrimination Statement and Information Disclosures