Farm Talk

Front page stories

September 25, 2013

Stalk Nitrate-N Test — A tool for evaluating nitrogen in corn

Parsons, Kansas — With the increase in N fertilizer prices, and growing concern for environment growers are becoming more interested in fine tuning fertilizer N applications for corn production. There are many diagnostic tools that are available for improving N management in corn. Researchers at Iowa Sate University have come up with the stalk nitrate N test as a diagnostic tool in improving N management in corn (www.n This test gives you information on how well you have managed your nitrogen and doesn’t provide information on how much fertilizer N to apply for the coming season.

The stalk Nitrate N test is done in the lab where a 6” stalk (samples should be cut at 6-8” above the soil surface, at black layer stage, no leaves included) sample is dried, ground, and processed and analyzed for nitrate-N. The numbers are compared to standards set by Iowa State University researchers based on field research. It is important to note for accurate results samples should be collected at one to three weeks after 80 percent of the kernels reach black layer stage (physiological maturity) and not after harvest.

After collecting a representative sample 6” stalk samples cut 6–8” above the soil surface, make sure to split the sample into two vertically and let it dry before mailing it to the lab. This would quicken the process of drying. It is preferable to sample a least a minimum of 10 stalks from the area of interest to have good representation and reliable results.

In general, larger amount of plant available N in the soil during the time period before plant maturity results in higher concentration of nitrates in the lower portion of the stalk. However, stalk nitrate-N can be greatly influenced by other factors like soil moisture and precipitation.

A stalk NO3-N test value of less than 250 ppm is interpreted as low, nitrogen was probably deficient during the growing season. Test values of 250-700 ppm is marginal, it is possible that nitrogen shortage limited yield in this range, and 700-2000 is optimum, yield was not limited by a shortage of nitrogen in this range. Values in excess of 2000 ppm means excessive, nitrogen rate was too high or some production factor caused a yield reduction. Factors other than excessive use of N can such as drought and hail damage can lead to excess N in the stalk.

University of Missouri Soil and Plant Testing lab located at 23 Mumford Hall, UMC, Columbia, MO 65211 offers stalk NO3-N test in corn for $10 per sample. You can reach the lab at 573-882-0623 or get information from the lab’s Website at http://soilpl on submitting samples. When submitting samples corn stalk Nitrate-N test, use the plant analysis form http://soil and select Nitrate-N test. There is sample grinding fee for processing the samples. If you have any other questions about the test you can contact Manjula Nathan at 573-882-3250. £

Text Only
Front page stories
  • shoup_coltrain_0028.jpg Big chill, little damage in SE Kan. corn fields

    Corn seedlings turned brown by recent cold temperatures had growers speed-dialing their crop insurance agents last week.
    For most, though, it may be one of those “not-as-bad-as-it-looks” situations.
    K-State Agronomy Specialist Doug Shoup and Wildcat Extension District agents Josh Coltrain and Keith Martin were out in fields late last week surveying the situation.

    April 22, 2014 5 Photos

  • StockersFP.jpg USDA beefs up production forecast

    In USDA’s latest forecast, total meat production is predicted to be lower in 2014 despite higher beef production and price expectations.
    And on the crop side, the World Agricultural Supply and Demand Estimates report, issued April 9, helped ease fears of lower crop prices.

    April 15, 2014 2 Photos

  • el_nino.jpg El Niño return likely but little crop impact expected — for now

    Long-range weather forecasters expect an El Niño return sometime this year but its timing and strength are still beyond the reach of reliable predictability.
    Odds for an El Niño occurrence increase as temperatures warm in the Pacific. Above-average sea surface temperatures are currently being measured over much of the eastern tropical Pacific.

    April 15, 2014 1 Photo

  • Jim_McCann_0001.jpg Speaking up for beef

    Jim McCann wants cattlemen to have a seat at the table — and he wants beef to be the main course.

    April 8, 2014 1 Photo

  • prescribed_burn.jpg Activity heats up on the prairie when you’re going to grass

    Going to grass is always an exciting time, but getting ready for it is lots of hard work that involves far more than opening a gate.
    And most of it happens well ahead of green-up.

    April 8, 2014 1 Photo

  • RoddMoesel_cmyk.jpg Gardens are gateway to agriculture says Okla. Hall of Famer

    April 1, 2014 1 Photo

  • Enlow_tractor.jpg Enlows celebrate half-century heritage

    March 25, 2014 1 Photo

  • HF_14_shooter_0161.jpg HorseFest sizzles Springfield with huge trade show, education and entertainment

    Internationally-known horseman Guy McLean set the bar high at last week’s HorseFest in Springfield, Mo., and a full slate of savvy horsemen and women, hot competition and the area’s biggest equine trade show added up to a great weekend for thousands of area equine enthusiasts.

    March 25, 2014 5 Photos

  • KSU-Sylvester.jpg Area families earn ‘Master’ honors

    March 18, 2014 3 Photos

  • Bradshaw_tractor-025.jpg An answer to a prayer

    “If you give a man a fish you feed him for a day, but teach him to fish and he will eat for a lifetime.” Applying those words to real life became an answer to a prayer for Carthage, Mo., farmer Larry Peters, and the Fairview Christian Church.

    March 11, 2014 4 Photos

Hyperlocal Search
Premier Guide
Find a business

Walking Fingers
Maps, Menus, Store hours, Coupons, and more...
Premier Guide
Seasonal Content