Pre-Sidedress Soil Nitrate Test Will Save Money On Nitrogen Fertilizer

UPDATED: April 12, 2013

Pre-sidedress soil nitrate test (PSNT) is an excellent tool to determine the available soil nitrogen (N) on fields that have a high N mineralization potential. These are fields that have a previous history of manure or alfalfa. Studies have shown that farmers could reduce their N fertilizer application rate on corn without risking yields if the test is properly carried out. With the price of N fertilizer rising, growers may be able to save an average of $50/A based on this test.

Some prep work is necessary to achieve the desired results from the PSNT. Here are some points to remember:

  • The test is ideally suited for fields with high N mineralization potential (i.e., fields with high organic matter, manure or legumes). Other fields that will have high nitrate levels are loam, clay loam and clay soils that have been heavily fertilized in previous years. The test measures both residual nitrate N from the previous year and recently mineralized N from organic matter.
  • No broadcast or incorporated preplant N fertilizer should be applied. A modest amount of starter N up to 40lbs/A could be band applied near the seed.
  • The greatest amount of available soil nitrate usually occurs in the soil once the soil has warmed up and about three to four weeks after corn emergence (V6 to V8 growth stage). At this stage, corn begins to take up N quite rapidly. This is the most appropriate time to apply sidedress N. Since N release from mineralization is an ongoing process, collecting PSNT soil sample as close to sidedress date gives the best information about the appropriate N credit. It takes a few days to collect the samples and get them analyzed.
  • Soil samples taken earlier will not give a full measure of mineralizable N. Therefore, the amount of N credit will be smaller.
  • Soil cores should be taken midway between the corn rows, avoiding the starter fertilizer band. The sampling depth is 12 inches. Each sample should be a composite of 15 to 20 soil cores and represent no more than 20 acres.
  • Air-dry the sample in paper bags near a fan or heated air vent. Drying the sample is very important. Do not place soil in plastic bags.
  • The test will measure the nitrate concentration in parts per million (ppm). The critical level is 25 ppm, above which no N fertilizer is recommended. When the concentration is below 25 ppm, the N fertilizer recommendation is adjusted accordingly.

For more information, see Michigan’s Soil Nitrate Test for Corn.

Leave a Reply

One comment on “Pre-Sidedress Soil Nitrate Test Will Save Money On Nitrogen Fertilizer

  1. Great article! Solum has created a mobile tool for measuring nitrates in soils. This tool is designed to help services providers support the in-seasons PSNT market. We also just released a mobile app to help our customers provide even faster end-to-end support. The app is available on iOS http://tinyurl.com/b5su2ro and Android http://tinyurl.com/avo93d5 
 If anyone is interested, feel free to call 1-855-GO-SOLUM to find a service provider near you.

Fertilizer Stories
FertilizerFall Fertility 2014: Forecasting Fertilizer Use
September 7, 2014
Great crops this year have tapped the soil, and fall work is definitely called for, but how challenging will that get? Read More
Aerial view of the West Fertilizer explosion site
FertilizerFertilizer Companies Blame City For West, TX, Explosion
August 6, 2014
El Dorado Chemical Co. and CF Industries contend the city failed to properly train the first responders and had insufficient protocols in place to battle the April 17, 2013, blaze at West Fertilizer Co. that triggered the explosion. Read More
FertilizerThe Fertilizer Institute: New President, Renewed Energy
February 3, 2014
Chris Jahn relishes the opportunity to lead the organization through the challenging times ahead. Read More
FertilizerA New Cycle For Fertilizer Demand
January 2, 2014
Changes in the corn market could have a major impact on the crop nutrients sector in 2014, say experts. Read More
Top 100 Articles
CropLife 100BRANDT Commemorates National Ag Day
March 20, 2015
The Illinois agriculture community gathered at BRANDT global headquarters on March 18 to celebrate National Ag Day behind this year's theme Sustaining Future Generations. Read More
Wheat Growers, North Central Farmers Elevator Pursue Merger
CropLife 100Wheat Growers, North Central Farmers Elevator Pursue Merger
March 3, 2015
Two CropLife 100 retailers — South Dakota Wheat Growers (ranked No. 11) and North Central Farmers Elevator (No. 19) — have entered into a Letter of Intent to unify the two companies into a newly named cooperative. Read More
Growmark Group
CropLife 100GROWMARK In 2015: Back, To The Future
March 2, 2015
The nation’s third largest ag retail organization is simultaneously moving forward while remembering its past. Read More
CropLife 100Pinnacle Expands Sanders Brand In The South
February 27, 2015
Pinnacle has acquired Hopkins Seed and Chemical in Qulin, MO, which expands the company's Sanders brand to nine Southern states. Read More
CropLife 100Pinnacle Launches New Providence Agriculture Location In Indiana
February 27, 2015
Pinnacle Agriculture Holdings — ranked No. 6 on the CropLife 100 — has established a new retail location in New Castle, IN, which will operate as part of Pinnacle's Providence Agriculture brand. Read More
Carl Casale of CHS
CropLife 100Cooperative CHS Returns $518 Million To Owners
February 23, 2015
The 2015 cash return to owners is based on CHS net income of $1.1 billion, the company's second highest on record. Read More
Latest News
HerbicidesNew EPA Glyphosate Restrictions Leaked To Reuters
April 1, 2015
U.S. regulators will put new restrictions on the world’s most widely used herbicide to help address the rapid expansion of Read More
FMC 3Rive 3D
Seed/BiotechFMC’s 3RIVE 3D Turns Heads
April 1, 2015
As winter trade shows tend to go, Commodity Classic tends to be a pretty big deal. You’ve got all the Read More
Nachurs Alpine Solutions, Liquid fertilizer, micronutrients, facility
MicronutrientsYara Launching YaraVita Procote Liquid Micronutrients
March 31, 2015
Yara North America, Inc. broadens its fertilizer coating offerings with the introduction of YaraVita Procote, oil-based micronutrient liquid suspensions that Read More
Industry NewsINCOTEC Board Member To Retire
March 31, 2015
JanWillem Breukink has decided to retire from his position on INCOTEC’s Board of Directors, effective April 1, 2015. This was Read More
MicronutrientsAgrium Deals Michigan Micronutrient Facility To Cameron…
March 31, 2015
Cameron Chemicals, Inc. has announced today that it has entered into a definitive agreement with Agrium Inc. to purchase the Read More
Industry NewsH.J. Baker Creates, Fills New Pacific Northwest Sales P…
March 30, 2015
H.J. Baker announced today that Gary Bingham has joined the company’s Crop Performance Division to further deepen its sales portfolio Read More
Algal blooms
StewardshipStudy: Algae From Clogged Waterways Could Be Used As Bi…
March 30, 2015
Water-borne algal blooms from farm fertilizer runoff can destroy aquatic life and clog rivers and lakes, but scientists are reporting Read More
Young corn plants
Stewardship4R Nutrient Stewardship Summit Coming To DC
March 30, 2015
The annual 4R Nutrient Stewardship Summit will be held on May 12 in Washington DC. The summit will include a full Read More
FungicidesSyngenta Suing Willowood Over Azoxystrobin Fungicide
March 27, 2015
Syngenta announced today that it has sued agrochemical maker Willowood, LLC., for patent and copyright infringement, as well as unfair Read More
ManagementRetail Week: The Future Of Mycogen Seeds; The 4Rs At Na…
March 27, 2015
Editors Eric Sfiligoj and Matt Hopkins discuss recent trips, including a look at the future of Mycogen Seeds at Dow Read More
Eric SfiligojMonsanto Hears The WHO
March 27, 2015
Another challenge to the safety of glyphosate, and the responses from supporters and opponents, calls to mind a classic Dr. Seuss story. Read More
Industry NewsMonty’s Plant Food Expands Sales Team
March 27, 2015
Monty’s Plant Food Company, a leader in natural soil enhancement and  plant fertility products, has hired Andrew Bullock as a Read More
Crop InputsSyngenta Louisiana Plant Poised For 2015 Production
March 26, 2015
As the 2015 planting season gets underway, growers across the country will need crop protection products to combat pests and Read More
Lake Erie Nutrient Stewardship
LegislationOhio Lawmakers Finalize Phosphorus Restrictions
March 25, 2015
State lawmakers on Wednesday finalized new rules designed to curb toxic algal blooms on Lake Erie, calling the regulations a major step forward in addressing the problem. Read More
Spreaders17 Fertilizer Spreaders For 2015
March 25, 2015
Manufacturers shoot for versatility and accuracy in this year's crop of fertilizer spreaders. Read More
Industry NewsMonty’s Hires Mid-South Product Consultant
March 25, 2015
Monty's Plant Food Co. has hired Matt Woodring as a Product Consultant for portions of Central Kentucky and Tennessee.    Read More
StewardshipMapShots Integrates With DriftWatch
March 23, 2015
Growers and agricultural providers using AgStudio FARM and AgStudio PRO can now view vital information about specialty crops and apiaries through a recent integration with the DriftWatch Specialty Crop Site Registry from FieldWatch, Inc. Read More
Crop InputsWorld Health Organization Report Contradicts Scientific…
March 23, 2015
A new report from the World Health Organization has classified glyphosate with a “2A” rating as a probable carcinogen, a Read More