A comparison of nitrogen fertilizer additives

R. Jay Goos

Professor

Department of Soil Science

North Dakota State University

• Today, I’ll summarize

– My studies on ammonia loss inhibitors

– My studies on nitrification inhibitors

• First studies started in 1983

– Evaluated ATS as a urease and nitrification inhibitor for use with UAN liquid

• 5% ATS, Goos and Fairlie, 1988

• 5% ATS, Goos and Fairlie, 1988

• 5% ATS, Goos and Fairlie, 1988

• 5% ATS, Goos and Fairlie, 1988

ATS as a urease inhibitor

• Not a general-purpose urease inhibitor

– Works better with drier soils

– Works better with larger droplet sizes

– Works better on soil than on stubble

2008 study. Does Nutrisphere-N slow ammonia loss?

• Ammonia trapped in porous sponge containing phosphoric acid

• Franzen, et al. 2011

2010 study, ammonia loss inhibitors used with UAN

• UAN applied at about 100 kg N/ha, with and without various additives

• Experiment performed four times

– Small droplets, bare soil

– Large droplets, bare soil

– Small droplets, 50% stubble cover

– Large droplets, 50% stubble cover

• Goos (paper in review)

• 2011 study, many additives tested for granular urea

• Goos, 2011

Nitrification inhibitors

• Large urea granules + DCD

• Banded UAN studies

• Fall N studies

• Current studies

Spring banded UAN

Fall N with ATS or N-Serve

• Aqua ammonia banded in early October 1996 Record over-winter snowfall

• Soil samples taken late in fall, early spring

Ammon. in bands Wheat Total N

Late Oct. Mid-May Yield Uptake

ppm N bu/A lb/A

Control 2 3 23.6 34.6

Aqua 43 1 37.1 52.9

Aqua + ATS 65 11 47.4 77.0

Aqua + N-Serve 72 14 45.1 72.2

• Goos and Johnson, 1999

2011 nitrification studies

• Urea granules incubated with soil

• Studies still being conducted

• Goos, 2011

To summarize many, many experiments….

• Reactions of nitrogen in the soil are very difficult to inhibit

• If you need an inhibitor, use the strongest one available

• Papers cited, and related papers, listed below.

• All papers available in PDF format upon request: rj.goos@ndsu.edu

• Goos, R.J. 201x. Effect of fertilizer additives on

ammonia loss after surface application of urea-

ammonium nitrate fertilizer. Communications in Soil

Science and Plant Analysis (in review).

• Goos, R.J. 2011. Nitrogen fertilizer additives, which

ones work? Proceedings of the North Central

Extension-Industry Soil Fertility Workshop.

• Franzen, D., R.J. Goos, R.J. Norman, T.W. Walker,

T.L. Roberts, N.A. Slayton, G. Endres, R. Ashley, J.

Staricka, and J. Lukach. 2011. Field and laboratory

studies comparing Nutrisphere-Nitrogen urea with

urea in North Dakota, Arkansas, and Mississippi.

Journal of Plant Nutrition. 34:1198-1222.

• Goos, R. J. and B. E. Johnson. 1999. Performance of

two nitrification inhibitors over a winter with

exceptionally heavy snowfall. Agronomy Journal

91:1046-1049.

• Goos, R. J., J. A. Schimelfenig, B. R. Bock, and B. E.

Johnson. 1999. Response of spring wheat to

nitrogen fertilizers of differing nitrification rate.

Agronomy Journal 91:287-293.

• Goos, R. J. and Antonio de Padua Cruz. 1999. Effect

of ammonium sulfate pretreatment on ammonia

volatilization after urea fertilization. Communications

in Soil Science and Plant Analysis 30:1325-1336.

• Goos, R. J. and B. E. Johnson. 1993. Effect of urea

pellet size and dicyandiamide on residual ammonium

in field microplots. Communications in Soil Science

and Plant Analysis 24:397-409.

• Goos, R. J. and B .E. Johnson. 1992. Effect of

ammonium thiosulfate and dicyandiamide on residual

ammonium in fertilizer bands. Communications in

Soil Science and Plant Analysis 23:1105-1117.

• Goos, R. J. and T. E. Fairlie. 1988. Effect of

ammonium thiosulfate and liquid fertilizer droplet

size on urea hydrolysis. Soil Science Society of

America Journal 52:522-524.

• Fairlie, T. E. and R. J. Goos. 1986. Urea hydrolysis

and ammonia volatilization characteristics of liquid

fertilizer mixtures. II. Studies under modified field

conditions. Journal of Fertilizer Issues 3:86-90.

• Goos, R. J. 1985. Urea hydrolysis and ammonia

volatilization characteristics of liquid fertilizer

mixtures. I. Laboratory studies. Journal of Fertilizer

Issues 2:38-41.

• Goos, R. J. 1985. Identification of ammonium

thiosulfate as a nitrification and urease inhibitor. Soil

Science Society of America Journal 49:232-235.