FARGO, N.D. — What does a university professor accomplish across a 40-year career? Besides his world-renowned efforts in iron deficiency chlorosis, R. Jay Goos at has worked in these other areas at North Dakota State University:


The "No. 2" crop in the state of North Dakota in 1980 was not a crop at all but "summer fallow," the practice of idling ground in an effort to save soil moisture.

Summer fallow worsened the phenomenon of “saline seeps” in western North Dakota and eastern Montana. Rains falls on hilltops and drive naturally-occurring “salts” into the water table that “seep” out of the side of a hill. They emerge as white salt deposits where crops won’t grow.

Goos and colleagues came up with nitrogen and water management recommendations to counter. This involved moving away from a spring wheat-fallow rotation.

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“Because of no-till methods, almost nobody fallows anymore,” he says.

In the dry years back then, they recommended if there was greater than 4 inches of stored soil water at planting, they should not fallow, or leave the soil idle and bare. They could recrop with another crop..

They also identified an “N factor” — the sum of the soil fertilizer plus the supplemental fertilizer to acquire a maximum wheat yield. The factor was 2.5 pounds of soil nitrogen plus supplemental fertilizer nitrogen per bushel of expected yield. They also established the protein content as a post-harvest indicator of the nitrogen sufficiency.


Barley farmers applying "potash" — potassium chloride — saw yield increases even on fields high in available potassium. Pacific Northwest researchers had seen yield increases from chloride applications, especially when fields were infected with "take all root disease."

For farmers in the Upper Great Plains, Goos and colleagues verified that chloride would reduce root diseases by applying potassium chloride, compared to delivering the potassium as potassium sulfate. The benefits of chloride fertilization on barley health and yield were confirmed with subsequent studies.

“Chloride fertilization is accepted now, but it wasn’t at the time,” Goos says.


In 1985, NDSU flew scientists to Pendleon, Ore., to learn from U.S. Department of Agriculture researcher Betty Klepper, who was establishing the Klepper/Haun method of describing wheat plant development. Goos has used this method ever since. He showed that for yields up to 70 bushels per acre, the main stem and the first two “tillers,” (T1, and T2) account for 90% to 100% of the yield.

Goos linked plant tiller development stages on phosphorus studies to compare the effects of starter fertilizer and seed inoculants. He also used this method to study fall nitrogen and overwinter losses, as well as responses to slow-nitrifying fertilizers.


Goos studied and proved the effects of fertilizer additives to reduce the loss of fall-applied nitrogen over winters, especially in winters with heavy snowfall.

From 1985 to 2013, Goos published nine scientific papers on the use of ammonium thiosulfate (ATS), a common sulfur fertilizer, and its effect as an urease inhibitors — slowing enzymes from hydrolyzing urea nitrogen fertilizer into carbon dioxide and ammonia, and nitrification.

He found these inhibitors are effective when applied in concentrated bands or “dribbled” as a surface application.

Later, Goos studied the effects with average, bare soil and straw treatments, as well as small- to large-droplet sizes.

He compared two nitrification inhibitors and found that ATS, when banded can slow ammonia loss, but isn’t as effective as the commercial urease inhibitor Agrotain.

“If you are using UAN, and need S, you may also get some nitrogen conservation benefit from using ATS,” he says.


Nitrogen in soybeans flows from the roots to the tops in two forms — nitrate from soil solution, or “ureides” from the root nodules where nitrogen fixation occurs. Bacteria in the nodules convert nitrogen gas from the atmosphere into ammonia. Plant cells convert ammonia into ureides.

Goos developed a simple chemical test for ureides, to determine if fixation is adequate for soybean growth. He also determined that the topsoil only needs about 50 cells of B. japonicum (the soybean symbiotic bacterium) for adequate nodulation. Most fields that have been used to grow soybean several times already have thousands per gram. After growing soybeans a few times in rotation, inoculation is not needed.