Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Plants, Soils, and Climate

Committee Chair(s)

D. W. Pittman


D. W. Pittman


Winter wheat, with an annual average acreage of about 300,00o acres, forms an integral part of the farm economy of Utah. For many years intermountain agronomists and farmers alike have known dry-land wheat production to be limited by low summer rainfall. In the past 15 years, however, it has become apparent through intelligent research that in many cases lack of nitrogen has been the limiting factor. When this occurs, winter wheat production can be increased by correcting this nitrogen deficiency. It has also become apparent that a lack of nitrogen is responsible for much of the ppor quality wheat received by wheat processors form certain areas of the United States. To supple the neede nitrogen broth commercial fertilizers and green-manure crops have been used, but of particular importance at this time are commercial fertilizers. Unitl 1949 investigators of this problem used soil applications of either organic or inorganic nitrogen fertilizers in their studies. In that year Finney and Shellengerger (Kansas State College) began the first of their tests using "NuGreen" a synthetic urea fertilizer containing 44% nitrogen, as a foliage spray. Other experiemtns have shown that if large amounts of nitrogen fertilizer are added to dry farm wheat during a dry year, the yield may actually be reduced because the early vegetative growth is stimulated and the limited soil moisture is not able to bring about satisfactory maturity. It would seem that if nearly all of the nitrogen were withheld until the what was nearly mature, and then added as a spray, the danger of excessive early stimulation might be avoided while the protein content of the wheat might be increased. The results obtained by all of these tests were encouraging enough to warrant a study here in Utah of winter wheat fertilization involving the use of "NuGreen". It was proposed that the study be conducted on dry lands representative of intermountain conditions, and that it cover a two-year period. It was inteded that in the first year a preliminary of "feeler" test would be conducted to determine whether or not it was feasible to spray nitrogen on wheat. The intent was, that if favorable resutls were secured, this preliminary test would be followed in the second year by a more extensive study to obtian detailed information as to what effect urea spray might have on winter wheat. Objectives of these studies were: 1. To find the stage of maturity of the wheat plant at which urea spray would give the greatest protein increase. 2. To fidn the stage of matureity of the wheat plant at which urea spray would give the greatest yield increase. 3. To determine what amount of nitrogen, when supplied as urea, would tive the greatest stimulus to yield and protein, or both. 4. To compare the accepted practice of supplying nitrogen by soil application with the new method of adding it as a foliage spray.