Connecticut Agricultural Experiment Station New Haven, Connecticut Fertilizer Experiments With Tobacco TOBACCO STATION AT WINDSOR The Bulletins of this Station are mailed free to citizens of Connecticut who apply for them, and to other applicants as far as the editions permit. OFFICERS AND STAFF May, 1925. BOARD OF CONTROL. His Excellency, John H. Trumbull, ex-officio, President. Charles R. Treat, Vice-President. George A. Hopson, Secretary... Wm. L. Slate, Jr., Director and Treasurer. Joseph W. Alsop. Elijah Rogers... Edward C. Schneider. Francis F. Lincoln. Orange Mount Carmel .New Haven ...Avon Southington Administration. Chemistry: Biochemical Botany. Entomology. Forestry. Plant Breeding. Soil Research. Tobaco Sub-station at Windsor. W. E. BRITTON, PH.D., Entomologist in Charge; State Entomologist M. P. ZAPPE, B.S. PHILIP GARMAN, PH.D. Assistant Entomologists. ROGER B. FRIEND, B.SC., Graduate Assistant. JOHN T. ASHWORTH, Deputy in Charge of Gipsy Moth Work. WALTER O. FILLEY, Forester in Charge. DONALD F. JONES, S.D., Geneticist in Charge. M. F. MORGAN, M.S., Investigator PAUL J. ANDERSON, PH.D., Pathologist in Charge. THE WILSON H. LEE Co. N. T. NELSON and P. J. ANDERSON Nowhere in the world does tobacco receive so expensive a ration of fertilizer as in New England. About one-third of the entire cost of producing tobacco here is the fertilizer item. Aside from the heavy cost, consideration of the fertilizer problem is extremely important because its composition affects the quality as well as the yield of cigar leaf. Yet, despite its vital importance to the tobacco grower, the investigation of commercial fertilizers for tobacco has received very scant attention from the experiment stations of New England. In the annals of tobacco growing in the Connecticut Valley, extending back for more than a century, there are found records of only two sets of fertilizer experiments. These two classical experiments were conducted thirty years ago at about the same time by Goessmann' in Massachusetts and Jenkins2 in Connecticut. Conditions have changed so much in the last thirty years, both in fertilizers and in tobacco growing, that a considerable part of the conclusions from these experiments may not be applicable to present times. There is need for a reworking of the whole field of commercial fertilizers for tobacco. There have been numerous fertilizer tests for tobacco in other sections of the country, but the results are of little value to the Connecticut grower because the type of tobacco grown is not the same, the soil and climate are different and the New England system of continuous cropping is different from that followed in other sections. The fertilizer experiments at the tobacco station at Windsor, were begun in 1922 by Dr. G. H. Chapman, and carried out under his direction until his resignation August 1, 1923. From that time until April 1924, they were continued by C. M. Slagg, and after April 1, by Dr. N. T. Nelson, physiologist in charge. These changes of administration have been unfortunate for the continuity of the experiments and have resulted in considerable loss since the data were recorded in different ways and are not supplemented by actual knowledge of their progress on the part of the present administration. Since a considerable mass of data has accumulated in the files it, as seemed best to publish all of it that is of significance in order to have on record all that has been done. With some modifications and additions the experiments are being continued and it is hoped that the data obtained from them will be published annually in the future. The data on the experiments of 1922 and 1923 are taken entirely from the reports of Dr. Chapman and Mr. Slagg and the present writers wish to give to them all credit for the work done. 1 Goessmann, C. A. On field experiments with tobacco in Massachusetts. Mass. Agric. Expt. Station. Bulletin 47:1-31, 1897. 2 Jenkins, E. H. Experiments in growing tobacco with different fertilizConn. Agric. Expt. Station Report 16:1-35, 17:112-114, 18:254284, 19:128-156, 20:285-333, 21:230-256 (1892-1897). ers. Limitations of available space and time to devote to it made it necessary to restrict the experiments at the beginning to an attempt to solve only a few of the problems involved. The experiments were divided into series as follows: 1. 2. 3. 4. 5. Nitrogen series. Comparison of different carriers of nitrogen. Phosphoric acid series. Comparison of different quantities of phosphoric acid. Potash series. Comparison of high grade sulfate of potash with double manure salt. Manure series. Comparison of different kinds of manure. Fractional application series. Comparison of fertilizer applied all at once with the same amount, or less, divided between several applications. 6. Sulfur-chlorine-magnesium series. The purpose of this experiment was to determine the effect of these elements on the tobacco.1 In the following pages each of these series is followed separately throughout the three years of the experiment. NITROGEN Series The tests in this series were designed to answer these questions: 1. Can all of the nitrogen be furnished to the plant from mineral carriers, nitrate of soda, nitrate of potash and sulfate of ammonia? 2. Can one-half of the nitrogen be supplied from these mineral sources, the other half being from cottonseed meal and castor pomace? 3. Can one-half of the nitrogen be supplied to advantage in dry ground fish? 4. Can one-half of the nitrogen be supplied in tankage? The advantage to be sought through the substitution of mineral for the organic sources of nitrogen is reduction in the cost of the fertilizer since the inorganic sources are only about one-half as expensive as the organic sources. In the case of fish, it was hoped also that there might be an improvement in the quality of the leaf It is the general belief among tobacco growers that the use of inorganic sources of nitrogen produces tobacco of poor quality. In Dr. Jenkins' experiments it was found that where castor pomace was compared with a ration in which one-half of the nitrogen was supplied by pomace and one-half by nitrate of soda, the latter fornula did not produce tobacco of as good quality as where castor pomace alone was used, but the yield was increased. In his experiments he also found that the use of fish scrap as the only source of nitrogen reduced the yield but gave a superior quality. He did not try fish in combination with other sources of nitrogen. This series in cooperation with the Office of Tobacco Investigations, United States Department of Agriculture. Not reported on in this bulletin. 2 Since the nitrate of soda was applied to the growing crop as a side dressing it is not possible to judge whether the results were due to mineral nitrogen or to fractional application. |