40 
Journal of Agricultural Research 
Vol. XXIII, No, I 
impoverishing the soil except with respect to the elements omitted in the 
nutrient solution. Obviously the method can not well be applied to 
compact, clayey soils. 
CONCLUSION 
Sand drown, a chlorosis of tobacco involving both the green and the 
yellow pigments of chlorophyll, is due to magnesium deficiency and is 
markedly aggravated by an increased sulphur supply. For these reasons 
the use of potash salts of high purity (free from magnesia) and, especially, 
pure forms of the sulphate have resulted in serious damage to the crop. 
The need for magnesium is readily met by the use of sulphate of potash 
containing magnesia or by applying lime containing magnesia. One of 
the functions of organic matter of vegetable origin, as cottonseed meal, 
tobacco stems, and barn manure and of lime, is to furnish small quantities 
of magnesia to the plant through the growing season. The sand-drown 
disease of tobacco suggests that in interpreting fertilizer action the sul¬ 
phur, magnesium, and calcium commonly contained in “ complete ” 
commercial fertilizers should be taken into account as well as the nitrogen, 
phosphorus, and potassium. A method of conducting pot cultures in 
which the soil is leached with complete and incomplete nutrient solutions, 
as desired, gave good results in the investigation of sand drown and is 
suggested for use in the study of problems in fertilizer action. It remains 
to be determined to what extent the findings concerning sand drown of 
tobacco will apply to other crop plants. 
LITERATURE CITED 
(1) Garner, Wightman W. 
1907. THE RELATION OF THE COMPOSITION OF THE LEAF TO THE BURNING QUAL¬ 
ITIES of tobacco. U. S. Dept. Agr. Bur. Plant Indus. Bui. 105, 27 p. 
(2) Greaves, J. E., and Carter, E. G. 
1919. THE ACTION OF SOME COMMON SOIL AMENDMENTS. In Soil Sci., V. 7, no. 
2, p. 121-160, 2 fig. References, p. 152-160. 
(3) Jacob, A. 
1920. DIE BEDEUTUNG DKR MAGNESIA ALS DUNGENMITTEL. Ill Ztscbr. Angew. 
Chem., Tahrg. 33, Bd. 1, p. 292. 
(4) LoEw, Oscar. 
1899. THE PHYSIOLOGICAL ROLE OF MINERAL NUTRIENTS. U. S. Dept. Agr. Div. 
Veg. Physiol, and Path. Bui. 18, 60 p. 
(5) Ridgway, Charles S. 
1916. grain of the tobacco LEAF. In Jour. Agr. Research, v. 7, no. 4, p. 
269-288, 2 fig., pi. 15-17. Literature cited, p. 287. 
(6) Wheeler, H. j., and Hartwell, B. L. 
1905. MAGNESIUM AS a manure. In R. I. Agr. Exp. Sta. 17th Ann. Rpt. 
1903/04, p. 22 1-260. 
(7) WiLLSTATTER, Richard. 
1906. ZUR KENNTNISS DER ZUSAMMENSETZUNG DES CHLOROPHYLLS. In Liebig's 
Ann. Chem., Bd. 350, Heft p. 48-82, 2 tab. 
