10 Florida Agricultural Experiment Stations

of magnesium oxide and 40 pounds of chlorine per ton. The
following quantities of minor element materials were added per
ton: 1.9 pounds of borax, 3.8 pounds each of copper, manga-
nese and zinc sulphates.


 26 M ERE
 3" APPLICATION 1/2" APPLICATION NO IRRIGATION TIME OF APPUCATION

 24

 22

 20







 12
 6





 14 --__,.,__...._____.





 3/28 4/5 4/15 4/25 5/4 5/15 5/23 6/1 6/8 6/20 6/29 7/7

 Fig. 7.-Cumulative chart showing distribution of rainfall and irrigation
 during 1951 growing season for tobacco.

 Commercial grade fertilizer materials were used in preparing
 the fertilizer. The nitrogen was supplied by sodium nitrate,
 sulphate of ammonia and urea at equal rates of nitrogen. Phos-
 phoric acid was supplied by superphosphate containing the
 equivalent of 18 percent P20O. Potash (KsO) was supplied from
 48 percent sulphate and 60 percent muriate of potash. Only
 enough muriate was used to supply 40 pounds of chlorine. Ep-
 som salts containing the equivalent of 16 percent MgO was used
 to supply the 40 pounds of magnesium. The initial applications