5° BOTANICAL GAZETTE [SEPTEMBER 
not be very significant, except as another way of comparing the 
sulphur content of the different groups of soils. 
The sulphur content of maximum yields of the six crops given 
in table VIII, according to the figure of BRown and KELLOGG, 
totals 134.3 pounds; the total phosphorus content 128 pounds. 
These are five of the most common crops, especially in the central 
states. Judging from the soil analyses that have been made by 
TABLE VIII 
NUMBER OF MAXIMUM CROPS THAT MAY BE GROWN FROM AMOUNT OF SULPHUR PRESENT 
THE FIVE SOIL GROUPS AS GIVEN IN TABLE VII 
Alabama | Maryland| Range | Oklahoma ost Range | Chicago 
GEG cere 16 28 oy eee iy 30 37 20-7 76 
Wheat... 574. : 25 45 35-58 47 58 41-113} 119 
Rt Ce ea 15 27 21-36 20 36 25-70 73 
Potatoes: yi 2.4: Vd 14 II-I7 14 18 12-35 37 
Cover... 2k. 19 35 27-45 36 45 32-88 93 
Alfalfas. ooo. 5 Is 10 7-13 10 13 9-2 26 
various investigators, the agricultural soils of the United States are 
even more deficient in sulphur than in phosphorus. Although 
considerable sulphur is added to the soil of rainwater, a larger 
amount seems to be lost in drainage, some investigators stating that 
three times as much sulphur is lost from the soil in drainage as is 
added to the soil by the rain. It would seem possible, therefore, 
that further investigation would prove that sulphur is as generally 
needed as a fertilizer as is phosphorus. 
EFFECT OF SULPHUR ON CHLOROPHYLL DEVELOPMENT, AND GROWTH 
OF RED CLOVER AND SWEET CORN 
Several investigators have reported a better color in plants 
due to sulphur fertilization. Rermmer and Tartar (21), as already 
stated, secured greatly increased yields of alfalfa from sulphur 
fertilizers. They emphasize the poor color of the alfalfa on the 
plats not fertilized with sulphur. Oxson (19) speaks of the same 
thing in connection with experiments in Washington. The Massa- 
chusetts station (16) reports like results, but the beneficial effect 
on the color does not seem to be confined to the legumes. DULEY 
(6) reports the same thing in the case of sweet corn, and DEMOLON 
