472 



Journal of AgrictUtural Research 



Vol. XII, No. 8 



Tabi,E II. — Influence of calcium carbonate, limestone, and monocalcium phosphate on the 

 number of bacteria in Plainfield sand 



Treatment. 



Number of bacteria in i gm. of dry soil. 



After 1 

 week. 



Rela- 

 tive. 



After 2 

 weeks. 



Rela- 

 tive. 



Afters 

 weeks. 



Rela- 

 tive. 



Afters 

 weeks. 



Rela- 

 tive. 



After 2o 

 weeks. 



Rela- 

 tive. 



None 



One-fourth calcium 

 carbonate 



One-half calcium car- 

 bonate 



Full calcium carbonate. 



One-fourth limestone. . . 



One-half limestone 



Full limestone 



o.s gm. monocalcium 

 phosphate 



a gm. monocalcium 

 phosphate 



0.5 gm. monocalcium 

 phosphate -f one- 

 fourth calcium car- 

 bonate 



0.5 gm. monocalcium 

 phosphate -f- full 

 calcium carbonate . . . 



a gm. monocalcium 

 phosphate + one- 

 fourth calcium car- 

 bonate 



2 gm. monocalciimi 

 phosphate + full 

 calciiun carbonate 



10, 300, 000 



10, 000, 000 



6, 600, 000 

 6, 000, 000 

 5, 800, 000 

 8, 000, 000 

 9, 700,000 



8, soo, 000 



S, 000, 000 



16,000,000 

 12,000,000 



11,200,000 



97 



64 



3,500,000 



3,600,000 



4, 660, 000 

 60-5,520,000 

 56|4, 660,000 

 77 3,800, 000 

 94'4, 200, 000 



84 



4,200,000 

 4,200,000 



100 

 102 



130 



158 

 130 

 109 

 120 



120 



120 



120 



80 



5,500,000 



6, 000, 000 



11,200,000 

 18,300,000 

 11,000,000 

 10,000,000 

 9, 700,000 



5,700,000 



8,900,000 



14,500,000 

 9,400,000 



9,300,000 



150 10,300, 000 



100 4 

 10916 



203 7, 

 3327. 

 200 8, 

 180! 7, 

 17617, 



700,000 



600,000 



700,000 

 300, 000 

 500, 000 

 700, 000 

 200, 000 



263 



4, 100, 000 

 3,200,000 



8, 000, 000 

 6, 800, 000 



6,600,000 



164 

 155 

 181 

 164 

 154 



87 



68 



170 

 144 



140 



172 



2,450,000 



4, 850, 000 



4 330,000 

 5, 800, 000 

 4, 000, 000 

 3,000,000 

 4,530,000 



2, 650, 000 



2,000,000 



3,120,000 

 7,770,000 



3,410,000 

 3,660,000 



197 



IJ2 

 236 



i6i 

 12a 

 184 



loS 



83 



86 

 317 



139 

 148 



12 3 4 5 6 7 



I z i ^ s b t 

 Z U/eeHi 



I Z i 4 5 6 7 



3 WeeAs 



12 3 4 5 6 7 

 6 U/eehi 



ZOU/eehs 



Flo. a. — Diagram showing the influence of calcium carbonate and monocalcium phosphate on the number 



of bacteria in Colby silt loam. 

 i=no treatment. 



2=0.5 gm. monocalcium phosphate. 



3=2 gm. monocalcium phosphate. 



4=0.5 gm. monocalcitmi phosphate -f-one-fourth calduza carbonate. 



5=0.5 gm. monocalcium phosphate-1-fulI calcium carbonate. 



6="2 gm. monocalcium phosphate -f one-fourth calcium carbonate. 



7— a gm. monocalcium phospbate-l-full calcium carbonate. 



