
100 | J. K. TAYLOR. 
accumulation. Buckman at Cornell, U.S.A., notes the big 
advantage gained by the cultivated fallow which stores 66 
p. pm. nitrate nitrogen compared to 14 p.pm. in the cropped ; 
land. Lyon and Bizzell at Cornell, N.Y. have found under 
their humid conditions immense amounts present, at times 
between 200 and 300 p.pm., and the average for the four 
summer months at about 50p.pm. These rather stagger- 
ing figures have no’ parallel under our climatic conditions 
and with the soil used. The main featuresin Table IV are 
without doubt the comparatively small amounts of nitrate 
present in the soils under investigation, and the demon- 
stration of the fact that the main activity of the nitrifying 
bacteria occurs in the summer months even despite the 
low moisture content of the soil. 
Nitrates in Subsoil. 
The greater part of the subsoil nitrates is probably 
derived from the surface soil through water action. Table 
V presents the figures for subsoil and there is little to 
commenton. The winter quantities average higher than 
the summer, and this is probably due to the heavy rainfall 
and the low evaporation. 
Table V.—WMitrate Nitrogen in Subsoil—9” to 18” as parts per 
million and ibs per acre 9". 

ae of | Grass. Lucerne. PA PB PC PD 


Sampling. ppm. Ibs. | ppm. tbs. | ppm. Ibs.| ppm. tbs. | ppm. lbs. /ppm. Ibs. 



1921 
July 14 |18:0 45:0/}.3°5 8-751 7-2 18-0) 7-8 19°5) 7:2 18-0/7-8 19°5 
Aug. 17 | |6:8 17:0) 2°4 60 14:0: 10-0) 2-84-02) Seb rao 
No Subsoil samples taken from September to November. 


Dec. 15 aac 2°87 { 3:7 9°3, | 22 31676) ees 
1922 
Jan. 11 “a: 2°9. 7:5.) 3:6. 9:0. | 271, 53. | 2 a8 
Feb. 15 Pi 270 5:0 | 2°3 5°8 | 2:0 5:0 | 2-2 5:5 


Mar. 16 ee 2-5 6°3 | 2:4 6:0 | 2:0 5:0 | 2°4 6:0 

