122 



Partial Sterilisation of Soil 



Table 1. Crop results obtained on partially sterilised soils. 

 1st crop, Rye. 



2)ul crop, BuckwJieat. 



Untreated.. 



Heated 



Toluened .. 



•18 

 •22 

 •16 



The treatment was then repeated, and wheat was grown. The crop 

 is still standing, but the differences are of the same order as those 

 obtained with rye. 



Plate VIII, Fig. 1 shows the rye and Plate VIII, Fig. 2 the wheat 

 crops. On reference to the earlier paper it will be found that these 

 results, obtained on an exhausted soil, are very similar to those obtained 

 on fertile soils. The crops grown on heated soils are shorter in the straw 

 and more compact than the others ; typical internodal lengths in cms. 

 are : 



The chemical changes taking place after partial sterilisation. 



§ 14. Two soils have been used in these experiments : the Barnfield 

 soil, alluded to above, and a soil from the outside strip of Little Hoos 

 which had until 1902 been in ordinary arable cultivation, and since that 

 year has carried the same crop as the rest of the field, but has had 

 occasional dressings of artificial manures. The two soils contained : 



