CHAPTER VI 



THE PLANT FOOD IN THE SOIL 



Apparatus required. 



The pot experiments {p. xiii). 



It is a rare sight in England to see land in a natural 

 uncultivated state devoid of vegetation. The hills are 

 covered with grasses and bushes, the moors with ling 

 and heather, commons with grass, bracken and gorse, 

 a garden tends to become smothered in weeds, and 

 even a gravel path will not long remain free from grass. 

 It is clear that soil is well suited for the growth of 

 plants. We will make a few experiments to see what 

 we can find out about this property of soil 



We have seen that a good deal of the soil is sand or 

 grit, and we shall want to know whether this, like soil, 

 can support plant life. We have also found that the 

 subsoil is imlike the top soil in several ways, and so we 

 shall want to see how it behaves towards plants. Fill 

 a pot with soil taken from the top nine inches of an 

 arable field or untrenched part of the garden ; another 

 with subsoil taken from the lower depth, 9 to 18 inches, 

 and a third with clean builder's sand or washed sea- 

 sand. Sow with rye or mustard, and thin out when the 

 seeds are up. Keep the pots together and equally well 

 supplied with water ; the plants then have as good a 

 chance of growth in one pot as in any other. 



