Cvltivation cmd tillage 



03 



I 



and so it melts the snow more rapidly. But during 

 winter the grass land loses its heat more slowly, and 

 therefore it is warmer at the end of the winter than the 

 arable land, hence the snow melts more quickly. 



In Chap. V. it was pointed out that dark coloured 

 soils rich in humus are greatly favoured by gardeners 

 and farmers. The value of humus can easily be shown : 

 take a sample of soil from a garden that has for a long 

 time been well manured and another from a field close 

 by — next to it if you can — and find the amounts of 

 moisture present. Two soils at Rothamsted gave the 

 following results: — 



Humus, therefore, keeps the water in the soil and saves 

 it from being lost. 



Another beneficial effect of hoeing is to keep doAvn 

 weeds. Weeds overcrowd the plant, shut out light, 

 take food and water, and occupy space. Few plants 

 can compete against weeds, some fail very badly in the 

 struggle. Sow two rows of maize two yards apart; 

 keep one well hoed for a yard on each side and leave 

 the other alone to struggle with the weeds that will 

 grow. Fig. 44 shows the result of this experiment at 

 St George's School. At Rothamsted a piece of wheat 

 was left unhar vested in 1882, and the plot has not been 

 touched since; the wheat was allowed to shed its seed 



