The Story-Book of the Fields 



soon as the heaps are cold the mixture of 

 ashes and burnt earth is spread over the 

 surface of the ground with a shovel. This 

 operation is called clearing ; and by this 

 means a piece of ground, which has never been 

 cultivated and which is covered with its wild 

 plants, is rendered fit for use. 



This clearing produces two effects, one of 

 which relates to the clay in the ground and the 

 other to the ashes produced by burning the 

 weeds. Clay, as you know, is a tough and 

 sticky substance which cannot be penetrated 

 by air or water. Therefore ground which 

 holds too much clay is unfavourable to the 

 growth of plants, the roots of which always 

 need air and moisture. But as soon as it has 

 been strongly heated clay will have very 

 different properties. It no longer combines 

 with water, it is porous and permeable and 

 easily penetrated by air and water. So burn- 

 ing the weeds improves a clay soil by burning 

 the clay and making it permeable. This 

 shows that although this is excellent for a 

 heavy clay soil it is bad for poor or sandy 

 ground. 



The ashes of the weeds also produce their 

 effect. After the complete combustion of 

 any vegetable matter, an earthy powder or 



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