THE EARTH'S BOUNTY 



ample, in the chestnut and in most conifers 

 they are so fine as hardly to be seen with the 

 naked eye. Seasoning cracks which run across 

 the rings of growth always follow the lines of 

 these rays, while others most often follow 

 along some annual ring. 



" It is correct to speak of these rings of 

 growth as ' annual rings,' for as long as the 

 tree is growing healthily a ring is formed each 

 year. It is true that two false rings may ap- 

 pear in one year, but they are generally so 

 much thinner than the rings on each side that 

 it is not hard to detect them. Very often they 

 do not extend entirely around the tree, as a 

 true ring always does if the tree is sound. 

 Whenever the growth of the tree is inter- 

 rupted and begins again during the same sea- 

 son, such a false ring is formed. This hap- 

 pens when the foliage is destroyed by cater- 

 pillars and grows again in the same season, or 

 when a very severe drought in early summer 

 stops growth for a time, after late frosts, and 

 in similar cases. 



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