112 Fertilizers 



a form as to be immediately available to plants. Ashes 

 also have a very favorable physical effect upon soils, the 

 lime present, of course, aiding in this respect. Canada 

 is now the main source of wood-ashes, the substitution of 

 coal for wood making the supply in this country for 

 commercial purposes very limited. Owing to the vari- 

 ability of this product, it should always be bought sub- 

 ject to analysis, and to a definite price a pound for the 

 actual constituents contained in it, which should not 

 be greater than the price at which the same constituents 

 could be purchased in other quickly available forms. 



Because wood-ashes have given excellent results, many 

 attempts have been made to place them on the market 

 and to sell similar products under the same name, and it is 

 not uncommon to add to wood-ashes of low grade, fertilizer 

 materials to fortify the product and to sell it as a high- 

 grade material. This is especially true since the supply 

 has become inadequate to meet the demand; therefore, 

 great care should be exercised in its purchase. 



Tanbark-ashes are much poorer in fertilizing content than 

 those obtained from the regular commercial sources of sup- 

 ply. They seldom contain more than 2 per cent of potash, 

 1.5 per cent of phosphoric acid and 33 per cent of lime. 



Limekiln-ashes are obtained in the burning of lime with 

 wood, and are also relatively poor in potash, containing 

 less than 1.5 per cent of potash and 1 per cent of phosphoric 

 acid. The product is, however, much richer in lime than 

 the average wood-ashes, often containing as high as 50 

 per cent of calcium oxide. 



Coal-ashes. 



It is believed by many that coal-ashes, because of their 

 favorable effect upon many soils, also possess considerable 



