66 MAINE AGRICULTURAL EXPERIMENT STATION. I9OI. 



phosphoric acid of a superphosphate is in a form ready to be 

 assimilated by the growing plant, while that of wood ashes may 

 be practically insoluble and only slowly available to the plant. 



If plant food is not in an immediately available form the 

 material containing it may still possess manurial value. To 

 utilize all kinds of plant food at one's disposal is an important 

 item in farm economy. The classes of such materials more 

 or less accessible to the farmers of Maine are ashes, "mucks" 

 seaweeds and bones. Partly because of accumulated unpub- 

 lished analyses of samples sent to the Station by correspondents 

 and partly in answer to inquiries respecting the manurial value 

 of these materials, this bulletin has been prepared. 



Wood Ashes. 



Maine farmers are pretty well agreed as to the high value of 

 wood ashes as a fertilizer. The fertilizing value of wood ashes 

 is commonly attributed to the potash which they contain. While 

 the potash has the largest money value of the fertilizing con- 

 stituents of ashes, their agricultural value also depends upon the 

 not inconsiderable amounts of phosphoric acid and the large 

 amounts of lime which they carry. The importance of these last 

 constituents is indicated by the high value some farmers put 

 upon leached ashes as a manure, although in leaching nearly all 

 of the water soluble potash has been removed. The potash con- 

 tent of ashes varies with the kind of wood, the method of burn- 

 ing, and the care taken of the ashes to protect them from rain. 



The Ontario Agricultural College* has made quite a study of 

 the composition of the ashes of different woods. And while 

 these results, usually from single specimens, cannot be taken as 

 final, they are suggestive and instructive. Some of the more 

 important of these analyses are given in the table which follows. 



*Report Ontario Agricultural College and Experimental Farms, 1S96, pp.24-26. 



