237 



CHAPTEE X. 



WOOD-ASII. 



The amoimt of the food of plants in it — Box-wood ash gives only the half 

 of its potash readUy to water — Convenience in mixing wood-ash with 

 earth before applying it — Lixiviated ash, its value — Proper mode of 

 applying ashes as a manure. 



IT lias already been stated that the proportion of potash 

 is very dissmiilar in different wood ashes ; those 

 from hard wood bemg generally richer in that substance 

 than those from soft wood. The ash of beech-wood 

 gives up to water the one-half of the potash in it, in the 

 form of carbonate of potash, the other half remaining in 

 combination with carbonate of hme, in a compound which 

 is only very slowly decomposed by cold water. The ash 

 of pine-wood generally contains, hke tobacco ash, a 

 larger proportion of lime, so that cold water often seems 

 to fail altogether in dissolving any carbonate of potash 

 out of it. However, the continued action of water suc- 

 ceeds always m gradually extracting from all these ashes 

 the whole of the potash ; and since they can be easily 

 ploughed deeply in, they are suited better than all other 

 potash compounds to enrich with that alkah the deeper 

 layers of tlie arable soil. With wood-ashes that part 

 readily with their potash to water, it will be found useful 

 to mix the ash, before applying it, with an earth that 

 absorbs potash, adding so much of the latter that water 

 poured upon the mixture will no longer turn reddened 



