MANURES. 125 



nable for mulching * young trees and plants -when 

 first set out. 



SAWDUST AND SOOT. 



/Sawdust in its natural state is of very little value 

 to the land, but when decomposed, as may be done 

 by the same method as was described for tan-bark, 

 it is of some importance, on account of the carbon 

 that it contains. Its ash, too, which becomes avail- 

 able, contains soluble earthy matter, and in this 

 way it acts as a direct manure. So far as concerns 

 the value of the ash, however, bark is superior to 

 sawdust. Sawdust may be partially rotted by mix- 

 ing it with strong manure (such as that of the hog- 

 pen), while it acts as a divisor, and prevents its too 

 rapid action when applied to the soil. Some kinds 

 df -a\vdu>t, such as that from beech-wood, form acetic 

 acid on their decomposition, and these should be treat- 

 ed with, at least, a sufficient quantity of lime to cor- 

 rect the acid. 



Soot is a good manure. It contains much carbon, 

 and has, thus far, all of the beneficial effects of char- 

 coal dust. The sulphur, which is one of its consti- 

 tuents, not only serves as food for plants, but, from 

 its odor, affords a good protection against some in- 

 sects. A handful of soot thrown over a melon vine, 

 or young cabbage plant, will keep away many in- 

 sects. 



Soot contains some ammonia, and as this is in 

 the form of a sulphate, it is not volatile, and eonse- 

 * See the glossary at the end of the book. 



