38 



BOARD OF AGRICULTURE. 



Question. Does the double Michigan plow throv?- the bot- 

 tom soil on top in pulverizing it ? 



Mr. Gould. That depends very much upon how it is 

 rigged. Ordinarily, that is the case. Two inches (which is 

 the best arrangement of the Michigan plow) of the surface 

 sods, grass, weeds, and everything, is turned bottom upwards 

 into the bottow of the furrow. A thorough mass of powder 

 is thrown up on top of them, so that it is completely inverted ; 

 that is, if the earth is somewhat damp. When the soil is in 

 a dry state, these circimistances are changed, and part of the 

 earth falls back into the furrow. 



Dr. Baljdwin. Is it considered desirable to turn the fur- 

 row flat ? 



Mr. Gould. We in New York do not approve of flat fur- 

 rows at all. The reason why I object to the flat furrow is 

 this : that it leaves no channel for the conveyance of water 

 underneath, which is a point very important to observe in 

 plowing the soil. It not only allows the water to come in, but 

 the air also. In order to convert the mineral matter in the 

 soil into food for plants, it is absolutely necessary to form car- 

 bonic acid in the soil, and also another kind of vegetable acid, 

 which is known to chemists as humic acid. These two acids 

 can only be formed in consequence of the presence of the 

 atmosphere in the soil. If the atmosphere is excluded these 

 two substances cannot exist there. The humic and carbonic 

 acid are the two substances which dissolve the mineral mat- 

 ters in the soil and place them in such a condition that they 

 can be absorbed by plants. Now, when the furrows are turned 

 so as to lap over, upon one another, a channel is left on 

 the under side, which allows the water to drain off, and per- 

 mits the air to enter, which generates these two acids. 



Dr. Baldwin. Where would you put the manure in those 

 furrows ? 



Mr. Gould. I should let the manure go where it wanted 

 to. My impression is, if you are going to plant corn, for in- 

 stance, and put on green manure, the best way is to spread it 

 on top and plow it under. If the manure were thoroughly 

 rotted, I should want to put it nearer the top. 



