THE CARE AXD MANAGEMENT OF THE DAIRY HERD. 4I 



The Maine soils coming from the disintegration of the rock in 

 place of from the grinding of the glacier, contain enough plant 

 food in themselves to last for a great many years. Luckily this 

 plant food is tied up so that the present generation cannot get it. 

 It is hard work to secure enough of it to supply the wants of a 

 growing crop, and it is quite impossible to get it in such excess as 

 to rapidly wear out the soil. The use of barnyard manure or 

 the plowing under of green crops aids the soil b}- furnishing 

 through decay, a large amount of carbonic acid gas, which unit- 

 ing with the water in the soil, gives an active acid which in turn 

 acts upon the insoluble phosphates making a small per cent of 

 them soluble in water and thus available to plants. 



The clover has one advantage over the timothy, its roots 

 furnish a larger gross amount of this decaying organic matter 

 than do the roots of timothy. On a certain occasion I took an 

 aliquot part of an acre in a clover field giving about i^ tons 

 of hay per acre, removed the crop to where the mower knives 

 would have cut off the plants, then washed out the soil to a good 

 depth, applying a stream of water under heavy pressure. The 

 roots in the upper 10 in. of soil were taken out, weighed and 

 analyzed. It surprised us greatly to find that they contained 

 as much plant food as would be supplied by at least ten loads of 

 barnyard manure per acre. Moreover, this plant food in the 

 case of the clover roots was disseminated through the soil, not 

 in layers as is done when barnyard manure is applied, but 

 scattered all through the soil, nicely mixed with the soil and 

 ready to decay during the hot months of July and August to 

 furnish plant food to the growing corn crop just when that crop 

 needs it most. There is nothing to be said against commer- 

 cial fertilizer. It is a good thing to use to supplement barn- 

 yard manure but it furnishes a great bulk of available plant food 

 when the crop is small and unable to utilize it, whereas the 

 decaying clover furnishes the plant food to the corn crop just 

 at the period of most rapid growth. Again, a large part of the 

 nitrogen stored up in these clover roots is obtained primarily 

 from the air by the bacteria working in the nodules on the roots. 

 By digging down four feet and examining the roots of the clover 

 at that depth, we found that they were engaged in bringing up 

 potash and phosphoric acid from the zone below the depth of 

 the roots of the cereals. \\'hatever plant food there was stored 



