No. 63. J 73 



will trample down more, and this, mixed witii their dung, forms 

 in its decay a most efficient top dressing; and repeated for two or 

 three years, forms an admirable preparation of the soil for wheat or 

 other grains. When a crop is cultivated to be plowed in, it should 

 be done at the time when the plants contain the greatest quantity of 

 nutritive matter, and have least exhausted the soil in which they are 

 growing. This, in most cases, will be when the plants have come 

 fully into flower. At an earlier period there may be as much weight, 

 but a larger portion of it will be mere water; and, if allowed to stand 

 much later, the soluble matter is lost in the seed, and the ligneous 

 part of the stem becomes more difficult of decomposition. Buck- 

 wheat is a good plant for a green manure; its growth is rapid, and 

 gives a great weight per acre, and two crops may be plowed under in 

 a year. The best way of plowing in such green crops, is to pass a 

 heavy roller over them, which lays the plants close to the ground, 

 and greatly facilitates covering them by the plow. It is believed that 

 corn, sown broad cast, and when just showing its tassels, cut and co- 

 vered by the plow, would be one of the best crops that could be cho- 

 sen for this purpose. A man or boy, in this case, would be required 

 to follow the plow, to place the corn in the furrow for covering, at 

 the next passage of the plow. Taken at this time, corn abounds in 

 nutritive matter, and could scarcely fail of proving a first rate fertili- 

 zer of the soil. 



A variety of decomposed vegetable matters, or those partially de- 

 composed, are used as manures. The fallen leaves of trees are of 

 p this class; but the instances are few in which they will repay 

 the expense of gathering; perhaps never, in the United States, 

 where the other sources of an abundant supply of manures are so nu- 

 merous. If collected, the best method of using them, is to litter sta- 

 bles, or form beds for pigs, or mix at once with other manures; as, in 

 such ways, they absorb urine and other fluids that might escape, and 

 together undergo decomposition. But the most important source of 

 decayed vegetable matter, and one, the value of which is not yet by 

 any means sufficiently understood or appreciated, is to be found in 

 the great tleposits of this substance in swamps, low meadows, and 

 peat bogs, in all parts of our country. On the subject of this kind 

 of manure, there is no authority equal to Dr. Dana of Lowell, Mass. 

 According to him, peat consists of soluble or insoluble geine or hu- 

 mus, with a few salts. From an analysis of ten specimens from dif 



[Senate No. 63.] K 



