174 THE CULTURE OF FARM CROPS. 



the river bottoms which are periodically overflowed, but 

 which are torn up and w r ashed by the floods instead of being 

 fed and enriched. 



The mode of procedure is as follows. A dam is made 

 across the stream in the most convenient situation, and the 

 water is carried out on one side in a ditch, as if for the pur- 

 pose of running a mill. When the ditch attains a sufficient 

 elevation to cover the desired space of ground, the water is 

 let out through gates and small channels on to the land. 

 The land is previously leveled and made smooth by repeated 

 plowing and scraping, until an even surface has been formed. 

 It is then sown with the kinds of grasses best suited to this 

 mode of cultivation; but any of the best varieties, as timo- 

 thy; perennial rye grass; orchard grass; meadow fescue; red 

 top; meadow oat grass; fowl meadow grass; may be grown 

 under this system. As the land will slope a little towards 

 the river bank, the space between this and the ditch will be 

 best laid out into broad terraces, enclosed with low dams, 

 by which the water is retained over the smooth level sur- 

 face at a depth of 3 inches, or thereabouts, in each division, 

 whenever the grass needs the water. This may be weekly, 

 in the growing season, and the water may be turned on for 

 one night in every week, to soak the ground thoroughly, and 

 prevent it from drying so as to stop the growth of the grass. 

 There ^s no danger of injury to the ground, because the 

 gates are made to discharge into ditches which gradually 

 overflow until the whole surface is covered. When this is 

 effected, the surplus water flows off through gates on the 

 border of the river; and through the lower dam or bank. 

 Thus a continuous sheet of water is left flowing over, or 

 through the grass, carrying the most luxuriant vigor to the 

 crop, and stimulating the growth enormously. The more 

 water that passes over the grass, the more of the most val- 

 uable plant food is brought within reach of the roots. Ev- 

 ery blade of grass acts as a filter which retains matter that 

 may be in solution, or is carried in suspension in the water 

 which slowly passes over the ground. Any solid matter that 

 may be carried in the water is thus deposited on the land, 



