246 SEEDING AND PLANTING 



hand from a near-by well or other source from time to time as 

 required. 



17. Distribution of Water. The arrangement for the dis- 

 tribution of the water is of considerable importance. It is usually 

 broughtjrom the reservoir to the beds in a series of iron pipes 

 which are laid on the surface or at some distance below. When on 

 the surface, the pipes are relocated each season and taken apart and 

 stored over winter and during the spring when the ground is 

 worked. This method of distribution is practiced in many of the 

 forest nurseries in the United States. The main pipes should be 

 at least two inches in diameter in large nurseries in order to permit 

 a rapid distribution of water. The main pipes are laid along the 

 main roads and the smaller ones along the lateral roads and paths 

 at either side. Hydrants are located at convenient points. 



There is considerable advantage in the distribution of water 

 through pipes laid temporarily on the surface, as they can be 

 shifted from one part of the nursery to another, depending upon 

 the particular place where the seedbeds are located. Water is 

 usually artificially applied only to the seedbeds, which may occupy 

 one-tenth or less of the entire nursery. When the pipes are laid 

 underground, all parts of the nursery should be piped so that the 

 seedbeds can be located, if need be, in any part. Underground 

 pipes should be below the frost line or else the water should be 

 drawn off during cold weather. Where the water is drawn off 

 during freezing weather, the pipes need be only sufficiently deep 

 to escape the plow in working the soil. 



Water is distributed to the beds in one of the following four 

 ways : 



a. Sprinkling. 



b. Flooding. 



c. Percolation from furrows. 



d. Sub-irrigation. 



18. SPRINKLING. The distribution of water over the beds as 

 a finely divided spray is admirable, as it is the nearest approach to 

 rain. It should be uniformly distributed at a rate sufficiently slow 

 to permit its complete absorption by the soil. The application should 

 be sufficiently prolonged to wet the soil thoroughly to a foot or 

 more in depth. Light sprinkling at frequent intervals, which 

 only moistens the soil to a depth of 1 to 3 inches, is not as 

 effective as a prolonged application at infrequent intervals. 



