FOR BETTER CROPS W THE SOUTH 



93 



The simplest system is indicated in Figure 1. There is a main 

 line with laterals wherever occasion requires. This system may 

 be used in small fields, and on small undrained areas. 



The grouping system, as shown in Figure 2, is a combination 

 of several natural or simple systems, and may be used where the 

 area is quite large, in basins, sloughs, and elsewhere if a good 

 outlet is available. By a natural system is meant one that fol- 

 lows the direction that the water takes when running off the 

 surface. 



The gridiron system, as shown in Figure 3, is sometimes 

 adapted to land that is nearly level, and is made up of a series 



>o 



CO 



<M 



'*** 



*Fig. 3. The gridiron system 



of parallel laterals,each emptying into the same main line. 



Each of these systems embodies the use of the four principles 

 as outlined above; namely, following the natural lines of drain- 

 age, avoiding the use of short laterals, following straight lines, 

 and reaching all parts of the field. 



Depth of Tile — The depth at which tile should be laid varies 

 considerably in different soils. In the prairie land of some 

 sections subject 'to periodical freezing, and where the soil is of 

 an alluvial nature, the tile line may be laid four to four and a 

 half feet, and yet give good results. In soils that are- waxy, 

 impervious, and of a fine texture — of a buck shot nature — the 

 tile should not be laid so deep. Generally speaking, the best 

 success has been obtained in most Southern soils by laying the 



