SUB-IRRIGATION 67 



abandoned. All experiments proceeded upon the plan of thus 

 making permanent water conduits below the point reached in spad- 

 ing or plowing, and they all became inoperative. The failure was 

 usually charged to the filling of the pipes with plant roots and in 

 some cases this was seen to be the reason. In other cases the failure 

 of the system was due to the fact that in light soils lacking capil- 

 larity, the water rapidly sank away from the pipes out of the reach 

 of the roots and shallow rooting plants failed though there was 

 moisture flowing to waste through a pervious subsoil. Mr. E. M. 

 Hamilton of East Los Angeles invented a system of continuous 

 cement pipes laid by a machine operating in the trench which pre- 

 vented access of roots because it had openings only at intervals 

 where the water was discharged into air spaces each of which could 

 be seen through a vertical pipe rising to the surface and furnished 

 with a cover. This has worked well for many years on Mr. Hamil- 

 ton's place for the irrigation of trees or other deep rooting plants 

 at considerable distances apart, for which use it seems-best suited. 

 To fill the earth with such pipes with openings near enough together 

 to serve for shallow rooting vegetables, is appallingly expensive, 

 and the stand pipes cumber the surface so that nothing but hantl 

 spading or cultivating could be done without destruction of them. 

 It would be cheaper and better to pipe the ground with iron pipes 

 and brass faucets even though the theoretical advantage of subter- 

 ranean application had be be abandoned. 



At the east within a few years the use of the drain tile laid 

 along the rows of vegetables near the surface has given the best 

 results in an experimental way. By this plan the tile are to be taken 

 up and relaid for each crop, which can be quickly done. Water 

 thus administered may serve well in soil not disposed to puddle 

 down or possibly may be more successful where the summer air is 

 less dry and soil baking less active than in California, but in many 

 of our garden soils the soil would solidify, and even if moisture 

 were adequate to prevent baking, the proper entrance of air would 

 be largely prevented. On the other hand, in coarse soils water 

 applied underground would quickly pass out of reach of shallow 

 rooting plants. 



The experience of Californians is against any such arrange- 

 ment of soil and water. Except in such soils as have already been 

 described as working well by seepage systems, surface application 

 of water followed by thorough surface cultivation, produces as a 



