RECLAMATION OF LOUISIANA WET PRAIEIE LANDS. 437 



Ordinarily, the lateral ditches in heavy soils are placed 100 feet 

 apart and are dug some 3 feet deep, with bottom width of about 2 feet 

 and a top width of about 4 feet. Formerly these laterals were dug 

 entirely by hand, but a ditcher machine has been developed which 

 now digs them with great rajiidity as well as economy. A view of this 

 machine may be seen in Plate XIX. All the larger ditches are con- 

 structed usually by floating dipper dredges having 1 or H yard dippers, 

 and the present contract price is about 7 cents per cubic yard." 



Thus far drain tile has not been extensively used in this locality, 

 as the nature of the soil and the slopes found are likely to introduce 

 difliculties which will have to be overcome before underdrainage is 

 universally adopted. It is probable that in the coarser, looser soils 

 near the bayous and streams tile would be more effective than in 

 the more impervious silt farther out in the swamps. If it can be 

 successfully introduced so as to supersede in part the use of the smaller 

 ditches, a gain in land area and in convenience of cultivation and in 

 the effective draining and aeration of the soil would be the result. By 

 proper care in protecting the joints, it is improbable that silting of the 

 tile would give much trouble. 



As a general thing, the water table of the plantations in southern 

 Louisiana is carried at from 1^ to 3 feet beneath the surface, and it is 

 well known that the greater depth is preferable, as, besides furnishing 

 a greater depth for the roots of the growing crop, it also furnishes 

 greater reservoir capacity in the soil to provide against excessive 

 rainfall. It likewise makes possible a smaller pumping equipment. 

 By keeping the pumps running during the winter season, when neces- 

 sary, the water table is kept as low as possible, aeration of the soil 

 takes place, and the soil is thus put in good physical condition. 



PUMPING PLANTS. 



Some plantations are so situated that fairly satisfactory drainage 

 can be secured by the installation of outlet gates through the levees, 

 cither automatic or hand regulated. These drain the system of 

 reservoirs and ditches in times of sufficiently low water, but when the 

 water outside the levees is higher than the outlet, of course the gates 

 must be closed and the reservoirs depended upon to hold all the inte- 

 rior drainage water. A great majority, however, of the plantations 

 which are reclaimed require the installation of a pumi)ing ])lant in 

 order to make the drainage system effective at all times and make the 

 leveed area in(lej)endent, with the possible excei)ti()n of seepage, of 

 everything except the rainfall. These pumping e(|uipments vary 

 greatly according to individual opinions and means, but each partic- 

 ular location should be studied carefully in connection with all its 

 surrounding conditions in onler to choose an installation whose first 



aU. S. Dept. Agr., Office Expt. Stas. Circ. 74. 



