10 BULLETIN 71, U. S. DEPARTMENT OF AGRICULTURE. 



face of the Sharkey clay to a depth of from 1 foot to more than 3 feet. This 

 more or less decomposed mass is made up of the trunks and leaves of trees, 

 but more largely of the rank weeds and grasses which flourish in this locality. 

 The extensive tracts covered by the muck are poorly drained and almost 

 impenetrable. The only places where this type can be seen under any favorable 

 conditions of drainage are between the drainage canals which lead from New 

 Orleans to Lake Pontchartrain. Clearings have been made and it has been 

 demonstrated that the muck can be reclaimed, but so far none of it has been 

 cultivated. The muck in many of the localities in which it was observed is 

 finely divided and well decomposed and should be well adapted to the cultivation 

 of those crops which thrive on the peaty soils. 



Of the type called Galveston clay the Bureau of Soils says : 1 



The Galveston clay consists of a mucky mass of vegetation in various stages 

 of decay, interspersed with a fine clay of drab color. Along the borders of the 

 marshy prairies covered by this type the soil closely approaches in texture 

 the Sharkey clay, and passes into a subsoil similar to that of the Sharkey clay 

 at lower depths, but the lower lying strips nearer the bayous are little more 

 than peat bogs to a depth of more than 3 feet. 



The Galveston clay forms a broad border along the Bayous des Allemands, 

 opening out a short distance above the town of Des Allemands to a width of 

 several miles outside of the present area, with an arm extending northward 

 toward the town of Hahnville. The latter extension follows the course of a 

 sluggish bayou with its many ramifications through the marsh. 



The topography of the type is that of a low marsh but little elevated above 

 sea level. Water stands over much of the surface at all times in pools and 

 channels and renders the marsh almost impenetrable except by boat. * * * 

 The areas occupied by this type are entirely treeless and devoid of other vege- 

 tation, except sparse marsh grasses which have little value for grazing. This 

 absence of vegetation, in such contrast to the dense swamp growth on the 

 Sharkey clay, is due largely to the brackish nature of the water which ascends 

 the bayous at high tide, and perhaps in part to the peaty nature of the soil, 

 with its poor drainage. 



From the foregoing it will be seen that the type called Galveston clay is a 

 combination of the so-called Sharkey clay with muck, with the former as a 

 subsoil. Over the whole of the wet prairie section of the Delta this type of soil 

 is found, the muck varying in thickness from a few inches to several feet. The 

 tracts of land that are now being reclaimed in southern Louisiana all contain 

 more or less of this muck land, and many of the districts are entirely covered 

 by it. 



DRAINAGE CHARACTERISTICS OF SOILS. 



As the ultimate success of most of the reclamation districts of this section 

 will depend on the successful drainage and cultivation of these muck lands, a 

 rather detailed study of them was made. In investigating these soils it was 

 the endeavor to get a careful description of their physical characteristics, to find 

 the percentage of water by volume that they would contain when in good condi- 

 tion for growing crops, and to ascertain the amount of water they would hold 

 when completely saturated. 



The muck is a mass of vegetation in varying stages of decay and contains 

 varying amounts of river silt. In character it differs according to the kind of 

 vegetation from which it was derived; thus the muck of the cypress swamp is 

 much darker and less fibrous than the muck or turf of the open grass-covered 

 prairie. Also, according to stage of decay, it may be tough and fibrous and able 

 to bear the weight of a man, or it may be soft and even semifluid if consid- 

 erable water be present. Being the result of growth rather than of deposit, 

 it has been formed in layers, the depth of which depends largely on the time 

 involved. When a layer of vegetation is covered with a heavy layer of silt all 



HJ, S. Dept. Agr., Field Operations of the Bureau of Soils, 1903, p. 453. 



