4 BULLETIN 181^ XJ. S. DEPARTMENT OF AGKICULTUKE. 



Numerous creeks and ravines drain into the river; these vary in 

 size from streams with watersheds of 150 square miles to those 

 draining but one or two square miles. Figure 2 (in pocket at end of 

 bulletin) shows the location and extent of each of these tributaries. 

 Their channels, though smaller, are similar to that of the river. 



CLIMATE. 



The climate is typical of that of the Gulf States. Frequently 

 during the summer the temperature reaches 95° F. and maintains 

 that height for a considerable length of time. The winters are 

 usually mild, and it is very seldom that the temperatm-e fails to zero. 

 The records of the United States Weather Bm"eau at the Yazoo City 

 station show a maximum temperature of 107° and a minimum of 

 — 2°, with a mean annual temperature of 65°. 



The mean amiual precipitation during the past 12 years was 48.1 

 inches. The rainfall is well distributed throughout the year, the 

 least occurring during the cotton-picking season of September, 

 October, and November. A more extensive discussion of rainfall 

 will be found in the section of this report dealing with run-off (p. 7). 



AGRICULTURAL CONDITIONS. 



Throughout the Big Black bottoms the soil is very uniform in 

 character, being composed of a silty loam underlain by clay. The type 

 is called ''meadow" by the United States Bin-eau of Soils and is de- 

 scribed by the bureau as follows : ^ 



The surface few inches of the material composing the meadow consists of a brown 

 or drab silt loam. This is underlain by a drab, gray, or bluish silt or silty clay. In 

 local areas and especially near streams there is considerable sand present in both 

 soil and subsoil. * * * The type is still in process of foiTaation, each successive 

 flood bringing with it material that is left as a tliin deposit over the bottoms. The 

 soil is very rich, and if cleared, ditched, and diked would be capable of producing 

 large yields. At present it is of value only for its timber and the pasture it affords. 



The soil of the uplands is largely a brown or light brown loam, 

 underlain by a brown clay. It is considered fertile, but is very easily 

 eroded. 



The bottoms, which are at present unsuitable for tillage, were 

 originally covered with a heavy growth of timber consisting of water 

 oak, black and sweet gum, sycamore, beech, and some cypress. The 

 greater part of the valuable timber has been cut, and a second growth, 

 together with a heavy stand of cane, brush, and briars, now covers 

 the bottoms. With regard to lands bordering streams in Mississippi, 

 it is generally recognized that heavy growths of timber indicate 

 lasting productiveness of the soil, and that rank growths of under- 

 brush, cane, and vines, such as occur in these bottoms, are seldom 

 fomid on poor land. 



1 U. S. Dept. of Agr., Bureau of Soils, Sofl Survey of Holmes County, Miss., 1909. 



