CONSERVATION PRACTICES FOR TOBACCO LANDS 



39 



Table 8. — Tobacco yield, price per pound, and per-acre value as affected 

 by early and late turning of various cover crops, Beltsville, Md., 19^6 



Covers 



Yield per acre 



Price per pound 



Value per acre 



Early l 



Late 2 



Early 



Late 



Early 



Late 



None 



Pounds 

 1, 273 



Pounds 

 1, 132 



Cents 

 41. 3 



Cents 

 38.4 



Dollars 

 511 



Dollars 

 432 







Nonlegumes: 



Wheat . 



1, 415 

 1,300 

 1, 253 



1, 251 

 1,398 

 1, 146 



42. 8 

 45. 1 

 40. 1 



46. 3 

 42. 1 

 41. 



608 



587 

 503 



581 



Rye 



586 



Ryegrass '. _ 



480 







Average 



1, 322 



1,265 



42. 7 



43. 1 



566 



549 



Vetch 



2,018 



2,224 



40. 2 



37.2 



805 



828 







Mixtures : 



Wheat-vetch 



Rye-vetch 



Ryegrass-vetch 



1, 728 

 1,905 

 1, 751 



1,828 

 2,094 



2, 296 



47. 3 

 44. 7 

 44. 3 



45.4 

 42. 3 

 44. 4 



820* 

 855 



774 



825 



885 



1,022 



Average 



1,795 



2, 072 



45. 4 



44.0 



816 



910 



Grand average- _ 



1,580 



1,671 



43. 2 



42. 1 



683 



705 



1 Turned Apr. 11. 



2 Turned May 17. 



1. During the period 1940 to 1946 where the land was protected 

 over winter by a cover crop of wmeat and vetch, and during the sum- 

 mer by a 1-percent grade ridged row, seven successive tobacco crops 

 were grown without evidence of decrease in either yield or value of 

 the crop. The land used in this experiment had remained in natural 

 sod for at least 6 years before it was first plowed for tobacco. This 

 suggests that where good erosion control is practiced, land plowed out 

 of sod may be used to grow several successive tobacco crops without 

 causing decrease in crop value. 



2. The detailed studies on winter cover crops carried out in 1946 

 indicate that better crop returns may be expected when the winter 

 cover contains vetch in mixture with wheat, rye, or ryegrass than when 

 vetch or any one of the nonlegumes is used alone. In all cases except 

 ryegrass alone the use of winter covers gave substantial increases in 

 the tobacco crop returns. Late turning of the cover crops containing 

 vetch gave much the highest tobacco returns followed in order by 

 early turning and late turning of the nonlegumes without vetch. The 

 early-turned residues quickly disappeared, whereas in case of late 

 turning a considerable amount of the nonlegume crowns and stems were 

 still visible in and on the soil at tobacco harvest time. Since the effect 

 of crop residues in decreasing erosion is known to be increased with 

 their resistance to rapid decomposition these studies suggest late turn- 

 ing of the vetch-nonlegume covers as a means for increasing both crop 

 value and erosion control. 



