38 



MISC. PUBLICATION 6, 



U. S. DEPT. OF AGRICULTURE 



Table 7. — Average yield, price and value of tobacco following no 

 winter cover compared to tobacco following fertilized and unfertil- 

 ized winter covers. (All tobacco grown on ly^-percent grade ridge 

 rows, Raleigh, N. C, 1942-47.) 



Treatment 



Yield per 

 acre 



Price per 

 pound 



Orop value 

 per acre 



No cover, ___ 



Pounds 

 1,062 

 1,060 

 1, 166 

 1, 120 

 1,057 



Cents 



45 

 45 

 43 

 45 

 46 



Dollars 



477 



Rye _ _ 



473 



Rve and nitrate 



504 



Ryegrass. _ __ 



504 



Ryegrass and nitrate 



486 







The soil was naturally low in organic matter. To increase the amount 

 of organic amendment, and to secure maximum erosion control, the 

 cover crop was permitted to grow until the wheat reached the early 

 bloom stage. This cover-crop residue was resistant to quick decompo- 

 sition as evidenced by the wheat crowns and stems that were abundant 

 in and on the soil at tobacco harvest time. Tobacco yields and values 

 under this method of handling the cover crop have been good. 



Since this method of cover-cropping is not commonly practiced by 

 farmers, a supplemental experiment was carried out to compare early 

 and late-season turning of winter covers. The early turning was done 

 on April 11 when the covers were in a succulent green-manure stage. 

 Late turning was done on May IT when the nonlegumes were well- 

 stemmed and beginning to bloom. The covers tested were wheat, rye, 

 ryegrass and hairy vetch and each of the three nonlegumes in mixture 

 with vetch. Two replications were used except in case of the check 

 plot. The land treatment began with the fall seeding of cover crops. 

 Two cover crops and one crop of tobacco were grown in preparation 

 for the experiment. The cover crops were seeded during the last half 

 of September in each year. Seeding rates were : Vetch, 40 pounds ; 

 rye and wheat, 5 pecks ; and ryegrass, 4 pecks per acre. The test crop 

 of tobacco in 1946 was planted June 4 and harvested from August 21 

 to September 10 as the crops on the various treatments matured. 

 Results of this experiment are shown in table 8. 



Statistical analysis of the data presented in table 8 showed sig- 

 nificant differences due to treatments as follows: (1) the vetch alone 

 and in mixtures increased the tobacco yield and total crop value. (2) 

 Late turning increased yield where vetch was contained in the cover 

 crop and decreased yield when vetch was not in the cover crop. 



(3) The nonlegumes (wheat-rye-ryegrass) with or without vetch in- 

 creased the tobacco price per pound over the check and vetch alone. 



(4) Ryegrass alone, and land with no cover, gave lower crop value 

 than that with wheat or rye alone. 



Practical results of the studies at Beltsville on winter cover crops 

 and their application to erosion control for Maryland tobacco land 

 may be summarized as follows : 



