10 BULLETIN 765, U. S. DEPARTMENT OF AGRICULTURE. 



sick land and the adaptability of resistant Burley to it. The be- 

 havior of the resistant strains as compared with the ordinary Burleys 

 on the farm of Mr. William Feck is shown in figure 4. It does not 

 follow, nor is it recommended, that continuous culture of Burley 

 tobacco should be practiced in the Burley section. On small farms 

 or where suitable soil is scarce it may be highly desirable to grow 

 tobacco on the same land more frequently than hitherto has been 

 possible. The important point, however, is that the number of to- 

 bacco crops which may be grown on a given piece of land usually is 

 not sharply limited by lack of fertility, but rather by disease. The 

 value of resistant strains, therefore, lies in reducing the chances of 

 poor yields in second or third crops on soils gradually becoming sick. 



Fig. 4. — Resistant White Burley tobacco (on the right) and ordinary White Burley strains 

 (on the left) growing on the farm of William Feck, Lexington, Ky., in 1917. The 

 tobacco was about half grown when the photograph was taken. 



^Vith respect to the quality of the resistant Burley, considerable 

 evidence is at hand to show that so far as market value is concerned 

 it has not proved to be inferior to the ordinary strains. Some of the 

 growers who tried this seed in 1917 on a small scale planted as many 

 as 10 or 15 acres in 1918. The final reports as to the quality of the 

 1918 crop are not yet obtainable, but there is no reason to believe 

 that its average value will be less than that of ordinary Burley, i. e., 

 the Kelly, Halley, Big Stand-up, and other strains. 



RESISTANT BURLEY STRAINS RECOMMENDED FOR SICK SOILS 

 IN WHITE BURLEY DISTRICTS. 



Until stand-up Burleys of unquestionable perfection in quality are 

 obtained it is believed that growers can very profitably plant the re- 

 sistant drooping-leaved variety of Burle} T where it is desired to utilize 

 sick soils. It is recommended that those who are putting in second 



