480 TOBACCO PRODUCTION 



Shed Burn or Pole Rot. Shed burn or pole rot occurs in the 

 house. Sometimes it never develops beyond small dark spots on the 

 curing leaf, and in other cases it may involve the entire leaf and 

 may in extreme cases destroy the house of tobacco. 



It is controlled by the proper regulation of temperature and 

 humidity of the air. It does not develop below 60 F. nor in air 

 where the humidity is below 8 ! 5 F. As the temperature is raised 

 the humidity must be kept at the proper stage or loss will follow. 

 This is often difficult in air curing. 



Stem Rot. Stem rot is a fungous disease that attacks the stem 

 in the house. It is controlled by regulating heat and moisture. 



Wet Butts or Fat Stern. This disease is characterized by wet, 

 discolored and soggy condition of the stem during curing. It may 

 extend to the leaf veins. Late tobacco is more likely to be attacked. 

 Open fires to dry the air will usually check the trou'ble. 



Black Rot in Sweating. Black rot in sweating is recognized 

 by dark brown or black color instead of the normal color of the cured 

 leaf. It loses texture and develops its own peculiar odor that is 

 detected by any tobacco man. It grows best in a temperature of 

 about 100. To avoid trouble the tobacco should be cured out before 

 freezing weather. Forced sweating that raises the temperature to 

 113 will prevent black rot. If the moisture is low enough the 

 disease will not develop. 



White Vein Disease. In this disease the veins assume a 

 whitened appearance. It occurs in drying weather. It may be pre- 

 vented by sprinkling water on the floor to keep up the humidity of 

 the air. 



Molds or Rusts. White molds or mustiness occurs to some 

 extent on fermenting tobacco. It may be controlled by the methods 

 suggested under black rot in sweating. 



LABORATORY EXERCISES 



1. Examine tobacco soils in laboratory. 



2. Separate large and small tobacco seed. 



3. Study types of cured leaf. 



4. Examine and use spraying machines. 



5. Make a mixture of arsenate of lead and ashes for poisoning horn 

 worms. 



FIELD STUDIES 



1. Study tobacco soils in neighborhood. 



2. Study growing tobacco plants. 



3. Visit tobacco plant beds. 



