98 TOBACCO LEAF. 



crop is in little danger after a period varying from ten 

 to twenty days after the beginning of curing. The rem- 

 edy suggested is free ventilation and control of tempera- 

 ture by aid of artificial heat. 



Behrens,* in a similar study, found instead of a 

 Cladosporium, Botrytis cinerea P. , a spore-bearing fun- 

 gus, and Sclerotinia Liber tiana, Fckl., acting as the 

 forerunners of decay, while others f have noted Pleo- 

 spora sp., Botrytis vulgaris, Fr., and two species of the 

 genus Muwr as thus active. 



Another disease to which curing tobacco is also sub- 

 ject, is " stem rot," or white vein. This often attacks the 

 stalk a few days after cutting, but sometimes appears, 

 late in the curing, upon imperfectly dried ribs and veins. 

 These parts of the leaf are covered with patches of a 

 long-piled, velvety mold of pure white color. Later, 

 the web of the leaf is often invaded. These white 

 patches are the mycelium of a species belonging to the 

 genus Botrytis; the threads of the mycelium, first at- 

 tacking the surface, later penetrate deeply into the un- 

 derlying tissues. From the mycelial threads spring erect 

 fibers, one-fourth of an inch high, giving the velvety 

 appearance. These erect stems bear branches, extend- 

 ing at right angles, and at the tips of these branches are 

 formed the reproducing spores. This advanced state of 

 development is rarely reached on the curing tobacco, be- 

 cause the time is too short and the moisture insufficient. 

 The formation of spores occurs in the stems and ribs 

 after the stripping, and often the fungus springs up 

 over the floor of the curing barn, and the next crop of 

 leaf hung in the building will be in danger of inocula- 

 tion by means of the spores developed by this growth of 

 the fungus. The remedies suggested by SturgisJ are 



Zeitschrift fUr Pflanzenkranklieiten, 3, p. 82. 



t Sturgis, Report of the Connecticut Agricultural Experiment Sta- 

 tion, 1893. p. 85. 



t Report of the Connecticut Agricultural Ex. Sta., 1891, p. 185. 



