404 CONNECTICUT EXPERIMENT STATION REPORT, IQI2. 



as compared with plants grown in Peru. Yet when plants from 

 England were sent to India, their vigor was restored, and an 

 increase of the alkaloids was shown by chemical analysis, 

 especially in the descendants of plants sent there. 



McKenney (Science 31, p. 750) writes concerning the blight 

 of Central American bananas: "The juice of diseased plants 

 contains much less tannin than that of the normal plants. * * * 

 It has been proved that the disease is not due to local conditions, 

 such as too wet or too dr> soil, etc. Yet some of these con- 

 ditions may predispose the plants to the disease." He does 

 not say whether the lessened tannic acid is the result of the 

 disease or vice versa. 



Tannic Acid and its Relationship to Chestnut Blight. The 

 chestnut as a source of tannin is one of our most important 

 trees. However, it seems that most of this tannin is made 

 from the chestnuts in the South, although they are utilized as 

 far north as Pennsylvania. The reason for this is that the 

 chestnuts in the South furnish a greater percentage of tannin 

 than those in the North. At least one cause for this seems to 

 be that the older the trees the greater the percentage of tannic 

 acid, since the tannin is made from the ground wood and 

 apparently comes largely from the older wood. As a rule, the 

 chestnuts of the South are much older than those of the North, 

 and are more likely to be seedlings. As yet the chestnut blight 

 has not caused much harm in the South. Whether or not the 

 present of more tannic acid in the trees there has any rela- 

 tionship to the absence of the blight is as yet uncertain, but 

 there is a possibility of its having a direct bearing. 



In answer to a question regarding variation of tannic acid 

 in chestnut trees, Mr. F. Veitch, of the Leather and Paper 

 Laboratory of the United States Department of Agriculture, 

 writes me as follows: "I have your letter of the nth inst. 

 asking for the tannin content of chestnut wood. This differs 

 all the way from 2 per cent, to as high as 10 or 12 per cent, in 

 very old, dry chestnut. The chestnut wood used by extract 

 makers probably averages around 6 per cent, of tannin. I can 

 make no more definite statement regarding the tannin content 

 of any particular chestnut than to say that young chestnut as 

 a rule contains the least, while the old chestnut contains the 

 highest percentage of tannin. Only the body and large limbs 



