564 THE POPULAR SCIENCE MONTHLY 



I have already spoken of the sprouting capacity of the chestnut, and 

 for various reasons have stated that when coppicing is too long continued 

 it can only result harmfully. On the other hand, the sprout-produc- 

 ing ability per se should be reckoned as a distinct advantage to the spe- 

 cies. We know that when the Lumberman fells such trees as the pine or 

 hemlock he sounds the death knell of that individual. On the con- 

 trary, in the case of the chestnut, as we have seen, this is just the 

 operation which leads the way to an increase in the number of individ- 

 uals, for where one tree existed before, now four or five ultimately 

 develop, sprouting from the stump. This kind of "vegetative" repro- 

 duction which, eventually, of course, results in increased seed produc- 

 tion, is naturally an important factor in prolonging the life of the 

 species. Zon 18 says of the chestnut in southern Maryland : 



Were it not for its sprouting capacity and its frequent occurrences on slopes 

 difficult to till, chestnut in Maryland would be a species of the pa>-t. n- white oak 

 and several other species are fast becoming. 



There is, possibly, another point which may be in favor of the chest- 

 nut tree, although it applies only to the southern representatives of the 

 species. As far as we can judge from reports and surveys, the progress 

 of the chestnut bark disease into the southern states has been slow : at 

 least, it has apparently spread into this territory with no such rapidity 

 as has been remarked in the northern states. 



Under the circumstances, it is entirely reasonable to assume that 

 some condition exists in the south unfavorable to the development of the 

 blight fungus. Various explanations have been offered, but none of 

 them is more than a hypothesis, since, as far as I know, no accurate 

 scientific investigation of the case has been made. 



Perhaps the most plausible theory is to the effect that the southern 

 chestnut may contain a larger amount of tannin than the northern tree 

 and that this higher content of tannin may be inimical to a vigorous 

 development of the fungus. Whether it is actually a fact, however, that 

 a southern tree contains more tannin than a northern tree of equal age, 

 has not been determined. We know that the tannic acid manufacturers 

 use only southern chestnut for their material, and yet this may be 

 simply because larger trees exist in the south, and Ave know that the 

 older, larger trees contain more tannin. The actual comparat : ve tannin 

 content of northern and southern trees would form an interesting sub- 

 ject for future investigation. Dr. Clinton, 19 acting on the supposition 

 that some such relation as this might exist, has carried on some interest- 

 ing experiments with the chestnut blight fungus in culture media con- 

 taining various percentages of tannic acid. He has found, among other 



is Zon, loa. tit., p. 13. 



is Clinton, G. P., loc. tit., pp. 404-407, and pp. 430-434. 



