FUTURE OF THE CHESTNUT TREE 5&5 



things, that while the fungus grew vigorously up to a certain percentage 

 of tannic acid, its development was very sensibly retarded if the percent- 

 age was slightly increased beyond this point. If the southern tree actu- 

 ally contains a large amount of tannin we should have here a funda- 

 mental barrier to the advance of the chestnut blight fungus, and thus a 

 decided advantage in favor of the southern representatives of the species. 

 However, as I have already intimated, the whole matter is theoretical, 

 since there is entirely insufficient evidence to substantiate it. 



If we summarize, then, the points which the American chestnut has 

 to its credit on the asset side of the balance sheet, we find that it exhibits 

 a rapid and vigorous growth, it is fairly tolerant, at least in youth, it is 

 not over particular as regards soil requirements, it enjoys longevity as 

 an inherent characteristic, it reproduces itself by sprouting from the 

 stump, and finally, as regards the trees in the southern section of its 

 range, their supposedly larger content of tannin may prove to be a pro- 

 tective power against the annihilating advances of the bark disease. 



This list is impressive — in fact, one could hardly conceive how the 

 species could be more favored, and, indeed, these are undoubtedly the 

 main reasons why it has been so firmly established and abundant 

 throughout its range. 



"When we review the troubles by which it is assailed on every hand, 

 it is remarkable how many of them are due primarily to man's activities : 

 as, for example, the introduction of the bark disease, continued forest 

 fires, repeated coppicing, change of soil conditions from cutting over 

 large areas, etc. And although through the efforts of a few some of the 

 evils may be checked or diminished, from .the complex nature of the case, 

 the deadly work will inevitably continue. One can not avoid the convic- 

 tion, therefore, that, if the present conditions persist, the virtual extinc- 

 tion of the American chestnut is only a question of time. In the south 

 it is dying out where it once flourished, and in the north its general con- 

 dition is such that it may soon cease to be classed as an important timber 

 tree. How long it will survive it is of course impossible to predict with 

 any degree of exactness. But at the present rate of decline its future life 

 may possibly be measured in hundreds of years, but not in thousands. 



The most hopeful indications for chestnut in North America in the 

 future lie along the line of breeding experiments. Since the blight is out* 

 worst enemy, work on the development of varieties immune to this is of 

 the highest value. It has long been known that certain Japanese forms 

 are somewhat resistant to the blight, and the disease is comparatively in- 

 conspicuous on the Chinese chestnut, on which it has recently been 

 found. 20 Fortunately work on hybridization of chestnut species had been 

 started long before the blight was discovered in this country. Among 

 20 Metcalf , Haven, loc. cit. 



