Page:Popular Science Monthly Volume 84.djvu/561

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FUTURE OF THE CHESTNUT TREE
557

more, vigorous trunks remain, which on reaching a suitable size are cut down and used for railroad ties, telegraph poles, or lumber, as desired; and from their stumps new coppice shoots arise, to repeat the whole history of their forebears. In some regions this coppicing has gone on for four or five generations of sprouts.

The question now before us is, "Does this continued coppicing weaken the vitality of the chestnut tree and thus make it more susceptible to disease?" The general opinion seems to be in the affirmative. Zon,[1] speaking of the chestnut in southern Maryland says:

It must not be forgotten, however, that a chestnut stump can not go on coppicing forever. With each new generation of sprouts, the stump becomes more and more weakened, and hence gradually loses its capacity to produce healthy and vigorous sprouts. Although it is impossible to state with certainty how many generations of chestnut can be raised from the same stock without impairing the vitality of the sprouts, the effects of repeated and bad coppicing manifest themselves in the increasing number of dying chestnuts all over Maryland. The immediate cause of their death can nearly always be traced to attacks of either insects or fungi, yet the prime reason is their decreased vitality, which makes them easy prey to their natural enemies.

As stated by Dr. Clinton:[2]

It is certainly a curious coincidence that the blight makes its first appearance and causes its greatest damage in the regions where the chestnut has suffered most from repeated cutting over.

Dr. Clinton quotes Nellis, of the U. S. Forest Service, who, in an unpublished working plan on "Utilization of Blight-killed Chestnut," writes:

It is expected that this study will show that the present range of the chestnut bark disease is in a region of entirely second growth chestnut, which has been culled of its most valuable timber, where only rough products are now being produced.

Without entering into the discussion as to the relation of the bark disease to coppiced areas, I will merely state that coppiced chestnut is in general apt to be affected with disease of some sort. Especially frequent are heart-rotting fungi which may enter by way of the decaying parent stump, and the unsound condition of the trunk they cause is communicated to succeeding generations. It is also conceivable that the root system of the sprouts, inasmuch as it is partly that of the parent tree, may be weaker on this account. For, although we have no evidence to prove that the parent root system becomes inherently weaker with age, yet it is reasonable to expect that the soil about it would become more and more exhausted of its nourishment, to say nothing of possible external injuries to which it might be subjected in the course of a long period of time.

As already intimated, forest fires are extremely disastrous to the

  1. Zon, R., "Chestnut in Southern Maryland," Bureau of Forestry, U. S. Dept. of Agric. Bull., 53: 29, 1904.
  2. Clinton, G. P., loc. cit., p. 402.