ECONOMICAL TREES. 57 



conditions permitted to human experience. If, then, man shall 

 some day create living matter, he will be able to observe it during 

 a longer or shorter time ; he will be able to study it ; but it will 

 be an embryo, the development of which can not be completed, on 

 account of the absence of suitable conditions of the medium. — 

 Translated for The Popular Science Monthly from the Revue Scl- 

 ent ifique. 



ECONOMICAL TREES. 



Bt FREDERICK LE ROY SARGENT. 



THE well-known power which many plants possess of develop- 

 ing adventitious roots from almost any part, when placed 

 under favoring conditions, is manifested in a somewhat extraor- 

 dinary manner by several trees recently brought to the notice of 

 botanists. 



In the Bulletin of the Torrey Botanical Club for August, 1891, 

 the present writer published an account of a linden growing in 

 Boston, Mass., where it had been subjected to injury from horses 

 gnawing the bark, and in consequence had a considerable portion 

 of the trunk decayed, as shown in the accompanying sketch 

 (Fig. 1). At the edge of the wound the cambium had formed 

 a callus, and from a point in this living tissue there proceeded 

 several vigorous roots which penetrated the decaying wood in all 

 directions, evidently finding a rich soil. 



Subsequent issues of the Bulletin have contained descriptions 

 of several other examples of trees exhibiting a similarly economi- 

 cal utilization of the products of their own decay. These in- 

 clude swamp maples, a Norway maple, a willow, and a white 

 mulberry. In an English paper appeared not long ago an account 

 of an oak which had "sustained itself for years by a mass of 

 roots grown into its own trunk ! " 



In one of the swamp maples observed by L. M. Stabler, at 

 Great Neck, Long Island, the primary injury apparently resulted 

 from a storm which split and twisted the trunk. One of the ad- 

 ventitious roots, " at least two inches in diameter, started as high 

 as ten feet above the base of the trunk, and passed down through 

 the decayed portion to the ground " (Fig. 2). 



The Norway maple, described by W. A. Buckhout, had "a 

 large branch split off, showing that the splitting had started 

 several years before, that the margins of the trunk had become 

 well calloused, and from several points roots had extended into the 

 cleft, which naturally became partially filled with dust and decay- 

 ing bark. The largest root was an inch in diameter, divided con- 

 siderably near the lower end, and was over two feet long." 



