52 On the Cultivation of French Pears in Scotland, $c. 



fine earth, without such admixture of stony substances, is too re- 

 tentive of water during the winter months, which proves very 

 injurious to the fibrous roots of trees in our cold damp climate. 



Many opportunities of lifting the roots of trees, in borders dif- 

 ferently formed, have afforded illustrations of the foregoing facts ; 

 for those roots, raised from borders where the soil was mingled 

 with stones and rubbish, have presented a dense mass of fibrous 

 rootlets ; whilst others, which had grown in deep and rich borders 

 without such admixture of stony substances, have exhibited only 

 long naked roots, more or less destitute of fibrous appendages. In 

 the rubbish borders, the fibrous rootlets might be seen to seize, as 

 it were, on some substances of the soil in preference to others; 

 pieces of lime-plaster, or mortar, were generally preferred, being 

 often found enveloped in a mass of such rootlets ; next to these, 

 pieces of whinstone and brick were selected by the rootlets ; coarse 

 gritty sandstone they seemed to reject, but to like the fine white 

 sandstone which the roots of heaths are so fond of. 



In connection with this search after stony bodies, Mr. Drum- 

 mond mentions some curious facts respecting the directions which 

 roots take in borders formed, in part, of paving stones. If such 

 stones be laid at the bottom of the border with the view of pre- 

 venting the roots striking into the subsoil, the trees will soon send 

 down their roots until they come in contact with the pavement, 

 over the surface of which they will then spread themselves in every 

 direction. Should their extremities not be able to penetrate the 

 mortar or clay in which the stones are imbedded, they will, after a 

 time, push out beyond them, and then, dipping down, take an in- 

 verted position and extend beneath the pavement. On the other 

 hand, if the stones be laid on the surface of the border instead of 

 its bottom, the roots then seem to strike upwards, and spread along 

 the under surface of the stones. In both cases the stones seem to 

 attract and retain moisture, and, during the vegetating season, the 



