PRUNE ROOTS BEFORE PLANTING. 461 



this fluid, and often becomes the seat of disease which spreads 

 to parts that would otherwise be healthy. To this it may be 

 added that decaying roots become the seat of dry-rot fungi, 

 which, once established, rapidly introduce their spawn among 

 the living tissues, and produce diseases which only end in 

 death. 



When, however, the wound is made clean by a skilful pruner 

 the vessels contract, and prevent the introduction of an excess 

 of water into the interior; the wound heals by granulations 

 formed by the living tissue, and the readiness with which this 

 takes place is in proportion to the smallness of the wound. It 

 may be sometimes advantageous to remove large parts of the 

 coarser roots of a tree, even if they are not accidentally wounded 

 when taken up, the object being to compel the plant to throw out, 

 in room of those comparatively inactive subterranean limbs, 

 a supply of young active fibres. TMs is a common practice 

 in the nurseries when transplanting young Oaks and other 

 tap-rooted trees, and is one of the means employed by the 

 Lancashire growers of Gooseberries, in order to increase the 

 vigour of their bushes ; in th.e last case, however, the operation 

 is not confined to tbe time when transplantation takes place, 

 but is practised annually upon digging tbe Gooseberry borders. 

 The reason why cutting off portions of tbe principal roots 

 causes a production of fibres appears to be this : the roots are 

 produced by organizable matter sent downwards from the stem ; 

 that matter, if uninterrupted, will flow along the main branches 

 of the root, until it reaches the extremities, adding largely to 

 the wood and horizontal growth of the root, but increasing, in 

 a very slight degree, the absorbent powers ; but if a large limb 

 of the roots is amputated, the powers of the stem remaining 

 the same, all that descending organizable matter which would 

 have been expended in adding to the thickness of the ampu- 

 tated part is arrested at the hne of amputation ; and, unable to 

 pass further on, rapidly produces granulations to heal the 

 wound, immediately after which young spongioles appear, soon 

 establish themselves in the surrounding soil, and become the 

 points of new and active fibres. 



By many excellent planters, the advantage of deluging the 



