Means of Propagation 



the sap flows from the old plant to the young. 

 But sooner or later the relation is broken off ; 

 the runners, having become useless, dry up, 

 and each growth, properly rooted, becomes a 

 separate plant. We find here, apart from 

 human industry, all the incidents of layering : 

 the artificial operation finds its equivalent, 

 and no doubt its model, in the natural 

 process. A long branch bends towards the 

 ground and is then detached from the parent 

 stock by the destruction of the runner. In 

 the same way the gardener buries a long 

 branch in the ground, waits for it to produce 

 adventitious roots, and then separates it with 

 his shears, and this is layering. 



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