102 GARDENING FOR THE SOUTH. 



not enough. The most common way of obstructing the 

 return flow of sap is when the shoot is bent into the earth 

 to half cut it through near the bend, the free portion of 

 the wound being 'called a tongue. This is kept open 

 by a bit of twig, or piece of crock. Such layers are in 

 fact cuttings, only partially separated from parent-plants. 

 The incision is made through the bark at the base of a 

 bud. The object of the gardener is to induce the layer 

 to emit roots into the earth at the tongue. There are 

 other modes of effecting this. 



With this view, he twists the shoot half round, so as to 

 injure the wood vessels ; he heads it back so that only a 

 bud or two appears above ground, and when much water- 

 ing is required, he places a handful of silver sand around 

 the tongued part, then pressing the earth down with his 

 foot, so as to secure the layer, he leaves it without further 

 care. The intention of both tongueing and twisting is to 

 prevent the return of the sap from the layer into the main 

 stem, while a small portion is allowed to rise out of the 

 latter into the former. The effect of this operation is to 

 compel the returning sap to organize itself as roots, in- 

 stead of passing downwards to form wood ; the bending 

 back is to assist this object, by preventing the expenditure 

 of sap in the completion of leaves. The bud left on the 

 tongue favors the emission of roots, as a tendency exists in 

 nearly all plants to throw out roots at the joints, and the 

 silver sand secures the drainage so necessary to cuttings. 



The old mode of forming the tongue, and the best, un- 

 less the shoot is brittle, is shown in the figure, where 

 the tongue is shown upon the underside of the layer. 

 " A plan," says the Gardener's Monthly, " which is now 

 much in vogue with the best propagators, is to cut the 

 tongue on the upper surface. On bending down into the 

 soil, the tongue is then twisted on one side, and the young 

 shoot intended to form the future plant may then be lifted 

 up and bent towards the parent as rapidly as one pleases, 



