PROPAGATION OF PLANTS. 201 



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

 the tongued part, theu 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 saj) 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 pre- 

 venting 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 



Fig. 81 — Layering. 



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

 sand secures the drainage so necessary to cutting. 



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

 unless 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, 

 without any danger of it snapping off. There is another 

 advantage in this way of layering. It is often necessary, 



