PROPAGATION BY LAYERS. 43 



growth ; on arriving at the lower end of the shoot, 

 it expends itself in the production of new roots, 

 which shoot downwards into the soil. A new 

 plant or tree is thus formed. This method of pro- 

 pagation is applicable to such species only as rea- 

 dily throw out roots, as the currant, gooseberry, 

 quince, and grape. * A shoot should be taken of 

 sufficient length, to contain a good portion of sap 

 within it ; and to keep it from drying, it is best to 

 place the cutting below the surface, except one or 

 two buds on the upper extremity. Even these may 

 be covered with leaves or moss. Some operators 

 are careful to cut off the lower end close to a leaf- 

 bud, or close below a joint if the cutting is a vine, 

 believing it facilitates more readily the emission of 

 roots, which the thick, hard bark obstructs. 



II. LAYERS. 



Many plants which cannot be increased by 

 cuttings, and indeed with great difficulty by bud- 

 ding and grafting, may be propagated readily 

 by layers. This consists in bending down the 

 tranches to the ground, and covering the mid- 

 dle portion with soil. This portion takes root, and 

 then the branch is separated. Layers differ from 



* Cuttings of the apple and pear, are sometimes made to 

 strike roots, when placed in very favorable circumstances 

 under a bell glass to confine the moisture; but in open air, 

 never. The stories which go the rounds of the papers every 

 few years, of making trees by sticking cuttings into potatoes, 

 or covering them with wax, are not founded on fact. 



