PROPAGATION OF PLANTS. 203 



gently draw a little of the soil into the trench covering 

 the parent cane, and as the shoots increase in strength, 

 till up the trench, and each young shoot will make a fine 

 plant by autumn. 



In general, the best season for layering is before the 

 sap begins to rise in the spring, or, in the case of wood 

 of the same season's growth, in the summer after June. A 

 good time for roses is after the first bloom is over. Lay- 

 ered at this time, they will generally be fit to take up the 

 ensuing winter, but most plants require twelve months, 

 and some two years, before they will root. In nurseries 

 the ground is prepared around each stool by digging and 

 manuring, and the branches laid down neatly, so as to 

 form a circle of rays around the stool, with the ends rising 

 all around the circle to about the same height. 



Cuttings. — A cutting is a part of a plant detached from 

 the parent stock, which, placed in proper conditions, will 

 emit roots and become in its turn a new plant. It may be 

 a portion of the stem, the branches, or the root, and some- 

 times even a leaf. 



In a cutting, as in a growing plant, two forces are in 

 constant activity, those of absorption and of evaporation. 

 Its life cannot be long continued, unless these correspond 

 with each other. A cutting, from the lack of roots, absorbs 

 feebly from the soil; hence evaporation must be dimin- 

 ished to correspond, and the base of the cutting must be 

 in contact with a substance more or less humid. Evapora- 

 tion is diminished by planting in a northern exposure, 

 shading, the use of bell-glasses, etc. The more herbaceous 

 or immature a cutting may be, the greater care is required 

 to protect it from excessive evaporation. 



Cuttings of hardy deciduous trees and shrubs should 

 be taken off after the leaves fall, or before the sap rises in 

 the spring. Those that strike readily in the open ground 

 in mild climates may be planted out to form the callus, 



