48 PLANT PROPAGATION 
suitable for the operation outside, which should always 
be skilfully performed by means of clean cuts, a careful 
fitting of the parts together, and an exclusion of air by 
the application of grafting-clay or wax. 
Close frames or cool houses are requisite for tender 
plants and for various evergreen trees or shrubs until 
the parts have become united. Many of these do not 
require any clay or grafting-wax if kept moist, quite 
GRAFT : MODE OF TYING AND MODE OF SUPPORTING 
CLAYING, ; GRAFT. 
close, and shaded. Heat is unnecessary in the case of 
many hardy plants, a protection from the drying influence 
of wind and sun being all that is required. 
There are various methods of grafting that may be 
successfully practised, according to the size or variety 
of subject it is intended to propagate or to improve. 
The following are those most generally used, and are 
all subject to slight modifications in varied circum- 
stances. 
