THE STEM AND THE LEAF 



69 



native countries. The process of shedding the leaf is a some- 

 what complicated one, being brought about by the formation 

 of a waterproof layer of tissue at the base of the leafstalk, 



FIG. 56. An evergreen rhododendron, typical of leathery-leaved 

 non-deciduous dicotyledons, in very early spring 



A deciduous rhododendron (azalea) is seen leafless in the foreground 

 Photograph by Robert Cameron 



thus cutting the leaf off from communication with the stem. 

 Before this is formed, the plant food in the leaf has usually 

 been conveyed into other parts of the plant, so that when the 

 leaf falls it takes with it little of value. 



