3o8 



NATURE-STUDY 



stem has been studied, modifications of stems should be 

 considered, to show how an organ may become adapted for 

 an entirely different function. 



Strawberry runners are long, slender branches sent out 

 above the ground by the plant, which radiate from it, strik- 

 ing root and sending up 

 a cluster of leaves at the 

 joints. In time, if left 

 naturally, the connecting 

 runner would die and 

 decay away, thus leaving 

 a number of separate 

 plants that at one time 

 were all one. This is a 

 device for propagation. 

 The gardener utilizes this 

 artificially in obtaining 

 new plants for setting 

 out. 



The long, drooping 

 branches of currants, 

 raspberries, and other 

 plants touch the ground with the ends and strike root there, 

 thereby starting another plant by a method similar to that 

 employed by the strawberry. 



Try some simple experiments in layering, slipping, and 

 grafting. (See last chapter.) 



Underground Stems: There are other pecuhar modi- 

 fications of stems for the purpose of propagation. Many 

 plants have underground shoots and stems which help them 

 to tide over a period of cold or dryness, or by which they 



Fig. 113. The White Birch. 



