50 FERNS 



mass, without a depression, seam or furrow 

 in which plant life of any kind could gain a 

 foothold. Indeed, one might' as well attempt 

 to grow hair on an eggshell as to make even 

 Boston ivy (Ampelopsis tricuspidata) cover the 

 glaring surface. Obviously there are rocks 

 and rocks. Those which are absolutely of 

 no use and have no beauty are out of place 

 on any lawn. 



SOILS FOR ROCK PLANTS 



Rock plants in general require light, 

 sandy soil mixed with old mortar, if de- 

 composed limestone is not at hand; brick 

 rubbish also makes a satisfactory mixture. 

 Certain species require a richer and lighter 

 compost in which leaf-mould predominates. 



BUILDING ON LAWNS 



In building rockeries on our lawns we may 

 follow general principles but may not imitate 

 Nature in detail of construction, for too much 



