"hardy" rhododendrons 251 



where only recently it has been discovered. Of the 

 American species of this group five are well estab- 

 lished in the Arnold Arboretum and no group of 

 plants perfectly suited to our climate surpasses 

 them in beauty. The first to open their flowers are 

 R. canescens and R. nudijlorum. Both have fragrant 

 pale rose or pink flowers of various shades which 

 appear before the leaves or just as they begin to 

 unfold. In general appearance these two plants 

 are very similar but one is a southern and the other a 

 northern plant though there are places where they 

 grow together. The plants are twiggy, of medium 

 size, and grow singly or in great masses on treeless hill- 

 sides or in open woods. Rhododendron canescens is 

 very abundant in parts of Worcester County, Mass., 

 and if. nudijlorum is especially common in the Gulf 

 States from eastern Florida to eastern Texas. 



The next to blossom is R. calendulaceum, the Yellow 

 Azalea of the Appalachian Mountain slopes which 

 opens its flowers early in June. The color varies 

 from bright yellow to orange or shades of red and 

 the beauty is heightened by contrast with the dark 

 green leaves which are well grown before the flowers 

 open. It is a rather slow-growing but long-lived 

 plant, from eight to ten feet tall, and the beauty of 

 its brilliant-colored flowers is not surpassed by those 



