i8 PRESENT-DAY GARDENING 



R. Brookianum, R. multicolor, and R. Malayanum. Judging 

 by herbarium specimens, there are many more than these 

 with strong claims to the attention of horticulturists. Under 

 cultivation they have proved to be too tender to thrive 

 in the ordinary greenhouse, subtropical conditions being 

 necessary for them. A useful race of perpetual-flowering 

 hybrids and seedlings has been raised from the several 

 species named above. They cross freely with each other, 

 but all attempts to breed a hybrid between this and either 

 of the other sections of the genus have so far failed. 



NORTH AMERICAN 



There are sixteen species of Rhododendron in North 

 America, one of which, R. maximum, the Rose Bay, is 

 arborescent. The other evergreen species are R. cali- 

 fornicum, R. macrophyllum, R. punctatum, and R. catawbiense, 

 the last named being one of the parents of the popular 

 garden race of hardy sorts. It grows on the summits of 

 the Alleghany and Appalachian mountains, often forming 

 dense thickets through which the traveller can make his 

 way only by following old bear paths. Here also grow 

 some of the deciduous Azaleas or Swamp Honeysuckles, 

 such as R. arborescens, R. calendulaceum, R. nudiflorum, and 

 R. viscosum. These colour wide stretches of country when 

 they are in flower in May or June. In an account of a 

 trip in June 1892 to the Roan Mountain in North Carolina, 

 Professor Sargent gives the following particulars of R. 

 catawbiense, which was then in bloom : " Along the borders 

 of the forest, sometimes scattered individually and often in 

 broad masses, covering hundreds of acres, the Rhododendron 

 grows, mixed with bushy plants of the Mountain Alder. 



