BULLETIN NO. 43. 
For the decoration of northern gardens there are no more beautiful 
or desirable shrubs than the Azaleas of eastern North America. There 
are seven species of these plants and they are now all called Rhodo- 
dendrons by botanists, and in the Arboretum all Azaleas are labeled 
Rhododendrons. The first species to bloom, R. Vaseyi, begins to flower 
the beginning of May and the flowers of the last, R. viscosum, can be 
found here as late as the middle of July, so that the Azalea season is 
a long one. R. Vaseyi is a tall shrub, with slender stems and an open 
irregular habit. In its home in the sheltered valleys of the Blue Ridge 
in South Carolina it sometimes grows to the height of from fifteen to 
eighteen feet. The flowers are produced before the leaves appear in 
small compact clusters and are pure pink in color, but occasionally 
plants are found with nearly white flowers. Although this plant was 
not discovered until comparatively a few years ago, it has been much 
planted in gardens near Boston and it is fast becoming here one of the 
most popular of the early-flowering spring shrubs. With R. Vaseyi the 
Rhodora (R. canadense) flowers. This well known dwarf shrub often 
covers, especially in the north, large areas of moist or swampy land 
with a sheet of bloom. The small flowers, however, are of a rather 
unattractive rose-purple color, and the fame of the Rhodora is perhaps 
due more to Emerson’s poem than to its intrinsic beauty. Naturally 
the Rhodora grows from Newfoundland to Pennsylvania and New 
Jersey. 
The next to bloom are the two pink-flowered species, R. canescens 
and R. nudiflorum ; the former is a northern and the latter a more 
southern plant and is especially common in the Gulf States from Flor- 
ida to eastern Texas. The flowers of these plants open before or with 
the unfolding of the leaves and in early spring fill the woods with 
beauty and fragrance. Both species can now be seen in flower on 
Azalea Path, and there is a large mass of Azalea canescens on the 
right-hand side of the Meadow Road in front of the Linden Group. 
The Flame-colored Azalea, R. calendulaceum , is the next species to 
flower and is already beginning to open its orange, yellow, or reddish 
flowers which are not fragrant. This shrub is an inhabitant of the 
Appalachian Mountain region from southern New York to Georgia, and 
is extremely abundant on the lower slopes of the high mountains of 
North Carolina and Tennessee. In flower it is the most showy of our 
Azaleas and one of the most beautiful of all flowering shrubs. A large 
mass of this Azalea has been planted on the slope below Azalea Path 
and occasional large specimens can be seen in the border plantations 
along some of the roads. 
The next species to flower, R. arborescens, is also a native of the 
Appalachian Mountains on which it grows from Pennsylvania to Geor- 
gia and where in sheltered valleys it sometimes attains the height of 
fifteen feet or more. The flowers, which appear after the leaves are 
nearly fully grown, are white or faintly tinged with rose color and are 
made conspicuous by the long bright red filaments of the stamens. 
The flowers are very fragrant and the young leaves have the odor of 
new mown grass. Less showy in flower than the Flame-colored Azalea 
it is one of the most beautiful of all hardy Azaleas. 
