BULLETIN NO. 6. 
Many of the Rhododendrons in the collection at the base of Hemlock 
Hill are now in flower and can be most easily reached from the South 
Street entrance. Owing to the heat and drought of May the flowers are 
smaller than in more favorable seasons and they will probably not last 
long in good condition. 
The variety of these plants which can be successfully grown in this 
climate is not large, and they are mostly derived from a few species. 
The most important of these species are three Rhododendrons of the east- 
ern United States —Rhododendron catawbiense, Rhododendron puncta- 
tum and Rhododendron maximum. The first grows only on the high sum- 
mits of the southern Alleghany, Mountains where it sometimes covers 
enormous areas, but is rarely found much below an altitude of five thous- 
and feet. This plant is very hardy and in cultivation forms a broad, low 
bush; it grows slowly, however, and the flowers are of a rather disagree- 
able purplish rose color. It is most interesting for the part which it has 
played in the production of the principal race of garden Rhododendrons. 
Several plants are now in flower along the drive not far from the South 
Street entrance. The second species, Rhododendron punctatum , is also a 
native of the southern Appalachian region where it grows at much lower 
altitudes than Rhododendron catawbiense. It forms a dense low bush 
with small leaves thickly covered on their lower surface with dark dots, 
and small, reddish purple flowers in small compact clusters which are a 
good deal hidden by the young branches which, growing before the flow- 
ers open, overtop them. This plant, of which there are good specimens 
in the collection, will not be in bloom for several days. There are two 
hybrids of this species known in gardens as Rhododendron Wilsoni or 
arbutifolium, and Rhododendron myrtifolium. The former is a cross 
with the alpine Rhododendron ferrugineum and the latter with the alpine 
Rhododendron hirsutum. In habits and foliage they are handsomer plants 
than their American parent, and are useful for small gardens and for the 
margins of beds of larger plants; they will not be in bloom for several 
days. Rhododendron maximum , the third of the American species, is 
found occasionally in New England swamps and is very common along the 
borders of streams in mountain valleys south of New York, often grow- 
ing to the size of a small tree and sometimes forming impenetrable thick- 
ets of large extent. This is the latest of the Rhododendrons to flower 
here and will not be in bloom for several weeks. The flowers and the 
flower-clusters are much smaller than those of Rhododendron catawbi- 
ense and, like those of Rhododendron punctatum , they are hidden by the 
branchlets of the year which surround and rise above them. A hybrid of 
Rhododendron maximum and Rhododendron catawbiense , raised in Eng- 
land and known as Rhododendron delicatissimum, is in this climate one 
of the most beautiful and desirable of garden Rhododendrons. It has 
white flowers tinged with pink, which appear after those of most of the 
other catawbiense hybrids have passed. Another English hybrid of the 
same parentage, Rhododendron Wellesley anum, is less hardy here than 
either of its parents; and among a large number of seedling plants of 
Rhododendron maximum crossed with some of the red-flowered catawbi- 
ense hybrids, raised near Boston, only a few have been able to bear the 
cold of the New England winters. Other species in the collection are the 
