Prunus triloba is in flower just below the entrance to the Shrub 
Collection at the Forest Hills Gate. This is a shrub with bright clear 
pink flowers about an inch in diameter which appear before the leaves. 
The double-flowered form of this shrub (var. multiplex) is a favorite in 
China, whence forty or fifty years ago it was introduced into Europe 
and the United States where it is often cultivated. The much more 
beautiful single-flowered form grows on the mountains near Peking 
and appears to have been cultivated for the first time in the Arbore- 
tum, to which seeds were sent from China in 1882. Although perfectly 
hardy, P. triloba is not a particularly vigorous plant. It well deserves 
a place, however, in every garden for the charming color of the flowers. 
The Plum trees in the group next to the Cherries and at the princi- 
pal entrance to the Shrub Collection from the Meadow Road are be- 
ginning to open their flower-buds. This year the Chinese Prunus tri- 
flora is the first to flower. It is a common fruit tree in China and 
Japan, and from it or from some of its varieties the so-called Japan- 
ese Plums, now so popular in the United States, have been derived. 
The flowers of this Asiatic tree will soon be followed by those of the 
Canada Plum ( Prunus nigra ) which is the most northern of the Amer- 
ican Plum trees, being distributed from Newfoundland to the shores of 
the Strait of Mackinaw and southward along the northern borders of 
the United States. It is a small tree with dark, rough bark, and 
flowers slightly tinged with pink and becoming rose-color in fading. 
This, perhaps, is not one of the handsomest of the American Plum- 
trees, but it is valuable on account of its hardiness, the early appear- 
ance of the flowers, and the early ripening of the fruit. The Plum 
Collection is near the principal entrance to the Shrub Collection from 
the Meadow Road and next to the Cherries. 
The Arboretum collection of Willows is planted on both sides of the 
path which, starting from a point opposite the Administration Building, 
leads to the Shrub Collection and to the Forest Hills Gate. The col- 
lection, which contains a large number of species and hybrids, suffers 
for want of sufficient space for the proper development of individuals, 
especially of the species which become large trees, and on the whole is 
less satisfactory than some of the other groups in the Arboretum. Some 
of the dwarf shrubby species are now in flower and should be examined 
by persons in search of beautiful hardy shrubs suited for many deco- 
rative purposes. One of the most beautiful of these little Willows is 
Salix tristis, a spreading shrub not more than two feet high with slen- 
der stems and small gray-green leaves. The anthers of the male plant 
are bright red when they first appear and much more showy than the 
gray inflorescence of the female plant. This little willow grows natu- 
rally on dry barren soil from New England to Minnesota and south- 
ward. It takes kindly to cultivation and grows equally well on dry 
ground and in moist peaty soil, and soon spreads into large masses. It 
is an excellent plant for covering dry barren slopes. Salix humilis is 
another native shrub with gray-green leaves but yellow anthers. This 
species sometimes grows to the height of from six to nine feet, and 
the slender red stems make a handsome contrast with the silvery gray 
flower-clusters. This is also a plant of the northern United States and 
is as easily cultivated as S. tristis in all sorts of soil. In the same 
group are also flowering two dwarf exotic species, Salix repens var. 
