6 
is remarkable in the case of the typical species which is a northern 
tree common and of large size on the plains and mountain sides in the 
neighborhood of Peking, where conditions for successful tree growth 
are as unfavorable as they can well be. The fact that this tree of 
northeastern Asia is not perfectly hardy here shows that the ability of 
a tree to flourish in any region in which it does not grow naturally 
cannot be determined by the knowledge of the climate and soil condi- 
tions where it grows naturally, and that only experiments carried on 
through long periods can show the value of an exotic tree in any for- 
eign country. The variety densata of Pinus sinensis has suffered even 
more than the type, although the plants of most of them will proba- 
bly recover. This variety reaches higher altitudes than the other 
Chinese Pines, growing up to 12,000 feet in western Szech’uan, where 
it is common, and southward forms great forests. This tree as Wilson 
saw it resembles the Scotch Pine {Pinus sylvestris) in habit and gen- 
eral appearance, with a tall clean trunk, massive branches forming a 
rounded or flattened head, and pale red bark on the upper stem and 
branches. The variety yunnanensis of Pinus sinensis has suffered less 
than the var. densata, although it is a tree of river valleys and lower 
levels in southwestern Szech’uan and ranges much farther south. This 
tree differs from other forms of Pinus sinensis in its longer, more 
slender, darker green, drooping leav-^es, in its longer cones, in the 
brighter red bark on the upper stems and large branches, and in its 
usually more pyramidal habit. If this Pine, which was raised at the 
Arboretum in 1909, really succeeds in this climate it should make a 
valuable addition to the comparatively small list of ornamental conifers 
which can be grown successfully in New England. In the Arboretum 
Pinus Thunbergii, the great Black Pine of Japan which lines many of 
the highways of southern Hondo, has again lost many leaves, and 
although this tree was uninjured here for nearly a quarter of a cen- 
tury it has suffered so much in some of the severe winters of recent 
years that it now seems doubtful if it can adapt itself permanently to 
this climate. It is unfortunate, for no Pine-tree is more picturesque 
in habit or more distinct in its beautiful white buds. It is a matter 
of interest that the new Chinese Spruces have been uninjured by the 
winter. The introduction of these plants into cultivation is one of the 
important results of the botanical exploration of China undertaken by 
the Arboretum, and of these Spruces only Picea Sargentii has shown 
itself unable to grow in this climate. 
Broad-leaved Evergreens have suffered from the extreme and unu- 
sual heat of several March days followed by days and nights of low 
temperature. The damage in the Arboretum is less, however, than in 
several other gardens in eastern Massachusetts. The Arboretum Rho- 
dodendrons, thanks to the exceptionally good position where they are 
planted, look unusually well. Of the small number of species which 
can be grown in this climate none have suffered, and of the Catawbi- 
ense Hybrids only a few have been slightly injured in the loss of an 
occasional branch or a few leaves. Laurels {Kalmia latifolia), which 
are rarely hurt by extreme cold or March changes of temperature, are 
now disfigured by brown and dried leaves at the ends of the branches 
of several plants; and leaves on the large plants of the native Inkberrry 
