Complimentary 
NEW SERIES VOL. X 
NO. 13 
ARNOLD ARBORETUM 
HARVARD UNIVERSITY 
BULLETIN 
OF 
POPULAR INFORMATION 
JAMAICA PLAIN. MASS. JULY 17. 1924 
Native and Foreign Trees. The number of foreign trees here which are 
superior to those which grow naturally in New England is not a large 
one. The handsomest Poplar probably which is perfectly hardy here 
and grows successfully is Populus Maximowiczii, a native of eastern 
Siberia, eastern Saghalin and northern Japan. It is the largest tree 
of eastern Siberia where it sometimes grows eighty feet high with a 
trunk six feet in diameter, and has a broad head of massive spreading 
branches. On young trees the bark of the trunk is smooth and pale 
brown but on old trees it becomes thick and furrowed. It has been 
growing in the Arboretum since 1878. The oldest trees in the Arbore- 
tum are on the southern slope of Peter’s Hill and are now twenty-six 
years old and from forty to forty-five feet in height. They have 
never been attacked by borers which make the cultivation of the 
Balsam Poplars and some of the Cottonwoods so difficult and unsatis- 
factory, and their leaves apparently have no attraction for leaf-eating 
caterpillars; they are green and lustrous on the upper surface, silvery 
white below, three or four inches long and two and a half inches wide. 
Populus Maximoiviczii is the handsomest and most satisfactory tree in 
the Poplar Collection and is one of the few large exotic trees with 
deciduous leaves which can be recommended for general planting in 
the northern states. The list of such trees is a short one. The two 
Silver Poplars of Europe, P. alba and P. canescens, flourish in the 
United States where they have grown to a large size and are as much 
at home as they are in their native countries. The pale color of the 
foliage of these trees is unlike that of any of the American species, 
and their hardiness and vitality make them useful for planting in an 
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