10 
A tree of northern China now considered a variety of Pyrus ussuriensis 
(var. ovidea) is an older inhabitant of the Arboretum. It blooms two 
weeks later than the more northern tree; the flowers are larger and 
pure white; the fruit, too, is larger with a yellow skin and succulent 
flesh and unlike that of other Pear-trees is broad at base and narrow 
at apex. The leaves turn brilliant scarlet; and in the autumn the large 
tree standing on the left hand side of the Forest Hills Road, near the 
Arboretum entrance, is a conspicuous object. 
Pyrus Calleryana, a handsome and shapely tree raised from seeds 
collected by Wilson in western China has grown rapidly in the Arbor¬ 
etum where it has flowered and produced fruits for several years. This 
tree promises to be one of the most valuable plants introduced by the 
Arboretum into the United States for the innoculation of its seedlings 
has shown, as far as such tests prove anything, that they are immune 
to attacks of the blight which has been the destruction in the United 
States of many varieties of garden Pear-trees. Pomologists, therefore, 
now believe that they have found in this tree the stock which will make 
the cultivation of pears in this country a more certain and profitable 
industry than it has been since the Pear-tree blight became prevalent. 
Many thousand seedlings of Pyrus Calleryana have been raised by the 
Department of Agriculture of the United States and by different exper¬ 
imental stations from the seeds produced by the Arboretum trees, and 
if these seedlings prove as valuable as American pomologists now be¬ 
lieve them to be they will show the country the value of museums like 
the Arnold Arboretum, and more than justify the labor and money it 
has expended in its explorations in eastern Asia. Unfortunately the 
only specimens of this tree outside of China which produce large crops 
of fruit are in this Arboretum, and the supply of seeds will for some 
time longer be insufficient to meet the demands for it. The large white 
flowers and ample, dark green leaves make Pyrus Calleryana a valu¬ 
able garden plant; the small glabrous fruit is hardly more than a third 
of an inch in diameter. 
Pyrus serotina, another of Wilson’s introductions from western China, 
is of special interest to the students of cultivated fruits as it is the 
wild type from which have been derived the hard, round, gritty pears 
which have been cultivated for centuries by the Chinese and Japanese. 
These cultivated oriental pears are often handsome trees with beautiful 
flowers and greenish yellow fruits which are often extremely ornamen¬ 
tal, but western palates and digestions cannot cope with the hard fruits 
with cells filled with grit. These Japanese Sand Pear-trees crossed with 
European Garden Pear-trees several years ago produced in the United 
States the Keiffer and Lecomte Pears. These, although rather hard, 
are handsome and suited to long shipment. Much was expected of 
them especially in the southern states where large orchards of these 
trees were planted. The trees proved so susceptible to blight that their 
cultivation has been practically abandoned. Pyrus serotina has grown 
with remarkable rapidity in the Arboretum and in spring is covered 
with large flowers more or less deeply tinged with rose and unfolding 
deep bronze-colored leaves. 
Pyrus Bretschneideri is the only Chinese Pear-tree which some day 
