Gbe IRational IRurseryman. 
FOR GROWERS AND DEALERS IN NURSERY STOCK 
The National Nurseryman Publishing Co., Incorporated 
Vol. XXVIII. HATBORO, PENNA. MAY 1920 NoTT 
Tests of New Pear Stocks 
By B. T. Galloway, U. S. Department of Agriculture. 
P ROBLEMS connected with the securing of suitable 
stocks for certain of our important fruits and or¬ 
namentals like the apple, pear, plum, cherry, and 
rose are becoming more acute each year. The pre-war 
foreign sources of supply of many of our common stocks 
have become uncertain and unreliable, and while there 
are no restrictions on importations of these types, there is 
every reason to believe that we must look more and more 
to home production to meet the future needs of American 
fruit growers. 
We are confronted with two problems in connection 
with this stock matter: (1) to find ways, means, and 
methods of producing home supplies of the common 
stocks, especially the apple, pear, plum, cherry, and rose, 
and (2) to discover new stocks better than those com¬ 
monly used, to demonstrate by experimentation and field 
tests their value, and to encourage the establishment of 
permanent sources of supply here. We are particularly 
interested in the second group of problems, namely, the 
discovery and bringing into use of new stocks that may 
take the place and prove superior to the old ones, and that 
may be economically produced by nurserymen and others 
in this country. To this end, we are engaged in as¬ 
sembling for study, tests, and experimental work collec¬ 
tions of apples, pears, plums, cherries, and roses that 
have promise of value for stock purposes. 
The Office of Foreign Seed and Plant Introduction in 
the United States Department of Agriculture has had 
these activities under way for a number of years. Here¬ 
tofore the work has been largely confined to seeking out 
in foreign parts species, varieties, and types of these new 
fruit and ornamental plants and getting them established 
here, with a view to ultimate systematic study and ex¬ 
periments, looking toward the improvement and stabiliza¬ 
tion of horticultural practices. 
There can be no question that the stock problem is one 
of the big problems in horticulture today. We refer es¬ 
pecially to the problem of particular stocks for particular 
purposes, disease and insect resistant stocks, adaptation 
of stocks to our wide and varied soil and climatic condi¬ 
tions, congeniality of stock and scion, etc. 
These notes are intended to call attention to several 
promising pear stocks which have been the subject of 
study and experimentation for some time. Out of several 
hundred different kinds of pears studied, there are four 
deserving of special notice at this time for stock purposes. 
We will refer to them in the order of what appears to be 
tlieir value. We say “appears” because any study of 
stocks is a long time proposition. The work so far done 
has been mainly in the nursery and the results there are 
encouraging and promising. 
The calleryana pear (Pyrus calleryana S. P. I. No. 
44044.) is a wild species found in many parts of China 
and sparingly in Japan. It is a vigorous growing tree 
with small, hard, inedible fruits. It fruits and seeds 
abundantly. A tree at the Arnold Arboretum has stood 
the winters for the past twelve or thirteen years. Some 
of these winters have been extremely severe. This tree 
is a prolific seed bearer. We believe it would be safe to 
estimate from 10,000 to 12,000 seedlings per year for each 
tree ten to twelve years old. Through the courtesy of Dr. 
C. S. Sargent, the Director of the Arnold Arboretum, we 
have been able to secure several thousand seedlings from 
this tree each year for the last two or three years. Sev¬ 
eral collections of the seed of this pear were made in 
China by the late Frank N. Meyer. Just prior to his 
death, he succeeded in getting more than a hundred 
pounds of the seed from central China. The seedlings of 
the calleryana pear are easily grown, have good roots, 
and hold their leaves remarkably well even where leaf 
blight is severe. This species is very resistant to fire 
blight. In comparison with French and ordinary Japan¬ 
ese stocks the budding season is two or three times as 
long; in fact, wherever tried the trees may be budded 
from July to September. 
There appears to be several strains or types of the 
calleryana pear. One or two of these are from the 
warmer sections of China, hence, are not so hardy as 
those that come from farther north. Seeds are not yet 
commercially available. From what we know of the 
sources of supply in China, it will probably be difficult to 
secure reliable seed in quantity. It is believed, there¬ 
fore, that we must look forward to the establishment of 
sources of supply here. With this end in view, we have 
been growing trees for permanent plantings. It is our 
desire to place these trees, of which as yet we have but a 
limited number, in the hands of nurserymen and others 
who may he ready and willing to co-operate to the end of 
securing home supplies of seed. We are also encourag¬ 
ing the top-working of other pears, preferably Kieffer, 
with this pear for seed production purposes. Scion wood 
and budwood of the tree can be furnished in season. 
The Chinese water pear (Pyrus usuriensis, Cult. var. 
S. P. J. No. 44235) another promising type for slocks, 
was first collected by the late Frank N. Meyer in northern 
China. The wild Pyrus usuriensis, of which the water 
pear is a cultivated variety, is very resistant to fire blight, 
but not so resistant to leaf blight as calleryana. The wild 
usuriensis, furthermore, is a slow grower and, there- 
