After twenty years of experience I have 
never, so far as I know, lost a single 
Chestnut tree from winterkilling on my 
Blue Ridge Mountain slope in the Phila- 
delphia climate. Chinese Chestnut trees 
have thriven and borne for years in Con- 
necticut, some in Massachusetts, a few 
in southern Vermont. At the same time 
we get occasional reports of complete 
winterkilling in those same areas and lati- 
tudes. Why this difference? There are 
three main reasons, 
One is: Does your land happen to be in 
a frost pocket? Few persons realize the 
profound climatic difference that may 
exist between your house and the meadow 
that lies a short distance below it and 
happens to have poor air drainage. The 
figures on page 6 show an almost un. 
believable difference of temperature on a 
cold night. Indeed, the range was more 
than 12° F. in 50 feet difference in ele- 
vation—the difference in temperature be- 
tween 33° (which did not freeze) and 
21°, which if kept on long enough would 
have made ice thick enough to skate upon. 
I know two innocent looking fields near 
Washington, D. C. They are in a warmer 
climate than my Blue Ridge Mountain, 
but on one of them Chestnuts (which live 
perfectly for me) winterkill from time to 
time because it is a frost pocket, and on 
the other field, a short distance away, they 
do not winterkill, because it does not 
happen to be a frost pocket. 
The frost pocket trees will get much 
lower temperatures on still nights in mid- 
winter. Trees in a frost pocket will have 
new growth frozen in late spring while 
the tree on the overlooking hill escapes. 
Trees in a frost pocket will have their 
leaves killed in the autumn so that they 
cannot mature their fruit, while the trees 
on the nearby hill can breathe on for two 
or three weeks longer and finish up their 
year’s work. 
These early autumn freezes that catch 
a tree while still in active growth are 
particularly destructive because the tree, 
being full of sap, may freeze and split the 
bark. One year I had this happen to a 
number of Stayman Winesap apple trees 
under the following conditions. A careless 
stableman had manured them repeatedly 
through the summer because they were 
near the barn, and September had 11 
inches of rain; in late October, an un- 
usually early freeze. The heavily manured 
trees perished; the ordinary orchard es- 
caped. But a few trees at the outlet of 
roadside drains had benefited hy an ac- 
cumulation of soil and repeated soakings 
at every rain. They also perished of 
“winterkill.” Winterkill is often spring- 
kill or autumnkill. 
Second cause of winterkilling—late 
growth in autumn. See page 14 on English 
Walnut. 
The third reason why we cannot speak 
yet authoritatively about the northern 
limit of the Chinese Chestnut is that dif- 
ferent trees may differ in the length of 
the required rest period of the tree. 
Nearly all of our frost-climate trees need 
frost to put them to sleep in the autumn, 
and then they will stay asleep until they 
have had a certain number of hours of 
cold weather. Now different species vary 
in the length of the required rest period. 
And in some species the different trees 
within the species vary in this respect. 
For example, the Elberta peach requires 
1000 hours of temperature at 45° F., or 
lower, during the winter to complete the 
rest period and resume normal growth 
under favorable spring temperatures, 
while the Hiley and other varieties re- 
quire 700 hours of temperature of 45° F., 
or lower, in order to finish the rest 
period, which means that the Hiley will 
start growing in a warm spell in Febru- 
ary, while the Elberta sleeps on, in warm 
winters, 
It seems to be true that some varieties 
of the Oriental Chestnuts have a shorter 
rest period than the American Chestnut. 
It will take a number of years and much 
experimenting to find out the exact facts 
in this field. In the meantime we cannot 
say for certain that the Chinese Chestnut 
will grow in the exact northern limit of 
the American Chestnut. But I am propa- 
gating one variety from a tree that has 
stood unharmed for many years in south- 
ern Connecticut. 
These trees resist winter better after 
they have had a few seasons to re-estab- 
lish their root and top ratios and get set- 
tled into the new home. 
All these nuts are of beautiful brown 
color like the native American Chestnut 
and slightly larger. On an eating test you 
would have great difficulty in telling 
which was American and which Asiatic. 
Let the nuts shrivel a little to develop 
flavor before eating. 
For varieties see price list. 
