42 
THE NATIONAL NURSERYMAN 
WINTER STORAGE . 
Present Methods Among Nurserymen Outlined and the Disad¬ 
vantages and Advantages Noted — Changes in Tem¬ 
perature—As to Moisture—Trenching 
Trees for Winter. 
Some of the nurserymen who do not advocate winter 
storage, admit the need of something better than spring 
digging by “heeling in” or “trenching” their trees for the 
winter in a protected place which will drain naturally. They 
admit that this allows of possible damage to the tops of the 
trees in severe weather, but it saves time and wet digging 
in the spring. As an improvement over this it is only an¬ 
other step in the solution of our problem to put a shed over 
these heeled-in trees to protect the tops from low temperature 
during severe weather. This is a common method and is 
practiced by some very large nurserymen. A frost proof 
cellar or shed is provided in which the trees are heeled-in 
in the fall, so as to have them ready for spring shipment. 
The storage shed is kept at the freezing point or somewhat 
above, so that sorting, grading and packing may go on in¬ 
dependent of weather conditions outside, enabling shipments 
to be made as early as desirable in the spring. Much storage 
space is needed with this method and under some conditions 
the trees may dry out or shrivel, but the heeling-in storage 
method has the advantage of being more independent of 
temperature changes than where the stock is piled up with 
roots exposed. A change of temperature is largely what 
causes the drying out of trees, owing to the change of humid¬ 
ity with the temperature changes. 
STRUCTURAL CONDITIONS. 
Most of the winter storage structures in service are built 
partly below the surface, but many of the largest are wholly 
above the ground. Nearly all are insulated by building air 
spaces into the w r alls or by a filling of shavings, sawdust or 
similar non-conducting materials. It is the idea in building 
partly below ground to secure the protection afforded by 
the earth. It is a well known fact that at a depth of a few 
feet below the surface of the earth a nearly stationary tem¬ 
perature of about 55° F. may be obtained winter and summer. 
This will prevent freezing in winter if the cellar is rightly 
built, but it will likewise cause a marked rise in temperature 
whenever a winter thaw occurs and it becomes necessary to 
close the building tightly. The heat of the earth will then 
work up into the storage room and a temperature of 40°F. to 
50°F. may result. Another disadvantage of the cellar is 
that when the first trees are stored during the fall, the surface 
of the earth is quite warm, and it is very difficult to keep 
the temperature of the cellar low enough. Ventilators, 
windows and doors are opened on a cold day or at night, and 
in this way the temperature is, after considerable delay, 
finally reduced to the desired point. A warm spell alter¬ 
nating with cold weather in the fall after storing commences 
will result in a great deal of damage by causing the temperature 
of the cellar to vary greatly. A variation of temperature 
and consequent variation of humidity will cause a drying 
out or shriveling of the trees, and may cause a growth of 
mold or mildew. 
A building wholly above ground has many of the disadvan¬ 
tages above mentioned, and also the disadvantage of lack of 
protection during extremely cold weather. There are, how¬ 
ever, advantages in above ground construction in that the 
building if of frame construction will not rot out as quickly, 
and it may be cooled more readily in the fall, and it is not 
affected so much by heat from the earth. It is stated by 
many nurserymen that temperatures are very difficult to 
maintain in any of the ordinary sheds or cellars in use, espe¬ 
cially during the storage season in the fall and during the 
shipping season in the spring. Winter storage for nursery 
stock should be so arranged that when natural temperature 
is suitable, air may be taken from the outside and forced into 
the room for refrigerating and when natural temperatures 
are not suitable, as during a warm spell in fall or spring, or 
during a winter thaw, artificial refrigeration may be applied. 
Moisture brought in with stock—especially if the fall has 
been a wet and warm one—might cause mold. A proper 
cooling and temperature regulating system would prevent 
this. 
CHANGES IN TEMPERATURE. 
From the data at hand, it seems clear to the writer that 
practically all of the damage to nursery stock experienced 
in winter storing in cellars or sheds as ordinarily practiced 
comes from changes of temperature, and a generally too high 
temperature, which cannot by present methods be avoided 
It has been noted that trees dug late in the fall and placed 
in storage after the temperature of storage-room has been 
reduced to about the freezing point have carried through in 
better condition than those dug at an earlier date and placed 
in storage while the temperature of the room was still com¬ 
paratively high. This may be partly because the wood is 
more dormant, but it is probably largely because it is easier 
after about November 15th to keep down the temperature 
of the storage room. A high temperature and frequent 
changes of temperature will cause stock to dry out and shrivel. 
This is especially true of vegetation of quick growth such as 
peach trees. To prevent this drying out, a spraying with 
water is often resorted to, but this again leads to mold or 
mildew if the temperature is high and not very carefully 
handled. 
AS TO MOISTURE. 
One nurseryman states: “When stock is put in late in 
October and November, it needs no wetting at all, but stays 
damp all winter and spring;” another says: “In our own 
case, we find on account of the ups and downs of temperature, 
we must sprinkle with water more or less, but we believe that 
with a fixed temperature that did not vary to any great 
extent, the water could be omitted.” No better argument 
could be made for low and uniform temperatures. There is 
no question at all that trees may be dug any time after October 
1 st, or after the tree is dormant from natural causes, placed 
in a temperature of 28°F. to 30°F., held steadily until spring, 
and come out in better condition for planting than stock 
allowed to remain in the nursery all winter and dug at the 
shipping time. Humidity must be attended to, but this is 
very easy to regulate at the low temperatures mentioned. 
As to temperatures at w r hich trees should be held t here seems 
to be a wide difference of opinion, no doubt this opinion is 
