theory that freezing temperatures may play
a vastly greater part in the development of the nut industry over the
entire country than is commonly supposed. Much of the evidence of damage
from this cause is of such nature as to be easily overlooked or
attributed to other causes. Trees and plants of many kinds have become
so accustomed to injury by freezing that they are able to recover
without the injury always being apparent. A few illustrations of this
which have come to the writer's attention might be cited.

In December 1919, a sudden drop in temperature of from 32 deg.F to 24 deg.F
occurred at McMinnville, Oregon, with fatal result to cultivated trees
and shrubs of many kinds. The damage was greatest in flat bottoms,
especially those where neither land nor air drainage was good. Under
such conditions, numerous apple orchards were killed outright. Prunes
and Persian walnuts were so badly injured to the snow-line that
subsequently great numbers of trees were cut down. Both staminate and
pistillate buds of filberts above the snow were practically all
destroyed. Later on, the entire tops of many of the older-bearing
filbert trees succumbed. An instance of particular interest, in so far
as this discussion is concerned, was afforded by the behavior of a
shagbark hickory tree in McMinnville, some 20 or 30 years old, which had
been grown from a Missouri seed. In February, when examination was made
of the condition of this tree, it was found that all visible buds had
been killed, yet the bark on the branches between the buds was in
apparently perfect condition. The question as to what the tree would do,
therefore, became one of great interest. The following September, when
revisited, this tree was found to have such a wealth of luxuriant
foliage that the observer felt that the accuracy of his February records
was challenged. However, closer inspection showed that growth had
entirely taken place from adventitious buds, and that the dead buds and
spurs were still in evidence. There were no nuts on the tree but
otherwise the casual observer would not have suspected that the tree had
been affected in any way. In all likelihood, the owner of the tree would
deny that it had been injured.

Another case of somewhat similar kind occurred early during the present
year in a pecan orchard in South Georgia. The trees had been set in
1917, and in 1919, a portion selected by the Bureau of Plant Industry
for conducting a series of fertilize