wed evidences
of bark splitting and this was undoubtedly caused by a severe and sudden
cold spell following a very late and extremely vigorous growth. Scions
of this strain were grafted on a medium sized black walnut at Caro,
Michigan, and these endured -30 degrees F. without serious injury. A
small black walnut tree at the Kellogg Farm top-grafted to scions of
another Crath seedling showed bark injury on the lower half of the
stock, but fortunately the extent of the injury was not great and the
graft was saved. It also made a vigorous growth this season
notwithstanding the hot dry weather and injury to the bark on the stock.
Scions of this strain were grafted on a vigorous black walnut on the
farm of F. Wilde at Wayland in 1933. These scions made an extraordinary
growth that season and were subjected to a temperature of -20 degrees F.
last winter. Some killing back occurred but no permanent injury was done
as the grafts have made a good growth this season.

_Pomeroy Seedlings_

This strain of walnuts originated on the farm of Mr. Norman Pomeroy of
Lockport, New York. Trees from this plantation, or seedlings of these
trees, are grown at various places throughout Michigan with the heaviest
concentration near Lexington. There are also a number of Pomeroy
seedlings on the farm of Mr. Grant Fox at Leamington, Ontario. All of
the trees in the Lexington district were more or less severely injured
by killing back of the branches and occasionally by bark splitting or
bark killing. At St. Louis one very fine tree was nearly girdled by bark
injury and will undoubtedly die. Near Ithaca another tree showed
moderate killing back and in the city two trees were killed to the
ground and one other so severely injured as to be useless. The trees at
Leamington, Ontario, were also severely injured, especially those that
bore thin-shelled nuts. Some of the larger trees in this plantation
which bore nuts with moderate thick shells were not as severely injured,
and this would seem to indicate that there may be a relationship between
thickness of shell and resistance to winter cold.

In this plantation it was also found on another occasion that the trees
which bore thin-shelled nuts produced long vigorous succulent shoots
with a large pith and loose, spongy buds. On the other trees that bore
thick-shelled nuts the shoot growth was shorter and firmer than on the
trees with thin-shelled nuts. In contrast to these trees the buds on the
Crath