n: Size of crop in proportion to size of tree

1947 1948 1949 1950

Percentage of unfilled nuts:
1947 1948 1949 1950
R*H
--------------------crop
pounds

* R = 1/2 limb spread.
* H = height; lowest branch to top.

In addition to these data, photographs, both in black and white, and in
color, were taken of the trees and often of the surroundings, and a map
made so that the trees can be located in the future by any one wishing
to do so.

For examination by any one wishing to do so, there are on the
secretary's desk copies of the case histories, as written up, of the
first and second prize winners, the Duke and the Burson.

A careful study of these ten trees has not revealed any single factor
that can be pointed to as essential to the production of a superior
walnut variety. They were found on good and on poor soils, on good and
poor sites, in soils of a wide range of pH values from very acid to
alkaline in reaction. Most of the trees were located in the southern
part of the state at 39 deg. to 40 deg. North Latitude, but it is hard to
imagine that the latitude has any specific effect on the superior
qualities of the nuts.

In all cases where the trees were now standing in impoverished soils,
low in humus, fertility, and in pH value, it was quite evident that the
soil was probably in far better condition when the trees got their start
fifty to a hundred or more years ago.

+Winter Killing 1947-1948+

In 1947 scions of six of these prize winning trees were successfully
grafted into established ten year old black walnut seedling trees at the
Mahoning County Experiment Farm at Canfield, Ohio, location 41 deg. north
latitude. The scions grew nicely in 1947 but all were winter killed
during the winter of 1947-1948 with the exception of one scion of Kuhn
and one of Davidson. Two scions of Duke, two of Kuhn, one of Athens, one
of Orth, seven of Jackson perished during the first winter after
grafting. This severe killing of 1947-48 apparently indicates that
winter injury to these varieties may be expected some years when they
are planted under conditions similar to those at the Mahoning County
Experiment Farm. The one scion of the Davidson variety came through in
fine shape, so this would be the exception.

The winter of 1947-48 was unusual in the severity of the winter injury
to the black w