Group 3. Carpathian Walnuts.
This strain of Juglans regia was introduced into Canada by Rev. P. C. Crath of 48 Peterboro Avenue, Toronto, Ontario, from the Carpathian mountains in southeastern Poland. In this part of Europe the winter temperatures are reported to go to -20 degrees F., and occasionally lower. In the winter of 1928-29 a vast amount of injury was done to fruit trees and the less hardy English walnut trees in Poland, but a number of English walnuts came through without serious injury. Scion wood of some hardy selections was sent in 1932 to the writer by Mr. Crath, who was then in Poland. This material was grafted on vigorous growing black walnuts in the spring of 1932 and good results were secured with two varieties. These varieties made a vigorous growth, but notwithstanding this they showed not the slightest injury in the spring of 1934. The growth made during the summer of 1934 has been remarkable and if this unusually vigorous growth survives the coming winter it would seem as though we have an exceptionally hardy strain. The nut characters and productiveness of these varieties have not yet been determined in Michigan, but if they are equal to some of the trees of the same origin, then we will have very valuable trees. These strains have been named Crath and are distinguished by Nos. 2 and 5.
About 100 small seedlings of Polish origin were purchased from Mr. Landega of Toronto, Ontario, an associate of Mr. Crath, and planted at the Kellogg Farm in 1932. These trees have been subjected to trying conditions through drouth, competition with alfalfa, late growth and severe winter temperatures. As a result some have died, but a number are growing nicely, and it is expected that some of these will eventually become established. Seedlings of this lot suffered only slight injury near Sparta, Michigan, but grafts from these same seedling trees set on a vigorous young black walnut were very severely injured. Another tree from this group endured the severe cold at Madison, Wisconsin, during the past winter and made a rapid growth this season.
Scions from another fine tree of Polish origin growing at Mr. Crath's place in Toronto were set on several trees in this state in the spring of 1933 and in every case endured the lowest temperature without much injury to the new growth. A very unusual condition was noted, though on three young black walnut trees top-grafted to scions of this tree. On these trees the vigorous grafts appeared to be uninjured in the wood, but the bark at the point of union on both stock and scion was so severely injured that the grafts died. An examination showed 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 trees Nos. 2 and 5 were short, rather broad and very solid. The wood also was very hard and well matured with a small pith even on vigorous shoots. This seems to indicate that there may be a relationship between density and maturity of wood and buds and winter hardiness.
Other Seedlings
At various places in Michigan there are English walnut trees that originated in England or which are seedlings of trees that came from England. An exceptionally good tree of English origin grows near Ionia and is called Larson after the owner of the farm on which it grew. The Larson tree is at least 50 years old and bears nuts of large size and excellent quality in favorable seasons. This variety was propagated for the college by the Michigan Nut Nursery and some of these trees were planted at the Kellogg Farm in 1933. Unfortunately the past winter killed all the young trees and so severely injured the parent tree that its recovery is doubtful. Beck is another good variety of English origin that grows near Allegan on the Monterey road. The original tree of this variety was very severely injured and much greater injury was noted on seven-year-old grafts of this variety which had been set on a black walnut. At Vassar there is a tree of English origin that yields very fine nuts, but this one was also severely injured. Near Conklin there is an old tree of German origin and this was likewise severely injured, but not so much as the trees from England.