Colby, a Hardy Persian Walnut for the Central States
J. C. McDaniel, Extension Horticulturist, University of Illinois
When the Reverend Paul C. Crath of Toronto imported walnut seeds and scions from his native Ukraine region and adjacent areas of Poland in the 1920s, he started a chain of propagation and selection which promises to establish the Persian walnut (Juglans regia) as a commonly grown nut in southern Ontario and the north central states. The best of his importations, and seedlings from them, are fruiting in such states as Wisconsin, Iowa, Illinois and Missouri, showing in many cases a degree of hardiness which must reverse the conclusion of an older generation of pomologists that Persian or "English" walnuts were too tender for successful cultivation in most of the middle west.
The time has now arrived when there are enough fruiting trees of the "Crath Carpathian" walnut seedlings in many states that comparisons can be made and the more promising ones named and disseminated for propagation. The nuts which the Reverend Mr. Crath imported in greatest quantity during the middle 1930s came from more than 100 different seedling trees selected in Poland. Their seedlings exhibit much variability in characters of trees and nuts. Some are much less hardy than others under our conditions. Not all are as large fruited as their seed parents (and some of the parent trees bore small nuts). Though many have smoother shells than Mayette or Franquette, there is also much variation in shape, thickness, and color of shells. Color and flavor of kernel vary from tree to tree. The season of nut maturity, though variable, is generally early enough in locations where the trees are winter hardy. The parents were selected for good filling of kernels, and this character generally has carried over to the seedlings fruited in America. As with other walnuts, some of the Carpathian seedlings are apparently more susceptible than others to fruit damage by the husk maggot. Walnut blight has infected them in some localities.
The COLBY Persian walnut, named in August 1951, and released to nut nurserymen for propagation early in 1952, is the best to date of thirteen Carpathian seedlings (each from a different parent tree) planted at the University of Illinois Agricultural Experiment Station from 1937 to 1939. It is the first Persian walnut variety to be named at this station.
The name, Colby, honors Dr. Arthur S. Colby of the Department of Horticulture at the University of Illinois, who has been in charge of nut investigations here since 1919. It was given to this variety, with his permission, by members of the Northern Nut Growers Association during their 42nd Annual Meeting, held at Urbana in August, 1951. Dr. Colby is a former president of the Northern Nut Growers Association.
Colby is a seedling of the tree designated as Crath No. 10. The seed was collected in 1934 from the parent tree near Cosseev, in the Carpathian mountain region of southern Poland as then constituted, planted in the nursery of S. H. Graham, Ithaca, New York, and the seedling transplanted to Urbana, Illinois at the age of two years. It has been fruiting annually here since 1942, with crops of up to 1-1/4 bushels in recent years. The accompanying cut shows nuts of the 1951 crop, a little less than 2/3 natural size. They are thin shelled, like the parent Crath No. 10, well filled with kernels of rich flavor, and are medium in size for varieties of this species.
