Colby walnuts of 1951 crop, showing thin shells and plump, sige emele 
As indicated above, there is a wide variation in Persian walnut hardiness, even 
among seedlings from the Carpathian Mountains, which are among the coldest regions 
in the world that produce edible walnuts of satisfactory size and cracking quality. The 
seedlings, like other nut seedlings, vary also in other ways -- in disease resistance, vigor 
and productiveness of tree, and in size, color, flavor and season of maturity of the nuts. 
It is because of this variability that walnut experimenters, private individuals as well 
as station workers, are still interested in growing walnut seedlings, hoping to get some- 
thing superior for their needs and the local conditions, through a recombination of the 
genes found in the parent varieties. A few of the very best seedlings of Colby and other 
newly selected Carpathian walnut varieties, it can be expected, may expand the limits 
of adaptation and usefulness that are set for the older varieties. Somewhat inferior 
seedlings, unfortunately, usually outnumber superior ones by a wide margin. The 
beginning grower who grafts his own young black walnut trees with scions of an adapted 
variety, or gets trees grafted by a reliable propagator, can be assured a better chance of 
a successful outcome than if he raised seedlings, even from the most choice Carpathian 
nuts available. The quickest results, and the most permanent trees in areas where 
Persian walnuts are of borderline hardiness, can be expected from topworking high on 
trunks of native black walnut, using grafting or budding methods which have been 
locally successful for walnuts. 
One other Carpathian walnut in the Urbana planting, R5 T27 (a seedling of Crath 
No. 23) is as hardy as the Colby, and, although it has so far been much less fruitful, 
supplies abundant pollen at the right time to pollinate the Colby. Both Colby and 
R5 T27 often start shedding pollen before their pistillate flowers are receptive. Flower- 
ing a few days later than the Colby, the R5 T27 tree supplies pollen after most of the 
Colby catkins are through shedding. While the Colby flowering is such that it should 
be partially self-fruitful, there are years when slightly later pollen from such a compan- 
ion variety should be distinctly beneficial. 
Several nut tree nurseries which have started it’s propagation, will have Colby 
walnut trees for sale in the fall of 1953. Seionwood of Colby and the R5 T27 pollenizer 
walnut will be available in limited quantity from the station. Because it is scarce, 
mie preference in distribution of the UA mal be oe to oe RN haye-ha | some. 
previous success in nut free-tred 
TS Nee wi MI Wey & Selcy Wernat oe Yall 
WA Vcly oqo Ye \ Wu RSIS Y 
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