Size of Blackjon Apple

Abstract

In 1947, Director V. R. Gardner of the Michigan Agricultural Experiment Station corresponded with the author in regard to the fruit size of Blackjon, a color sport of Jonathan. In Michigan, Gardner found the Blackjon to be smaller than Jonathan and other Jonathan color sports. Whether this small size is inherent in the sport or is due to nurseries propagating a small fruited color sport and distributing it as Blackjon is not known. Following the correspondence, the author secured scion wood of Blackjon from eight Illinois growers. (All of the growers had not secured their trees from the nursery that had first distributed the variety). The eight lots along with one lot from the Horticulture Orchard at Urbana, were all top-worked in a single old tree at Urbana. The aim is to bring the scion pieces from the nine sources into fruiting on a single tree and single rootstock so as to better determine if Blackjon from different sources varies in size. To date none of the scion pieces has fruited. This brief statement has been presented in regard to Blackjon to encourage growers who have the variety to observe its size and for a better understanding of the data presented hereafter.