Cork Spot (York Spot) 
The term cork spot has been proposed by a committee from the Cumberland- 
Shenandoah Fruit Worker's Conference to replace the term York spot. The condi- 
tion widely known as York spot is probably as old as the York Imperial apple, 
and the term has been in the literature since 1915. 2 
The need for a change in name stemmed from several sources: (1) A 
certain amount of confusion was attached to the term York spot, due in part to 
the poor original description and in part to the view held by some that York 
spot is the same as bitter pit; (2) recent research has shown that the occur- 
rence of York spot has been reduced on York Imperial apples by timely boron 
sprays, but not by calcium sprays, whereas bitter pit was reduced on susceptible 
varieties by calcium sprays, but not boron sprays; and (3) a condition similar 
to York spot has been found on certain other varieties, thus impairing the 
usefulness of a varietal name for the disorder. 
Cork spot (York spot) is most prevalent on York Imperial apples, a vari- 
ety grown mostly in Virginia, West Virginia, Maryland, and Pennsylvania. At 
times a similar disorder occurs also in the same locality on Delicious, Golden 
Delicious, Stayman, Grimes Golden, and Jonathan. No research has been published 
on the disorder on these varieties, however. The varieties listed as being 
subject to cork spot are also subject to ordinary bitter pit and develop typical 
symptoms. 
Cork spot like bitter pit is induced by soil moisture stress, which 
creates a complex disturbance in the nutritional balance. Until research proves 
cork spot and bitter pit to be the same disorder, it seems best to consider 
them separately because of the difference in the symptoms and responses of the 
disorders to treatment. 
Cork spot develops entirely in the orchard during the growing season and 
the external appearance does not develop or change after harvest. The first 
symptoms show as slightly flattened areas that appear somewhat water-soaked due 
to the tissues being greener or more purple than normal depending on the color 
of Eher£ruit's’. 
Reed and Crabill 2/ noted the appearance of the spots first during 
August. Some think that they appear earlier. Seriously affected fruits become 
somewhat distorted as they grow. If a fruit has a single spot or a few scat- 
tered spots, the external appearance is that of one or more flat-bottom or 
dimple-like pits. Sometimes a single pit is centered around a lenticel that is 
enlarged and prominent. In the past this symptom was perhaps mistaken for the 
feeding puncture of a sucking insect, and the condition was often identified as 
stigmonose. Since stigmonose seems to have lost its original application the 
term now appears to have little or no usefulness. Cork spot can appear anywhere 
on the fruit and the skin in the pits usually does not turn brown or black. 
Pits have brown corky areas either below the affected peel or somewhat deeper. 
In seriously affected York Imperial apples, corkey tissues occur in relatively 
large areas up to one-fourth inch in diameter or somewhat larger and may be 
located near the surface or half way to the core. 
Published data concerning cork spot are somewhat. limited. In 1959 Dunlap 
and Thompson (46) published results of a study, entitled "Effect of Boron Sprays 
9/ Reed, Howard S., and Crabill, C. H. The York Spot. Va. Agr. Expt. 
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