32 N. J. Agricultural Experiment Stations Bulletin 356 



the attachment of the stem, which only permitted a small supply of 

 plant-food to reach the fruit instead of an extra large quantity, as in 

 the case of the very large fruits. Further investigations may show 

 that this is correlated with defective pollination as suggested 

 previously on page 18. 



Fig. 20 — Two Normally Colored Belle of Georgia Peaches on 

 Either Side of One Kept Covered With a Black Paper Bag 



Factors Which Determine Color of Healthy Fruit 



The normal red coloring on peaches is the result of maturity and 

 exposure to sunlight, with temperature as a possible factor, as illus- 

 trated in figure 20. Abnormal colorings of various sorts may appear 

 on the fruits at various times. Where the foliage is severely burned 

 by sprays, the red colorings may become purplish in appearance, and 

 even where no spray burning actually occurs sulfur sprays often irri- 

 tate the skin of the small green fruits so that purplish or abnormal 

 colorings result. In seasons when winter injuries occur to the wood 

 of the twigs and branches, so as to produce enlarged fruits, all sorts 

 of injuries, such as limb scratches and curculio stings, may result in 

 unusual color markings, probably because of the increased sugar con- 

 tent. In addition to such markings, many fruits developed blotches of 

 red color practically identical with yellows in the Vineland orchards 

 during the season of 1913. 



