20 BULLETIN 1104, U. S. DEPARTMENT OF AGRICULTURE. 



Direct evidence on this question is furnished by the very decisive 

 results of thinning the fruit and girdling branches during the 

 summer of 1919. The trees were bearing a heavy crop, and brown- 

 ing was almost negligible in normal fruit during the following 

 winter storage season. Very considerable browning, however, ap- 

 peared in the large well-nourished fruit from the girdled branches, 

 whereas even less than the average appeared in fruit from branches 

 from which half the leaves had been stripped. 



"With these facts in mind, before picking in 1920 and again at the 

 time of picking, careful notes were made concerning the density and 

 condition of the foliage on the trees, the size of the crop, and the 

 size of the fruit. The crop in the orchard was light during the 

 1920-21 season, so the fruits as a rule were of very large size. Indi- 

 vidual yields varied from practically no fruit to 6 or 8 boxes per 

 tree. Since most of the trees under observation were very large, 

 even a crop of 8 boxes was not more than an average yield for a 

 normal year. 



The foliage on the different trees varied widely in density and 

 appearance. The size of the fruit varied with the size of the crop' 

 and the density and condition of the foliage. When the crop was 

 small and the foliage was in good condition, the fruit was usually of 

 large size. 



Upon comparing these records with the percentages of browning 

 that developed during the storage season, it was found that trees 

 with the combination of good, rich foliage and a small crop of large- 

 sized fruit have practically always produced fruit that tended to 

 brown very badly. On the other hand, fruit from trees with a large 

 crop of medium-sized apples has almost invariably developed very 

 little browning. Trees possessing very poor foliage and also bear- 

 ing a very light crop were often difficult to place so far as brown- 

 ing was concerned. Fruit from such trees usually developed moder- 

 ate browning. 



This relationship of the total crop on the tree to the occurrence 

 of browning may be shown by a study of the trees in the nitrogen 

 plat. Records on the fruit from trees of this plat, together with 

 notes made at the time of picking in 1920, are presented in Table 7. 



It is impossible to predict accurately from such data as the notes 

 on tree conditions presented in Table 7 how much internal brown- 

 ing will develop during the storage season. It is of interest, how- 

 ever, that all the trees in the nitrogen plat which produced a high 

 percentage of sound fruit are those producing a fairly large crop 

 of medium-sized fruit. Nos. 133, 134, 137, and 138 were all well 

 loaded for trees of their size. Trees Nos. 46, 132, and 136, fruit 

 from which became particularly badly browned!, had very light 

 crops of large-sized fruit and excellent foliage. 



