14 



BITTER PIT INVESTIGATION. 



far advanced, it may present the appearance of pimples rather than dimples, and this is easily 

 explained. The shrinking of the tissue beneath the skin in isolated patches causes pit-like 

 depressions, but when the patches become continuous, the wave of depression has a corresponding 

 elevation, and, when it extends over a considerable area, then it is thrown into folds and 

 wrinkles. 



An examination of a large number of affected trees in different districts showed that it is 

 not confined to one side of the tree, but occurs all round it ; that it may occur equally in those 

 fruits exposed to the sun and those in the shade, that the topmost boughs may bear apples free from 

 it or they may be affected ; and there is every gradation to be found, even on the same tree, of pit, 

 pit and crinkle combined, and crinkle alone. 



It may be found associated with other diseases, such as " water core " or " glassiness," and 

 during the past season sun burn or heat scald has frequently accompanied it. So much has this 

 been the case that the disease has been attributed to that cause, although, that the two are distinct, 

 may be seen occasionally when one side of an apple is affected with sunburn and the opposite with 

 crinkle. An apple affected with crinkle is an easier prey to excessive heat than a sound one, and 

 in every case of crinkle the skin is unaffected, whereas in sunburn, acting from the outside, the 

 skin suffers. It only remains to add that when the brown tissue of crinkle is kept 

 in the mouth for some time there is a decided bitter taste. In Tasmania, the disease 

 is usually called " Pig-face," because it disfigures and gives a peculiar appearance to the 

 crown end of the apple when badly developed, and a grower referred to the affected apples as 

 u tuberculous " from the pimpled nature of the surface. It is, likewise, sometimes called 

 " Monkey-face." 



It also occurs in Five Crown apples in New South Wales, and, although known in certain 

 districts for many years, the disease has never caused much loss. 



The varieties in which it has actually been found in Victoria this season are— Five Crown or 

 London Pippin, Newton Wonder, Blenheim Pippin, Stone Pippin, Annie Elizabeth, Jonathan, 

 Statesman, and Baldwin. In South Australia it occurred in Five Crown, Rome Beauty, and 

 Dunn's Seedling or Munroe's Favourite. As throwing light on the conditions under—which this 

 form of Bitter Pit occurs, I will give two illustrative examples. At Burnley Gardens, immediately 

 after the fruit had set on an Annie Elizabeth apple-tree, a number of clusters were tied up in white 

 calico bags to see the effect on the development of Bitter Pit (Fig. Ill), but, on removing the fruit 

 early in March, a little crinkle was found, five crinkled apples being in the bags, and only one of the 

 apples exposed on the tree affected. There was this peculiarity about those occurring in the bags : 

 that, while crinkle was very pronounced, dark-green depressions characteristic of Bitter Pit were 

 associated with it, and sometimes found overlying it. Here both " pit " and " crinkle " had developed 

 m the same apple, and, on making a section, the continuous brown tissue as well as the isolated 

 patches were seen. Exposed apples also showed pit and crinkle combined, but it was very noticeable 

 in the apples enclosed in the bags. 



It may also be noted that, although the apples were protected to a certain extent from the 

 effects o£ the sun's heat by the white bags, nevertheless a larger proportion were affected with 

 crinkle than those exposed on the trees. 



In an orchard at Healesville, Victoria, " Crinkle " was very bad this season, while last season 

 it was not noticed. The variety was Five Crown or London Pippin, the trees were from 15 to 25 

 years old, and out of 2,000 cases of fruit, less than 1,000 were sound. This loss was entirely due 

 to "Crinkle," and it was first observed on 19th January. Afterwards it developed very rapidly 

 and in about a fortnight it was quite general. In the same orchard there was a luxuriant crop of 

 Jonathans, but not a trace of Crinkle could be seen on any of them. The conditions otherwise 

 being equal, there was evidently something in the constitution of the Five Crown apples which 

 rendered them peculiarly susceptible to this disease. 



