70 



BITTER PIT INVESTIGATION. 



While the apple was growing and receiving the necessary nutrient fluid to enable it to grow, 

 there would, under these conditions, be excessive transpiration, and this excessive transpiration 

 would be associated with rapid growth. 



In this case, the continued heat and accompanying drought began to prevent supplies reaching 

 the peripheral network of vessels when the fruit was approaching maturity, and the consequence 

 was collapse of the cells and subsequent browning and toughening. 



All the conditions encouraging excessive transpiration are here, such as bright sunlight, a 

 dry atmosphere, and a high temperature, and the porous soil would ultimately become too dry to 

 keep up the supply, more water being given off at the surface than taken in by the roots. 



[t will be seen, therefore, that Bitter Pit may arise under different weather conditions, and 

 may be brought about by the co-operation of different factors. The weather may be regular and 

 steady in a direction which encourages excessive transpiration, or it may be fluctuating, and a dry 

 spell suddenly followed by showery weather, at a season when the apple is approaching maturity 

 and most rapidly growing, may prevent the regular expansion of the vascular network. The final 

 result is the same, the collapse of patches of cells owing to the failure of their water supply. 



The severity of the attack is shown by a, correspondent in the Journal of the Royal Horticultural 

 Society, London, March, L912, in which it is stated that "This disease has been very prevalent 

 <luring the past year, not only in soft-fleshed varieties, in which it always occurs more or less, but 

 also in the hard-fleshed ones, (hough bo a less extent." 



ORIGIN OF "CRINKLE." 



The question is sometimes asked, " Why should the Bitter Pit only appear in spots, and 

 not al] over ? " Well, I consider thai in the case of Crinkle or Confluent Bitter Pit it does appear 

 all over, and the explanation of how it occurs will throw light on the question. We have already 

 seen that Bitter Pit may occur either when there is an excess or deficiency of moisture at a critical 

 period of growth. When there is excessive moisture, and the enlargement of the pulp cells is too 

 rapid to allow the vascular net to be formed regularly, then, wherever the supplies fail, the cells will 

 ultimately collapse and die, But when there is insufficient moisture to enable the conducting 

 tissue bo supply all the cells towards the periphery, then a similar result will follow. 



Now, in the case of Crinkle, the browning and toughening of the cells is produced over a large 

 area., just beneath the skin, and the large and numerous cavities formed, with the consequent folding 

 and depression of the skin, are indications of the sudden failure of supplies after a rapid rush of growth. 



Finally, it is evident from this view of the origin of Bitter Pit, that the disease is not confined 

 to one country, but probably exists wherever the apple is grown, and that it dates back to a very 

 early period in its history. Even in Victoria, where apple trees have only been grown for about 

 7<> years, the disease was known 35 years ago under the name of "Measles," and sometimes 

 of "Small-pox" of the apple, and in South Australia, where there are some Cleopatras over 

 50 years of age, it has been known since 1868. In the older countries of the world, it has also long 

 been known, although at first without a definite name to distinguish it, and I am indebted to Mr 

 John Osborne, of Tasmania, for the following reference dating back to the twelfth century:— 

 Richard Neokham, a, prolific writer, who nourished about the middle of the twelfth century, 

 mentions what was then called fck a, serious disorder of ye apple which is like unto a blister drying 

 up under ye skin and givith ye fruit a taste that is bitter and unwholesome to the palate" — a 

 condition much akin to the Hitter Bit of the present day. 



CONTRIBUTING FACTORS. 

 The scientist and intelligent orehardist alike have come to the general conclusion that " it has 

 something to do with the sap," although that very enigmatic statement may be interpreted in a 

 variety of ways, li must never be forgotten that our fruit trees are grown under artificial conditions, 



