A. THE TREE AND FRUIT 



Factor 



1. Variety 



2. Sport 



3. Rootstock 



4. Root injury 



5. Young trees 



6. Vigorous trees 



7. Light crops 



8. Off-year-crop 



9. High leaf/fruit ratio 



10. Defoliation 



11. Injured foliage 



12. Larger fruit 



13. Russeted fruit 



14. Side fruits in cluster 



Bitter Pit 



effects severity 



may be influenced 



may be influenced 



i ncreased 



i ncreased 



i ncreased 



increased 



i ncreased 



i ncreased 



decreased 



decreased 



i ncreased 



decreased 



i ncreased 



B. THE WEATHER AND ATMOSPHERE 



Factor 



1. Late rainfall 



2. Fluctuating moisture 



3. Low relative humidity 



4. High temperatures 



5. Excessive transpiration 



6. Ultraviolet rays 



7. Air pollution 



Bitter Pit 

 i ncreased 

 i ncreased? 

 i ncreased? 

 i ncreased? 

 i ncreased 

 ? 



? 



CULTURAL PRACTICES 



Factor 



1. Heavy pruning 



2. Summer pruning 



3. Fruit thinning 



4. Delayed thinning 



5 . Ringing 



6. Late irrigation 



7. Overt re e sprinklers 



Bi tter Pit 



1 ncreased 



decreased 



i ncreased 



less increase 



i ncreased 



i ncreased 



may be decreased 



D. SOIL AND NUTRITION 



Factor 



1. Wet or dry soil 



2. Low pH 



3. Adequate 1 ime 



4. Low calcium (Ca) 



5. Excess N 



6. High N/Ca 



7. High K or K/Ca 



8. High Mg or Mg/Ca 



9. High P 



Bitter Pit 

 i ncreased 

 increased 

 may decrease 

 i ncreased 

 i ncreased 

 increased 

 i ncreased 

 i ncreased 

 increased? 



