3 - 



or fall, but N fertilizer should be applied in the spring about 2 

 or 3 weeks before bloom. 



Suggested Rates of Fertilizer for Bearing Peach Trees 



Approximate amounts per tree (lbs) 



Ammonium nitrate Muriate of potash 



Tree age or its equivalent or its equivalent 



3-6 1/2 - 1 1-2 



6-9 1 - 1-1/2 2 - 3 



9 - 12 1-1/2 - 2 3-4 



12 and over 2-4 4-8 



*************** 



RESEARCH FROM OTHER AREAS 



Mack Drake 

 Department of Plant and Soil Sciences 



Calcium distribution in 'Merton' apple fruits . A paper entitled 

 "Longitudinal Distribution of Applied Calcium and of Naturally 

 Occurring Calcium, Magnesium, and Potassium in 'Merton' Apple 

 Fruits," which appeared in the Australia Journal of Agricultural 

 Research , Volume 24, 1973, by T. L. Lewis and D. Martin, contains 

 several pertinent findings concerning calcium (Ca) in apple fruit. 



These workers showed that the Ca concentration in the 'Merton' 

 fruits declined from the stem end to the calyx end, which may ex- 

 plain w^^y bitter pit lesions generally are more prevalent near the 

 blossom end of apples. On the other hand, Mg concentration increased 

 toward the calyx end to about 8 times the Ca concentration. The 

 authors proposed that if the Ca level in the calyx end of fruits 

 were to fall below the critical level, the concentration of Mg 

 would be high enough to replace Ca within the cells of the apples. 



This replacement may have adverse effects on the cells and 

 cause bitter pit lesions to develop. This emphasizes the impor- 

 tance of maintaining other nutrients in balance with Ca . 



To find out why Ca sprays are more effective than soil appli- 

 cations in increasing fruit Ca, Lewis and Martin injected radio- 

 actively labeled calcium chloride s-olution into a fruiting branch 

 of a 'Merton'- tree 8 weeks prior to harvest. Only very small 

 amounts reached the calyx end of the mature fruits. Leaves and 

 buds on the injected branch accumulated 95% of the recoverable Ca, 

 and the fruits accumulated the remaining 51 of which only about 1% 

 was in the calyx end. This illustrates why it is difficult to in- 



