acre each year. Consequently, the goal is to apply about 2 lbs per 

 acre in each of the 2 applications. For young orchards, the addi- 

 tion of 0.5 lb of Solubor* per 100 gallons (dilute basis) to the 

 first 2 cover sprays meets the B requirement of these trees. Re- 

 ports from New York State indicate that sprays can be concentrated 

 up to 8X with satisfactory results. 



Manganese (Mn): This element was low in 48% of the orchards sam- 

 pled in 1972. In some orchards, deficiency symptoms were evident. 

 (A picture and description of deficiency symptoms of this element 

 appeared in the May-June, 1972, issue of Fruit Notes). 



Research has shown that in its milder stages, Mn deficiency 

 of apple trees does not seem to be accompanied by loss of tree vigor 

 or f rui tf ul ness . However, the condition can be corrected by foliar 

 applications of manganese sulfate or of a fungicide containing Mn. 

 Manganese sulfate is applied about first cover at a rate of 3 lbs 

 per 100 gallons of water. If using an Mn-contai ni ng fungicide, 2 

 or 3 applications are necessary with timings about petal fall, 

 first and second cover. 



Zino (Zn): Based on optimum levels of Zn established by some 

 states, some of our apple orchards are low in this element. We 

 are not convinced that dormant applications of zinc sulfate are 

 worthwhile from the standpoint of increasing tree performance. 

 Until the value of this zinc sulfate spray applied at the "green- 

 tip" stage of bud development can be substantiated, we suggest 

 its use only on a trial basis. 



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



INFLUENCE OF POTASSIUM ON CALCIUM UPTAKE 

 OF 'DELICIOUS' APPLES 



William J. Lord 

 Department of Plant and Soil Sciences 



Since several apple fruit disorders are associated with in- 

 adequate calcium (Ca) in the fruits, growers have been cautioned 

 against excessive use of potassium (K) because this element sup- 

 presses Ca uptake. To help maintain a balance between Ca and K, 

 it has been suggested therefore, that leaf K levels be maintained 

 in the range of 1.25 to 1.50%. However, studies by the late Dr. 

 with a 'Delicious' cultivar indicated that decreased 



K levels far in 



Walter Weeks 



accumulation of Ca in the 

 excess of 1.50% (Table 1) 



'Delicious' cultivar indicated 

 foliage occurred only at 



*Trade Name 



