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Mn deficiency may be associated with low or deficient levels 

 of K under orchard conditions. In addition, the use of herbicides 

 has been shown to reduce manganese levels, possibly because of 

 increased soil temperatures. 



Copper (Cu) deficiency in the Fast is usually associated with 

 high soil pH (6.3+) and/or soils that are inherently low in Cu , 

 i.e. coarse glacial tills and sands or gravels. Fixed Cu fungi- 

 cides such as Tribasic Copper Sulfate or C.O.C.S. applied at 

 green-tip to 1/4-inch green at rates of 2 to 4 lbs. per 100 gallons 

 dilute rate are effective in supplying Cu to apple trees. These 

 sprays are suggested for trial on apples and pears when leaf 

 samples contain less than 5 ppm of Cu. The higher rate is usually 

 required to overcome Cu deficiency (leaf samples containing 3.5 

 ppm or less copper) . DO NOT apply Cu sprays after flower buds are 

 exposed. 



The foliage of peaches is highly sensitive to copper sprays. 

 Low rates of Cu sulfate (1/2 lb. per 100 gallons dilute rate) have 

 been reported to be effective in supplying Cu to prunes and plums 

 and to be somewhat effective in reducing cracking in sweet cherries 

 when applied as foliar sprays. Further work is needed to determine 

 safe corrective treatments for use on stone fruits. 



Summary 



Nutrient sprays represent a means for immediate applications'-- 

 of an element to the foliage and fruiting surfaces of fruit trees. 

 In most cases, these sprays should be considered as supplemental 

 treatments for adjusting nutrient status rather than as the sole 

 means of supplying the element in question. Zn sprays, however, 

 represent the most efficient and effective means of supplying this 

 element because of numerous problems involved in obtaining adequate 

 response to soil applications of Zn. 



Frequently, multi-element imbalances are encountered that 

 present difficulties in correctly identifying the critical problem. 

 In cases involving reduced growth, lack of normal dilution may 

 interfere with identification of nutrient deficiencies. Visual 

 evaluations of factors such as vigor of shoot growth, leaf size, 

 crop level, and fruit development should be used to supplement 

 leaf analysis in diagnosing the need for additional amounts of a 

 particular element or elements. 



