- 6 



use of this compound until more information can be obtained concern- 

 ing safeness of calcium chloride from the standpoint of leaf injury. 

 Apply the calcium chloride sprays as separate applications. Use 2 

 lbs of calcium chloride per 100 gallons of water beginning 2 weeks 

 after petal fall, because research indicates that cork spot deform- 

 ations arise in the first 30 days of fruit development. Repeat the 

 calcium chloride sprays at 2 or 3 week intervals, totaling 3-5 ap- 

 plications. Where bitter pit is the only problem, the first appli- 

 cation can be delayed until July. 



Until more experience is obtained concerning calcium chloride 

 sprays, we will continue to suggest calcium nitrate. The timing of 

 the sprays is the same as for calcium chloride. Calcium nitrate 

 (fertilizer of technical grade) is used at the rate of 5 lbs per 

 100 gallons of water. A spreading agent, such as Triton B, should 

 be added to the calcium nitrate spray at the rate of 3 fluid ounces 

 per 100 gallons of water. 



Magnesium (Mg) : Most leaf 

 higher) in 1973. The Mg r 

 maintaining an adequate do 

 several years before lime 

 Epsom salt sprays can be u 

 ply 2 or 3 sprays at the r 

 at the time of calyx, firs 

 avoid possible incompatibi 

 be combined with the regul 

 salts or a lime high in Mg 



samples had 

 equirements 

 lomitic limi 

 is effective 

 sed to help 

 ate of 15-20 

 t cover and 

 lities, the 

 ar pesticide 



unless leaf 



suff i 

 of tre 

 ng pro 



in CO 

 correc 



lbs p 

 second 

 Epsom 



spray 



sampl 



cient Mg (o.25% or 

 es can best be met by 

 gram. Since it takes _ 

 rrecting Mg deficiency, 

 t the condition. Ap- 

 er 100 gallons of water 



cover sprays. To 

 salt sprays should not 

 s . Don't apply Epsom 

 es or visual observa- 



tion indicate need because Mg can suppress Ca~ 



Boron (B) : B was generally low in the leaf samples obtained in 

 1973. B can be supplied to apple trees either by foliar or soil 

 applications. Use the most economical and convenient method. 



Soil applications of B should be applied to orchards every 3 

 years. Borax is the common material used. The rates of applica- 

 tion per tree vary with age and size. Apply 0.25 lb of fertilizer 

 borate (20.2% B) or its equivalent to young trees, 0.5-0.75 lb to 

 medium age and size trees, and 0.75 - i.o lb to large or mature trees 

 If the soil application of B is followed by a wet spring and summer, 

 it may be advisable to apply 2 foliar applications of B the follow- 

 ing year. 



Many growers rely on annual foliar applications of B. The 

 usual practice is to add Solubor* to the first 2 cover sprays. 

 Fertilizer grades of borax may contain grit and should not be used 

 in a sprayer. Mature trees should receive 4 lbs of Solubor* per 

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

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

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

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



*Trade name 



