Tabi e 1 . The effects of various treatments on the foliar calcium 

 content of 'Baldwin' apples. 



Treatment 

 number 



Treatment 

 description 



Leaf calcium (%) change 

 (1970-71 minus 1968-69) 



1 



2 



3 

 4 

 5 

 6 



Calcium nitrate, foliar 

 (5 lbs/100 gals, 6 times 

 annual ly) 



Soil liming 



(100 lbs/tree annually) 



Calcium nitrate, foliar, 

 plus soil 1 imi ng 



Soil calcium nitrate 

 (7 1 bs/tree annual ly) 



Soil calcium nitrate plus 

 foliar calcium nitrate 



Calcium hydroxide plus 

 magnesium hydroxide slurry, 

 soil injection April, 1969 



+0.212 



+0.094 

 +0.231 

 +0.073 

 +0.201 

 +0.103 



In October, 1971, the second year of the experiment, one box 

 fruit was picked from each tree and scored for the occurrence 

 bitter pit. These fruit were then stored until late March at 

 32 F, when they were removed from storage and again scored for bit- 

 ter pit occurrence. After an additional 5 days at 70 F, the pres- 

 ence of scald, internal breakdown, and decay was recorded. 



of 

 of. 



Early in October, 1971, a separate set of fruit samples was 

 taken from 11 trees known to be relatively low in calcium content, 

 and from 8 trees known to be relatively high in calcium content. 

 These apples were stored at 32 F until Janui 



lary, when they were re- 

 moved from storage and their respiration rate during 9 days at 70 F 

 was determined. 



Although it is still too early in the experiment to 

 uate treatment effects, certain trends are seen in this 

 sul ts . 



fully eval 

 year's re- 



in Table 1, the effects of the treatments to date on the leaf 

 calcium content are shown. The greatest increases in calcium have 

 resulted from foliar applications, either alone (Treatment 1} or 

 in combination with soil applications (Treatments 3 and 5). Soil 

 applications, whether employing lime (Treatment 2), calcium nitrate 

 (Treatment 4), or an injected calcium hydroxide plus magnesium hy- 

 droxide slurry (Treatment 6), have been considerably less effective, 



