THE LIME-MAGNESIA RATIO 105 



lime to magnesia which varied from 0.9: 1 to 3:1, with many 

 intermediary values, while ratios on soils in which chlorotic trees 

 were found varied from 1.7: 1 to 4: 1. The worst tree encoun- 

 tered was found growing on a soil in which the ratio was 1: 1.7. 

 This, it will be noted, is an intermediate value in the first group 

 of ratios above referred to. These data, therefore, would lend 

 but little support to the necessity of a certain lime-magnesia 

 ratio for citrus trees. They do not of course exclude the possi- 

 bility that, were the immediate cause of chlorosis removed, the 

 Hme and magnesia ratio as a factor in growth and production 

 might come to the fore in a more important way, but at any 

 rate, they furnish no evidence at the present time in support of 

 such a view. 



{To he concluded in May issue.) 



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