272 CACAO 



the Board of Agriculture of England published some little 

 time since an account of investigations into the " Effect 

 of Copper Solution on Plants," on which a note appeared 

 in the Bulletin of the Trinidad Botanical Department as 

 follows : 



" This chemical is largely used as a fungicide, and some 

 of its solutions must necessarily be absorbed by the soil 

 when spraying operations are performed. That this 

 operation should be done with great care appears strictly 

 necessary owing to the effect of this chemical upon the 

 roots." Herr Richard Schander says : " The effect on 

 plants of the copper left in the soil by spraying can never 

 be beneficial, and in any case the effect must become 

 apparent much later than the application of the solution, 

 as it would be absorbed by the soil." 



The author considers it proved that copper is injurious, 

 and that plants can only absorb a very small quantity 

 without injury. It follows, therefore, that plants growing 

 on ground on which copper sulphate has been cast will be 

 naturally weaker, and thus suffer more from a following 

 attack, insects or fungi, than land free from copper. 



It may be pointed out that some persons quite disregard 

 the poisonous character of cupric sulphate, and have even 

 recommended that it should be applied to the roots of the 

 cane, in order to render them fungus proof ; but of late 

 little has been heard of this proposal. 



It has also been argued that because " Bordeaux 

 mixture" is largely used in vineyards, it does no harm 

 to the vine or to other plants to which it is applied. 

 This assumption is often made, it is feared, because the 

 resulting damage is not at once apparent after application ; 

 or, when it does appear, is attributed to other causes than 

 the action of copper sulphate. Some of the sprays used 

 for destruction of insect pests are, however, quite harmless 

 in their character, and can be used with great freedom 

 and without danger. 



The methods of spraying have become somewhat of a 

 craze of recent years, and some cultivators go to unr^asga- 



