THE OLIVE 125 



tissues and of the regenerating zone has the same effect that the 

 puncture of an insect would, and at times j^roduces the enlargement 

 of the zone and sometimes the enlaro^ement of the herbaceous tis- 

 sues. These enlargements in time extend to the wood under the 

 bark and cause the bark to draw away thus affording a receptacle 

 for different insects. This would however be an effect and not a 

 cause of the evil. 



Some orchardists remove the protuberances by shaving them off 

 with a sharp knife, but this does not restore the tree to health as this 

 cutting does not remove the primary cause. The first method for 

 its cure is to keep the trees wide apart, well lighted, to prune spar- 

 ingly, and to abolish the barbarous usance of beating the trees when 

 gathering the berries. 



Senor Tablada says he found an insect eight hundredths of an inch 

 in length in the act of making these warts and cured the tree by cut- 

 ting them off. 



.THE OLIVE ROT. 



{See Plate XVI.) 



The rot is the gangrene which appears on the trunk and larger 

 branches of the olive tree. At times it is so extensive as to con- 

 sume nearly all the cylindrical part of the wood leaving the larger 

 branches hollow and rendering them an easy prey to the action of 

 the winds. 



When a wound is made on the olive tree either bv the breakins: 

 of a limb or by pruning, and is not at once shielded from contact 

 with the air, a process of canker is initiated, provoked by the hu- 

 midity found there, the action of insects and the spores of certain 

 lichens or creepers. Trees improperly pruned are usually the ones 

 attacked by the rot. To prevent it, an olive orchard should be 

 placed on well drained soil and receive plenty of light. The trees 

 should not be bruised and wdien a branch is cut off the wound 

 should be immediately covered with grafting wax or a mixture of 

 cow dung and clay. When the rot has taken hold the diseased part 



