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by grafting on to this hardy stock they have beeu able to immunise their 

 more delicate and valuable varieties. In Ceylon we have the strongest 

 evidence that certain varieties of the tea plant (especially the Assam 

 indigenous stock) are most markedly free from injury by the so-called 

 ' mosquito blight ' (Helopeltis). In any serious epidemic that may 

 threaten the profitable cultivation of an economic plant we should at 

 once be on the look out for any accidental varieties or strains that may 

 prove resistant to that particular disease. In cases where the hardier 

 stock is not otherwise so profitable as the more delicate variety, by 

 grafting upon it a more valuable scion the latter may sometimes be 

 rendered equally immune. 



Curative Measures. 



Where preventive measures have failed, as even with the greatest 

 care — must often happen, recourse must be had to curative measures. 



In no single connexion can the old proverb, ' A stitch in time saves 

 nine,' be more aptly applied than in dealing with insect pests. In this 

 case the ' stitch in time' is more likely to save ninety, or nine hundred, 

 or nine thousand ! 



If a pest is to be eradicated, immediate treatment is the most im- 

 portant part of the process. 



And the first step towards treatment should, when possible, be the 

 isolation of the infected area. All ordinary work amongst the affected 

 trees should be deferred until alter treatment. The young larvae of 

 scale-insects are very minute and active, and one of the most fertile 

 sources of their distribution is by means of clothing. 



Another important point is that the treatment should be applied on 

 the spot. If the infected branches are cut down and carried off to some 

 other part to be burned, they may be shedding the germs of the disease 

 all along the way. 



It is difficult to lay down hard-and-fast rules for action, so much 

 depends upon circumstances, e.g. the nature of the particular pest, its 

 extent, the nature and value of the plant attacked, &c, &c. But, for the 

 sake of example, we will suppose a case in which three or four tea 

 bushes are found to be infested by some scale-insect that is considered 

 to be a dangerous pest. First dig a fair-sized hole in the midst of the 

 affected clump, and place in it some dry grass and sticks as foundations 

 for a fire. Fill two or three buckets with one of the insecticide washes 

 described below. Prune back the branches one by one; immerse each 

 branch completely in the insecticide and throw it into the hole, until 

 nothing but the bare framework of the tree is left. Sweep all fallen 

 leaves and rubbish from beneath the trees into the hole. Next, paint 

 over the bare stems with the same insecticide, using a large paint brush 

 and taking great care to saturate the entire surface down to the ground. 

 Then set fire to the heap of prunings, and cover up the remains with 

 earth. To kill off possible strugglers, the unpruned trees immediately 

 surrounding the affected patch should be thoroughly sprayed with the 

 mixture. If carried out in time, these measures will probably stamp 

 out the pest; but a careful watch should be kept for any fresh outbreak. 



