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that as far as the plant requirements are concerned, only the sur- 

 face of the soil need be kept in a friable condition, but I think it 

 well to frequently stir the soil about fruit trees to a considerable 

 depth to break up and disturb the queen and larval chambers of 

 the ant nests about the roots since these insects are very active 

 in the distribution of the scale insects. For the same reason it 

 would be well to occasionally flood the area about the trees for a 

 period of several hours. In pruning, furthermore, the purpose 

 of the trees may not require leaving the center open so that a free 

 access of light and air is possible, but just this condition is un- 

 favorable to the development of scales and mealy-bugs, and should 

 be practiced. Also such a method of pruning makes thorough 

 spraying possible. Enough has been said to show that cultural 

 methods can be made an important factor in orchard insect con- 

 trol. 



ORCHARD SANITATION. 



I have seen owners spraying for the Avocado Mealy-bug and 

 allowing wild guava to grow about the place simply covered with 

 the same insect. Obviously the guava should have been eradi- 

 cated. If Hawaii is to become a fruit producing country, it must 

 of necessity learn the lesson of putting on the market not alone 

 fruit, but clean fruit. All manner of places that will harbor in- 

 sect pests must be done away with. Many plants of no economic 

 importance are included in the list of food plants of many of the 

 insect pests. What good to fight the pests on the fruit trees and 

 leave these plants to breed new generations ? Rubbish piles must 

 be burned, and the fallen fruit and culls destroyed. After harvest- 

 ing a crop, the orchard should be as clean as it is possible to 

 make it. This preventive work pays. 



NATURAL ENEMIES AND QUARANTINE. 



The first three methods of insect control, namely, direct meas- 

 ures, cultural methods and sanitation are of the most importance 

 to the fruit-grower himself, since they are metnods actually within 

 his power to use at a time when his trees are menaced by 

 injurious insects. However, there yet remains to be men- 

 tioned two more methods, that is, natural enemies and quarantine. 

 It may be that the time will come when orchard sanitation, na- 

 tural enemies and quarantine will obviate the necessity of direct 



