4 BULLETIN" 965, U. S. DEPARTMENT OF AGEICULTURE. 



eradication of the ant in every instance resulted in a reduction of 

 the mealybug infestation to commercial control within a period of 

 from 1 to 3 months. This has been largely due to the increased and 

 unrestricted activity of predatory insects already established. 



The citrophilus mealybug, Pseudococcus gahani (Green) ^ was first 

 recorded as an orchard pest in 1914 and has never been observed as a 

 severe pest in citrus orchards except in localities infested with the 

 Argentine ant. 



The influence of the ant on increased severity of scale pestS; while 

 less important than on mealybugs, must be considered. The black 

 scale, Saissetia oleae (Bern.), and soft brown scale. Coccus hesperi- 

 dum L., have been observed to become decidedly more numerous on 

 trees attended by large numbers of ants than in other parts of the 

 same orchard entirely free of the ants. Trees severely infested with 

 the soft brown scale have been rapidly freed by the action of pari- 

 sitic insects following the control of this ant. 



It is entirely possible that the Argentine ant distributes fungous 

 and bacterial diseases, although no specific evidence has been noted. 

 Attracted as they are" by the honey dew of insects, their habit of 

 carrying this and various other substances, both animal and vegetable, 

 their colonization and movement over the ground, and their constant 

 attendance to all parts of the trees offer ready means of distributing 

 brown rot, gum disease, and other maladies of citrus. In this con- 

 nection ants would appear to be especially deserving of attention in 

 pear orchards through their possible relation to blight. 



OTHER RELATIONS. 



Beekeeping in sections heavily infested with the Argentine ant is 

 most difficult and proves successful only after a strenuous campaign 

 is instituted to control or exterminate the pest. The ant is exceedr 

 ingly fond of honey and, furthermore, attacks the bee larvee. The 

 ant's small size, great numbers, and persistent effort to reach desired 

 food make it an enemy with which the bees are unable to cope long. 



As a household pest the Argentine ant has proved particularly 

 annoying. It invades all parts of the house in search of food, and 

 the intolerable conditions brought about in heavily infested districts 

 render the houses less desirable for places of residence.^ 



DISTRIBUTION. 



The Argentine ant appears to have been first noted in California 

 in 1905 by Dr. E. S. G. Titus, at Ontario, although it did not come 

 into prominence until 1908, when a general survey of its dis- 



3 The role of this msect as a household pest has been fully described by Mr. E. R. Barber of this 

 department in Farmers' Bulletin 1101, United States Department of Agriculture. 



