THE ARGENTINE ANT IN RELATION TO CITRUS GROVES. 6 
pests, as indicated by the number of titles on this subject appearing 
in entomological literature, has increased greatly throughout the 
world in the past 10 years. 
The principal convictions which had arisen, on the influence of 
the Argentine ant on citrus fruit trees in Louisiana, are expressed 
in the writings of Dr. Titus 1 and Messrs. Newell and Barber. 2 
Titus states, substantially, that the ants aid in the distribution of 
aphids and scale insects on citrus and other trees, remove young 
scales to new territory, establish colonies of certain species, and 
appear to have become caretakers for all kinds of scales and plant- 
lice. 
Newell and Barber, in addition to expressing the belief that the 
ants shelter and protect scale insects, aphids, and white flies, and 
establish them upon other plants, are of the opinion that it is in the 
orange groves that this ant has inflicted probably the most serious 
injury. They note that ant invasion is followed by so rapid an in- 
crease of scale insects that, unless prompt measures are taken against 
the ants, the second year of infestation shows a severe reduction in 
the crop, the third year almost complete loss, and the fourth or fifth 
year witnesses the death of many of the trees. These authors state 
further that the ants are particularly severe in their attacks upon 
the blossoms of the orange. 
The opinion of the Louisiana orange growers themselves on this 
subject may be summarized from the answers received to inquiries 
made and submitted in 1914 as to whether the ant injures the trees 
and in what ways. Of those growers replying to the question, about 
61 per cent believed it to be injurious, 33 per cent stated that they 
did not know, and about 6 per cent believed that it was not injurious. 
The prevailing beliefs as to the nature of the injury were, (1) that 
it prevents bearing, (2) destroys blossoms and roots, (3) eats feeder 
roots, (4) destroys the fruit, (5) takes the sap out of the new growth, 
(6) causes the death of limbs by traveling continuously over the 
same spot, and (7) injures the bloom, causing the oranges to drop. 
It was believed also that the ants increase, disseminate, and protect 
scale insects and drive out lady-beetles. One answer, however, was 
to the effect that the ants are beneficial because they destroy other 
msects. It was generally agreed that the ant causes most severe 
injury to the orange trees, resulting in a complete loss of crop and 
culminating in the death of the trees. 
A preliminary survey of the orange orchards of Louisiana made 
it plain that many of them were suffering from some undetermined 
noxious influences. The trees were, as a rule, undersized, poorly 
shaped, lacking in the abundance of clear, dark green foliage which 
iOp. cit., p. 79-84. i Op. cit. 
