METHODS OF REPRESSION. 93 
rapidly, as did the Lecaniums, which were constantly attended by 
the ants. The owner sprayed industriously with whale-oil soap, but 
without apparent effect. During 1911 many of the trees died, and 
at the present time (March, 1912) the orchard is practically ruined 
and the owner has abandoned hope of saving enough trees to make the 
orchard profitable. The condition of dying trees is well illustrated 
by Plate VI, which shows a Louisiana Sweet orange tree that has been 
xposed to ant infestation for three seasons. This tree stood near the 
Tvee, outside the barrier ditches described below, and was exposed to 
the work of the ants. 
Another orange orchard which we have had under close observation 
has been infested for 7 years, and during this time no measures have 
been taken to control the ants. In this orchard fully 60 per cent of 
the trees are dead and the remaining trees are heavily incrusted with 
both the chaff scale and the purple scale (LepidosapJies beckii Newm.). 
So abundant are the ants here that a bit of earth disturbed by one's 
foot at any point in the orchard will reveal a seething mass of ants. 
A recent crop from this orchard consisted of but 250 boxes of inferior 
quality. Other orchards, of approximately the same size but not yet 
infested by the ant, produced in the neighborhood of 3,000 boxes. 
At Soccola Canal there is a small tract of land on which four orange 
orchards have been planted in succession, all of which have died before 
reaching bearing age. The entire neighborhood is heavily infested, 
and Mr. S. M. O'Brien, of Nairn, La., states that to his knowledge the 
ants have been abundant at Soccola for at least 17 years. The plat 
has now been entirely abandoned as an orange grove, the last of the 
dead orchards having been removed during 1911 and the land devoted 
to the growing of truck crops. 
METHOD OF DISSEMINATION IN THE ORANGE SECTION. 
As already indicated, the most probable sources of original infesta- 
tions in the orange section were drifting logs in the river, these logs 
carrying living colonies of the Argentine ant. In times of flood these 
logs are thrown up on the batture (the space between the river bank 
and the levee) and remain there in large numbers. It is the history 
of practically all infestations in this section that the ants first appeared 
on the batture, then along the levee, and from the latter worked their 
way back from the river. At all the infested points the levee is found 
to be teeming with the ants and the batture itself is a constant breed- 
ing place. A portion of the infested batture, covered with a thick 
growth of willows, is shown in Plate IX. Here the ant colonies are 
found under every particle of driftwood and trash, and during almost 
the entire year they are in attendance upon CoccidaB and Aphididae 
on the willows. For a number of weeks each year this batture is 
covered with several feet of water from the river, but the infestation 
