FLORIDA STATE HORTICULTURAL SOCIETY. 
37 
Mr. Waite.—It feeds upon the orange, 
lemon, grapefruit and lime, I have also 
seen it in all stages from the egg to the 
adult fly, on the chinaberry, persimmon, 
cape jasmine and prickly ash. While I 
have never found the larva or pupa on the 
palmetto and gall berry, I have seen the 
adult flies quite abundant. The sooty 
mold attacks the honey dew, following 
the attacks of many kind of wax scale 
and mealy bug. Many have sent me speci¬ 
mens of plants or shrubbery covered with 
this deposit of sooty mold, and asked if 
it was not white fly. On examination I 
found only the wax scale, or mealy bug. 
Mr. Taber.—I would like to hear from 
Prof. Rolfs on fhis question. 
Prof Rolfs.—I was getting more infor¬ 
mation out of this than I could possibly 
give, but some people are never satisfied 
until they get things stirred up. 
The damage done by the white fly, and 
the smut which follows it, does consider¬ 
able damage to the grove that is ordi¬ 
narily not taken into consideration. The 
honey dew, which is excreted by the white 
fly, falls upon the fruit and the upper side 
of the leaves, this makes a medium in 
which the smut or sooty mold grows 
luxuriantly. By its extensive growth it 
forms a velvety covering over the leaves 
and fruit and on account of its black 
color it keeps the sun from penetrating to 
the leaves and fruit or in a large measure 
obstructs it. Sunlight as we all know is 
absolutely necessary for the welfare of 
our orchard trees, and is also absolutely 
necessary for the maturing of the fruit, 
consequently, when the sunlight is cut off 
almost completely, as is often the case 
with this sooty mold covering, the fruits 
cannot mature properly. This is brought 
out very strikingly when the fruit is 
run through a washer. The fruit as it 
hangs on the tree appears to be perfectly 
ripe but when it comes out of the washer 
it is half green, the green area extending 
as far as the fruit is covered with the 
sooty mold. 
The Manatee snail does not destroy the ‘ 
white fly as a number of people have as¬ 
serted. No one who has studied the 
work of this snail with a hand lens, which 
is the proper way to study it, will contend 
for a moment that the snail does any 
harm to the white fly. It merely feeds on 
the sooty mold cleaning it off completely 
from the leaves and. from the fruit, doing 
the work much more perfectly than any 
washer yet invented. 
The good work of the Manatee snail 
in clearing off the sooty mold was strik¬ 
ingly apparent in a number of cases. The 
trees that had been cleared of the sooty 
mold a year before produced an abun¬ 
dant bloom and set a heavy crop of fruit, 
while the adjoining trees bloomed rather 
sparsely and set, probably, a half crop of 
fruit. So far as the natural conditions sur¬ 
rounding these trees was concerned they 
seemed to be alike, there was every rea¬ 
son for believing that the beneficial effect 
was attributable to the work of the snail. 
Maj. Fairbanks.—I would like to 
know about the white fly on younger 
growth, as it did not seem to be on the 
older growth. 
Professor Rolfs.—The females deposit 
their eggs on the younger foliage, as 
young trees are usually making a vigor¬ 
ous growth, these are apt to have more 
eggs deposited upon them proportionally 
than the large trees. It sometimes hap¬ 
pens that a tree will send up a water 
sprout while the rest of it is practically 
dormant, if this occurs during the flight 
of the white fly, the water sprout will be 
