The champion. (Arcadia, Fla.) 1895-1911, 1908-11-26

writer has made the following statement
concerning isolation Of grove as re-
quifement for successful results in fumi-
eating for the white fly:
"a distance OF one half mile between
a given grove and the nearest infected
grove is sufficient to insure against APP
preciable interference with the results Of
the treatment through the migration of
adults between the groves"
The bulletion referred to was written
in the fall Of 1907 and owing TO the de-
lay in publication an opportunity was
afforded to revise and amend the text in
minor particulars to conform fully with
the retults Of the extensive fumigating
experiments conducted In the winter OF
1908 as far as worked out up to June
1908. The final results OF these expert,
ments could not be obtained until late in
the season.
Among the additional information OF
value in connection with fumigation con-
siderable data has been obtained show
ing the rapidity with which fumigated
groves, or sections of groves, become re-
infested from neighboring or adjoining
groves. From the experiments conduc-
ted during the winter OF 1907 meager
data was obtained on this point and the
writer was justified in drawing only the
conclusion part OF which Is quoted above
from bulletin 76. The more extensive
data now at hand obtained by the writer
and one Of his associates, Mr.. w w.
yothers, shows the wider applicability
Of fumigation for the white fly than at
first supposed It is believed that brief
summary Of this data at this time will be
Of value to those who contemplate adopt
ing thit practice.
At the end Of the season of multiplica-
tion OF the fly the results of fumigation
last winter are found to be still strikingly
evident even when the fumigated trees
are located in the midst OF untreated
trees. Observations under these condi-
ions we're made in four different groves.
The difference In the white fly infesta-
alton in these four instances at the end
# the breeding season amounted to Is,
70, 80 and &c per cent. respectively in
avor OF the fumigated trees, the average
,eing SO per cent. With such differences
IS these when the treated trees are sur
'ounded by untreated trees it is obvious
hat an isolation OF two or three hundred
|eet would ordinarily insure immunity |
rom the occurrence OF the hy In injuri- |
gus abundance for at least one season.
such proves to be the case at grove Of
Mr. John r. Fuller located 10 the west
an part Of Orange county. In this
rove the white fly averaged more than
me hundred pupae per leaf In the sec
ion funigated in February, 1905 At
present with the foliage and fruit entire
y>free from the sooty monld the average
i've pupae (no larvae or adults presently
YER leaf is FL, although the fumigated
rees are not more than 200 feet from
eavily infected grove where the average
lumber of pupae per leaf is at present
rs as shown by extensive examinations.
is doubtful II the flies in the fumi-
ated section would multiply to the ex-
mt OF blackening the foliage II not fur
ier checked until the winter OF l909-10.
ut in order to delay the spread Of the
est to other sections of his extensive /
rove, which is one of the most valuable
the State, Mr. Fuller will probably
inigate these same trees again during /
lie coming winter.
Further evidence along this line might
. mentioned but the foregoing records
III be sufficient to show that isolation Il
Ia grove, while important, Is not essen n
al to surcess in controlling the fly by
There are, uuquestionably, Ii |,
which would render fumi- b
ltion improbable. For example, it a
ould not be profitable ordinarily to flu y
ieate small grove Of from FIVE to ten
fess immediately adjoining q heavily :.
tested grove Of 20 or 80 acres. But on v
( other hand the owner of grove Of II
b acres or more need not be deferred j.
m, n, ~, occotsuf If M i,1fpe- VI