The Palatka news. [volume] (Palatka, Fla.) 1905-1908, 1907-01-18
Suggestions About White Fly.

The Florida Agricultural Expert
inent Station has issued the follow
ing bulletin, written by DIR. E. w.
Berger of the Department of Ento-
mology:
The exceptionally low temperature
at Christmas time of 1905 has result
ed in partial or complete defolia-
tion of citrus trees in some northern
sections of Florida, and this fact
again brings up questions of whitefiy
control under such circumstances.
In trees and groves where the
friendly Fungi (the Red, Yellow and
Brown parasitic upon the whitefiy
are found in abundance, it is advised
to collect large quantities of the
dead leaves still clinging to the
trees, or fallen leaves, with plenty of
fungus upon them. These should be
dried and stored, since the fungus
may be useful for again starting it in
the trees and groves next spring.
Methods for introducing the fungi
by spraying the spores suspended in
water on the leaves of trees infested
with whitefiy. or by pinning on
leaves, have been developed (see
Bulletin S8, now in press. The fun
81 when dried have been found to re
tain their vitality for two months
and further observations may extend
this time. Should the leaves with
fungus collected prove useless by the
time that they are required, little
labor will have been lost. Speci-
mems sent to the station ut the
proper time will be gladly tested for
their vitality.
During December, January and
February there are probably but few
ii any unmatched eggs or adults of
the whitefiy; all are in the young
scale-like stages and live attached
to the under surface of the leaves.
They are easily killed by spraying
while in these stages, provided, OF
course, that the spray comes in con-
tact with them. Drying the leaves
will kill them, hence all the
young insects upon leaves dropped
by freezing will die, with the posi-
BILE exception of those nearly ma
tured. For the latter reason all
dead and droped leaves should be de-
stroyed, plowed under or burned, ex-
cepting those wanted for the fungi
on them.
Now, in view of the fact that
itcSHiHH Hao DeSul Gll6 WOIh Vi uC-
foliating, 1T appears desirable to
complete it, or to take advantage of
the reduced number of leaves and
spray with the determination to kill
every remaining whitefiy larva upon
the tree; even going to the extent of
using spray sufficiently strong to
complete the defoliation. One dras
tically thorough spraying at any
time is better than several less
thorough ones. Spraying, further
more, cannot be made effective un-
less all cooperate. If but few green
leaves remain upon tree it is ad-
vised to complete defoliation by
trimming. If, to complete defolia-
ton, spraying is adopted, this should
be done at once before the new buds
start.
While in the above the writer has
emphasized spraying, yet he does
not for moment desire to leave the
impression that he is an unqualified
supporter of spraying for the white
fly. On the contrary, he considers
spraying only in the light of an ex-
pedient, a makeshift, and firmly be-
lieves that the solution of the white
fly problem is closely bound up with
whatever success we can achieve in
devising sure and ready methods for
introducing the fungi and other
parasites. In other words, the solu-
ton of the fungus problem will be
the solution of the whitefiy problem,
and it is believed that the solution
of each is at hand. The reader is
again referred to Bulletin 88, which
will be ready for distribution in a
few days.
For more complete spraying direc-
tions see Bulletin 76 of this Station.
1t is also pertinent to the subject
in hand to emphasize the necessity
for destroying all unnecessary breed
ing places of the whitefly. Under
this head belong the following trees:
Cape jessamine, privet hedges, all
useless and abandoned citrus, china
berry and umbrella trees, viburnum
nudum, and the mock orange CHERRY
laurel) when infested. OF these the
cape jessamine may be defoliated,
but tile work must be complete. All
the others should be cut down and
burned. During summer these trees
are such prolific breeding places for
the whitefiy that the latter becomes
scattered far and wide.