Insects 
J. R. Watson, Gainesville 
Mr. President, Ladies and Gentlemen : 
It is my purpose this morning- to briefly 
present to you the present status of three 
recently introduced and rapidly spreading 
pests of citrus trees. The first is 
THE WOOLLY WHITE FLY. 
This was introduced into Florida, pre¬ 
sumably from Cuba, about 1908 or 1909. 
At least it was first discovered in Tampa 
(by Dr. Back) in November, 1909. 
It has spread with phenomenal rapidity 
and is now found pretty generally distrib¬ 
uted over the area inclosed in the black 
line. Map. 
Because of the evil record of its rela¬ 
tive, the common citrus whitefly, we have 
been watching this species rather closely 
for the past two years. 
APPEARANCE 
I need not describe its appearance as 
the specimens I have will do that better 
than I can. No other species in Florida 
has this woolly coat. Its development in 
colonies or groups is characteristic. 
The third insect is the 
MANGO SCALE. 
The mango scale was introduced a few 
years ago into the Miami region. It is 
now found also about Fort Myers, and 
has recently appeared about Winter Ha¬ 
ven. It is said to be the worst pest they 
have on citrus in southeast Asia. As to 
what it is destined to do in Florida we 
can only guess at present. I mention it 
this morning chiefly to call your attention 
to the specimens I have that you may be¬ 
come familiar with it. 
It is important to be able to distinguish 
between it and the pyriform scale so com¬ 
mon on avocados, ficus and other plants. 
It can, however, be told by the shape, 
which is that of a shield, instead of pear- 
shaped, and by the bright green larvae. 
The mango scale, as its name indicates, 
attacks, beside citrus, mangoes, guavas, 
figs, loquats, roseapple, and a number of 
ornamental plants. It is especially bad on 
mangoes. 
When first discovered in Miami there 
was very little of this scale. If we had 
had at that time a crop pest law, and even 
a little money with which to enforce it, 
this pest could probably have been 
stamped out. 
In addition I have here some specimens 
of the fruit fly, the new and apparently 
very efficient parasite of the Florida red 
scale. Also some Mediterranean Fruit 
Fly. 
Damage.. The amount of harm that 
this insect has done to the groves it has 
infested has been very variable. In the 
vast majority of cases the owner has 
scarcely been aware of its presence. A 
dozen or so leaves per tree showed col- 
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