CITRUS EXPERIMENT STATION
LAKE ALFRED, FLORIDA


CES Mimeo Series 68-5


CITRUS INSECT AND DISEASE SUMMARY
END OF JULY 1967


Statewide Index of Abundance


Mi d
July


End Trend
July ,>

-
Frt. V' vs.,m
/ mit
/ Rust mite
f J


-1.5


\ High for


Texas C. mite-
-1.0 O -
0-0-- -w

C. red mite

-0.5


mites

High for
scales;
mealybug


Mid
Ju


JE-d
uly


Black scale"



Glover scal




O--- ------ -0

Yellow scale y
Mealybug


NOTE: Only pests or conditions of general or current interest are reported.
Forecasts are for 1 month in advance unless otherwise indicated.

Rust Mite: 81% of groves infested (Norm 56%); 57% economic (Norm 38%).
Population is above normal and in the high range. Further increase is expected until
the summer peak is reached about mid-August. Gradual decrease will begin in late August
but heavy infestations will be common through September. Highest districts are South (2.27)
Central (1.78) North (1.76) and West (1.73). Mites are more numerous on fruit than on leaves.


Texas Citrus Mite:
Rapid decrease
Further decrease is
districts. Highest


71% of groves infested (Norm 68%); 37% economic (Norm 44%).
has dropped population to the moderate level normal for this period.
expected through August. A few scattered infestations will occur in all
districts are Central (1.70) and South (1.41).


Citrus Red Mite: 46% of groves infested (Norm 69%); 26% economic (Norm 40%).
Population will continue to be below.normal and in the moderate range. Further decrease
to low level is expected through August. Highest districts are West (1.33) and North (.95).
Glover Scale: 84% of groves infested; 28% economic. Population is near normal and in the
high range. Little change is expected. Highest districts are South (1.65) Central (1.30)
and East (1.20).
Purple Scale: 72% of groves infested; 1% economic. Population is below normal and in the
low range with further decrease expected. Highest district is West (.83).
Black Scale: 88% of groves infested; 73% economic. Population reached the summer peak in
late July above normal level. It will decrease in August but is not expected to drop from
the high range until September. All districts are high: East (2.47) South (2.41) West
(2.00) Central (1.85) and North (1.64).
Chaff Scale: 74% of groves infested; 1% economic. Population is near average and in the
moderate range with little change expected. Highest district is Central (1.00).
Yellow Scale: 79% of groves infested; 7% economic. Population is above normal and in the
moderate range. Little change is expected. Highest district is Central (1.15).
Snow scale and lesser snow scale populations are above average.
Whitefly: 59% of groves infested; 19% economic. Population is near the moderate normal
level. Decrease is expected. Highest district is East (1.52).
yMealybug has decreased .into the moderate range and will drop lower.

Spray Notes: Supplemental rust mite control will be necessary in many groves in August.
Recommended materials are sulfur spray or dust or chlorobenzilate or Nabac. Sulfur should
not be applied within 3 weeks of an oil spray. Sulfur spray is less likely to be washed
off by rain than sulfur dust.


675 August 1, 1967 WAS


-2.0


W. A. Simanton