CITRUS EXPERIMENT STATION
LAKE ALFRED, FLORIDA

CITRUS INSECT AND DISEASE SUMMARY
END DECEMBER 1966


CES Mimeo Series 67-19
CES Mimeo Series 67-19


Statewide Index of Abundance
1 9 1 1


End
Nov.
V1


Mid
Dec.


End
Dec.


Trend


-l.5
a..-


_____-


------ ---
Rust mite -
-1.0
C. red mite
O--- ---------
-0. --0-- __->
-0.5

x T7exas C. mite


High for


rust mite

High for


scales;
winter high
for
CRM & TCM


End
Nov.


Mid
Dec.


End
Dec.


Trend


Scales
S-->Glov

S..- - --Prp -> haf

____ -- .-- ----->Chaf


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

Rust Mite: 60% of groves infested (Norm 57%); 41% economic (Norm 38%).
Population has recently dropped from the high range and is slightly above the
normal levels of abundance for year end on both leaves and fruit. Little change is ex-
pected. Important infestations will occur in all districts. Highest districts are
West (2.00) South (1.48) and North (1.41).

Citrus Red Mite: 45% of groves infested (Norm 37%); 19% economic (Norm 10%).
Population increased in late November and by mid-December was at the highest
December level since 1958. Slight increase is expected from current moderate level.
All districts will have a few important infestations. Highest districts are West (1.29)
and North (.77).

Texas Citrus Mite: 34% of groves infested (Norm 39%); 10% economic (Norm 16%).
Population increased but is still below normal December level. Slight increase is
expected in January but only scattered infestations will be important. Highest districts
are West (1.21) and North (.64).

Glover Scale: 76% of groves infested; 11% economic. Population is above average and in
the moderate range. Slight increase is expected. Highest districts are Central (1.00)
and East (.96).
Purple Scale: 75% of groves infested; 8% economic. Population is normal and in the
moderate range. Little change is expected. Highest district is East (.91).
Chaff Scale: 48% of groves infested; 4% economic. Population is below normal and in
the low to moderate range. Little change is expected. Highest district is East (.70).
Yellow Scale: 66% of groves infested; 12% economic. Population is above average and
in the moderate range. Little change is expected. Highest districts are East (1.04)
and Central (.94).
Black Scale: 35% of groves infested; 13% economic. Population has increased to normal
level for December. Further increase will occur unless subfreezing weather slows de-
velopment, but infestations are not expected to be important in winter.
Snow Scale: 8% of groves infested; 3% economic. This scale is present in more survey
groves and infestations are heavier than in any prior month in 16 years of record.

Whitefly larvae will be moderately abundant on leaves but adults and eggs will be scarce
until March.


Spray Notes:
winter before
a combination


Rust mite, citrus red mite, and Texas citrus mite should be controlled in
more than 15% of leaves become infested with any one of these species or
of them. See December 7 Spray Notes.


650-January 4, 1967 WAS


W. A. Simanton