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 Copyright
 Title Page
 Table of Contents
 Introduction
 Fruit damage survey December...
 February and March valencia orange...
 Components of the fruit loss following...
 Tree losses from Decemeber...
 September 1963 condition of sample...
 Summary






Group Title: Mimeo Report - Department of Agricultural Economics, University of Florida - EC 64-7
Title: Florida citrus fruit and tree losses from the December, 1962 Freeze
CITATION PAGE IMAGE ZOOMABLE PAGE TEXT
Full Citation
STANDARD VIEW MARC VIEW
Permanent Link: http://ufdc.ufl.edu/UF00071991/00001
 Material Information
Title: Florida citrus fruit and tree losses from the December, 1962 Freeze
Series Title: Agricultural Economics mimeo Report
Physical Description: 34 p., : illus., ; 28 cm.
Language: English
Creator: Stout, Roy G
Publisher: University of Florida, Dept. of Agricultural Economics
Place of Publication: Gainesville Fla
Publication Date: 1964
 Subjects
Genre: non-fiction   ( marcgt )
 Notes
Statement of Responsibility: Roy G. Stout.
General Note: Jan. 1964.
Funding: Florida Historical Agriculture and Rural Life
 Record Information
Bibliographic ID: UF00071991
Volume ID: VID00001
Source Institution: Marston Science Library, George A. Smathers Libraries, University of Florida
Holding Location: Florida Agricultural Experiment Station, Florida Cooperative Extension Service, Florida Department of Agriculture and Consumer Services, and the Engineering and Industrial Experiment Station; Institute for Food and Agricultural Services (IFAS), University of Florida
Rights Management: All rights reserved by the source institution and holding location.
Resource Identifier: oclc - 29122770

Table of Contents
    Copyright
        Copyright
    Title Page
        Title Page
    Table of Contents
        Table of Contents
    Introduction
        Page 1
    Fruit damage survey December 26-30
        Page 1
        Page 2
        Page 3
    February and March valencia orange maturity test and yield averages
        Page 4
        Survey results
            Page 4
            Page 5
            Page 6
            Page 7
        Estimating juice yield of valencias following a freeze
            Page 8
    Components of the fruit loss following the Decemeber 1962 freeze
        Page 9
        Growth pattern following the freeze
            Page 10
            Page 11
            Page 12
            Page 13
            Page 14
        Droppage pattern following the freeze
            Page 15
            Page 16
            Page 17
            Page 18
            Page 19
        Other factors influencing freeze losses
            Page 20
            Page 21
            Page 22
        Estimated components of fruit losses
            Page 23
            Page 24
            Page 25
            Page 26
    Tree losses from Decemeber freeze
        Page 27
        Page 28
    September 1963 condition of sample groves used in fruit count surveys
        Page 29
        Page 30
        Page 31
    Summary
        Page 32
        Page 33
        Page 34
Full Text





HISTORIC NOTE


The publications in this collection do
not reflect current scientific knowledge
or recommendations. These texts
represent the historic publishing
record of the Institute for Food and
Agricultural Sciences and should be
used only to trace the historic work of
the Institute and its staff. Current IFAS
research may be found on the
Electronic Data Information Source
(EDIS)

site maintained by the Florida
Cooperative Extension Service.






Copyright 2005, Board of Trustees, University
of Florida




JANUARY 1964
^ -> ,,


AGRICULTURAL ECONOMICS MIMEO REPORT EC 64-7


C (EIitURIN TO ASSISiT ViT: ':ECTO


FLORIDA CITRUS FRUIT AND TREE

LOSSES FROM THE DECEMBER,

1962 FREEZE
ROY G. STOUT




175

150 152.4 iii52.

125 1961-62
|V HARVEST
0 100 106.5
Z 93.2
O
0 75 1962-63
=! HARVEST December 1
1963-64
50 ESTIMATE

25

0











THE DEPARTMENT OF AGRICULTURAL ECONOMICS, UNIVERSITY OF FLORIDA, GAINESVILLE
in cooperation with
THE FLORIDA CROP AND LIVESTOCK REPORTING SERVICE, ORLANDO, FLORIDA












CONTENTS


INTRODUCTION. . . . . . .




FRUIT DAMAGE SURVEY DECEMBER 26-30. . . .




FEBRUARY AND MARCH VALENCIA ORANGE
MATURITY TEST AND YIELD AVERAGES. . . . .

Survey Results . .. . . .

Estimating Juice Yield of Valencias
Following A Freeze .. . . .


COMPONENTS OF THE FRUIT LOSS FOLLOWING
THE DECEMBER 1962 FREEZE. . . .

Growth Pattern Following the Freeze. .

Droppage Pattern Following the .Freeze..

Other Factors Influencing Freeze Losses.

Estimated Components of Fruit Losses .


. 9 9 .

9 9 9 9

9 9 9 9

* 9 9 9

9 9 9 9


TREE LOSSES FROM DECEMBER FREEZE. . . . .


SEPTEMBER 1963 CONDITION OF SAMPLE GROVES
USED IN FRUIT COUNT SURVEYS . ... 29


SUMMARY . . .. .. . . 32


Page

1




1





4

4


8












FLORIDA CITRUS FRUIT AND.TREE LOSSES
FROM THE DECEMBER, 1962 FREEZE


Roy G. Stout



INTRODUCTION


The official forecast of the Florida citrus crop on December 10,

1962, totaled 120.5 million boxes of oranges, 38 million boxes of grape-

fruit, 4.3 million boxes of tangerines and 800,000 boxes of tangelos.

Due largely to the severe freezes on the nights of December 12 and 13,

the final production was reduced by 38.3 percent for oranges, 21.1 per-

cent for grapefruit, 53.5 percent for tangerines and 6.3 percent for

tangelos. Considerable information was collected by the Florida Crop

and Livestock Reporting Service for making revisions of later forecasts

of the size of the crop. Some of this information was from the regular

re-occurring surveys and other information was collected.from special

surveys. Some of the,more important aspects of the accumulated data

are summarized in this report.


FRUIT DAMAGE SURVEY DECEMBER 26-30


A special fruit damage survey was conducted during the week of

December 26 to 30, 1962; two weeks following the freeze. Fruit was cut

and scored according to the Florida Department of Agriculture Inspection

Service standards for Damage. Cuts of individual fruit were made at












FLORIDA CITRUS FRUIT AND.TREE LOSSES
FROM THE DECEMBER, 1962 FREEZE


Roy G. Stout



INTRODUCTION


The official forecast of the Florida citrus crop on December 10,

1962, totaled 120.5 million boxes of oranges, 38 million boxes of grape-

fruit, 4.3 million boxes of tangerines and 800,000 boxes of tangelos.

Due largely to the severe freezes on the nights of December 12 and 13,

the final production was reduced by 38.3 percent for oranges, 21.1 per-

cent for grapefruit, 53.5 percent for tangerines and 6.3 percent for

tangelos. Considerable information was collected by the Florida Crop

and Livestock Reporting Service for making revisions of later forecasts

of the size of the crop. Some of this information was from the regular

re-occurring surveys and other information was collected.from special

surveys. Some of the,more important aspects of the accumulated data

are summarized in this report.


FRUIT DAMAGE SURVEY DECEMBER 26-30


A special fruit damage survey was conducted during the week of

December 26 to 30, 1962; two weeks following the freeze. Fruit was cut

and scored according to the Florida Department of Agriculture Inspection

Service standards for Damage. Cuts of individual fruit were made at










depths of 1/4 inch, 1/2 inch and at the center (1/8 inch, 1/4 inch and

center cut for tangerines). Center damage was scored as minor or major

according to the extent of injury. Each fruit was classified based on

the deepest cut at which damage was observed; the fruit was not cut where

rind breakdown was observed. Sixteen oranges and tangerines and 5 grape-

fruit from 4 trees were scored in groves previously selected for objective

fruit counts in preparing the crop estimate,. Slightly over 1,100 groves

were included in the survey0 A summary of the fruit damage condition of

this survey is shown in Table 1.


Table lo--Condition of Fruit.on Trees Observed in Selected Groves
December 26-30, 1962
No Damage Damage Damage to Center Cut Rind
Fruit Type Damage at at Minor Major Break-
Apparent 1/4" Cut 1/2" Cut down
Percent Percent Percent Percent Percent Percent
ORANGES:
Early and
Midseason 700 8,0 13o2 24,0 46.8 1.0
Temples 8o4 2,5 2o4 5.3 77.0 4.4
Valencias 32o0 15o8 16,3 19.2 16.5 0.2

GRAPEFRUIT:
White Seedless 50,5 8,9 7,2 10.1 21,3 2,0
Pink Seedless 40,6 6,1 4,3 11.8 35,1 2.1
Seedy 44,6 12,5 13,0 12,1 17.6 0.2

TANGERINES 3,8 1o7L l.2/ 14,7 75.5 2.7

1/ 1/8 inch cut.
1/ 1/4 inch cut.
Source: Florida Crop and Livestock Reporting Service, Florida Citrus
Freeze Damage Report, January 2, 1963,


Fruit was more seriously damaged in the 1962 freeze than in the

1957 freeze. In a similar survey in 1957 the following percentages of

damage at the center cut were recorded: Early and Midseason oranges,










47 percent; Valencias, 28 percent; White Seedless grapefruit, 9 percent;

Pink Seedless grapefruit, 33 percent; and Tangerines, 57.percent.

In this same survey observations were recorded on the leaf

condition of 4 trees in each of the sample groves. The severity of leaf

damage was classified according to: (1) no damage, (2) minor damage, in

which leaf curl or leaf drop was not extensive, (3) serious damage, where

severe leaf curl or major defoliation was found, and (4) very serious

damage, where substantial numbers of dead leaves were still hanging on

trees. This information is summarized in Table 2.


Table 2,--Leaf Damage Observed in Trees in Selected Groves,
December 26-30, 1962
No Minor Serious Very Serious
Fruit Type
SDamage Damage Damage Damage

Percent Percent Percent Percent
ORANGES:
Early and Midseason 16.9 12o3 43.9 26.9
Temples 27.3 18.8 23.7 30.2
Valencias 2306 15.3 36.9 24.2

GRAPEFRUIT:
White Seedless 50o2 11o3 33.0 5.5
Pink Seedless 48.5 13.6 26.6 11.3
Seedy 13.9 18.3 53.1 14.7

TANGERINES: 21o5 26.7 28.0 23.8

Source: Florida Crop and Livestock Reporting Service, Florida Citrus
Freeze Damage Report, January 2, 1963.


The heaviest damage occurred in the West Coast and.Northern Interior

areas. The Indian.River production area escaped.with minor damage. The

Southern .East.side of the "ridge" in the.Lower Interior suffered less damage

than most other citrus areas .of.the state. These observations following

the December 26-30 survey were .substantiated .in latter reports from size,

droppage, andtree damage surveys.










FEBRUARY AND MARCH VALENCIA ORANGE.MATURITY TEST
AND YIELD AVERAGES


Three special surveys were conducted.in (1) late February,

(2) early March and.(3) late March, 1963,.to determine the state of

maturity.and yield averages.(pounds solids and juice.per 90 pound box)

of Valencia oranges. ,The freeze .created a state .of uncertainty about the

condition.of Valencia.oranges. The sample groves .were the same as those

Valencia groves visited in.the .December 26-30 survey reported above.

Three oranges .were obtained.from.each.of five trees .in each grove for

these tests.

Survey Results


The results of the.first of .these .3 surveys is shown by area,

age group,,and state .in Table .3. The ,lack of damage in.the Indian River

area (East.Coast) is indicated ,by soluble solids .average of 12.48 percent,

pounds .solids.of 6.69, and pounds.of juice .per 90 pound box.of 53.5, as

compared to 10.40, 3.73, and ,35.6.for the heavily.damaged West Coast area,

Tables .4 and 5 .show the ,comparison .of-the .3 bi-weekly tests of

the groves that.were not picked during the.period covered by .the 3 surveys.

These tests included 123 of the original 318 .groves. Groves were.substi-

tuted for picked groves during each .succeeding .survey but .these substitute

groves were.not included in Tables ..or 5 ,in order to make it possible to

show the change in status of the same.groves. This rate of change only

reflects changes in groves unharvested since the more severely' damaged

groves were picked first. Hence these identical groves.were less severely

damaged.than.those previously picked. Very little change .occurred in the

soluble solids, in ,fact.the .last .2 .tests were exactly the.same at 10.90










FEBRUARY AND MARCH VALENCIA ORANGE.MATURITY TEST
AND YIELD AVERAGES


Three special surveys were conducted.in (1) late February,

(2) early March and.(3) late March, 1963,.to determine the state of

maturity.and yield averages.(pounds solids and juice.per 90 pound box)

of Valencia oranges. ,The freeze .created a state .of uncertainty about the

condition.of Valencia.oranges. The sample groves .were the same as those

Valencia groves visited in.the .December 26-30 survey reported above.

Three oranges .were obtained.from.each.of five trees .in each grove for

these tests.

Survey Results


The results of the.first of .these .3 surveys is shown by area,

age group,,and state .in Table .3. The ,lack of damage in.the Indian River

area (East.Coast) is indicated ,by soluble solids .average of 12.48 percent,

pounds .solids.of 6.69, and pounds.of juice .per 90 pound box.of 53.5, as

compared to 10.40, 3.73, and ,35.6.for the heavily.damaged West Coast area,

Tables .4 and 5 .show the ,comparison .of-the .3 bi-weekly tests of

the groves that.were not picked during the.period covered by .the 3 surveys.

These tests included 123 of the original 318 .groves. Groves were.substi-

tuted for picked groves during each .succeeding .survey but .these substitute

groves were.not included in Tables ..or 5 ,in order to make it possible to

show the change in status of the same.groves. This rate of change only

reflects changes in groves unharvested since the more severely' damaged

groves were picked first. Hence these identical groves.were less severely

damaged.than.those previously picked. Very little change .occurred in the

soluble solids, in ,fact.the .last .2 .tests were exactly the.same at 10.90










percent. The percent acid declined.from 1.19 to 1.01 percent. The

over-all loss in juice.yield was 1.5 pounds,.down from 43.3 pounds for

the first test to 41.8 pounds .for the third test. By age group, the 5-9

year old group declined by 2.5 pounds.followed by the over 25 years old

with a decline of 1.9 pounds. The 2 middle .aged groups showed less change.


Table 3.--Maturity Test and Yield Averages.of a Sample of .318 .Valencia


Orange Groves, by Area, Age Group

Age IAcid
Group Groves Test


Number

2
3
10
14
29

35
23
31
35
124

18
7
19
67
111

16
12
10
16
54

71
45
70
132


I I
Percent

1.02
1.24
1.43
1.43
1.38

.93
1.01
1.17
1.20
1.08

.92
1.02
1.13
1.16
1.11

.96
1.21
1.06
1.16
1.09

.94
1.08
1.18
1.20
1.16


East Coast





Upper Interior





Lower Interior





West Coast





State


Total 318


.and,.State Februa
Soluble Acid-


Solids
(Brix)
Percent

11.94
11.77
12.69
12.57
12.48.

9.81
10.26
10.75
10.45
10.31

10.26
10.46
10.74
10.58
10.55

9.98
10.93
10.48
10.37
10.40

10.02
10.57
10.99
10.73
10.71


Solids
Ratio


11.70
9.61
8.98
8.88
9.18

10.73
10.26
9.27
8.97
9.78

11.28
10.29
9.56
9.24
9.69

10.49
9.14
9.96
9.07
9.67

10.84
10.14
9.41
9.11
9.43


ry 19, 1963
Yield
Per 90 lb. Box
Solids I Juice
Pounds Pounds

6.15 51.5
6.14 51.7
6.76 53.1
6.84 54.4
6.69 53.5

3.40 34.1
3.81 36.9
4.22 39.0
4.02 38.4
3.86 37.1

4.23 40.9
4.12 39.3
4.66 43.3
4.47 42.3
4.44 42.1

3.29 32,8
4.09 37.1
3.75 35.6
3.88 37.4
3.73 35.6

3.66 36.0
4.09 38.3
4.64 41.7
4.53 42.0
4,43 41.0


I I


Years

5- 9
10-14
15-24
25+
Total

5- 9
10-14
15-24
25+
Total

5- 9
10-14
15-24
25+
Total

5- 9
10-14
15-24
25+
Total

5- 9
10-14
15-24
25+


Source: Florida Crop and Livestock .Reporting Service, Florida Citrus,
Late Orange.Maturity Test and Yield.Averages, February 27, 1963.

















Table 4.--Comparison of Maturity Tests for an Identical Sample of 123 Valencia Groves in Three
Succeeding Surveys Made February 18-22, March 4-7, and March 18-21, 1963

Age Groves Acid Test Soluble Solids Ratio
Age Groves ...11 .. ... ..... ....... ... ..... ... .....
Group Sampled Feb. Mar. Mar. Feb. Mar. Mar. Feb. Mar. Mar.
18-22 4-7 18-21 18-22 4-7 18-21 18-22 4-7 18-21


Percent Percent Percent Percent Percent Percent


1.11
1.25
1.23

1.19


.94
1.11
1.18
1.15

1.13


.86
1.04
1.05
1.02


10.42
10.77
11.42
10.96


10.26
10.56
11.32
10.96


10.31
10.94
11.29
10.87


1.01 10.97 10.90 10.90


Ratio Ratio Ratio


10.66
9.88
9.62
9.02


9.45


10.98
9.63
9.62
9.64


12.30
10.77
10.85
10.78


9.80 10.98


Years Number


5- 9
10-14
15-24
25+


All Ages 123


Source: Florida Crop and Livestock Reporting.Service; Florida Citrus, Late Orange Maturity Test
and Yield Averages, March 27, 1963.



















Table 5.--Comparison of Yield Averages for an Identical Sample of 123 Valencia Groves in Three
Succeeding Surveys Made February 18-22, March 4-7,.and March 18-21, 1963
Age Groves Solids per 90 lb. Box Juice per 90 lb. Box
Group Sampled Feb. 18-22 Mar. 4-7 Mar. 18-21. Feb. 18-22 Mar. 3-7 Mar. 18-21

Years Number Pounds Pounds Pounds Pounds Pounds Pounds

5- 9 15 4.30 4.15 4.00 40.6 39.7 38.1
10-14 15 3.97 3.95 3.95 36.9 36.6 36.6
15-24 26 5.37 5.27 5.25 46.2 45.6 45.8
25+ 67 4.89 4.77 4.70 44.3 43.0 42.4
-- ------------------------------------------------------------ -
All Ages 123 4.81 4.70 4.64 43.3 42.4 41.8

Source: Florida Crop and.Livestock Reporting Service, Florida Citrus, Late Orange Maturity Test
and Yield Averages, March 27, 1963.










Estimating Juice Yield.of Valencias Following A Freeze


The relationship between the observations of fruit condition

and leaf condition shown in Tables 1 and 2, various weather information,

and the pounds.of juice per 90 pounds of fruit in the February 18-22

survey was analyzed.using multiple .regression analysis. Quantitative

values.were placed on.the fruit and leaf condition of the December 26-30

survey by assigning the .following values to the .different classifications.


Assigned Assigned
Fruit .Condition Value Leaf Condition Value

No Damage 0 No Damage 0
1/4" Cut Damage 1 Minor Damage 1
1/2" Cut Damage 2 Serious Damage 2
Center Cut Damage Minor. 3 Very Serious.Damage 3
Center Cut Damage Major 4
Rind Breakdown 5


A value .was determined.for each grove for the December 26-30

survey basedon.the above scoring.procedures.. In.addition.various weather

data were collected from the U. S. Weather Station closest.to.each sample

grove. These weather variables were:

(1) Minimum Temperature on.December 13
(2) Minimum.Temperature on December 14
(3) Number of Hours Below 28 F .on.December 13
(4) Number of Hours Below 280 F. on December 14
(5) Total.Number.of Hours-Below.280 F. on December .13 & 14.

These.five variables plus.the variables .of fruit condition and leaf con-

dition (All this information was .available on December 30) were.used in

a regression .analysis to.determine the effect on the pounds.of juice per

90 pound box.from the.first.survey on February 18 mentioned .previously.

The 3 significant variables were: (1) Leaf damage score from December










26-30 survey, (2) number of hours below 280 F. on December 13.and 14 and

(3) fruit damage score from the December 26-30 survey.

The February 18-22 survey showed an average pounds.juice.per 90

pound box of 41 pounds. Assuming .an average value of.50 pounds of juice

without.a.freeze, then 9 pounds of juice were lost from -the freeze until

the February 18-22 survey. According to the regression.analysis the

change in values of the 3.variables (1) leaf damage, (2) hours below 280

Fo on December 13 & 14 and (3) fruit condition accounted.for,67 percent

of this loss .in juice weight0

The equation was

Y = 55.80 o045X1 .471X2 o011X3

where
Y = February 18th,.pounds juice
X1 = leaf damage score
X2 = number of hours below 280 F, on December 13 & 14
X3 = fruit damage score
The regression .coefficients .are all significant at
o05 level

This.equation may be useful following a future freeze in predicting juice

loss if.surveys are conducted.2.weeks.after the freeze to determine leaf

and fruit condition values in.a similar manner to the above reported surveys.


COMPONENTS OF THE FRUIT LOSS FOLLOWING THE
DECEMBER, 1962 FREEZE


In revising the citrus .crop forecasts following the freeze it

was necessary to make changes in.the prediction of the average harvest

size that the fruit.would attain and,the.percentage .of the.crop that

would drop off the tree.before harvest In addition some consideration

had.to be given to the .loss of fruit due to the reduction in juice yield











since the production is measured in 90 pounds to .abox for all .processed

fruit.


Growth Pattern.Following the Freeze


The.reduced rate of growth following the freeze is illustrated

in Figures 1 through .4. Valencia oranges, since they were farthest from

date.of maturity, .suffered the greatest in reduced.harvest sizes. The

January 1 size has been used as the harvest size in all crop forecasting

work for Early and.Midseason oranges. Therefore, .this type had nearly

reached harvest size prior to the freeze. The January 1 average size

reached by Early and Midseason.oranges was 10.62 cubic inches whereas the

projected size used in.the December 1 forecast was 10.83 cubic inches.

(Figure 1). Valencia.oranges were projected to .reach an.average .harvest

size of 13.0 cubic inches in the December 1 forecast, however, the average

size on April 1 (which has been.used in all forecasts as average harvest

size for Valencias) was 10.80 cubic inches. The growth curves during the

freeze year 1957-58 is also shown in Figures 1 through 4. The Valencia

growth rate following the December, 1957 freeze was slowed down consider-

ably but some recovery was made at the end of the season, However, the

December, 1962 freeze caused an actual decline in the average size of

Valencias after the January 1 measurements (actually the data.for the

January 1 date were collected during the second, third and fourth weeks

of December, hence the reduction occurred from the freeze forward).

Several factors may have caused.this reduced size: (1) the larger oranges

may have been the ones that dropped, leaving the smaller ones on the tree,

(2) a certain amount of elongation of Valencias was .noted after the freeze




























,o
oj


12 0


11.5





10.5


10.0


9,5


9,0


8,5


8,0


7.5


7,0


0


'7 Year Average


.-0


Ii-/

/

1962-63


(0 = Harvest size

I I I I


projected in the December 1

I I I I I


J


Figure lo--Growth
Recent


A S 0 N D J F M
Month

Rates for Early and Midseason Oranges 1957-58,
7 Year Average,


A M


1962-63 and


1957-58


forecast)

I I






















16o0


15o0


Q 14o0


r13o0 7 Year Average


C 12,0 .*

41, -''O '
4l 11,0 .
1957-58

p0 % 1962-63
1000


0





6 0
7 8,- o-




( = Harvest size.projected in the December 1 forecast

0 I I I I I I
A S 0 N D J F M A M J
Month

Figure 2,--Growth Rates for Valencia Oranges.1957-58, 1962-63 and Recent 7 Year
Average



























0o .* 0
O,rO
OL


1957-58 .



0
9







t


. ** '


7 Year Average


/



N 1962-63


(0= Harvest

I I I I


A S 0 N


Figure 3.--Growth Rates for Seedy
Average.


size projected in the December 1 forecast)

I I I I I I I


D J F M A M J


D J F M A M J
Month

Grapefruit 1957-58, 1962-63 and Recent 7 Year


40.0-


35. O0


30. OH


P
/e'


p
*~~0
0~


25.01-


45.0






























1957-58



0*0





o .


7 Year Average


,o
O"(


1962-63

-^
1962-63


( = Harvest size projected in the December 1 forecast)

I I I I i I I I


A S 0 N D J F M A M J
Month


Figure 4.--Growth Rates for Seedless Grapefruit 1957-58, 1962-63
7 Year Average.


and Recent


40.01-


35.0


30.01-


25.01


20.0I-


15. 0-










and (3) the .loss.of juice.due to .drying may.have actually .caused many

oranges to shrink in size.

The growth rate.of .grapefruit .appeared not to have been

effected by the freeze. In.fact, the.harvest size.projected on Decem-

ber 1 was exceeded. .This .doesn't necessarily mean that the freeze did

not reduce the growth rate, rather it indicates that the .December 1

forecast of grapefruit.harvest .sizes may have been too low.


Droppage.Pattern .Following the Freeze


The droppage patterns.for the two.freeze years, (1957-58 and

1962-63) and a 3 year average are.shown in Figures 5 through .8. The

effect.of.the freeze on droppage is illustrated here. Up until Decem-

ber 1 the droppage.rate.of Early and.Midseason oranges was slightly

over 8 percent and-the projected.total.drop in.the December 1 forecast

was 14 percent.. The final droppage was 24 percent. This 24 percent

compared to.slightly over 15 percent following the .1957-58 freeze and

14.5 percent for the 3 year average. Valencia orange droppage during

January and.February.was.heavy,.although for a.few weeks following the

freeze the droppage remained about.normal. The droppage.rate was about

10 percent.up.until.December 1,.an additional.4.percent .dropped off

during.the month for a total.of 14 percent.up until.January 1. During

January along nearly 15 percent of the Valencias on tree September 1

dropped.and.another 14 percent during February. At the seasons' end
/
it was.estimated that.about.53 percent of.the Valencia oranges on tree

as.of September 1 had fallen-to.the ground., A.considerable amount of

the Early and.Midseason .oranges.that.dropped off the .tree were actually
































1962-63


3 Year Average


1957-58


5.0-


S(0= Projected droppage in the December 1 forecast
0 t I I I I I I I I I
A S 0 N D J F M A M J
Month

Figure 5,--Cumulative Monthly Droppage Rates for Early and Midseason Oranges
1957-58, 1962-63 and Recent 3 Year Average.


25.OL


20.01-


15.0


10.0-O





























/
I
1962-63 a;


I o
I a

/d


55.0


5000


45.0


40.0


35,0


30.0


25.0


20.0


15,0


10,0


5.0

A


( roec
*/


o
do (0)= Projected.droppage in .the .December 1 forecast)
I I I I I I I I I I I


S 0 N D J F M A M J J
Month

Figure.6.--Cumulative Monthly .Droppage Rates for Valencia Oranges 1957-58,
1962-63 and Recent 3 Year.Average


1957-58







-3 Year Average







18


e-0-
,O0


55.0


50.0


45.0


40.0


35.0


30.0


25.0


20.0


15.0


10.0


5.0


n


`%1957-58



,' 3 Year Average


S (0= Projected droppage in December 1 forecast)
I I I I I I I I I I


S 0 N D J F M A M J J
Month

Figure 7.--Cumulative Monthly Droppage Rates for Seedy Grapefruit, 1957-58,
1962-63 and Recent 3 Year.Average


4962

I






























.c-0
-o'


1962-63 I

/ 0
1 0


.o
. 0



" 1957-58


/ N' 3 Year Average



//


(0= Projected droppage in the December 1 forecast)
I I III IIi


S 0 N D J F M A M J J
Month


Figure 8.--Cumulative Monthly Droppage Rates for Seedless Grapefruit 1957-58,
1962-63 and Recent 3 Year Average.


25.0-


20.0


15.0I


10.01-


5.0-










processed.since .they had reached.maturity, and harvesting crews were

able to.pick them off the ground. However, this was.not the case for

Valencias as the major droppage.occurred before they would.pass maturity

tests,

Seedy grapefruit, with considerable production located in

interior areas hit by the freeze, showed an.end of.the season estimate

of droppage of 37 percent; compared to 24.percent during the 1957-58

freeze.and a.projected drop .of 19 percent in .the December 1 forecast.

Seedless grapefruit,..with considerable .production located on.the East

Coast.which .suffered.less freeze damage than.other areas, showed a

seasons' droppage of 22 percent; compared to a droppage of 18 percent

in 1957-58 and.a projecteddroppage of.17.percent in the December 1

forecast.


Other Factors Influencing Freeze Losses


In addition to.the loss due to reduced.growth.and droppage,

other factors reducing the size of.the citrus crop were (1) elimination

from failure to meet inspection standards.at processing and handling

plants, (2) failure to harvest groves that.were heavily damaged from

the.freeze and.(3) reduced juice.yields,.mentioned previously in the

case of.Valencia oranges.

The weekly average pounds of juice per 90 pound, box of oranges

for the 1961-62 and 1962-63 seasons at .all processing plants are shown

in .Figure 9, The weekly average for the 1961-62 season from the week

ending December 2 until the week ending April 28 varied from 48.3 to

51.8 pounds of juice per 90 pound-box The juice yield began to .decline




















54.0-


52.0 -


2 9 1623 30
December


6 13 20 27
January


3 1017 24 3 1017 24 31 7 14 2128
February March April
Weeks Ending


5 12 19 26 2 9 16
May June


Figure 9.--Weekly Average Pounds Juice Per Box of
Plants 1961-62 and 1962-63 Seasons.


Oranges Received at Processing


Source: Florida Citrus Mutual Market News Bulletin, 1961-62 and 1962-63 Seasons.


50.0 -


48.0-


46.0


44.0


42.0


40.0


38.0


36.0


34.0


0


%- 0 -- 01961-62












1962-63













II I I I I I I I I I I I I I I I I I I I I t I I I










immediately following the December, 1962 freeze and reached a low of

35.3 pounds inflate January. The increase from this week until the

week ending on February 10 indicated.the.harvesting of better quality

early and midseason oranges of lesser amount of cold damage. Likewise

the increase in juice yield during the Valencia season from a low in

mid-March until later April indicated the movement of the harvest of

the more severely damaged.fruit before the.harvest of the better yield-

ing fruit. In comparison with an assumed juice yield of 50 pounds per

box had.a freeze .not occurred, the estimated amount.of.reduction in

citrus production.due to reduced juice yields varied.from about 5 to

14 percent by weeks.

In addition to the physical volume and weight losses there

were considerable economic losses because many of the oranges .did not

show an increase in the .percent .soluble solids .after the .freeze. The

processor calculates.the value of, and pays for, a box of fruit based

on the pounds.of solids per box. Pounds solids is calculated by the

following procedure:

P =B xJ

P = Pounds solids per box
B = Percent soluble solids
J = Pounds juice per box

Hence .it is easily seen that if the pounds of juice ,and,the percent

solids decline the reduction in .the pounds.solids is multiplicative.

The weekly average percent.soluble solids of all fruit re-

ceived at processing plants ,for the 1961-62 and.the 1962-63 seasons

is shown in Figure 10. The dotted line is an.assumption of what the

readings would have been for 1962-63 if there had been no freeze and










the same differential.between.1961-62 and 1962-63 that existed prior

to the freeze would have continued throughout.the season.

The actual pounds solids.per box.calculated from.the pounds

juice.and percent.solids of Figures.9 and 10 is shown in-Figure 11.

The average.for the three weeks.of 1962 prior to the effect of the

freeze.was about .5.14 pounds .solids as compared-with about 5.45

pounds solids for the same three weeks in.1961-62. From this point

the.1962-63 season.declined.to a low of about 3.70 in .mid-March and

as undamaged fruit.from.the lower interior and East.Coast.moved into

the plants it increased.to,5.14 for the last.week of-any appreciable

movement in late.April. The 1961-62 season averaged.close .to ,6 pounds

solids all.year long.


Estimated.Components.of Fruit Losses


The equations.used in.crop forecasting were re-worked to

obtain anestimate at.the end of the.season which.contained.the actual

rather than earlier estimates of size and droppage.. Assuming.the Decem-

ber 1 forecasts.to be.accurate,.the.amount.of loss due to (1) lack of

attaining projected size, (2) increased droppage .and (3) other factors

were determined from re-working these .equations. These estimates,

shown.in Table .6,.are based on the'monthly surveys, hence.the abnormal

harvesting operations that.occurred during the.weeks within the months

of January.and February make it difficult to obtain.anything more than

rough approximations. However in most cases.the components of loss

estimated inthe.last three columns of Table 6 appear reasonable esti-

mates, (seedless ,grapefruit.appears to be an exception).






















/ --O- O

/
6


'I


/
1961-62 /
I


0-0-o-..


(Assumed 1962-63
had there been
no freeze)


I I I I I I I I I I I I I I I I I I I I I I


I I I I I


30 6 13 20 27
January


3 10 17 24 3 10 17 24 31
February March
Weeks Ending


7 1421 28
April


5 12 19 26 2 9 16
May June


Figure 10.--Weekly Average Percent Solids of Oranges Received.at Processing Plants
1961-62 and 1962-63 Seasons.
Source: Florida Citrus Mutual.Market News Bulletin, 1961-62 and 1962-63 Seasons.


13o0[-


I-


0o


12.0
4*



0




Cn






0



0
h


/

- / ,
0'


10o00-


. I I


2 9 1623
December





g'""






















,\


-0- i
0' b4~0-D
/

/


\ k


1961-62


















/ 1962-63


4. 0--


I I I I I


2 9 16 23 30
December


6 13 2027
January


3 10 17 24 3 10 17 24
February March
Weeks Endini


31'.7 14 2128 5 12 19
April May


Figure l.--Weekly Average Pounds Solids Per 90 Pound Box of Oranges Received
at Processing Plants 1961-62 and 1962-63 Seasons.
Source: Calculated.from Figures 9 and 10.


6,0--


A'-

4,


x
o
m 505
0


0
0
0
S5.0
H
cr
r,
O
04
g 4.


I-


I


26 2 9 16
June


... . . . t


.


. I l


Ilil l l i f i l l t i l l i l l










Table 6.--December 1, 1962 .Forecasts, Actual 1962-63 Production, Losses
Due to Freeze, and Componentsof Losses of the December, 1962 Freeze
Estimated.Components
December 1 Actual of Loss
Type Forecast Prod. Loss ue Reduced Drop- Other
Freeze
Size Ipage Factors
Million Million Million
Boxes Boxes Boxes Percent Percent Percent Percent
ORANGES:
Early and
Midseason 60.0 43.5 16.5 27.5 8.6 41.6 49.8
Valencias 56.0 29.0 27.0 48.2 18.4 67.7 13.9
Temples 4.5 2.0 2.5 55.6 10.8 58.5 30.7

GRAPEFRUIT:
Seedy 13.5 10.0 3.5 25.9 -- 76.1 33.9
Seedless 24.5 20.0 4.5 18.4 -- 23.2 76.8


Percentagewise, Temple oranges were the greatest hit by the

freeze as 55.6 percent of the December forecast was never harvested. This

loss was estimated to be due to 10.8 percent loss in lack of sizing, 58.5

percent due to droppage and 30.7 percent due .to other factors including

reduced juice yield. Valencia oranges .showed a .48.2 percent loss from the

December 1 forecast of 56.0 million boxes. This loss was estimated to be:

an 18.4 percent loss due to lack of sizing, 67.7 percent loss due to drop-

page, and 13.9 percent due to other factors.

Seedy grapefruit losses due to the freeze were 25.7 percent of

the December forecast with 76,1 percent of this loss due to droppage. The

76.8 percent of loss of seedless grapefruit due to other factors appears

abnormally high. However, the seedless grapefruit production was reduced

by only 18.4 percent of the December 1 forecast. A statistical analysis

of the droppage rate by type gave a relative standard error about 7 per-

cent for all types except seedless grapefruit which was 31 percent. This

analysis also indicates that the component of loss estimates in Table 6










is questionable for this type of grapefruit.


TREE LOSSES FROM DECEMBER FREEZE


A preliminary survey was conducted during May .13 to 22, 1963,

to evaluate the extent of the tree damage.from the December, 1962 freeze,

Additional evaluations will be made based on later and more detailed

surveys

The May survey was conducted along the pre-selected routes

which extend several hundred miles throughout the citrus area. Approx-

imately 170,000 rows of citrus fronted on the routes traveled during the

survey.

A summary of the findings is presented in Table 7, The no

significant damage category included from .no damage to minor twig damage;

minor to substantial.wood loss included all trees whose bearing surface

was estimated.to be between 50 and.90 percent of pre-freeze bearing sur-

face; major wood.loss included all trees whose bearing surface was esti-

mated to be between 10 and.50 percent of pre-freeze bearing surface.

Bearing Temple orange trees, with about 20 percent in the

Indian River area, showed 44 percent.not .significantly damaged, an addi-

tional 24 percent with bearing potential, and 8 percent showed no sign

of life,

Thirty-eight percent of the bearing Valencia trees showed no

significant damage.as compared to 25 percent of the early and midseason

types. Forty-six percent of the Valencias and 53 percent of the early

and midseason types had .some bearing surface for present production










available. Over half of the grapefruit trees escaped.with no damage,

due .largely to,the heavy plantings in.the Indian River area.


Table 7.--Florida Citrus Trees: Estimated .Tree Damage in Commercial
Groves Caused by Low Temperatures of December 11-14, 1962
Bearing Bearing Bearing Non-Bearing
Tree Oranges Grapefruit.. Tangerines Citrus
Damage No. of Percent No. of Percent No. of Percent No. of Percent
Categories Trees of Trees of Trees of Trees of
1962. Total 1962 Total 1962 Total 1962 Total
1,000 1,000 1,000 1,000
Trees Percent. Trees .Percent. Trees Percent Trees Percent

Trees with Bearing
Potential:

No Signifi-
cant Damage 8,932 32 3,235 53. 329 33 2,212 15

Minor to Sub-
stantial Wood
Loss 6,150 22 920 15 300 30 1,620 11

Major Wood
Loss.. 4,750 17 730 12 190 19 1,030 7

Other Trees:

Hatracked 5,030 18 920 15 90 9 740 5

Butt Cut 1,680 6. 180 3 40 4 6,200 42

No Apparent
Life 1 400 5, 120 2 50 5 2 950 20

Total: 27,942 100 6,105 100 999 100 14,752 100


Florida.Crop and.Livestock Reporting.Service,
Preliminary Tree Damage Report, May 29, 1963.


Florida Citrus,


Tables 8 and.9 contain a summary of the data by areas and age

groups for all oranges and all.grapefruit bearing trees.


Source:










Table 8.--Florida Oranges: Estimated Damage to Bearing Trees in
Commercial Groves Caused.by Low Temperatures of
December 11-14, 1962, by Age Groups and Areas
No Minor to Major No
Areas Significant Substantial .Wood Hatracked Butt Cut Apparent
Damage Wood Loss Loss Life
Percent Percent Percent Percent Percent Percent

All Bearing Trees
East Coast 96 3 *
Upper Interior 20 22 18 24 8 8
Lower Interior 43 26 17 9 3 2
West Coast 11 18 20 35 10 6

Trees 4 to 9 Years of Age
East Coast 99 1 *
Upper Interior 13 11 8 8 28 32
Lower Interior 42 21 13 7 9 8
West Coast 10 16 14 13 28 19

Trees 10 Years and Older
East Coast 96 3 *
Upper Interior 22 24 20 26 4 4
Lower Interior 44 27 18 9 1 1
West Coast 11 19 22 40 5 3


*Less than 1 percent.
Source: Florida Crop and Livestock Reporting Service,
Preliminary Tree Damage Report, May 29, 1963.


Florida Citrus


SEPTEMBER 1963 CONDITION OF SAMPLE GROVES
USED IN FRUIT COUNT SURVEYS


During August and September, survey crews made fruit counts

(limb count and frame count surveys) in a sample of groves in preparation

for the first crop forecast released on October 10, 1963. The sample

trees in these approximately 1,500 groves were classified according to

the following categories:

(1) No damage
(2) Damaged but unpruned
(3) Minor damaged but pruned
(4) Major damaged but pruned
(5) Hatracked
(6) Butt Cut










Table 9.--Florida Grapefruit: Estimated Damage to Bearing Trees in
Commercial Groves Caused by .Low Temperatures of
December 11-14, 1962, by Age Groups and Areas
No Minor to Major No
Areas Significant Substantial Wood Hatracked Butt Cut Apparent
Damage Wood Loss Loss Life
Percent Percent Percent Percent Percent Percent

All Bearing Trees
East Coast. 98 2 *
Upper Interior 21 27 21 25 3 3
Lower Interior 42 23 19 13 1 2
West Coast 18 7 13 45 10 7

Trees 4 to 9 Years of Age
East Coast 100 *
Upper Interior 29 10 9 5 27 20
Lower.Interior 39 27 4 12 17 1
West Coast 15 19 3 8 55

Trees 10 Years and Older
East Coast 98 2 *
Upper Interior 21 27 22 26 2 2
Lower Interior 42 23 19 13 1 2
West Coast 18 7 13 45 11 6


*Less than 1 percent.
Source: Florida Crop and.Livestock Reporting Service,
Preliminary Tree Damage Report, May 29, 1963o


Florida Citrus


One of the major items of interest in this classification was to

obtain a rough estimate .of the extent to which pruning operations had been

completed during the first summer following the freeze. Figure 12 includes

a summary of this data in.the percent of the trees in each.category.

Valencia.oranges in this survey showed 39 percent no damage as

compared to.the larger survey reported above for May of 38 percent0

Twenty-six percent of the.Valencia trees were in the damaged but unpruned

category (Figure 12), Twenty-eight percent of the early and midseason

trees were in the damaged.but.unpruned category, 35 percent of the seedy

and 18 percent of the seedless.grapefruit were in this category,


_ ___ I __ __I_


















Early & Midseason


Valencia


Seedy Grapefruit


Seedless Grapefruit


Tangerine
I KY///////>// I IIB

Temple
I S ,IIIITangeloil

Tangelo
I --- b l l f i | B B


0 10% 20% 30% 40% 50%


60% 70% 80% 90% 100%


LEGEND


No Damage


Rx\\\\\ q Y/////A\ l l l l l l


Damaged Minor Major Hatracked Butt Cut
Unpruned Pruned Pruned

Work Completed b Sepot,. 1963


Figure 12.--Classification of Fruit Count Sample Trees by Various Damage
Categories as of September, 1963,


I


|' ................................










Twenty-four percent of the Tangerine trees in the fruit count

survey were classified-no damage, 26 percent were classified major damage

but pruned, 20 percent minor damage but pruned and 15 percent damaged but

unpruned (Figure 12). Only 6 percent of the Tangelo trees were in the

damaged but unpruned category as compared with 27 percent pruned (major

and minor) and 42 percent undamaged. Only 9 percent of the Temple groves

were in the damaged but unpruned category as compared to 32 percent

undamaged.


SUMMARY


This report contains information and.analysis primarily of data

collected by the Florida Crop and Livestock Reporting Service concerning

citrus fruit and tree losses from the December, 1962 freeze. Two weeks

following the freeze a state-wide survey was conducted to determine the

extent of fruit damage. This survey indicated that only 7 percent of the

early and midseason oranges showed no apparent damage as compared to 32

percent for Valencias. Nearly 50 percent of the grapefruit showed no

damage. Other classifications of scoring the fruit were (1) damage at

1/4" cut, (2) damage at 1/2" cut, (3) major or minor damage at center

cut, and (4) rind breakdown.

Three surveys were conducted at two week intervals beginning

February 18-22 to determine the maturity test and yield factors of

Valencia oranges. These surveys indicated that soluble solids increased

very little but there was considerable decline in juice yields resulting

in reduced pounds solids per box. The average pounds solids of 123

groves on the February 18-22 survey was 4.81 and for the same 123 groves









on March 18-21 the pounds solids was 4,64.

The components of the loss in the size of the citrus crop due

to the freeze were estimated from the regular re-occurring surveys con-

ducted by the Florida Crop and Livestock Reporting Service. The total

loss of the Valencia crop was estimated to be 27 million boxes. This

loss was estimated to be 18.4 percent due to lack of attaining normal

harvest size, 67.7 percent due to excessive droppage, and 13.9 percent

due to other factors, largely, loss of juice. The total loss of the

early and midseason oranges was estimated at.16.5 million boxes down

from the pre-freeze estimate of 60 million boxes. This loss was esti-

mated to be 8.6 percent due to lack of attaining projected harvest size,

41.6 percent due to excessive droppage and 49.8 due to other factors

including juice loss.

Grapefruit attained projected sizes thus the estimated 8

million box loss, down from the December 1 estimate 38.0 million box

crop, was due to droppage, failure to harvest groves, juice loss and

failure to pass .inspection.

A preliminary survey was conducted in .May, 1963 to assess

tree losses from the freeze. This survey, like the fruit damage and

maturity test surveys was conducted along the survey routes, criss-

crossing the citrus areas. Approximately 170,000 rows of citrus

fronted on the routes traveled. This survey indicated that about 8

percent of all bearing trees in the Upper Interior, 2 percent in the

Lower Interior, 6 percent on the West Coast, and less than 1 percent

on the East Coast showed no apparent life. However, 20, 43, 11, and







34


96 percent respectively of the bearing trees in these four areas

escaped with no significant damage.

A survey in August and September, 1963 indicated that

considerable pruning of dead wood remained to be done.




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