Front Cover
 Title Page
 Front Matter
 Table of Contents

Title: Citrus industry of Florida
Full Citation
Permanent Link: http://ufdc.ufl.edu/UF00088908/00001
 Material Information
Title: Citrus industry of Florida
Physical Description: 199 p. : ill., map ; 23 cm.
Language: English
Creator: University of Florida
Camp, A. F ( Arthur Forrest ), 1896-
Publisher: Florida State Department of Agriculture
Place of Publication: Tallahassee, Fla.
Publication Date: 1945
Subject: Citrus fruit industry -- Florida   ( lcsh )
Fruit trade -- Florida   ( lcsh )
Genre: non-fiction   ( marcgt )
General Note: Cover-title.
General Note: Previous editions issued as Bulletin. Florida Department of Agriculture, new ser., no. 2
 Record Information
Bibliographic ID: UF00088908
Volume ID: VID00001
Source Institution: University of Florida
Holding Location: University of Florida
Rights Management: All rights reserved by the source institution and holding location.
Resource Identifier: ltuf - AJP7129
oclc - 41130732
alephbibnum - 001823118

Table of Contents
    Front Cover
        Front Cover
    Title Page
        Page 1
    Front Matter
        Page 2
    Table of Contents
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Full Text

11LJUUL)lti UV'


^^^^^^^^^^^^^^^^^^^^^^^^^H S~lIMP''



Citrus Grow:

A. F.
Vice-Director in Charge,



A. F.
Vice-Director in Charge,


Citrus 1

Secty.-Mgr., Florid,


Citrus F

L. G. MAcD(
Director of. Research, Florid,


Agencies Serving the



ing in Florida
Citrus Experiment Station


se Operation
Citrus Experiment Station





Citrus Commission


History ................. 5
Plantings in Florida by Counties . . ... 8
Production by Years . .......... 11
Citrus Production Compared to Other Fruits ... 15
Selecting a Grove Site ... ......... 17
Stocks . . . . . . . . 24
Varieties . . . . . . . . 29
Oranges . . . . . . . 30
Grapefruit ... ... ........ 34
Mandarins .............. 36
Limes and Lemons . .. ..... 37
Hybrid and Miscellaneous . ...... 38
Citrus Propagation . . . . . . 40
Seedbed . . . . . . . 40
Budding Methods . . ... . . . 44
Handling Budded Trees . . . . 58
Digging Nursery Trees . . . ... 59
Packing Nursery Stock for Shipment ..... 63
Top-working ............. 65
Inarching . . . . . . .. 74
Transplanting Large Trees . . ... 78
Planting Citrus Nursery Stock ... .... . 82
Land Preparation ........ .. ... 82
Spacing in Groves . . . ... . 82
Planting Methods . . . . ... 82
Caring for Young Grove Trees .... ... 85
Care of the Bearing Grove . . . ... 90
Cultivation . . . . . . .. 90
Fertilization .. ............. 92


PH Control . . .......... 97
Pruning . . . . . 99
Pest Control . ............. . 101
Irrigation . . . . . . 110
Cold Protection . . . . . 118
Production Costs . ............ 128
Cost of Producing a Young Grove . . . .. 129
Calendar for Grove Operations .. . . . 134
Dooryard Plantings . . . . . .. 135
Varieties and Stocks . . . .. .. 135
Fertilizing and Spraying . .. .. . .. 137

Packinghouse Operation ........... 141
Picking Methods ....... . . 144
Packinghouse Methods . . . . ... . 145
Grades ... . . .... 154
Grade Lowering Factors ..... . 156

Citrus Marketing . . . . 167

Citrus Processing . . . ..... 171
Canning . . . . 172
By-products . ..... .. .. .. .. 173

Agencies Serving the Citrus Industry .... . 187
State Department of Agriculture ... . 189
Citrus Commission. ............ 193
University of Florida ....... ..... 194
Florida State Plant Board ....... . 195


Vice-Director in Charge, Citrus Experiment Station


-"TRANGELY ENOUGH, citrus, which is today one of the major fruit
7 crops of the western hemisphere, is a native of the Orient and was
unknown in the new World until after its discovery by Columbus.
:ories about citrus fruit occur in the oldest Asiatic literature, where it
as evidently one of the major fruits, its development seemingly cen-
.ring in southeastern Asia. It was carried by slow stages across Persia
Europe. First to reach the Mediterranean area was the citron, which
mentioned in the very early European and Arabian literature. It was
allowedd by the sour or Seville orange and the lemon, but the dates of
leir introduction cannot be fixed accurately for any particular European
-ea. The citron was described by Theophrastus in 300 B. C. The sour
r bitter orange seems to have spread through the Mediterranean area
i the period from 500 A. D. to about 1100 A. D. with both the Arabs

L fl...~


topworked to !
groves. Somew
even became de.
of these wild tr
that oranges we
believe that or,
found in this co
introduced then
Early settler
around the Spa
citrus plantings.
Spaniards and (
as St. Augustinm
River.- After tl
settlers from th
received a sharia
the trees to the
ways of Florid
water transport;
days there were
roads so that tl
main channels i

sweet oranges a
hat later sweet
nizens of the wi]
*ees by early trav
ere natives of Fli
inges, grapefruit
untry before the
s in Florida deA
nish settlement
. By 1800 there
theirr settlers, pr.
e and around Ta
ie annexation of
e north steadily
p setback in 183
ground. Later p
a and along thi
nation to New Y
no railroads in
ie rivers and lal



institute some of the very early
ges appeared, and some of these
untry in Florida, and the discovery
gave rise to the common opinion
* There is no reason, however, to
even limes or lemons were ever
iards and other travelers of Europe

ed orange groves, and particularly
t. Augustine by 1579 there were
e numerous groves planted by the
ally along the coast at such points
Bay as well as along the St. Johns
rida by the United States in 1821
minded the groves. This expansion
ien a severe freeze killed many of
igs were scattered along the water-
ist where access could be had to
and other eastern ports. In those
ida and little in the way of other
connected with them served as the

rally, the development was most extensive around the seacoast and
i the northern part of the State along the St. Johns River south of
acksonville and extending up the Oklawaha River to the area in south-

... ... ,_ - L _ L i ... -1 _i . .. . . y ... .. ... .. . 'N i-


rt of
of gi
It was
at it I

elos, which are simil,
aica by Captain Shad
that time, and it is
xrr;inI- Crnmn th cih

IHLJ v ;


County Year Bearing Non-Bearing Total Bearing Non-Bearing To
Alachua 1940 63,002 4,725 67,727 4,489 261 4,j
Baker 1940 711 26 737 119 18 1
Bay 1941 258 66 324 119 43 1
Bradford 1940 2,697 808 3,505 164 40
Brevard 39-40 749,415 116,064 865,479 254,706 26,195 280,L
Broward 39-40 166,703 44,640 211,343 19,528 4,498 24,(
Jalhoun 1940 95 ............ 95 3
Charlotte 1940 61,400 4,905 66,305 17,502 65 17,1
Citrus 1939 56,609 6,827 63,436 6,478 219 6,J
Jlay 1940 5,147 1,012 6,159 733 115
Collier 1939 14,597 129 14,726 13,838 105 13,I
Columbia 40-41 1,424 139 1,563 159 54 1
Dade 38-39 188,644 31,707 220,351 265,687 12,282 277,1
DeSoto 40-41 437,116 16,853 453,969 95,665 586 96,1
Dixie 1940 486 ............ 486 52 ............
Duval 1939 29,078 7,803 36,881 3,617 1,181 4,1
Escambia 1941 346 12 358 82
Flagler 1939 18,785 1,332 20,117 1,377 58 1,'
Franklin 1940 188 ............ 188 23 ............
3adsden 1940 240 ............ 240 39 ............
3ilchrist 1940 272 ......... 272 21 ...........

aaes v1940 ,
[If 1940
Imilton 1941
Lrdee 40-41 574,
ndry 39-40 40,
rnando 1939 101,
ghlands 1941 589,
llsborough 38-39 1,069,
llmes 1941
lian River 37-39 322,
ckson 1940
rferson 1940
fayette 1940
ke 37-39 1,567,

184 .......... 184
351 29 380
824 36,011 610,835
798 1,127 41,925
648 6,492 108,140
551 40,068 629,619 3
137 114,526 1,183,663 2
1g 1 lg



32,738 31
12,946 1
25,372 6(
18,139 1,7L
36,288 6,7i

454,516 66,886 5.
36 ............
480,112 22,420 5'


"' ' '

" '

County Year Bearing Non-Bearing Total Bearing Non-Bearir
Lee 1939 210,200 4,520 214,720 207,79!9 153
Leon 1940 382 ............ 382 73 ............
Levy 1940 2,215 ........... 2,215 160 ............
Liberty 1940 112 ............ 112 4 ............
Madison 1940 405 ............ 405 44 6
Manatee 37-39 294,189 34,546 328,735 346,402 7,934
Marion 39-40 592,289 58,507 650,796 48,695 318
Martin 1938 65,201 8,839 74,040 33.359 1,616
M onroe 1940 3,994 ............ 3,994 2.023 ............
Nassau 1940 2,146 243 2,389 213 24
Okaloosa 1941 105 30 135 40 3
Okeechobee 1940 21,666 5,470 27.136 6,501 164
Orange 39-41 2,176,529 236,248 2,412,777 260,538 14,351
Osceola 36-39 282,649 26,031 308,680 65,155 464
Palm Beach 39-40 75,541 28,909 104,450 36,401 3,186
Pasco 37-38 412,259 130,840 543.099 105,705 6,101
Pinellas 36-39 474,547 22,676 497,223 555.489 14,588
Polk 39-41 3,640,137 283,791 3,923,928 1.860,521 17,733 1,
Putnam 39-40 292,042 29,625 321,667 29,682 463
Santa Rosa 1941 90 ............ 90 16 ............
Sarasota 37-39 169,007 14.215 183,222 78,627 2,584
Seminole 40-41 436,179 47,293 483,472 50.782 695
St. Johns 1939 41,273 3,456 44,729 3.789 258
St. Lucie 40-41 530,420 138,480 668,900 312.194 58,674
Sumter 1939 127,038 12,686 139,724 10.703 471
Suwanee 1941 1,291 184 1,475 130 29
Taylor 1940 496 ............ 496 31 ............
Union 1940 1,157 189 1,346 103 68
Volusia 38-39 827,473 83,005 910,478 97.40q 5,028
W akulla 1940 98 ............ 98 35 ............
Walton 1941 132 55 187 37 22
Washington 1941 354 15 369 44 3
TOTAL 16,751,586 2,086,677 18,838,263 6,418.278 279,580 6,
*Includes lemons, rough lemons, kumquats, etc.
Note: The figures given in the above tabulations include all trees inspe(
grove formation, in small plantings or back yards, and regardless of th
represent what are usually regarded as "commercial plantings."



(Based on figure of State
Pslat B3ard Aug. 15. 1941)

* 10,000 trees
0 100,000 trees


Fig. 1.-Distribution of commercial citrus in 'lorida.


duction of grapefruit gradually increased and in recent years has be.
come almost as big a factor in citrus production in Florida as the orange.
The production of citrus fruit has become the largest single factor
in the fruit business of the United States today, and now approxi-
mately equals the production of all other major fruits, including apples,
peaches, pears and grapes. In Table I will be found tree counts foi
the various categories of citrus in Florida to give the reader an idea as
to the extent of the industry, and in Figure 1 will be found a map

(Taken from H. Harold Hume's The Cultivation of Citrus Fruits)

Season Florida California
1886-87 1,260,000 840,560
1887-88 1,450,000 957,600
1888-89 1,950,000 1,067,040
1889-90 2,150,000 1,333,800
1890-91 2,450,000 1,541,280
1891-92 2,713,180 1,691,760
1892-93 3,450,000 2,255,680
1893-94 5,055,367 2,230,980
1894-95 2,808,187 1,908,360
1895-96 147,000 2,878,500
1896-97 218,379 2,793,000
1897-98 358,966 5,758,140
1898-99 252,000 3,933,380
1899-00 274,000 6,767,420
1900-01 352,600 9,156,860
1901-02 974,033 7,747,060
1902-03 1,147,491 8,921,220
1903-04 1,954,954 11,114,656
1904-05 2,961,192 11,559,542
1905-06 3,794,133 10,155,542
1906-07 3,801,101 11,388,029
1907-08 3,250,000 12,327,944
1908-09 4,634,000 15,460,912

UirrmnILivici I j -r AjtUIlULI UI


Oranges-All Tangerines Grapefruit-All
Crop Year (000 Boxes) (000 Boxes) (000 Boxes)

1909-10 1 5,300 1,100
1910-11 1 3,600 1,200
1911-12 1 3,950 1,150
1912-13 1 6,700 2,000
1913-14 1 6,200 2,200
1914-15 1 8,000 2,400
1915-16 1 6,500 2,400
1916-17 1 5,700 2,500
1917-18 1 4,000 2,000
1918-19 1 6,000 3,500
1919-20 7,550 450 5,900
1920-21 8,700 700 5,800
1921-22 7,850 550 6,700
1922-23 10,150 750 7,800
1923-24 13,150 550 8,500
1924-25 10,400 900 8,900
1925-26 9,500 700 7,600
1926-27 10,100 900 8,600
1927-28 8,650 850 7,500
1928-29 15,000 1,500 11,300
1929-30 8,950 850 8,300
1930-31 16,800 2,400 15,800
1931-32 12,200 2,000 10,700
1932-33 14,500 1,900 11,600
1933-34 15,900 2,000 10,900
1934-35 15,600 2,000 15,200
1935-36 15,900 2,100 11,500
1936-37 19,100 3,000 18,100
1937-38 23,900 2,300 14,600
1938-39 29,900 3,400 23,300
1939-40 25,600 2,400 15,900
1940-41 28,600 2,700 24,600
1941-42 27,200 2,100 19,200
1942-43 37,200 4,200 27,300
1943-44 2 46,000 3,600 31,000

Includes tangerines.
2 Preliminary.
Source: Division of Agricultural Statistics
Bureau of Agricultural Economics



Grapefruit-All Oranges-Ai
Crop Year Texas Arizona California California
(000 Boxes) (000 Boxes) (000 Boxes) (000 Boxes)
1909-10 19 12,239
1910-11 36 17,078
1911-12 64 15,273
1912-13 85 6,870
1913-14 107 19,688
1914-15 139 17,407
1915-16 159 17,147
1916-17 188 21,315
1917-18 227 8,267
1918-19 380 18,315
1919-20 3 29 363 16,632
1920-21 5 34 395 23,771
1921-22 8 35 360 14,021
1922-23 35 60 394 21,283
1923-24 65 95 363 24,153
1924-25 301 105 387 18,506
1925-26 200 105 600 24,200
1926-27 361 120 672 28,252
1927-28 524 176 720 22,737
1928-29 753 211 972 39,159
1929-30 1,550 365 1,000 21,195
1930-31 1,200 400 1,290 35,179
1931-32 2,600 450 1,431 34,658
1932-33 1,440 614 1,350 34,265
1933-34 1,200 800 1,772 28,439
1934-35 2,740 1,240 2,167 45,047
1935-36 2,780 1,800 2,267 32,809
1936-37 9,630 1,400 1,540 29,827
1937-38 11,840 2,750 1,943 45,914
1938-39 15,670 2,700 1,924 41,420
1939-40 14,400 2,900 1,992 44,425
1940-41 13,650 2,650 1,983 50,778
1941-42 14,500 3,380 3,181 52,155
1942-43 17,510 2,600 3,071 44,296
1943-44 17,500 4,000 3,179 51,268
Source: Division of Agricultural Statistics.
Bureau of Agricultural Economics


showing roughly the areas of concentrated citrus plantings. It should
be noted that this distribution map shows concentrations of citrus in
certain areas in which the soil and temperature conditions are most
favorable. In Tables II and III will be found a record of the pro-
duction of oranges, grapefruit, and tangerines for Florida, and atten-
tion is called to the effect of the freezes of 1894 and 1895 (Table II),
of 1917 and 1927 (Table III), and the negligible effect of the freeze
of January, 1940 (Table III), which emphasizes the progress that has
been made in eliminating cold areas and improving tree condition by
proper fertilization and spraying. In Table V the production of citrus
in the United States is compared with the production of other fruits
grown in the United States.
When it is considered that the production of citrus in the United
States is consumed largely outside of the bounds of the area in which
it is grown and consequently that almost all of the fruit must be
transported in some way from the grower to the consumer, the pro-
duction is amazing. Apples and other fruits may move extensively
to local markets with only a portion transported to distant markets,
while almost all of the citrus crop must be graded and packed in a
way that will permit its movement for hundreds of miles to the con-
suming centers. In a sense the citrus industry is more of a business
perhaps than any other fruit industry, and this is in a large measure
brought on by the fact that the areas in which it is grown are remote
from the consuming centers.
The reasons for the amazing development of the citrus industry


(Compiled by Dr. L. G. MacDowell of the
Florida Citrus Commission.)

Boxes Bushels Boxes Bushels
(000's) (000's) (000's) (000's)

California 43.6 61.0 37.2 52.2
Florida 37.2 59.5 18.9 30.2
Texas 2.8 4.5 1.2 1.9
Arizona and Louisiana 1.0 1.5 .5 .8
Total Oranges 126.5 85.2

Florida 4.2 6.7 2.35 3.76

r7Z. zt '7 1 A1 7 A 2 ?

ly history of the citrus growing industry.



Production Methods

In selecting a location for a citrus grove there are a number
things that have to be considered with care if the grove is to be prc
able. In the early development of the citrus industry of Florida se
tions were made largely on the basis of soil fertility because so li
was known about the problems of cold protection. Owing to the
astrous effects of freezes, however, the emphasis today is mainly
warmth of location and natural cold protection rather than soil fertile
However, the soil is extremely important and the following gen,
discussion of this problem is given in order that the prospective gro
may be informed on the basic facts involved.
In the early development of Florida, soils were more or less cla,
in certain general categories having to do with the terrain and v
the type of growth occurring on them, and three general types v
commonly considered as follows:
(1) FLATWOOD SOILS. There are the soils in the low, flat ar
usually underlaid with hardpan and on which there is a growth
pines and saw palmettos with occasional bayheads or small swar
places which usually produce a growth of cypress or similar wa
loving trees. These flatwood soils are not generally used for cii
because the hardpan is too close to the surface and as a result the
will either become saturated with water during the summer season
too dry during the dry season. There are a few exceptions, howe
and these are the slightly higher places in the flatwoods where
hardpan is sufficiently far down to eliminate it as a factor in tree groN
The earliest developments on the flatwoods were associated with ca
operations, and these higher locations were the places where the ca
pens were located and in which seedling citrus trees were plantec
shade for the cattle and as a source of revenue. These favorable li
tions occurred chiefly in the following soil series: Scranton, Bla
and Coxville, with limited developments on Portsmouth, Leon, and
Johns soils. These soils are naturally somewhat richer from a ferti
standpoint than the high sandy lands which will be discussed later
are frequently rather cold, and drainage for excess water must be i
vided in most cases. In large areas of flatwoods a slight differ
in elevation will result in a considerable increase in cold protect.
and this is taken advantage of in locating groves in such areas.
flatwood soils are more often used for cattle grazing or, where
drainage is good, for truck crop production, and the planting of ci
on them in recent years has not been very extensive.


(2) HAMMOCK SOILS. Hammock soils are found where the original
growth was predominantly hardwoods such as oak, hickory, and mag-
)lia; and in the coastal area cabbage palmettos are commonly numer-
is. It was in hammocks that a great deal of the early development
:curred and also where the sour orange grew to the best advantage.
hese lands are usually well supplied with organic matter and have a
able supply of moisture throughout the season. They have the dis-
Ivantage of usually being low and rather cold unless close to large
)dies of water, and this tends to offset the higher degree of fertility.
7hile there is a great deal of acreage on so-called hammock lands
day, developments on these soils have not been extensive in recent
*ars. Included in the hammock soils are the Gainesville, Parkwood,
id Orlando series and some of the better grades of Norfolk and
istis soils. Mainly this classification of hammock soils is not a good
ie as far as soils are concerned because it is more of an indication of
)od moisture conditions and high organic matter content than it is ;u
dication per se of a soil series or type.
(3) HIGH PINELANDS. These are the soils on which the greatest
cent development has occurred. They are generally very light sands
f low natural fertility on which grew pines and the various types
scrub or black-jack oaks. The type of growth was to a considerable
:tent determined by the degree of fertility and varied from a very
heavy stand of pines to very few pines with a considerable growth of
ack-jack oaks. These soils are very well drained but have a very
tallow top soil in which most of the fertility is concentrated and a
-ry poor sandy subsoil. Underlying the sand is usually a clay subsoil
it the depth at which it is found may vary from 20 inches to as much
100 feet. When the clay is closer to the top than seven feet it may
ive considerable effect upon the value of the soil for grove pur-
)ses but below that depth has little or no effect. The most common
,il series in this group is the Norfolk, which varies from a very
arse sand extremely low in organic matter (Norfolk Sand), com-
only called "black-jack oak land," through Norfolk fine sands of
Trying degrees of organic matter content, commonly classed as high
nelands, to the Norfolk fine sandy loams which support hammock
hardwood growth. While the lighter Norfolk soils were not widely
anted to citrus until comparatively recent years, they constitute the
ajor soil series used for citrus today. This is not because of their
rtility but because of their natural warmth due to their elevation and
insequent good air drainage. Fertility is very low except on the sandy
am types, and trees are produced mainly by the application of ferti-
zers and sprays rather than by means of any natural fertility that is
*esent in the soil. A somewhat similar soil that is closely allied with
orfolk and is found on the lower slopes and in knolls in the flat-
oods is the Blanton soil, but instead of a yellow sandy subsoil, it has
very pale sandy subsoil splotched with gray to grayish yellow. Blanton
ils are usually somewhat more difficult to handle as grove soils and

frequently are a little less well located as regards cold protection. The
Eustis soils on which pines were originally growing are likewise some-
what similar in characteristics to Norfolk soils but are generally of
higher fertility. The better grades of Eustis soils were mainly growing
_ _ i-L__ ii_._ _ -. ,.- __A l _-l^,-_ :_ I-- u ..

irtant, b

is some-
s of the

)n must,
:ion soil
ils from

ot stan
in a ve

cation foi
is, there !
as it is c
the region
I P.-q

oirs rrom lioriaa citrus proves, r la. Agi
-_T r ml- d,4i, P il-i Th A-. rrr W


Base Exch. Pounds Per Acre-Six-Ir
oil Sam- Depth pH Satu- Cap. Exchangeable Bases
cries ration m.e./
pies % 100 g. Ca Mg K Mn Zn

Min. 4.60 17.5 1.39 149 5 21 0.2 0.08
55 Surface Max. 6.59 100. 6.25 1240 121 270 17. 5.6
ilk Soil Aver. 5.56* 57.3 2.72 520 39 73 3.2 0.91
Min. 4.29 7.0 0.68 20 1 8 0.0 0.08
55 Subsoil Max. 5.89 48.2 3.04 212 27 68 5.3 0.96
Aver. 5.03 17.8 1.26 66 6 26 0.8 0.36

Min. 5.49 40.2 3.51 605 18 66 0.3 0.16
6 Surface Max. 6.19 75.0 4.70 1070 78 175 7.5 2.0
on Soil Aver. 5.75 59.4 4.02 812 47 110 3.3 0.80
Min. 4.49 7.6 1.70 40 2 31 0.1 0.16
6 Subsoil Max. 5.39 22.1 3.44 281 13 42 1.5 0.56
Aver. 4.90 17.3 2.25 126 7 36 0.8 0.32

Min. 5.64 51.2 2.84 485 34 56 1.7 0.24
5 Surface Max. 6.39 89.5 6.46 1460 83 208 8.5 1.4
s Soil Aver. 6.04 71.5 4.17 1001 56 150 3.9 0.54
Min. 5.00 17.1 1.56 81 6 28 1.0 0.16
5 Subsoil Max. 5.74 64.0 3.60 363 19 88 4.7 0.48
Aver. 5.38 36.7 2.32 263 12 62 2.6 0.24

Min. 6.00 77.5 3.24 880 54 73 0.7 0.08
2 Surface Max. 6.74 100. 5.65 2160 105 78 1.2 0.16
vood Soil Aver. 6.37 88.7 4.45 1520 79 76 0.9 0.12
Min. 4.54 5.9 0.92 65 5 30 0.1 0.08
3 Subsoil Max. 6.04 33.9 2.61 532 34 57 0.1 0.40
Av-,-r. 5.37 19.0 1.66 233 15 44 0.1 0.24

F 3 io

Fig', 3.--Portion of 5,000-acre g


but their elevation makes possible the drainage of this air to
rounding lower lands. The location, consequently, should nc
trapped or surrounded by higher areas which would prevent the na
drainage of cold air away from the grove location. Sometimes
cation may seem to have good air drainage to a lower location b
this lower area is surrounded by a ridge to form a "lake" of col
then the location may be unduly cold. Very careful consideration sl
be given to determining whether a definite location has adequate
Water protection is very important. Locations near the coas
valuable where the slope is to the water because of the moder;
effect of the gulf or ocean on the land immediately adjoining. I
lakes are also a very excellent aid in cold protection, providing
are very deep. Shallow lakes are likely to become very cold 1
cold winds of considerable duration are encountered and consequ
do not give as satisfactory cold protection. The cold winds come
the northwest and north, and locations on the south and south
sides of large lakes are particularly favorable as far as cold prote
is concerned. Also, the amount of area in lakes in a given local
important. One lake, even if fairly large, will not give a great de
protection, but if in a district there are a large number of lakes

Fig. 4.-Trees grown on good citrus land with liberal fertilizatio
and cultivation produce abundant crons.


stituting a very large percentage of the surface of the terrain, the
cold protection is considerable. An examination of the map will re-
veal that citrus production in Central Florida is to a very considerable
extent concentrated in those areas which have a large number of lakes
or are adjacent to the coast.
Information on prospective cold protection can usually be obtained
from a history of the district under consideration, and particularly
from the groves in that area. If there are a large number of groves
which have been in rather steady production in spite of cold waves, the
area is probably quite warm, but if only a few groves exist and these
have suffered from cold, it is probably cold although some small
areas may be warm. In addition to examining the topography, there-
fore, considerable attention should be given to investigating the past
history of the old groves in the vicinity with regard to cold effects
during major freezes, as this is one of the best guides to the relative
cold protection in any area.
C. NEARNESS TO MARKETS. In addition to considerations having
to do with soils and cold protection, some consideration should be given
to the matter of marketing fruit that is produced. Freight rates in-
crease as the grove area becomes more distant from the northern market,
and also it is easier to sell fruit that is close to large packinghouses
than where the groves are away from good roads and more or less in-
accessible. In any selection of a grove location some consideration
should be given to nearness to packinghouses and canneries and to
the reputation of the areas as a profitable producing area. Groves
located in areas where there are few packinghouses and no canneries
and where roads are bad for hauling will usually be less profitable and
more difficult to handle than groves in areas where the supplemental
facilities are good.

Citrus Stocks
When planting a new grove the question of what stock to use is
an important one because the stock selected should be adapted to the
particular soil on which the grove is to be planted and also to some
extent this selection is affected by the variety which is to be planted
and the type of market which it is proposed to use. Improper stocks
may make a grove unprofitable because of poor production or slowness
in coming into bearing, and in the case of some particular varieties
may make for an inferior quality of fruit which will not be useful in a
specialty market if such a market is to be used by the grower.
Considerable change has taken place in the attitude toward certain
stocks due to the changes in tree nutrition which have taken place
during the last 10 years, and this change in viewpoint has been so
great with regard to rough lemon stock that it is now the most widely
used stock, although a few years ago it was on the verge of being


discarded. For this reason the notes below should be read with con-
siderable care because they represent a change of viewpoint toward
certain stocks which has been brought on by changes in fertilizer and
spray practices within the last few years, while the older viewpoints
were based on practices which are not now widely used. Some further
changes of viewpoint are likely to develop as the changes in fertilizing
and spraying progress further, but the following notes will be found
useful for those who propose planting a new grove.
ROUGH LEMON STOCK (Citrus Limonia, Osbeck) : This is the most
widely used stock in Florida citrus groves at the present, although it
did not come into extensive use until sometime between 1905 and
1910. It gained its original popularity because it would produce a
tree very quickly on the light sandy soils of the higher ridges, which
soils had not been used to any extent prior to its introduction because
of the slowness with which stocks formerly used would produce trees
on such light soils. These soils, because of the warmth of their location,
offered the possibility of eliminating a great deal of the freeze hazard
in Florida citrus growing, and when a stock was found that would
grow trees quickly on such soils a tremendous development resulted.
The stock was particularly adapted to nursery work because it grew
so well and could be budded with great ease, and produced a satis-
factory nursery tree in a relatively short time. Also, in large scale grove
developments it grows very rapidly and comes into bearing at an early
age. For this reason it was particularly well adapted to promotional
development where it was desired to make a large scale showing as
soon as possible.
As the groves on the light sandy soils came into bearing, how-
ever, numerous difficulties developed, including a tendency for the
trees to bear in alternate years and to have a heavy loss of leaves dur-
ing the year when a heavy crop was being carried on the trees. Also,
the quality of the fruit was inferior, the fruit tending to have a coarse
thick skin and to be lacking in flavor. In oranges the color was very
poor. This difficulty was blamed on rough lemon stock and for a
number of years a search was conducted to find a substitute stock
without success. With the development of the use of the so-called
minor elements, it was found that much of the trouble with rough
lemon stock was due to mineral deficiencies, and when these were
corrected, difficulties in maintaining the trees in good condition dis-
appeared and the quality of fruit showed very great improvement.
While it is still possible to produce a better quality of fruit on sour
stock under comparable conditions of soil and fertilization, the very
heavy bearing of rough lemon stock, plus the fact that fruit on properly
fertilized trees on rough lemon stock is only slightly inferior to that
on sour stock, has resulted in a general return to favor of this stock.
This is understandable in view of the fact that it brings trees into
heavy production earlier than any other stock so far used and is the

-.liy JLV .W LI-- 1 11- 1, --- 11 llU C -81 I V7- 1 ,y .5-L 1-1 l-71- -
present rough lemon stock is recommended for all light sandy soils and
For all varieties of fruit grown on such soils with the exception of
:angerines, tangelos, and other similar specialty fruits when these are
to be grown exclusively for the fancy fruit market. It is not recom-

? ..3

Fig. 5.-Rough lemon fruits and foliage.

Irl 411\111~111~1 V1 ILUl~lrULIVI\Y


mended for any wet soils because it will not stand waterlogging
tle soil for any appreciable length of time; and because of its suscep
ability to foot rot. In cases where soils are marginal between hea
hammock and light sandy soils and where the soil is well draine
preference should be given to rough lemon stock over sour orange
any doubtful cases because of its very heavy production and its abili
to withstand drouth.
SOUR ORANGE STOCK (Citrus Aurantium, Linn): The second m(
widely planted stock in Florida is sour orange, and this is also one
the oldest stocks on which budded groves have been grown. As pi
viously mentioned, the sour orange was widely spread by the Spa
iards and Indians throughout Florida, and many wild sour oran
groves developed in the hammocks. Some of the very early budd
groves were produced by budding these wild sour orange trees
place in the hammock, and these groves were called natural grov
Later the sour or Seville orange was promoted widely as a stock becau
of its great resistance to foot rot and the very fine fruit which it pi
duces on heavy soils with a good supply of moisture. It produces
very fine quality of fruit and under favorable conditions fruits at
early age and gives very satisfactory production. It is not adapt
to very light sandy soils but will withstand a great deal of waterloggi.
of the soil and is generally recommended for heavy soils, include
the best grades of flatwoods, hammock, muck, and other soils whi
are subjected to occasional flooding. It is a particularly desirable stc
for tangerines, Temples, tangelos, and other similar specialty fru
because of the high quality of fruit produced, and in cases where t
soil is marginal between sandy and heavy, it may be preferred for tht
varieties, particularly where these varieties are to be used for special
markets where quality is of great importance. ,
SWEET ORANGE STOCK (Citrus sintensis, Osbeck): This stock v
extensively used early in the history of the citrus industry but v
largely discarded because of its susceptibility to foot rot and also 1
cause of the slowness with which trees budded on this stock came it
bearing. In recent years it was revived as a stock in the search foi
substitute for rough lemon, and considerable planting was done in t
early thirties on this stock on light sandy soils. With the change
fertilizer practices, however, it has largely been discarded because
is not well adapted to light sandy soils, suffers considerably fri
drouth, and trees budded on it are slow in coming into bearing. 'I
quality of fruit borne on trees budded on this stock is excellent 1
the production does not compare favorably with that on rough lemi
particularly in young trees, nor does its resistance to drouth on li)
sandy soils compare favorably. It is not used on heavy soils because
its susceptibility to foot rot. It is used to some extent on interme
ate soils as a stock for specialty fruits but is generally considered
ferior in this regard to sour orange stock.

AM1nIV1fN %jr AzI1Uk.,UL1 Un1





Fig. 6.--Seeds of various species of Citrus and Poncirus.

TRIFOLIATE ORANGE STOCK (Poncirus trifoliata, Raf.): The trifo-
: orange is used chiefly as a root stock for Satsuma oranges and kum-
ts. It is deciduous and highly resistant to cold. Seedling trees of
species are very thorny, and are relatively slow growers. The ad-
on of the evergreen top by budding, however, appears to increase
vigor of the root system, although there is usually some stunting
*he ton. Outside of the northern portion of the state. where it is


older groves have other varieties budded on it. Generally speaking
it is probably much better adapted to the northern section of Floria
than to the central and southern sections. Fruit from trees buddi
on this rootstock is usually of a very excellent quality and particular
GRAPEFRUIT STOCK (Citrus paradise, Macf.) : Grapefruit was usi
as a stock to a considerable extent several years ago but is very litt
used at present. Its use was probably the result of observations as
the vigorous growth of seedling grapefruit trees. In many cases (
lighter soils it has proved unsatisfactory as a stock due to difficulty
getting trees budded thereon to bear properly. On the heavier so
this may be overcome, at least partially, by increased fertilization b
on light soils this has not been very effective. It is less cold resista
than sour or sweet orange.
MISCELLANEOUS ROOTSTOCKS. A number of other rootstocks ha
been tried to some extent but have not come into wide use so far. T
Cleopatra mandarin has been widely recommended and tried durii
the last few years and within a few years more it will be possible
gain a fairly good idea as to its desirability from the existing plain
ings. It is a good grower, makes a good nursery tree, both as to uni,
and growth, and seems to be well adapted to the light soils, but has
tendency to make tops budded on it slow in coming into bearing.
Commercial lemon is frequently found as the rootstock of occasior
trees in groves presumably budded on rough lemon. The seed in thc
cases probably were mixed accidentally with the rough lemon seed,
it is not considered to be a desirable rootstock due to its lack of dise,
resistance and the short life of trees budded on it.
At present a number of hybrids such as the citranges are being tri
as rootstocks, primarily in the hope of finding a substitute for t
trifoliate orange. A number of these hybrids exceed the trifoliate oran
in vigor and make satisfactory unions, but it will take some time
determine their suitability in other respects.

Innumerable varieties of citrus have been developed in Florida, I
there has been a tendency to standardize on fewer varieties in the 1
30 years so that 'today new plantings are limited to relatively f
varieties. Most of the older varieties are now shipped with the modi
varieties which are most nearly like them and not under their origi.
name. For this reason only a few varieties will be described, and th
wishing to study the earlier varieties can consult "The Cultivation
Citrus Fruits" by H. Harold Hume for a check list of the other vai
ties. No attempt will be made in this bulletin to give technical desci
tions of varieties but mainly to outline their outstanding characterist


Varieties of oranges fall into three general classes: Early varieties
which will pass the maturity test, provided by law, during late October
d November; midseason varieties which are shipped during De-
mber, January, or February; and late varieties which are ready for
ipment about March 1st and are shipped up to early summer. Grape-
lit varieties are less well defined as to season but were formerly
.ssed as early and late varieties, although this classification has been
gely done away with through the shipping of Marsh Seedless during
e early season. There is not in grapefruit the distinct seasonal ripen
g that is recognized in oranges. A description of the standard corn
ercial varieties is given below:

PARSON BROWN is one of the older varieties, originating about 187E
a seedling grove at Webster which belonged to Parson Brown. It
.s widely planted following the freezes of 1894 and 1895. The fruit
of relatively large size, has 10 to 19 seed, and a fairly coarse tex-
red flesh and a deep yellow juice. The peel is slightly rough or
bbly, and tends to remain dark green rather late in the fall, al-
ough the color "breaks" easily in the coloring room. It is shipped
>stly in October and November but under modern cultural practices
s been found to carry well into December and January with im-
wement in quality during the prolonged period on the tree. The
e is very vigorous with a pronounced upright growth, easily grown
I quite resistant to cold. Production is heavy, and it is the most
Jely grown early orange.
HAMLIN is one of the newer early varieties. It originated in a grove
.nted in 1879 near Glenwood, Florida, but has been planted ex-
isively only in recent years. It is a rather small orange, slightly oval,
:h a very smooth and fine textured skin, usually seedless, although 1
5 seed may occur in occasional fruits. The fruit develops sweetness
ry early in the fall. When originally grown on rough lemon, the
[p tended to be dry and ricy, but this has been overcome by changes
fertilizing and spraying, and excellent quality fruit is now produced
rough lemon stock as well as on sour orange stock, and the fruit
I be held through January if fertilization and spraying are properly
ried out. The chief disadvantage is the small size of the fruit as
npared with the Parson Brown and the very tender skin which is
ily injured by sprays and adverse weather. This variety should never
sprayed with lime-sulfur during the summer or early fall months
a burn may result that will seriously reduce the grade. Production
very heavy and the tree very vigorous but slightly more suscept-
- to cold than Parson Brown. It is the most widely planted early
iety at present.

PINEAPPLE is the most widely grown midseason orange and is usu-
ally round or slightly oblate with 13 to 20 seed. It originated near Citra
and has been planted more widely than any other midseason or early
orange since the freezes of 1894 and 1895. It is noted for the very
deep red color of the peel when fully ripe and the rich flavor of the
juice. Production is heavy and, when not properly fertilized, the trees
have a tendency to dying back when a heavy crop is borne and a con-
sequent alternation in production. This characteristic can be com-
pletely overcome by proper culture. While it is probably the best
flavored orange grown in Florida, its chief disadvantage is the heavy
production of midseason fruit plus the fact that it contains 12 to 20
HOMOSASSA is a large midseason orange which was a selection from
a seedling grove and is like the fruit produced by many of the early
seedling groves in Florida. The fruit is usually large, orange-yellow
in color but not orange-red, is usually round or slightly oblate, peel and
flesh fairly coarse, but the flavor of the juice and pulp is exceptionally
good; seeds 20 to 24. It has not been planted extensively in recent
years because of its seediness but constitutes a very large acreage in
JAFFA is round to slightly oblong and is usually rather large in size
with an orange-red peel. It was imported into this country from Pales-
tine about 1885 and has been extensively planted on heavy soils. When
attempts were first made to cultivate it on light soils it suffered exces-
sively from so-called "blossom-end" or stylar-end rot. This seems to
have been overcome to a considerable extent in recent years and con-
siderable acreage has been planted within the last few years. The fruit
has an excellent flavor with abundant deep orange-colored juice and
only 6 to 9 seed. It usually passes the maturity test a little earlier
than the Pineapple but will hang on the tree satisfactorily throughout
midseason. The tree is very vigorous with a peculiar upright habit
of growth in which the branches tend to be upright rather than lateral
or nearly lateral as in other varieties. The leaves are also more thickly
placed on the twigs with a peculiar form of overlapping which tends
to distinguish it from other varieties. The tree is very resistant to cold.
Plantings have been increased during the last few years.
SEEDLINGS. In the early history of Florida, citrus production was
based very largely on extensive seedling groves, and while no con-
siderable acreage of seedlings has been planted for many years, the
seedling groves that are still in existence furnish a very substantial por-
tion of the tonnage of fruit. The fruit is usually large with a smooth
rind which is slightly more loose in relation to the pulp than is char-
acteristic of most budded varieties. The acid and sugar content of the
fruit is high and the juice of excellent quality, the number of seeds

aries but is usually 20 or more per fruit. Seedling groves are very
eavy and consistent producers until they are neglected and start to
decline. While it is unlikely that any considerable additional acreage
rill be planted, they still constitute a very large portion of midseason
TEMPLE. The Temple is listed here because it is usually shipped
s an orange, although it is probably a natural hybrid between a sweet
range and some variety of mandarin. It was found on the old Temple
propertyy at Winter Park and was first introduced to the trade by the
buckeye Nurseries in 1917. It is an oblate orange, usually tapering
lightly to the stem end; medium in size having a deep red color in
he rind and a deep orange-colored flesh and about 20 seeds. The
lavor is different from that of the ordinary sweet orange, and the
)ulp and juice have a pronounced aroma. The peel is usually thin
nd may be smooth or pebbly depending upon the fertilizer program
nd rootstock; it separates more easily from the pulp than is character-
stic of most Florida oranges but not quite so easily as the tangerine.
t is the finest orange in Florida for eating from the hand. Its season
s sliehtlv later than the ordinary midseason orange with the first fruits


tons ot stocks and soils. It constitutes the main crop ot late orank
in Florida.
LUE GIM GONG. This orange is one of the newer late varieti
and was introduced about 1912. It is thought to be the result of ha:
pollination of the Valencia with pollen from the Mediterranean swi
by a Chinese, Lue Gim Gong, who resided near DeLand. The vari(
has been presumed to be somewhat superior to the Valencia with mc
cold resistance in the tree and somewhat better color of fruit and wi
a longer season. As grown commercially it has been impossible
definitely separate it from the Valencia. The fruit is large and oblor
contains about 6 seed, and the flesh is a deep orange color and of go
quality. The season is the same as that of the Valencia.

While there are a great many varieties similar to those already (
scribed and which have been planted at various times, they will not
discussed in detail here because they are no longer commercially plants
Some varieties which are slightly different from the standard orang
however, are of interest. Most of these fall in rather definite classifi
tions which will be discussed briefly below:
BLOOD ORANGES. These constitute a group of varieties in whi
blood-red streaks develop in the flesh, sometimes as very fine ma.
ings on the segment walls and sometimes as definite red blotches
the segments. The amount of red is related to some extent to t
weather conditions and is more pronounced in cool winters. Thl
are no longer extensively planted but constituted a considerable ac
age at one time. Of the varieties planted, the Ruby Blood is most (
tensively grown. It is a small to medium, round to oblong orange; t
color of the peel in midseason is deep orange-red to red. The pt
is of very fine grain and of excellent quality and streaked with red
midseason; seeds about 11. It has been shipped as an early orar
but usually is classified as a midseason orange. Its quality is very sup
ior but it is frequently discriminated against on markets which are i
familiar with the red marking, and in recent years has usually be
shipped before the red markings develop. Other blood orange vat
ties which have been planted to some extent are the Maltese, SaL
Blood, and St. Michael. Blood oranges are seldom planted at presi
but are interesting as dooryard varieties for those who wish unusi
fruits of fine quality.
NAVELS. The Washington navel has never been very satisfact(
in Florida, although it is a standard commercial orange in Californ
In Florida is has a tendency to have a dry pulp, and in wet seasons wl
vegetative conditions are favorable may never be juicy. Because there
a demand for navels, various attempts have been made to collect stra


of navels which would fruit well under Florida conditions. One of
:he early strains of this type is the Surprise navel which is a medium.
sized early navel with a navel which usually does not protrude. It has
been very little planted but probably more so than any other variety
of navel in Florida up to recent years. At present a considerable mum-
ber of new varieties of navels have been selected and are being planted
.n a limited way. Some of these appear to have promise, but it is still
:oo early to determine definitely their commercial value. Most of them
ire seedless or nearly seedless, ripen early, and run from medium to
.arge size. Under favorable conditions they are of excellent quality
md have been sold extensively on the fancy fruit market. The peel is
usually thick with a very smooth external texture, and the fruit is
particularly good for eating from the hand as the pulp holds together
betterr than that of most Florida oranges.

The original seedling grapefruit groves in Florida produced fruits
with a large number of seeds, and innumerable selections of varieties
have been made from these groves in which the number of seeds varies
from 30 to 60 per fruit. Unfortunately, these varieties have not been
rery clear-cut in their characteristics, and considerable carelessness has
developed in their classification and segregation in groves so that it
s difficult to be certain of the origin of the strain in any particular
yrove. The Duncan was one of the earliest of these, and this name is
widely used today for budded seedy grapefruit, and while it was evi-
lently a distinct variety in the beginning, its distinction has been very
largely lost through the application of the name to many other strains.
otherr varieties which at one time were extensively planted are the
Walters, Silver Cluster (Hall), McCarty, and Excelsior, but the dif-
ferences between these varieties were insufficient to make classification
easy, and the names used by owners to classify the varieties in their
;roves are not always in strict accordance with the original descriptions.
For that reason there is more and more of a tendency to classify seedy
grapefruit as "Florida common" or seedy grapefruit and to omit the use
if a varietal name because classification of the fruit after it is picked
s impossible under present circumstances. The name Duncan is used by
nany packinghouses to cover all seedy grapefruit and about the only
eedy grapefruit that has any separation as a distinct variety at the present
ime is the McCarty, but even here the name is used to cover other strains
besidess the original one. For that reason no attempt will be made here to
separate the various seedy varieties which usually contain from 30 to 60
eed, are usually oblate in shape, though the shape varies with fertiliza-
ion and cultivation conditions. The tendency to bear fruit in clusters,
vhich has been used to classify fruit of certain varieties, is now known
o be controlled to a considerable extent by nutrition as the same strain

i knn~wn as Pink Marsh Seedless was extensively olant-

attempting to classify these into various groups botanically, a few
ie important varieties which are grown commercially are listed
)ANCY TANGERINE. This is the principal commercial variety of this
p in Florida and has been widely planted throughout the state.
fruit is oblate in shape, usually about 23/4 to 3 inches in lateral
eter, deep orange-red to red in color. It has a nippled base, 11
[ sections and usually about 14 seeds, although the seeds may vary
ly in number. The skin is very smooth and loose from the pulp,
as the fruit gets riper the pulp sometimes becomes entirely sepa-
from the peel. The pulp is very tender and the flavor rich, with
y definite aroma, somewhat spicy. The tree is round-headed with
what willowy branches so that under heavy cropping it sags down
', and unusually heavy crops may result in a great deal of splitting
e crotches. Generally, it is a very heavy bearer with a tendency to
ace too many small fruit. This variety is commonly known as the
!rine rather than the mandarin.
'here are a large number of other similar varieties, including the
o, Warnurco, Clementine, and Cleopatra, the latter having been
mainly as a rootstock.


KEY OR MEXICAN. This is a small acid lime commonly grown
throughout the West Indies and is known by various names, the Key
lime in Florida, the Mexican lime in Mexico, the Dominican lime in
Dominica, etc. It is a small, seedy lime, almost round, with a slight
nipple, seldom over 2 inches long and commonly smaller. The color
is a very light green to lemon yellow. The skin is very smooth, the
nipples are usually very short and small, and the base is very slightly
elevated where it attaches to the stem. It has about 10 sections with
very thin section walls and none to several seed, usually the latter. The
juice is very excellent in flavor and very acid, usually containing 7 or 8
percent citric acid. The tree is bushy, and usually not over 10 to 15
feet high, heavily covered with spines and having a more or less ever-
bearing habit where cold weather does not interfere. It was at one time
grown extensively on the Florida Keys south of Miami and on the
Keys along the gulf coast of Florida, but has not been very satisfactory
on the mainland, both because of sensitiveness to cold and diseases that
attack it and disfigure the fruit. Some varieties have been described
but in the main it is a collection of seedlings that are more or less alike,
and no particular varieties are planted commercially, though several
have been described and named.
TAHITI OR PERSIAN. This is a large oval lime, commonly 3 inches
long, shaped much like a lemon, with a very smooth skin, green pulp, and
almost always seedless. The iuice is very acid and of excellent flavor.

tangerine and disliked by some people


Another fruit of somewhat similar characteristics used as an orna
mental is included here, although it differs botanically. This is thl
Calamondin, which is a small fruit shaped like a tangerine but witl
very acid pulp. The tree grows tall, is well-formed with very beautiful
foliage, and bears a very heavy crop of yellow to orange fruit. It i
used mainly as an ornamental, although the fruit is used as a substitute,
for limes and lemons as well as occasionally for making marmalade.
There are a great many other groups of citrus and miscellaneous
varieties which might be mentioned but for a more complete listing
of these the reader is referred to "The Cultivation of Citrus Fruits" b,
H. Harold Hume. Among those which might be mentioned are th
citron of commerce, the shaddocks or pummelos, which are growl
commercially in the Orient and which resemble grapefruit, the various
limequats which are hybrids between limes and kumquats, and th.
numerous citranges which are hybrids between the so-called trifoliat
orange (Poncirus Trifoliata) and various sweet oranges. Many of thes
are interesting as trees for the dooryard but have no commercial valu
at the present time.


Citrus Propagation'
The growing of citrus fruits in Florida began with seedling trees.
As the industry developed the superiority of budded stock over the
seedling tree became apparent and led to the abandonment of the
seedling method of propagation. Fortunately, the propagation of citrus
by budding and grafting is very easy and its practice has extended be-
yond the nurseryman to the grove owner himself. Today many citrus
growers, even including those with only a few trees in their dooryards,
have acquired the skill necessary for the budding of nursery stock and
the topworking of older trees.
The discussion of nursery practice given herein is based on the best
commercial practices of today, together with knowledge gained in ex-
perimental work. A number of procedures are listed that are not in
general commercial use but which have a certain amount of interest to
growers at large.

The Seedbed
The seedbed should be located on good soil that is well drained and
capable of producing first-class growth of the seedlings. It should be
provided with irrigation, preferably of the overhead type, and some
nurserymen prefer to cover it with a lath shade, although this is not
necessary and the majority of seedbeds are planted in the open. The
lath shade has a tendency to increase the amount of seedling diseases
and makes the seedbed difficult to handle from this standpoint but
minimizes the moisture problem (see Figs. 7 and 8). The loca-
tion selected should be well protected from cold and the soil should
be well drained as this will reduce the trouble from seedling diseases.
A fertile soil is of course desirable but it is sometimes necessary to
sacrifice soil quality somewhat for the sake of good cold protection and
good drainage. It is also desirable to use new land whenever possible
and not to plant a bed the second time without letting it "lay-out" for
a while. The same rules apply to the selection of land for nursery rows.
A small amount of fertilizer is needed in making up the seedbed.
This fertilizer should have a high percentage of nitrogen, largely de-
rived from organic sources. The fertilizer should be added several
weeks before the seeds are planted and worked thoroughly into the soil.
Where only a small seedbed is desired the seeds are planted in rows
-wide enough for hand cultivation, but where a large number of seed-

Taken from: Camp. A. F. Citrus Propagation. Fla. Agri. Exp. Sta. Bul.
96, 1938.


lings are being grown the rows are laid out wide enough for horse
cultivation. The seeds are planted thickly in the row and are covered
with two to three inches of soil. Sour orange, sweet orange, grape-
fruit and rough lemon seeds are planted after the danger of frost is
over, as very young seedlings are killed when frozen to the ground.
Poncirus trifoliata seedlings are not completely killed by being frozen
off, but sprout up from below ground; consequently its seeds can be
planted whenever they are ready.
The number of days required for germination of citrus seeds will
depend upon the soil temperature and moisture and the condition of
the seeds when planted. Experiments with fresh seeds have shown
that the optimum soil temperature for germination is about 90 degrees F
Near the optimum temperature, fresh seeds will sometimes germinate
in two weeks but when the soil temperature is below 90 degrees F
a longer time is required for germination. In this connection atten
tion should be called to the fact that during the winter and spring the
soil temperature is much lower than that indicated as the optimufn
and the time required for germination is correspondingly longer. The
seedlings, however, are usually up in from three weeks to a month il
the soil has been kept moist and the weather is not too cold.
After the seedlings have come up it is necessary to cultivate suf
ficiently to keep down weeds and to water enough to keep the plant!
growing well but not so much as to cause damping-off fungi to attack
the seedlings. During the growing season two or three application:
of fertilizer having a high nitrogen content should be made. Before
the seedlings are removed from the seedbed, cultivation and fertiliza
tion should be stopped to allow the seedlings to harden up.
About one year from the September following the planting of th(
seed, making about 18 months in the seedbed, the seedlings are trans
planted to the nursery row for further growth and budding. Seedling!
are frequently transplanted after a much shorter period in the seedbec
but are harder to handle in the nursery row because of their small size
The seedlings can be removed by cutting the tap root 8 to 12 inche:
below the surface with a nursery spade, after which the seedlings car
be easily lifted. The seedbed should be well watered just before the
seedlings are removed. At least twice as many seedlings should bi
grown as it is intended to plant and only the best seedlings used.
In transplanting seedbed stock to the nursery row the soil is usually]
opened with a spade. Care should be practiced to prevent the doubling
up of roots, particularly the taproot, when planting. If necessary, prun,
back the roots before attempting to plant. Watering it the time o:
planting is highly desirable if the soil is even slightly dry.
The nursery rows are usually three to four feet apart and the tree
are planted about twelve inches apart in the row, the distance varying
;,, A .Frnt- n,,r-prip {(cp Fi l Generallv sneakinp, the row

. - . ., .

75~r ar ar





.-Citrus nursery seedbed under shade. (Courtesy Glen St. Mary Nurseries.)

would be wide enough to permit the use of a horse or mule in culti-
ting and the trees should be far enough apart in the row to permit
e free use of a hoe between the trees. The trees are grown in the
irsery row for about one year before being budded. Budding is usually
>ne in the fall-September, October and November-but may be
one also in the spring or summer.

Budding Nursery Stock
The standard method of propagating citrus nursery stock is by
adding. While the seedlings can be readily grafted by several dif-
rent methods, these are never used in practice because budding is so
uch simpler, quicker and more economical of budwood than is any
ethod of grafting. Citrus can be budded whenever the bark will
lip," that is, whenever it will separate readily from the wood. This
ndition exists during most of the spring, summer and fall, but in
Irsery practice it is customary to do most of the budding during the
II. Budding at this time is called dormant budding because the buds
not start into growth until the following spring. When the stock
large enough to bud in the fall a delay until spring will result in
ree to four weeks loss of growing time in the budded tree.
Budding in citrus is accomplished by the insertion of a shield-

Fig. 10.-Citrus seedlings in the nursery row r


produced entirely by
y easily happen that

.uIlnually praciULIL, suioC IIIIXIIg ui VancetLCs may occurLLI. 11 uuu LaKc
direct from parent trees are not obtainable in sufficient quantity, it is
betterr to bud a small block of nursery trees each year from suitable
hearingg trees and to use buds from these for larger blocks the follow-
ng year. The constant reference back to bearing trees in this way more
early approximates the ideal system of obtaining all buds from bear-
ng trees.
For the benefit of those just starting in the nursery business and
or those who are raising trees for their own groves, it should be
pointedd out that there is considerable variation in citrus varieties in
Florida. In selecting bearing trees as a source of budwood it is not
sufficient to take any tree that has been casually identified as belong-
ng to a variety. Budwood should be obtained from trees that have a
recordd of good production of true-to-type fruit and the greatest care
should be used in this selection. Trees that produce poor or freakish
fruit usually will transmit these characteristics to trees budded from
hem. Certain work has indicated also that gummosis might be trans-
nitted by budding, and as a precaution trees should not be used as
sources of budwood if they show any gummosis or have a history of
having been affected by this disease. It is well to remember at all
imes that the trees are not likely to be any better than the tree from
vhich the budwood was obtained.
For convenience in budding the budwood is usually cut into nieces




sphagnum moss and held in a cool place. If stored in sawdust it will
be necessary to repack occasionally.
A knife having a blade of the very finest steel and with a rounded
end is necessary. The blade should be made of steel comparable in quality
to razor steel and carefully ground and honed to a smooth, thin edge.
Many very careful workers prefer to finish sharpening the knife with
a strop similar to a razor strop. Unless the knife is of very fine quality
and very carefully sharpened, it is impossible to make smooth cuts and
to open up the bark without leaving loose shreds which interfere with
the insertion of the bud. Standard budding knives are commonly made
with a bone handle with a flat, wedged end for opening up the
bark where necessary, but the handle is seldom usedl by specialists in
Budding tape for wrapping the buds is made from thin bleached
muslin put up in rolls six to eight inches long, and one to two inches
in diameter. These are impregnated with a grafting wax that will not
harden. Of a large number of formulae for the wax, the one below,
taken from Hume's "Cultivation of Citrus Fruits," is considered very
satisfactory for use under Florida conditions:
R esin .......................................................................... 1 lb.
B eesw ax............................................................................ 4 lbs.
Raw pine gum............. .............. .......... 3 tbsps.
The grafting wax is heated over the fire until melted, a large iron
kettle generally being used, and the rolls are immersed in it until
thoroughly impregnated. The wax must not be too hot during the pro-
cedure and a good practice is to bring the wax to a boil so it can be
skimmed, then allow it to cool somewhat before immersing the rolls
of cloth. Plenty of time should be allowed so as to obtain thorough
penetration and the procedure can be helped by moving the rolls around
in the melted wax. If the rolls of cloth are too large, the wax will
not penetrate and the diameter, therefore, should be kept below two
inches. To secure better penetration, many workers tear the muslin in
36-inch squares and fold these into smaller squares for ease in handling
prior to impregnation. These are immersed in the melted wax and
unfolded with sticks to make sure of even penetration. The sheets are
then stretched on bamboo poles to drain and dry. After the cloth is
cool it can be torn off in strips the proper width for use, as needed.


Fig. 12.-One method of insertion.

Budding in the nursery usually is carried out on seedling trees froi
the size of a pencil up to an inch in diameter, but trees 1/2 inch to 3
inch caliper are most desirable; trees that are too small should I:
discarded. The trunk of the seedling is pruned clean of thorns an
limbs. ahead of the budder so as to save time, and the soil is scrape
limbs, ahead of the budder so as to save time, and the soil is scrape

'" if



ii. .-

,:.~ ii "'.~Z~,
; 5 ''


I.s 1

r / 1. :;1
~ r~ ,, ~

,r;; L


k~os~ ~



.7 I
~ Q

C 1
I, I ,~iS~*j
L .:

__ ___~__ ___ _ __ __1_____1___1


ith the

will give a shield-shaped piece of bark and wood about three-quarters
to one inch long with a flat, smooth cut surface. The bud should not
be scooped out as this will cause too much wood to be taken with the
bud. As the cut is finished, the thumb retains the bud on the blade of
the budding knife and at the lower end of the shield. Using this
method of holding the bud, with thumb and knife blade, the upper
end of the bud is inserted in the stock as in Fig. 14-D showing another
method of insertion. The bud shield when inserted is entirely beneath

o I



The type of budding here illustrated is described as inverted "T"
incision. In California the erect "T" is used, that is, the cross cut is
made at the top of the vertical cut instead of at the bottom as in the
Florida method. It is claimed that the inverted "T" method keeps out
moisture better and allows the bud to "drain," although the real reason
is probably to be found in custom, as either method will work satis-
factorily. When the erect "T" is used, the wrapping is started at the
top, that is, at the point of intersection of the two cuts.
The distance of the bud from the ground must be determined by
conditions under which the trees are to be used. Sweet orange scions
on sour orange stocks can be affected with foot rot if water or mud
stands above the bud union just as readily as seedling sweet oranges can
be attacked. Where the budded trees are to be planted in moist loca-
tions, the buds should be high above the ground but when they are
to be planted on drier lands the bud may be within two or three inches
of the ground to facilitate protection against cold by banking. Under
Florida conditions, the buds usually are placed as close to the soil as it
is convenient to work, that is two or three inches.
W/1M.n 41-, k.,- 1-rl. . -. lt- r--J11;- c- :, --. C -Q: -- -1-1-1-




~a ~Gk~lC~f~ '\

~ t~I~:

Ikq; ~
'' Rr~L~ .
..r "'
... '""
'r c -1; IP~L

..~' c;
a :.~~4~pr. .!. .

Fig. 16.-Nursery trees staked and tied-wooden stakes.

wooden stakes make it a practice to place the stake on the north side
of the scion to give a little protection from the north winds. The best
practice is to place the stake in the angle formed by the scion and the
stock. The stake is close to the scion, making training easy, and out
of the way of the cultivator. If the stake is placed on the opposite
side of the stock from the bud, the scion will be bent in training. When
the shoot is from one to three feet high, it is usually topped, thus
starting the formation of a framework for the tree. The height for
topping is determined by the operator to produce the type of tree
A large number of other methods of budding can be used but are
not ordinarily necessary in citrus. Some of these, such as ring or patch
budding, are particularly adapted to some trees that are budded with
considerable difficulty, usually due to a thick and brittle bark, and
which will not respond readily to shield budding, but these methods
are not used in citrus. Some variations of the shield bud are used in
working stocks that are too hard or in utilizing budwood that is too
angled to permit of the cutting of satisfactory shields of the usual
type. Two of these methods are illustrated in Fig. 18. These two
pictures represent types of what is called side budding, this method
being sometimes used on stocks that are too hard for the usual method

Fig- 17- il f bude tres (Cures Glen1 St.


^^^^^^^^_u^_^i H^---BiXi&lMK
^^^Hl ^HiSI
_*_ ^*Hj I^B^T
^^^^^^H^H^H ^^^HRtt-^1^
1 1 ^^^HIH) IHIB^R'
*< *

. -

keep down weeds and grass, a horse-drawn cultivator being used for
cultivating the middles and the rows being hoed out by hand. In the
fall cultivation is reduced so as to harden the trees before frost. The
amount and type of fertilizer will depend greatly on the type of soil.
A fertilizer analyzing 4 to 5 percent nitrogen, 6 to 8 percent phosphoric
acid and 4 to 6 percent potash is suitable. Three applications of fer-
tilizer per season should be made, the first just prior to the start of
growth in the spring, the second in June and the third in late Aug-
ust or early September. The amounts will vary from 500 to 1,500
pounds per acre per application, depending on the fertility of the soil.


The applications may be made broadcast and worked in with the cul-
tivator but usually the first is applied by "barring off" the rows (plow-
ing a furrow away from each side of the row with a small turning
plow) and placing the fertilizer in the furrow and covering it by plow-
ing the-soil back into the furrow. Too much fertilization and cultiva-
tion should be avoided as an excess tends to produce too rank and
soft a growth.
As pointed out previously, the scion must be tied to the stake from
time to time so that it will have a straight trunk. The height at which
it is to be topped to form the framework of the tree will depend on the
type of tree desired. Of late years the tendency has been to the grow-
ing of low-headed trees and the scions are usually topped at about 18
to 24 inches. In addition to the work of training the scion, sprout,
must be removed from both stock and scion occasionally. When the
tree has developed a strong trunk the stake is removed so that it wili
not be in the way when the trees are dug.
R,,AAl t-ro aor lln-,pA f-n ornvar a- Ipac nnP vepyr in fhp nirPerl




"""TO^ '*Ibji

g. 21.-Digging nursery trees. C, tree pruned back for digging. D. digging the
with a spade; the one on the left is cleaning off the leaves and twigs

Fig. 22.-Digging nursery trees. E, cutting taproot of tree with a spade; no
nursery tree; the worker's right hand holds the handle of the spade and wit]
Street up. G, the nursery tree lifted free of the soil; note the fine root system


packed in tightly with alternate layers of packing material and finally
covered with a layer of packing material and paper. The framing piece
is then nailed back in place and a piece of 1 inch by 3 inch placed
across the center of the open side and nailed to the sides to help hold
the trees in place. The side boards are then nailed on and the box
stood on end ready for receiving the burlap covering to protect the
tops of the trees (Fig. 23-B). The tops of the trees are now cov-
ered with burlap which is attached to the crate by means of lath strips
nailed to the top frame and securely sewed (Fig. 23-C). The crates
shown are usually 30 inches high but the side dimensions may vary
from 12 inches by 12 inches to much larger.
Smaller quantities of trees may be shipped in bales and three types
of bales are shown in Fig. 23-D. These vary from a paper covered bale
for mail order shipments to coverings of corrugated paper and wrap-
ping paper or burlap for express shipments. In all cases the trees are
packed in the proper packing material in much the same manner as
described for the crates. Regardless of the type of package the pack-


ps ~Bi~iPL~S~ar

ing must be done carefully to avoid drying out of the trees while i
transit. For local shipments, shingletoe is commonly used around ti
roots but trees to be shipped to distant points are usually packed i
sphagnum moss.

It is often desirable or necessary to top-work grove trees becau!
of cold damage or when it is desired to substitute a new variety f(
an undesirable one. Top-working large trees, while tedious, takes a(
vantage of the root system already present and brings a tree into pri
duction more quickly than can be done by planting young trees. Fr
quently it is desired to work over trees in yards so as to give add
tional varieties for home use and this is sometimes done by graftir
or budding more than one variety on the same tree. The commc
methods for the top-working of trees are: Budding sprouts or shoo
resulting from cutting back, budding old branches and then cuttir
them back, bark grafting or cleft grafting. The method used almo
exclusively in this state is the budding of new shoots, some of tl
work being done on the shoots produced when trees are "hatracked,
and some on sprouts from the rootstock produced when trees are ci
off at the bud union.
The budding of rootstock sprouts will be necessary when budd(
trees are killed to the bud by cold and the rebuilding of the orchai
depends on the rootstock sending up sprouts which can be budde,
In top-working relatively young trees this procedure is often mo:
convenient and efficient than reworking the tops since there are r
trunks and limbs left to produce sprouts of the original variety an
relatively little time is lost. Moreover, in the case of tangerines whi(
have brittle wood and a tendency to split in the limb crotches ar
Temple oranges which are dwarf in habit and also have brittle woo
the use of topworking on a framework is of doubtful value, both di
to the effect of the old top on the new top and also due to the dang,
of breaking up the framework after a heavy top of grapefruit or oranl
is developed on it. Even old trees of tangerine or Temple are cor
only worked over to other varieties by cutting back to the bud unio
The procedure for working over young trees (six years old or less
by this method, is to cut the tree off smoothly at or just below tl
bud union. It is usually desirable to start the cut on the side towal
which it is desired to have the tree fall, cutting about a fourth to
third through and then finishing it off with a cut from the other sic
so as to avoid excessive splitting of the stump. The stump is the
dressed to a smooth cut and it is desirable to cover it with a goc
wound dressing. The sprouts that come up are thinned to a suitab
number arising close to the stump. On a very small tree one spro
can be left, but on stumps more than two inches in diameter leave tv


left so that the stump will ultimately heal over well and several sprouts
also tend to grow together at the base and support each other. After
the sprouts have hardened up they can be budded, using the procedure
for nursery stock, but the work of budding should not be done too
soon. After the buds have started they will have to be staked and
trained. A nice piece of work of this type can be seen in Fig. 24.

.5 .


felled and staked so as to support r(
its are being worked.

two trees and the alternate middles kept clear while the first sprout:


Trees budded on Poncirus trifoliata should not be cut off at the
)ud, since this rootstock will frequently fail to send up sprouts. Other
:ommon rootstocks usually send up sprouts quite readily.

t -


b_ "*, .
i .-- 6



cut back about half the limbs and to work these over and get the buds
well started before cutting back the rest of the limbs. In doing this,
it is best to cut a large limb on one side to permit access to the middle
of the tree and then to cut off the central limbs (Fig. 27). After these
have been worked to the new variety and a good top started (one to
two years) the remainder of the old top can be cut back and worked
without danger of breaking pp the new top while removing the limbs.
This procedure is not usually followed as the grower is anxious to get
the new top into production and considers it too much delay. It has
the advantage, however, of keeping the root system in better condition
and producing some fruit during the period while the new top is being
developed. While this method is very seldom used its advantages are
such that it recommends itself highly as a general method of top-

,4 vAHdl&PMB

rlnisnea on me orner sioe, as mis prevents splining. nn alternative

C -It


is to cut the limb off one to three feet above the point where the final
cut is to be made and then to make the final cut at the proper point.
The cut surface should be smoothed over and painted with grafting
wax or a good wound dressing. The exposed framework and trunk
should be painted with whitewash to protect it from the sun, other-
wise the bark will be killed on the tops of the limbs. In addition, some
growers protect the framework and the new sprouts with some sort of
shade. This is usually a piece of sacking supported on some sticks tied
to the framework (Fig. 26).
Whitewashes which will stay on a tree trunk or limb in this climate
ire difficult to make. Formulae for several durable whitewashes may
be obtained from the Florida Agricultural Experiment Station at Gaines-
ville or from the United States Department of Agriculture. A very good
formula is as follows:
Q uicklim e ....................................50 Ibs.
XV7-1in _.1l.

LII 3FLLub Ilts VE Iia-lucllu up SUWILIL ly. IIIC llTg la tLt syscIII L[Inals
to push the growth vigorously and the buds may be easily "drowned"
if the wood is too soft. Generally, it is safer to lop the top of the
sprout after the bud has taken and to make the final cut later. It is also
good practice to snip off the tip of the sprout at the time the bud is put
in. After the buds have started it will usually be necessary to provide
some support to keep them from being broken off.
When trees are cut back it is common to have the new growth de-
velop "frenching." If any signs of frenching appear, it is wise to
spray the trees with the usual zinc spray recommended for this purpose.
Proper formulae for this purpose should be obtained from current spray
A number of other methods can be used in top-working but the
use of budding is generally preferred on account of the fact that a

great many workers can do good budding but very few are familial
with the methods of grafting adaptable to citrus. These other methods
are useful at times and for this reason a discussion of them will be
given here.
When working large limbs, budding can be used directly on the
limb if the workman is careful. In case the bark is reasonably soft and
pliable, some form of shield budding can be used as previously des-
cribed. Often the curved or angled incision will be found superior tc
the "T" for this purpose. When the bark is thick and will not "work"
without splitting, it can be shaved and scraped to remove the outer harc
layers and the inner bark left for "working." If the buds are slow tc
"take," a partial girdling of the limb above the bud or cutting back the
top of the branch will help. This sort of budding is difficult and noi
recommended for ordinary use.
Dn-l, fm *>rr r-r-C*r- 11r -- f n Nnr L'

tlon, "the parafin should be just hot enough to keep it melted; if too hc
it will injure the tissues of the plant.


r CC



Fig. 29.--Cleft grafting. A, splitting the stub down the side; this gives
smooth cut for insertion of scion. B, splitting the stub. C, inserting scions.
scions inserted and stub taped and ready for waxing.




that the cambium of the scion and the cambium of th a
f _ I .- _ 1 . 1,__ L ...... J 1.-- ..... -1.1- _.. .:i-L

:are held

Fig. 30.-Trees saved by inarching. A, Temple orange tree on rough lemon
ot inarched with Cleopatra Mandarin; the inarch at left was close to the
ound and of a fine type; fruit borne on limbs above the inarch showed favor-
le influence of new root system. B, old seedling orange tree attacked by
ot rot successfully inarched with sour orange.

ground as possible (Fig. 30-A), but where it is a matter of saving a
tree attacked by foot rot the work should be done well above the lesion
(Fig. 30-B). Foot rot is commonest on old seedling trees and under
such conditions sour orange seedlings are to be preferred for inarching
and sprouts from the sweet orange root should not be used as they are
susceptible to the disease. If the tree to be inarched is headed low, the
seedlings may be worked into the limbs instead of the trunk but it will
be desirable to trim the trees up as much as possible to let light into the
seedling while it is becoming established.
Inarching is accomplished by making an inverted "T' incision in the
trunk of the tree and opening the flaps of bark slightly with the wedge on
the budding knife. The sprout or seedling is then cut with a long slanting
cut at such a height that when it is inserted into the "T" slot the cut
surface will be entirely within the bark and in contact with the wood of
the trunk. The insertion is made by "springing" the stem of the seed-

"~IRLUO %jJ llkjW11N%.3 JiN U

/0 irLJnrn.LIV.LNI Vtjr 1 flflltL. LIlMrC

I i



S* "

1'^b^ ^^ ^ -.^ **

Fig. 31.-Iarched seedling put in at an angle to the axis of trunk, a
cedure that is not recommended
Fig. 31.--Inarehed seedling put in at an angle to the axis of trunk, a I:
cedure that is not recommended.

_1.41%U) kjK1UJWRINIkj UN rL-J1UNL)I

ling or sprout suttlciently so that the tip can be inserted under the flaps
of bark and when the stem is straightened the tip will come to the
proper position. As the stock tends to spring away from the trunk of

whole is then wrapped with budding tape, raffia or string to help hold
it in place and the wound sealed with grafting wax or paraffin (Fig.
The work will have to be done when the bark will slip and even
then more or less difficulty will be experienced in working the bark.
Scraping or shaving the bark to make it more pliable will help some-
what. If the work is done carefully and the wound thoroughly sealed,
it will usually "take" and after several weeks the wraps can be cut but
the seal of wax or paraffin should not be disturbed.
Variations of the above method have been employed but in general
most of these cause the wood of the stock and the wood of the trunk
or limbs to be at a sharp angle to each other (Fig. 31), and results do
not seem to be as good as with the above method. Observations indicate
that best results are obtained where the stock and trunk are nearly par-
allel. This may be the result of a more natural flow of sap in such


Transplanting Large Citrus Trees
The moving of large trees has become increasingly popular during
the last few years and considerable acreage has been planted in this way
When done on a considerable scale, operators advise that they cai
transplant 10 to 15-year-old trees at from $1.00 to $1.50 per tree. Whil
it involves considerable work, the large trees will come into bearingi
much sooner than young trees. Generally, however, the transplantini
of large trees is limited to replacements in groves and for yard plant
Large citrus trees can be transplanted very easily if the proper pre
cautions are taken, and there is practically no danger of failure. Th
amount of root system to be transplanted will depend upon the facili
ties for moving the trees and the trees should be dug with as little dam
age to the root system as possible. As soon as the tree is dug the root
should be protected from drying out by wet burlap or other covering,
and kept protected until planted. The new hole should be larg
enough to contain the root system easily and should be dug just before
the tree is planted so that it will not have a chance to dry out. If pos



new hole is excavated evenly to the depth of the trench used in remov-
ing the tree and a post hole digger or shovel used to make a hole in the
center of it for the taproot. When the tree is let down into this hole
the lower lateral roots will rest on undisturbed soil so that there will
be less tendency for the tree to settle later. (Fig. 35). There is also
less disturbance of the subsoil than in the ordinary methods of excava-
Trees can be moved during the winter when they are fairly dor-
mant, in which case care will have to be used in keeping them watered
during the dry spring weather. Trees can also be moved at the begin-
ning of the summer rainy season and will usually become established by
The amount that the top will have to be cut back will depend upon
the extent of the root system moved and the care taken in moving. If




Fig. 35.-Water being used to wash soil around the roots and thus avoic
air pockets. The use of plenty of water greatly enhances the possibility
of the tree surviving.

Planting and Care of Citrus Trees
The land on which young citrus trees are to be planted should be
cleared as far in advance as possible, plowed, and disked. If time per-
mits, it is usually planted with Crotalaria spectabilis or some other le-
guminous plant for at least one season before planting the young citrus
trees. The cover crop is either disked or plowed into the soil in the
fall. Usually Crotalaria spectabilis is used for the purpose, and after
it is grown for one year on the land it may be expected to produce at
least two more good crops in young groves by natural reseeding, after
which time it probably will not grow on light soils due to damping-
off fungi. The land should be as smooth as possible and well-prepared
before planting. Planting rough land which is full of old roots and
stumps will lead to difficulties in cultivating and where oaks have been
present on the land may result in the Oak Root fungus being transmitted
to the citrus trees unless sour orange, which is resistant to this disease,
is the stock used.
After these preparations, the land is usually laid off and staked for
planting, and the spacings commonly used in recent years have been 25
by 25 feet for oranges and this or 30 by 30 for grapefruit. This spac-
ing is proving to be too close on light soils and wider spacings such as
30 by 30 for oranges and 35 by 35 for grapefruit are excellent. In
older groves closer spacing was common, particularly 20 by. 20, but such
close spacing has been found disadvantageous as the grove became older
due to the crowding of the trees, and when this crowding occurred, it
was very difficult to maintain the grove in good condition or to produce
first-class fruit. Spacings such as 15 by 30 feet are very desirable where
the grower is willing to remove the alternate trees somewhere between
the tenth and fifteenth year, but unfortunately this frequently presents
too much of a mental hazard, and interlocking trees present a problem
when the grove passes 20 years of age. For that reason double plant-
ing is not widely recommended. Many other systems of planting have
been used at one time or another, but today either the square or rect-
angular spacing is used.
In large plantings it is commonly customary for the nursery selling
the trees to do the planting and sometimes to take care of the new trees
up to one year of age. In smaller plantings the trees must be cared
for by the owner himself, and while a great deal may be done in plant-
ing a few trees in a dooryard which will improve the growth of the
young trees, planting methods on a large commercial scale must be
relatively simple. Trees are planted to best advantage during the wint-
er, and probably the best period is during January and early February
up to the start of spring growth, but planting in the early summer is
quite common.
In commercial planting, the common method is for the laborer to
draw the soil away from the stake with a hoe to form a saucer around

II_________I_~_ __ _____________I



-~~EI _7WS~~

+r . b


-e i. 3
-Dr wig ir aw y ro te sak t frmabsnfrte ots Fg.31

.-Planting citrus trees in the field. Covering root system FTig. '7D. 1
by drawing up th, dirt \iith a iii-.

'" --

spread our in rllu auccr ariuuIu rlUC sLaK. I/j15. i~- 1. 1113 i1 "cUiL
in the lateral roots being in their natural position and not doubled up
or crumbled. When they are covered a basin is left around the tree for
water (Fig. 37-B). Trees are watered immediately after planting and
thereafter as necessary until they become established. In heavy soils a
hole may be dug in the customary way and a planting board used, but
in any event it is important not to have the roots any deeper than they
were in the nursery, to have the soil well-packed around the roots, and
the roots not doubled up or bent. Air pockets should be avoided, and
the tree should be watered as soon as planted. When steamed bone
meal is available, 2 pounds of it may be added to the dirt placed around
the roots, but raw bone meal or other organic nitrogenous materials
which are likely to heat should not be substituted for steamed bone
meal as their heating is likely to kill the root system.
If the trees have been planted in the winter, they will start to grow
with the spring flush of growth, at which time one pound of fertilizer
should be added to the soil around the tree, covering an area slightly
larger than the basin in which the roots were originally placed. In the
past it has been common to fertilize young trees only three times per
year, using rather scant quantities because of the danger of dieback
(copper deficiency). In recent years it has been found possible to
avoid this by using the so-called minor elements freely, and under such
conditions a tree may be grown very rapidly with the use of nutritional

p the manganese rapidly v

When such a program
lould be kept for scales,
nulsion. In such groves
ist as they are starting is

t all times is indicated when the growing is being rushed but the:-

I A I-- A -T TT - ~

j -I--- -

rapidity with which profitable bearing is reached usually makes this
extra care profitable.
Young trees are usually cultivated along the rows during the sum-
mer of the first two years in order to prevent the cover crop from
encroaching on the trees. A mule drawn cultivator or a small tractor
outfit may be used to cultivate a strip about 6 feet wide on either

Fig. 38.-Crotalaria covercrop in young grove. Note the cultivated tree rov

side of the row while the middle is allowed to grow Crotalaria oi
some other heavy-growing leguminous summer cover crop. No cultiva
tion should be carried on except along the rows to keep the weed:
and grass from encroaching on the trees. The cover crop in the mid
dies should be disked down in the fall to prevent it from holding
back the drainage of cold air.
A watch will have to be kept for gophers and salamanders as thesis
may do a great deal of damage to young trees. About November 1 th,
trees should be banked with clean sand free of organic matter to th,
height of about 12 inches in order to protect the bud and the large
part of the trunk against freezing. These banks should be pulle(
down just as soon as danger of cold is past as otherwise scalding o
the trunks may occur in warm spring weather. Where labor is avail
able it is well to wait to bank the trees until cold weather is expected(
in the fall, but where labor shortages exist it will have to be done ii
I T ..... L C -.. 47A lw rr-0

__ _

Nursery trees as they are delivered for planting usually have the
trunks cut back to about 24 inches. When planting it is common to
:ut them to a single trunk and thus remove all the framework. When
they start to grow the sprouts on the lower part of the trunks should
be rubbed off frequently so that the shoots on the upper part of the
trunk will form the framework of the tree. These are not thinned
unless they become unusually thick, but if the lower sprouts are not
rubbed off the upper sprouts will become weak and the trunk will
have to be cut back. Occasionally some thinning of the sprouts on the
upper part of the trunk is done in order to get a better formed top,
but this is not usually done and the tree is allowed to grow freely
and form a top naturally.
Young trees should be kept under close observation during the
first two or three years so that trees attacked by gophers or salamand-
ers may be promptly replaced, and also watch should be kept for scales
if the spray program listed above is followed, and oil spraying should
be taken care of promptly. There is also a caterpillar known as the
"Orange Dog" which eats the leaves on young trees very rapidly and
which must be picked off by hand.
By the time the trees have reached 4 or 5 years of age they should
bear a good crop if they have not been set back by cold or an irregular
program of cultivation or fertilization. At this time they should be
placed on the regular program for bearing trees.

L~~11I~~Trr( T\T1 1~~~rl1l~l~n

Fig. 39.-Young grove in second

Care of the Bearing Grove
The general cultivation practiced in citrus groves in Florida con
sists of allowing the cover crop to grow during the summer period
when there is plenty of rainfall and no cold hazard. Because of dif
ficulty in growing legumes for any length of time on most sandy Flor
ida soils, the cover crop usually consists of native grass and weed!
and grows profusely enough so that it may be mowed at least one
during the summer period or chopped with a cover crop choppe
which consists of a large drum on which is mounted a series of knive
(Fig. 40). The general purpose of cutting where a mower or chop
per is used is to chop off the cover crop enough that it will regrov
a second crop rather than go to seed. During the fall after the rains ar.
over the cover crop is either disked into the top soil or plowed under
The general purpose of this cultivation is to eliminate the com
petition for moisture during a period when the weather is dry and t(
eliminate a fire hazard as well as to eliminate ground cover whicl
might interfere with the drainage of cold air during freezes. Diskin
and plowing are used interchangeably for this purpose but disking i
a little cheaper. Plowing is usually done with a three-bottom plow se
to plow about 3 inches deep, but was formerly done with an 8 or 1(
inch plow pulled by a mule. An offset grove disk is used for disk
ing and on light soils is provided with spools or depth gauges to pre
vent it from going deeper than 3 inches. The disking need not bi
extensive but should incorporate the cover crop in the soil sufficiently
to eliminate the fire hazard. The fall fertilizer is usually applied be
fore the disking is finished and is worked into the soil by the disk
Where groves are plowed instead of disked, the fertilizer is usually]
applied after the plowing and may be worked in lightly with a dist
which smoothes up the plowing job which necessarily must be rougf
due to the interference of the trees. During the winter the Acme har
row is used if there are warm, moist spells in which weed growth
starts, as it is undesirable to have competition for moisture during th(
winter period. When the cover crop starts to grow at the end of the
spring drouth, about mid-May, cultivation is abandoned for the sum
mer as the destruction of the cover crop might result in a cover crof
failure for the year. It is always a little difficult to determine jusl
when to stop cultivation in the early summer, but usually cultivation
after the 15th of May is likely to be injurious if any rains have oc-
curred by that time.
It is very important that adequate cover crop be grown in all
Florida groves during the summer period to protect the soil from
the heat of the sun and also to maintain the organic matter content of
the soil. As nreviouslv mentioned these snils havP a vPrV In nr.

___ 1___~____ ^_ 1___________

).-Covercrop chopper used to break down the covercrop in July to obtain a


ganic matter content and this organic matter is being constantly lost
by oxidation. Cultivation during the summer period will greatly in
crease the loss and also prevent the replenishment of the soil with
organic matter. Every effort should be made to get a good stand of
cover crop in the grove during the summer period, and fertilizer i,
now applied generally to the middles, as well as around and undei
the trees, in order to encourage the growth of cover crops as much a!
possible. On most sandy soils, where organic matter is of great im-
portance, the legumes will only grow well for three for four years,
after which time they will usually fail to make a stand. However,
the natural growth of native grasses and various weeds will give ex-
cellent cover and a considerable amount of green manure. On new
lands, as previously mentioned, Crotalaria spectabilis or Crotalari4
striata may be grown as well as cowpeas and Alyce clover. On heavier
soils beggarweeds and other legumes will frequently grow year aftel
year. In bearing groves, legumes may be dangerous unless disked or
plowed early in the fall as pumpkin bugs breed in. them and may
transfer to the trees and injure the fruit when the cover crop is killed
by late disking or cold.
In former years it was the custom to hoe under the trees at least
once a year in order to kill the weeds and stir up the soil. This prac-
tice was abandoned in the early thirties due to the expense, and un-
fortunately in most cases no effort was made to cultivate under the
trees by offsetting the cultivation implements. As a result the soil
has become very dry under the trees in many groves and fails to wet
satisfactorily during the rains or during irrigation. This should be
taken into consideration and some hoeing should be done under the
trees to stir up the soil and thus make it more easily wettable or else
the ground under the trees should be cultivated by offsetting the disk
or Acme harrow.
In some. areas sod is used in the groves instead of cultivation, but
it is usually found that this necessitates an increased amount of ferti-
lizer as compared with a grove that is cultivated. However, this pro-
cedure can be followed successfully where there is a good supply of
soil moisture providing the grove does not have so much growth in
it as to create a fire hazard during dry weather. In general in most
locations in Florida it is desirable to cultivate the groves during the
Bearing citrus trees are fertilized three times per year on most of
the lighter soils, these applications being timed to be applied just
prior to or coincident with the three normal flushes of growth. Spring
fertilization is usually done in the latter part of January or early Feb-
ruary, the summer fertilization as soon as the summer rains have start-
ed in the latter part of May or early June, and the fall fertilization in

program have been suggested from these experiments:
N* P20O K.O MgO MnO CuO
% % % (Water Soluble) % %
3 or 4 6 or 8 6 or 8 2 or 3 1 1/2 or 1
Mixtures along this line or modifications thereof can be used at each

r 13
Is of

It is difficult to make recommendations concerning exact pound-
; but using fertilizers containing 4 percent nitrogen as a basis for
iputation, it is generally found that about 2 pounds of such ferti-

Fig. 41.Fertilizr spreader in operation. The two laborers who are stand

and the operator on the step at the back operates

- --

iVII- i tI a.. l iu .. ali. -.ai ..0ulliy flJJt WV/IJ- -UL -J l tJ all. ll 111 rLlC .l. I 1t
is better to follow a regular program than to vary it widely from one
application to the next.
While fertilizer was formerly applied by hand in a ring around
the tree, it is usually applied now from trunk to trunk and mechanical
spreaders are usually used. (Figs. 41 and 42). With many of these,
the distribution of fertilizer is much better in the middles than under
phn l-r C o it f- fr1 I ;1v< c0rn.-rir-it l-fc rnf hln nhrs I-A i4 ;

wings or tne pm control proDiem. rertinzers may De eimer pnysloiogic-

______~_ __ __ __ ____~__~

ally acid, basic or neutral; i.e., they may make the soil more acid
(lower the pH) or more alkaline (raise the pH) or not affect the pH
at all. This needs to be taken into account in dolomite applications.
In fact many fertilizers are made strongly basic with dolomite filler
and this reduces the amount of dolomite needed in the separate ap-
plication. Materials other than dolomite may be used for the purpose
of pH control but some modification of the fertilizer program will
have to be made to offset this. Ground calcium limestone may be
used, in which case the ratio of nitrogen to magnesium in the fertilizer
should be 1:1; that is to say, a fertilizer containing 4 percent nitrogen
should also contain 4 percent available magnesium. Basic slag may
be used, and if so, the same increase in magnesium will be necessary
but a reduction in phosphate applied should be made as basic slag
usually contains 7 to 10 per cent available phosphoric acid. These two
materials react very rapidly with the soil and may raise the pH too
high unless applied with care.
Nutritional Sprays.1 On most grove soils is has been found that
zinc does not give entirely satisfactory results when applied to the
soil either in the fertilizer or as a separate application, and for this
reason it is usually applied as a spray. Zinc is recommended in a dor-
mant spray combined with lime-sulfur and wettable sulfur which con-
trols rust mites as well as supplying zinc, or it may be combined with
the usual post-bloom copper spray. Copper is used with wettable sul-
fur in the post-bloom spray to supply nutritional copper and control
melanose. For a detailed outline of the spray program, the reader is
referred to the section on pest control.
Modifications of the fertilizer program due to soil variation. The
above outline of nutritional practices is given for the lighter soils
which have a pH normally below 6.0. In the coastal regions in par-
ticular and in some other areas, there are soils which, due to the cal-
cium carbonate in the soil, naturally have a very high pH, often as
high as 8.4 and commonly having pH's between 7.0 and 8.0. There
is also a considerable acreage or normally acid grove land which at vari-
ous times has been overlimed and due to residues of lime in the soii
has a pH of 6.5 to 7.5 instead of the customary acid reaction. On such
soils it is desirable to use manganese in the spray program either add-
ed to the dormant zinc spray or to the post-bloom copper spray and to
omit it from the fertilizer because of the inability to keep it available
in the soil at the higher pH. Also, on such soils it would be inad-
visable to use dolomite as the pH is already too high, and it is better
to use only a water soluble form of magnesium, keeping the percent-
age of magnesium in the fertilizer as high as the nitrogen. In some
cases it might even be desirable to use more magnesium than this.

1For up-to-date recommendations on spraying the reader is referred
to the Better Fruit Program, printed each year by the Florida Citrus Com-
mission. Copies may be obtained from the Citrus Commission in Lakeland
or from your County Agent.

are bearing a heavy crop, it may be omitted from the fertilizer, but in
case of doubt it is better to supply it.
There is also a considerable acreage of citrus on muck soils which
necessitate rather special fertilizer recommendations. Such soils are
very high in nitrogen but usually very deficient in copper, zinc, potash,
and phosphate, and if the pH of the soil is as high as is sometimes the
case in muck soils in Florida, manganese will also be deficient. Mag-
nesium is usually present in fairly adequate quantities but needs to
be supplemented in some cases. For these soils fertilizer mixtures such
as 2-8-10 or 0-10-10 may be desirable with liberal amounts of copper
added either in the fertilizer or separately and other elements added
such as manganese and magnesium as indicated by the condition of the
trees. On some muck soils zinc will give fairly good response when
applied to the soil at the rate of 1 to 2 pounds per tree per year, but
better results are usually obtained by means of the spray indicated in
the regular spray schedule.
On heavy soils of low pH such as the heavier flatwoods and ham-
mock soils in the coastal regions and in the northern part of the citrus
belt, the usual ratios of elements indicated for acid soils will be de-
sirable and should be combined with a regular spray schedule, but it
is not necessary to keep the pH of these soils as high as that of the
light soils, and a range around 5.00 to 5.50 will be found quite satis-

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