Everglades Station Mimeo Report 63-9 November 1962
Pre-Harvest Hints for Sugarcane Growers 1/
Victor E. Green, Jr. and Joseph R. Orsenigo _
It should be the goal of every producer of sugarcane to derive as much
profit as possible from his limited acreage. Two factors influence his return
per acre: 1) tons of cane per acre and, 2) amount of sugar in each ton-.. There-
fore, each grower should supply the mill, when it calls for-his cane, from fields
having the highest yields of millable stalks that are the highest in sucrose at
On plantations in sub-tropical areas where the same group of persons grow
and mill their own cane, it usually ensues that, while considering sucrose and
yield, the following factors operate to determine the order of harvest of the
variCus fields planted to cane:
1. The cane most subject to frost is harvested early.
2. The land coming out of stubble crops is harvested in time to permit
3. Plant cane (cane planted recently that has never been cut) is the
highest yielding and lowest in sucrose. Stubble crops are usually
harvested first; the plant crop later.
4. Early maturing-varieties are harvested before later maturing varie-
After considering these factors, the fields are harvested in an order
permitting a steady supply of cane so that the most profit will be made in the
field and in the factory.
Individual planters who do not own mills, but who supply factories owned
by others, are allotted milling privileges in turn. This may be on a "so many
trucks per day during the grinding season" basis or "so many days of using the
factory alone". More planning can be used by the producer on the "so many
trucks per day during the season" basis since he can harvest his fields in a
logical order over a period of time.
However, if a producer is-assigned the facilities of an entire ry7
his entire acreage will be harvested in only a few days. For insta' ., using
a 5000 ton-per-day mill that requires the equivalent of 100 acr, f 50-tons
per acre cane per day, the harvest season of a producer of 500, r es of 50op
cane would last only 5 days. ;
This mimeo will be of most use to persons growing sugarcane f e first / /
time. General guidelines herein can be refined to rules-of- .umb as in-
dividual growers gain experience. --, .
SAssociate Agronomist and Associate Horticulturist.
This mimeo is intended to serve as an aid to growers of sugarcane. Nothing
written herein should be used in litigation, or circumvention of rules,
regulations or laws under the sugar act, or in disputes with processors
over yields or quality in sugarcane.
Because of the time, expense and difficulty involved, sampling techniques
are necessarily employed in trying to estimate the potential yield of a field
of cane. Samples must be taken at random in the field to give as true an esti-
mate as possible. Samples taken in places that have no merit other than being
convenient will not be of much value. This includes outside rows, rows near
ditches, or rows that can be traversed easily.
The sample taken for determining the average stalk weight should be cut
as low, topped as low, and cleaned of leaves and other trash as if the sample
were representative of the mill run, which it should be.
Most cane in the Everglades is planted on rows 5 feet apart. Since an acre
contains 43,560 square feet, the length of an acre-row would be:
13,5 =8,712 feet
A good convenient sample would be one-hundredth acre, or about 87 feet. One
method of estimating the yield from a sample is as follows:
1. Count the millable stalks on 87 feet of row and record the count.
2. Cut a 10-stalk sample, cut off the top and strip the leaves. Weigh
the sample to nearest pound and divide by 10 (point off one place to
3. Enter the table on the left at the closest number of millable stalks
per 87 feet, to the nearest 20 stalks. Next, enter the table at the
top on the nearest stalk weight, to the nearest 0.2 pounds. The
figure in the table, where these two factors intersect, gives an
estimate of the yield. If more than one sample is taken, average
the values obtained.
Millable stalks per 87' of row = 246 Use 240
Sample weight = 34 lbs.
Therefore stalk weight = 3.4 lbs. Use 3.4
Therefore, the estimated yield, reading right from 240, and down from 3.4,
where the columns intersect is 41 tons per acre.
For those who prefer to use 100 feet of row for increased accuracy of the
estimate, a column on the extreme right of the table is furnished.
Weighing device The stake pockets of pickup trucks make convenient receptacles
in which to mount a metal frame to hold and hang scales for weighing samples.
The frame can be made of galvanized pipe stock for the upright onto which is
welded an arm made of flat steel stock, suitably braced. A hook made of steel
bar stock is welded to the brace, on which the scale will be hung.
Table 1. Table for estimating the yield of millable sugarcane per acre when the average number of
stalks per 87 feet or 100 feet of row is known and the average weight of the individual
stalks is known.
Approx. Sugarcane Yield, Tons/Acre Millable
Stalks per ------------------------Average weight per millable stalk Pounds-------------------------- Stalks per
87' Row 3.0 3.2 3.4 3.6 3.8 4.0 4.2 4.4 4.6 4.8 5.0 5.2 5.4 5.6 5.8 6.0 100' Row
140 21 22 24 25 27 28 29 31 32 34 35 36 38 39 41 42 161
160 24 26 27 29 30 32 34 35 37 38 40 42 43 45 46 48 184
180 27 29 31 32 34 36 38 40 41 43 45 47 49 50 52 54 207
200 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 230
220 33 35 37 40 42 44 46 48 51 53 55 57 59 62 64 66 253
240 36 38 41 43 46 48 50 53 55 58 60 62 65 67 70 72 276
260 39 42 44 47 49 52 55 57 60 62 65 68 70 73 75 78 299
280 42 45 48 50 53 56 59 62 64 67 70 73 76 78 81 84 322
300 45 48 51 54 57 60 63 66 69 72 75 78 81 84 87 90 345
320 48 51 54 58 61 64 67 70 74 77 80 83 86 90 368
340 51 54 58 61 65 68 71 75 78 82 85 88 391
360 54 58 61 65 68 72 76 79 83 86 90 414
380 57 61 65 68 72 76 80 84 87 437
60 64 68 72 76 8o 84 88 -
The arm and brace can be welded to steel pipe fitted with winged set screws
to allow vertical adjustment of the arm.
So that the center and middle of the 10-stalk bundle will not have to be
tied, a holding device made from a shaped section of 1/2-inch concrete-rein-
forcing rod is loaded with the stalks and the rod is suspended from the hook
of the milk scale. An eye in the middle of the holding device will prevent
slippage on the scale hook.
Front view before
' h to 5 feet apart- -
Bend side arms 900 (right angle) to plane of
holding device at "x"
Arms of the device
should be 4 to 5
Any good milk scale weighing up to 60 pounds can be used. The weight of
the rod, of course, must be subtracted from the weight of the stalks. This is
done automatically if the scale has two "hands" on the dial. The rod is placed
on the scale and a hand of one color is placed on zero. The net weight of the
cane,: in subsequent readings, is read on the other hand, usually of a different
This characteristic of sugarcane as regards the producer is determined
largely on the amount of sucrose in the stalks. The mill is interested also
in percent fiber, percent trash, and acidity of the juice. Fiber is largely
determined by variety. Acidity is an important factor following a freeze.
Sugar cannot be made from trash.
In Louisiana, producers may take samples for quality determination to the
factory that grinds their cane, where the samples are put through a small mill,
the efficiency of which has been correlated with the large mill.
Many of the Florida factories do not have small mills yet, making it
impractical to obtain information, short of running a rather large amount of
cane through to obtain crusher juice. Therefore, growers must depend on hand
refractometers to estimate the quality of their cane.
A few definitions seem pertinent to a discussion of quality. These
definitions are essentially those approved by the International Society of
Sugarcane Technologists' Special Committee on Uniformity in Reporting Factory
Data, 1955, numbered by them.
2. Field Trash. The leaves, tops, dead stalks, roots, soil, etc. delivered
at the factory with the clean cane.
3. Fiber. The dry, water-insoluble matter in the cane.
5. Pol. The value determined by direct or single polarization of the normal
weight solution in a saccharimeter.
6. Sucrose. The pure chemical compound of that name, also known as cane sugar.
7. Brix. The brix of a solution is the concentration of a solution of pure
sucrose in water (expressed as parts by weight of sucrose per 100 parts by
weight of solution) having the same density as the solution at the same
temperature. For an impure solution the Brix represents the apparent per-
centage of solid matter as determined by a densimetric method. If refrac-
tive index (hand refractometer) be adopted instead of density (Brix hydro-
meter) as a basis of comparison, the value derived is known as Refracto-
meter Brix. Brix readings parallel but do not equal sucrose content of
Rendement This is a term that growers will be exposed to, which needs some
comment upon. It is no longer in use or on the recommended list of calculated
figures drawn up by the Special Committee on Uniformity in Reporting Factory
Data of the International Society of Sugar cane Technologists, but its use
seems to be widespread and persistent. Phonetically, it is "Rand-van".
Generally, rendement denotes the number of pounds of sugar recoverable from
100 pounds of millable cane. It can also be thought of as "yield percent
cane". This is the only reason for putting it on a 100 pound basis.
For example, if a mill has ground 80,000 tons of cane in a season and has
made 8,000 tons of sugar, their rendement thus far for the season would be
According to the strict: definition-
80,000 x 2000
8000 x 2000
A few definitions from the. United States Code, Title 7, Chapter .VII, Part
873 Sugarcane; Florida from the Federal Register of November 2, 1961, .their
numbers, also apply.
873.14(a)(4) Net sugarcane means the gross weight of the sugarcane as delivered
by a producer to a processor minus a deduction for trash of, 4 percent. '
873.14(a)(5) Standard sugarcane means sugarcane containing 12.5 percent sucrose
in the normal juice.
873.14(a)(7) Salvage sugarcane means ,sugarcane :containing less than 9.5: percent
sucrose in the normal juice.
NOTE: Normal Juice, as defined in the Cane Sugar Handbook, Spencer-Meade, 7th
Ed., is the juice extracted by dry milling, -without maceration water being -
applied.. "' '
SThe calculation of'normal juice sucrose is' made from the density of the
crusher juice and the purity of the mixed (diluted) juice. :'
873'.14(a)(6) Average percent sucrose in normal juice means the percentage deter-
mined by multiplying the seasons' average percent sucrose in crusher juice (by
direct analysis) of the producers sugarcane by either:
I. the ratio of' the average normal juice sucrose for-all Florida mills to the
average crusher.juice sucrose for all such mills during the most recent'5:years.
II. the 1961 crop ratio of the average' normal juice sucrdse to 'the average :
normal juice sucrose and'shall :uniformly use the method selected throughout
the crop. -
A dry milling factor is obtained by running dry milling tests under
government supervision. This factor is calculated by dividing the mixed
juice (the juice sent from the crushing plant to the boiling house) brix by
the crusher juice (to which no water has benn added at the crushers) brix, for
Mixed juice brix 15.0%
Crusher juice brix 16.0%
j-. = .937 or .94 dry milling factor
% Purity = scrosx-100
Brix of the normal juice = average crusher juice brix x dry milling factor.
Sucrose of the normal juice = normal juice brix x mixed juice purity
These definitions and examples show the complexity and detail that are
necessary to insure the processor a fair return, to establish factors in milling
and to comply with government regulations.
873.14(b)(2) states that net sugarcane (except salvage sugarcane) shall be con-
verted to standard sugarcane by multiplying the total quantity of net sugarcane
delivered by each producer by an applicable quality factor, using 12.5 percent
average sucrose in the normal juice as the base with a quality factor of 1.00.
For each increase or decrease of 0.5 percent sucrose, the factor increases
(premium) or decreases (discount) by 0.05.
ESTIMATING QUALITY IN THE FIELD
Hand refractometers, available locally, are small, convenient instruments
for estimation of sugarcane quality. They are refractive devices that give a
direct reading of the total soluble solids (mostly sucrose) in juice. To use
one, merely squeeze a few drops.of juice from a joint near the center of the
stalk and place on the glass prism. A pair of pliers can be used to extract
the juice.With the prism cover closed, the user looks through the adjustable
eyepiece and locates a dividing line crossing the scale and reads the percent
brix directly where the shaded area meets the unshaded area. A temperature
scale is not provided on the simpler, inexpensive instruments, nor is it
necessary. This is because of the following factors: 1) no two joints of
cane are likely to give the same reading on a single stalk, 2) no two stalks
in a field are likely to give the same readings, and 3) the readings are
relative and do not require exactness.
Readings taken at the bottom, middle and top of the stalk give an indica-
tion as to ripeness of the cane. For example, if readings from bottom to top
were 14.2, 10.6 and 6.8, the cane is green and should be allowed to mature.
If the readings were 18.6, 17.0 and 13.5, the cane is mature and ready.to
Refractometer readings give an indication of topping height before cane
is sent to the factory. Besides being low in sucrose, cane tops contain a
large amount of glucose and water. This dilutes the juice un-necessarily,
the glucose ends up in the molasses, and might prevent crystallization of
some of the sucrose.
TRASH AND ITS DETERMINATION
Trash was defined earlier, and is essentially anything accompanying the
millable portion of sugarcane to the factory, from which sugar cannot be made.
Besides, if the trash is absorbent, sugar is added to the trash in the crushers,
and additional loss is encountered. Also trash is objectional in that it is
expensive to transport the trash to the factory and to grind the trash, it
increases depreciation of the crushers, it reduces the purity of the juice, it
overworks the clarifiers, it slows down the grinding season and it adds the job
of taking trash samples and determining percent trash. Bianchi and Keller
(L.S.U. Eng. Exp. Sta. Bul. 28) estimated that clean, fresh cane instead of
the cane then coming to the mills of Louisiana in 1951 would have resulted in
a saving to the industry of over six million dollars. The loss divided among
the 47 factories was over $127,000 per factory.
The processor is authorized to deduct from the weight of cane delivered
by a producer the weight of trash exceeding 4 percent, but this does not com-
pensate for mill losses due to trash in the millable cane.
The exact amount of trash in cane is difficult to determine due to the
difficulty of sampling. A sample large enough to be representative must be
taken. There is no standard sample size in use in the industry. If all cane
were delivered to a mill in carts or trucks of the same size, a standard size
sample would be possible. For example, if cane were delivered in 20 ton trucks,
a 50 pound sample for trash may be adequate.
Sample weight = 50 lbs. Weigh.
Separate from the millable stalks all tops, green and dry leaves and leaf-
sheaths, weeds, grass, soil, etc. Weigh. If the trash weighs 4 pounds:
T = .08 x 100 for percent = 8% trash
-5 x= 50X = 400 X = 8% trash
The composition of trash in Florida cane will differ from Louisiana and
other areas, largely because of practices peculiar to Florida conditions. The
muck and sand of Florida will not stick to the cane as do the heavy clay soils
of Louisiana. As a rule, Louisiana cane is cut during a wetter season than
that in Florida, adding to the soil problem. Florida cane is burned standing,
is largely hand cut, and will be largely fieldchopped and not chopped only
between the carrier and the crushing mill.
Two innovations might prove useful if developed economically:
1. Pre-harvest dessication of the green tops with chemicals.
2. Blower and duct attachments to the field loader-chopper to remove muck
and loosely-adhering leaves and sheathes. A blower will not add dilution to
the juice as would wash water on the carrier.
Conditional payment for sugarcane producers.-
Besides the payment to the producer made by the processor of sugarcane, the
federal government makes payment to sugarcane producers. It is conditional in
that provided the producer complies with the rules and regulations of sugar
legislation, he receives a check for a certain amount of money, depending on
the quantity and quality of the cane that went through the mill from his farm.
It provides an incentive to growers to adjust their production to established
quotas and carryover sugar needs. Besides the prevention of child labor, the
payment helps give growers adequate income while assuring them and their field
workers a fair share of returns from the sugar industry.
This means that growers must pay field workers in full at rates not less
than those determined by the Secretary of Agriculture to be fair and reason-
able (after hearings open to growers).
The conditional payments are calculated from tables made up by the Sugar
Division of the ASCS in Washington and data collected from the farms and fac-
tories where the sugarcane was grown and milled. The state and county ASC
Committees are responsible for the local administration of the payments.
The base rate of payment is 80 cents per hundred pounds of raw sugar pro-
duced up to 350 short tons, or up to 350 x 16.00/ton = $5600. Assuming an
average yield of 40 tons of millable cane per acre from which 200 pounds of
sugar are recoverable per ton, an average acre would yield 4 tons of sugar.
Therefore, for each acre up to 87.5, that is 350 / 4, the grower will receive
16 x 4 = $64 per acre conditional payment.
For sugar produced beyond 350 tons, the base rate of payment is reduced.
Using the above assumptions of 40 ton cane, 10 percent recoverable sugar and
the reduced base, Table 2 was made up to help producers estimate their prob-
able conditional payment for an average year.
Molasses payment In addition to the payment a processor makes to the pro-
ducer for each ton of cane delivered to the mill, and in addition to the condi-
tional payment the producer receives from the federal government, the processor
shall pay to the producer for each ton of net sugarcane ground an amount equal
to the product of 5.4 gallons times one-half the excess above 4.75 cents per
gallon of the weighted average net sales price per gallon of blackstrap or
final molasses, f.o.b. mill tanks sold during a previous 12 month period ending
on a specified date.
Table 2. Table for estimating the probable conditional payment
cane and 10 percent recoverable sugar. I
to producers assuming 40 tons per acre
Acreage necessary to Payment Payment Possible conditional
Tons of produce the amount, Base per ton per payment for acreage
sugar assuming 40 tons @ 10% rate, sugar, acre, involved,
produced recoverable $ $ .
0-350 0-87.5 0.80 16.00 64.00 0-5600
350-700 87.5-175 -75 15.00 60.00 5250-10500
700-1000 175-250 .70 14.00 56.00 9800-14000
1000-1500 250-375 .60 12.00 48.00 .12000-18000
1500-3000 375-750 .55 11.00 44.00 16500-33000
3000-6000 750-1500 .525 10.50 42.00 31500-63000
6000-12000 1500-3000 .50 10.00 40.00 60000-120000
12000-30000 3000-7500 .475 9.50 38.00 114000-285000
30000-up 7500-up .30 6.00 24.00 180000-up
1/ Commercially Recoverable Sugar Determination 833.9 for Florida Sugarcane 1962 Crop Table shows that 199.5
pounds of sugar will be recoverable per ton of cane having a sucrose percent in the normal juice of 13.9.
This is approximately the state average for Florida during the past 10 years, and the basis for this pre-
sent table. 199.5 was rounded to 200.0.
Special conditional payment for crop deficiency or abandonment.-
The federal sugar program also gives limited benefits to.growers for crop
losses caused by drought, flood, storm, freeze, diseases or insects. The
disaster must cause damage to all or a substantial part of the crop throughout
the local producing area in which the farm is located.
HARVEST LABOR SYSTEMS
The sugarcane grower can contract for custom harvesting of his crop or he
can assume his own harvest operations.
Custom harvesting -Custom or contract harvesting is similar to familiar con-
tract harvesting of sweet corn. The grower pays a contractor for all harvest
operations in which the contractor provides equipment, labor and harvest necess-
Grower harvesting In this system, the grower provides his own equipment and
labor as well as the normal needs of either domestic or off-shore labor.
Piece work an incentive system whereby laborers are assigned a definite but
reasonable length of row to be harvested for a definite wage. The number of
hours to do the "piece" of work are not specified, but should be less than or
equal to the number of hours that laborers are expected to be present for duty
on the plantation. The assigned length of row is the critical base of this
system. The length must be a movable base for the following reasons:
1. Condition of the cane
a. whether 40-ton cane or 60-ton cane
b. 'whether clean or weedy
c. whether normal or excessively lodged
d. combinations of these factors
2. Weather and working conditions
a. whether hot or cool or cold
b. whether fair or raining
c. combinations of these factors
Experience is necessary to establish the base, along with the power of
observation and an understanding of human nature among ethnic groups. A per-
sonal observation should suffice to show the value of this system of piece
work. Housewives of laborers assigned housing on a certain Louisiana planta-
tion were allowed to increase the family income by doubling as harvesters
during the grinding season. It was observed that they cut a cert in average
length of row working between about 6 a.m. and 5 p.m. When offered piece
work, they accepted and cut the same amount of row by 1 p.m. Then they were
free to do housework or to continue cutting for a bonus payment. The men were
expected to continue cutting, and were paid a bonus for the amount of row cut
from the end of their piece work until 5 p.m.
Task work.- Under this system, an amount of work is assigned, also. The
laborers are expected to finish their task before quitting work for the evening.
However, they are cleared by their supervisor to quit for the day when the task
is accomplished. Under this system, there is no incentive to earn more money,
but rather to finish early to pursue other interests. Experience, again, is
necessary to assure that the "task" is sufficient to keep laborers working
most, but not all the working day. This system allows for idle periods when
rain is falling, since after a shower, a laborer can continue his task until
Day labor.- This is the most inefficient form of labor, draws the poorest
of workers and requires the utmost of supervision. This is the most "social"
of the groups of sugarcane harvesters. A typical group lines itself across a
field, a man every two rows, guaging its speed of movement to the slowest
workers, who exert a drag on the progress through the field. Such a field is
replete (in fact the origin of) with folk singing, tale telling, and reminis-
cing of former days and youthful exploits. Such workers accept the status quo
that they helped to establish, release their strength in amounts so that it will
endure until (or more likely after) the quitting bell rings, are subject to
frequent absenteeism, and cannot be planned upon except on a day-to-day basis.
Some day laborers can be made more efficient by putting them on piece work or
task work, provided they have the initiative and mentality necessary, along
with the ability to generate interest in doing a good job. Another method of
increasing the efficiency of day laborers is to have them work abreast of a
machine that works at a given rate. For instance, scrappers must keep up with
loading operations to prevent being left behind. Any period of idleness during
loading necessitates the worker carrying armfuls of cane extra distances to the
loader, wagons, or the next heap row.
Child labor.- The conditional payment made by the government to growers
has three objectives, the third of which is "to prevent the employment of child
labor in field work". Children under 14 must not be employed. Children be-
tween 14 and 16 must not be employed or permitted to work more than 8 hours
per day. Growers who own 40 percent or more of the crop they are cultivating
are exempted with respect to their own children. Penalty (subtractions from
conditional payment) for failure to observe child labor provisions is $10 per
child per day (or part day) during which a child was employed or permitted to