xt7k3j391j53 https://exploreuk.uky.edu/dips/xt7k3j391j53/data/mets.xml   Kentucky Agricultural Experiment Station. 1962 journals kaes_bulletins_175 English Lexington, Ky. : The Station, 1885- Contact the Special Collections Research Center for information regarding rights and use of this collection. Kentucky Agricultural Experiment Station Bulletin n.175. text Bulletin n.175. 1962 2014 true xt7k3j391j53 section xt7k3j391j53 Regulatory Bulletin 175 Part 1 A
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FEED AND FERTILIZER DEPARTMENT E:
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KENTUCKY AGRICULTURAL EXPERIMENT STATION Va
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Bruce Poundstone, Head of Department M
Robert Mathews, Assistant Administrator & Chief Inspector "\'
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Guy P. Zickefoose, Auditor-Inspector In
W. J. Huffman, Registration Inspector Ax
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FIELD INSPECTORS
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M. M. Davis Neville Hulette Noel J. Howard T;
O. R. Wheeler \V. M. Rcutt
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LABORATORY STAFF
Harry R. Allen J. A. Shrader Lelah Gaull
Valva Midkiff John Ellis Norma Holbrook
J. T. Adair Dewey Newman, Jr. Robert N. Price In
Paul R. Caudill Clyde Bradxvay
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This report compiled and prepared by Bruce Poundstone and W. J. Huffman N,
Analytical data by Laboratory Staff
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Special statistical data explained on pages 15 to 19 by \V. G. Duncan
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 CONTENTS
Page
Explanation of Tables .............,.... . ....... 4
Companies Represented by Samples Reported in This Bulletin ........ 5
Explanation of "Standing of Manufacturers" ..,....,........ 7
Standing of Manufacturers ....... . ........,....... 8
Variation in Fertilizer Analyses . .................... 15
Why A Concern for Variability? ..................,.. 15
Reporting the Analyses of Fertilizer ...,............... 16
Average Analysis. A Measure ...................... 16
Measuring Variability. . .......... . ............. 16
"\Vild" Samples ,... . ...... . ................ 17
Note On Methods of Computation Used ..... . ............ 17
lnformation Given in Tables ....................... 17
Average Percentage of Guarantee and Coefficients of Variation
for all Samples by Fertilizer Manufacturers .....,..... 18
Table 1 - Analyses of Inspection Samples of Mixed Dry Fertilizers . , , . . 20
Table 2 - Analyses of Inspection Samples of Mixed Liquid Fertilizers .... 123
Table 3 - Analyses of Straight Materials . .....,.......... 128
Table 4 - Analyses of Inspection Samples of Rock Phosphate, Soft
Phosphate with Colloidal Clay ,... . ............ 141
Table 5 - Analyses of lnspection Samples of Bone Meal, Dried Manures, etc., 141
nwartl Table 6 — Results of analyses of fertilizer samples in which the
Routt guarantee for Sulfate of Potash was not met ........... 142
Table 7 - Results of analyses of Boron in fertilizers reported in Tables 1 & Z. 145
Table 8 -· Results of analyses of Insecticides in fertilizers shown in Table 1. . 147
  EXPLANATION OF REFERENCES 1N TABLES 1, 2 AND 3
  Information is given for samples where the words "See note" is shown as follows:
Note 1. See Table 6 for analyses of samples in which the guarantee for sulphate of
potash was not met.
Note Z. See Table 7 for the results of analyses of Boron in fertilizers.
Note 3. See Table 8 for the results of analyses of Pesticides in fertilizers.
Note 4. Fertilizer represented by this sample returned to plant and re-worked.
Note 5. Purchaser received a refund based upon this analysis.
1 Note 6. Product re-labeled and sold according to laboratory finding.
Note 7. Purchaser could not be determined; refund based upon the analysis, sent
to charity.
Note 8. Returned to plant.
Note 9. This sample not included in average. Sec "\Vi1d" samples on page 17.
 

 -1 REGULATORY BULLETIN 175
3 This bulletin contains results of analys es of 3, 855 official samples of
commercial fertilizer made during the period January 1 through June 30, 1962.
The average analysis of each plant food element and the coefficient of variation
for each plant food are shown in Tables land Z for each plant. The average per-
, centage of guarantee and the coefficient of variation for all samples of a manu-
` facturer are shown on pages 18 through 19.
l Separate tables are provided for the results of analysis of mixed dry fer-
) tilizer, mixed liquid fertilizer, straight materials, boron, pesticides incorpo-
rated in fertilizer and for the pe rc ent of potash equivalent to excess muriate
‘ where the guarantee for Sulfate of Potash is not met.
EXPLANATION OF TABLES
‘ The information given should be useful to farmers, agricultural workers,
and company representatives in determining how closely a given manufacturer
and plant is meeting the chemical guarantee printed on the bag or tag for all or
specific fertilizers, This may be done by comparing the guarantee shown at the
beginningof each listing of samples with the actual analysis in the column at the
right in terms of nitrogen, available phosphoric acid and potash.
An additional means ofcomparing guarantees with the analyses of samples
is in the percent of relative value found, shown in the extreme right-hand col-
umn. Thc following examples illustrate how this relative value is calculated:
A 5-10-15 sulfate fertilizer is guaranteed to contain 5 units of nitrogen,
10 units of available phosphoric acid and 15 units of potash. Factors for com-
puting the relative values of these plant foods are; 3 for nitrogen, 2 for avail-
able phosphoric acid and 1 for potash. Thus the combined guaranteed value of
the product represented is calculated:
5.0 Units of Nitrogen x 3 : 15. 0
10.0 Units of Available Phosphoric Acid x Z : Z0. O
15.0 Units of Potash x 1 : 15.0
Total computed guaranteed value 50. O
The same procedure is followed for "found values. " Assuming a sample
of 5-10-15 was found to contain 5.1 units of nitr ogen, 10. 2 units of available
phosphoric acid and 15.1 units of potash, the relative found value is computed:
5.1 Units of Nitrogen x 3 : 15. 3
10. 2 Units of Available Phosphoric Acid x Z : 20. -1
15.1 Units of Potash x l : 15.1
Total computed value 50. B
50. B (computed found value of sample) divided by 50.0 (computed guar-
anteed value) tirnes 100 (to arrive at percentage) gives 101. 6 as the percent of
relative value found.
In some samples a deficiency in one nutrient is accompanied by an over-
run in another nutrient, '1`his may be evidence of improper mixing or weighing
by the manufacturer. Extr cme variations of this kind cannot be attributed to
separation of materials (s eg re gation) after the product is bagged though this
may be a minor factor. Excess of one nutrient cannot compensate for deficiency
of another nutrient. The purchaser is entitled to receive the full guarantee for
all nutrients as expressed by the manufacturer's guaranteed analysis.
* The results of analyses of all inspection samples are given in tables 1, Z,
3, -1 and 5. If an analysis shows a deficiency of more than the tolerance, the
amount claimed for nitrogen, phosphoric acid or potash, or if the percent ofthe
relative value is 97 or less, the result is indicated by an asterisk.
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COMMERCIAL FERTILIZER IN KENTUCKY, SPRING SEASON 1963 5
COMPANIES REPRESENTED BY SAMPLES REPORTED IN THIS BULLETIN
Allied Chemical Corp. , Nitrogen Div. Commercial Solvents Corporation
P. O. Drawer 61 260 Madison Avenue
Hopewell, Virginia New York, New York
American Agricultural Chemical Co. Commonwealth Fertilizer Company
100 Church Street Morgantown Road
New York, New York Russellville, Kentucky
American Cyanamid Company, Agr. Div. Cooperative Fertilizer Service
P. O. Box 400 Southern States Building
Princeton, New Jersey Richmond, Virginia
'I`he American Liquid Fertilizer Co. , Inc. Darling and Company
2nd Street and St. Clair 4201 S. Ashland Avenue
Marietta, Ohio Chicago, Illinois
Armour Agricultural Chemical Co. Elanco Products Company
350 Hurt Building Division of Eli Lilly & Company
Atlanta, Georgia 740 Alabama Street
Indianapolis 6, Indiana
Associated Cooperatives, Inc.
750 West 20th Avenue J. H. Erbrich Products Company
Sheffield, Alabama 1120 32nd Street
Indianapolis, Indiana
Bale Fertilizer Company
Horse Cave, Kentucky E"1'own Fertilizer Company
` Cecilia, Kentucky
Bartlett 8; O'Bryan Fertilizer Co.
108 River Road Farmers Fertilizer Company
Owensboro, Kentucky Smiths Grove, Kentucky
Blackstone Guano, Inc. Farmers Supply & Produce Company
Blackstone, Virginia Monticello, Kentucky
Bluegrass Plant Foods, Inc. Federal Chemical Company
Cynthiana, Kentucky 646 Starks Building
Louisville, Kentucky
Bunton Seed Company
300-306 E. Jefferson Street Glasgow Fertilizer Company
Louisville, Kentucky Glasgow, Kentucky
Burley Belt Plant Food Works, Inc. W. R. Grace & Co., Davison Chem. Div.
Route #4 101 N. Charles Street
Lexington, Kentucky Baltimore, Maryland
California Chemical Company W. R. Grace & Co., Nitrogen Div.
Lucas 8; Ortho Way P. O. Box 4915
Richmond, California Memphis, Tennessee
; Carlisle County Fertilizer Co. Gro-Green Chemical Company
Bardwell, Kentucky P. O. Box 132
Shelbyville. Kentucky
Cecil Farm Supply
Star Route Hillenmeyer Nurseries
Owensboro, Kentucky Georgetown Pike
_ Lexington, Kentucky
Central Farmers Fertilizer Co.
205 W. Wacker Drive Hutsen Chemical Company
Chicago, Illinois Railroad Avenue
Murray, Kentucky
Chemical Formulators, Inc.
Nitro, West Virginia International Minerals 8; Chem. Corp.
P. O. Box 67 - Lockland Station
Chilean Nitrate Sales Corporation Cincinnati, Ohio
120 Broadway
New York, New York Kentucky Fertilizer Works, Inc.
P. O. Box 595
Coastal Chemical Company Winchester, Kentucky
Yazoo City, Mississippi

 6 REGULATORY BULLETIN 175
I Continued from previous page
Land-O·Nan Warehouse Sohio Chemical Company
. Sturgis, Kentucky P. O. Box 628
Lima, Ohio
_ Lofts Pedigreed Seed Company
l Chimney Rock Road Southern States Clark Co. Coop.
E Bound Brook, New Jersey Winchester, Kentucky
` Mid-South Chemical Company Spencer Chemical Company
1222 Riverside Boulevard 610 N. Dwight Building
Memphis, Tennessee Kansas City, Missouri
‘ Mississippi Chemical Company The Stadler Fertilizer Company
Yazoo, Mississippi 1010 Dennison Avenue
Cleveland, Ohio
Monsanto Chemical Company
800 N. Lindbergh Boulevard Swift and Company
St. Louis, Missouri Agricultural Chemical Division
National Stock Yards, Illinois
North American Fertilizer Company
Preston Street at Bergman Tennessee Chemical Company
Louisville, Kentucky Div. Armour Agricultural Chem. Co.
Nashville, Tennessee
Ohio Valley Fertilizer, Inc.
P. O. Box 799 Tennessee Corporation
Maysville, Kentucky P. O. Box 7 - Lockland Station
Cincinnati, Ohio
Olin Mathieson Chemical Corporation
P. O. Box 991 Tennessee Valley Authority
Little Rock, Arkansas Sheffield, Alabama
Phillips Petroleum Company Tri-State Chemical Corporation
Adams Building P. O. Box 123
Bortlesville, Oklahoma Henderson, Kentucky
Robin Jones Phosphate Company U. S. Pliosphoric Products Division
204-23rd Avenue, North Tennessee Corporation
Nashville, Tennessee Tampa, Florida
F. S. Royster Guano Company Valley Counties of Kentucky Coop.
Price Chemical Division P. O. Box 351
P. O. Drawer 1940 Murray, Kentucky
Norfolk, Virginia
Victor Chemical Company
Sadler Fertilizer Company 155 North Wacker Drive
Union City, Tennessee Chicago 6, Illinois
Satterwhile, Inv. Virginia-Carolina Clivmical Corp.
Box 145 —l01 East Main Street
Paris, lur Agri. Chexniral Co. -1-1 56 H2 51 -1-1 96
-- »\t1anta. Georgia 1 -1 -- 5 5 --
1 11:trt<»x·:. Florida E 2 -- 1 5 -~
87 { C1i<~r<>1tt—t·. .»\la1>;x1nz1 1 i -- B S -.
1 C`inrinnati. Ohio F 5 ni 1% 5 oi
-- 1 Crystz11Ci1y. xlissnnrg 2 .1 ». 2 2 »-
Bn   .1··f1`¤-rs··m·i11t·, lnrliana 13 10 77 1* 15 oi
Nrxslrsillv. ‘[`··n1n·~;5t·t· 10 *9 00 11 10 *,*1
fl) l`¤rnn¤·ss<·<· C1i¤·1niti;Il(`jt1. 1 1 -- 1 1 --
4(i··;i¤n1¤1\-·1)
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 12 REGULATORY BULLETIN 175
Standing of Manufacturers, Based on Samples Equal to Guaranty in All Respects and
Analyses within Tolerance - Spring Season 1962
STRAIGHT MATERIALS
, _`_—"_=:—_?`"?;”`;"`__"‘ ? §E?Tf`i$>57  T;
, sulfate of potash, boron and
1 COMPANY AND PLANT —·—E5@@$’E——————.——l@¥$@i—— —»—— —
T . qual to guaranty 1 Equal to guaranty C
I Total in all res ects Total or within Toleraircg
_ Number Number Percenti Number Numbe_i;_|_  
Associated Cooperatives, Inc. 3 2 -- 3 3 --
. Inte
Bale Fertilizer Company Z 2 -- 3 3 --
Bluegrass Plant Foods. Inc. ld Z 17 I5 8 53
Cynthiana, Kentucky 4 I -- 4 Z --
Danville, Kentucky 8 I 13 ll 6 55 Kon
Burley Belt Plant Food Works Z 2 -- Z Z -- Law
California Chemical Company Z Z -- Z 2 --
Central Farmers Fertilizer Co. I O -- I 0 -- d
Mi
Chilean Nitrate Sales Corp. I 1 -- I I --
Mis
Commercial Solvents Corp. I O -·— I I --
Mon
Commonwealth Fertilizer Co. 5 Z 40 6 6 100 N
Cooperative Fertilizer Service 30 28 93 38 38 100 Or
in
Bristol, Virginia I l -- I I -- _
Louisville, Kentucky ll 10 91 I5 15 100 PIM
Russellville, Kentucky 5 —l B0 5 5 100
Winchester, Kentucky I3 13 100 17 17 100 F· 5
Pric
Darling and Company I 1 -- I I -·
Sohi
E'toxvn Fertilizer Company Z I -- 2 I ·--
Spex
Federal Chemical Company 14 6 43 16 ll 69
Humbolrlt, Tennessee 1 O -- I 0 --
Louisville, Kentucky 13 6 46 15 Il 73 T
Gro-Green Chemical Company 2 Z -- 4 4 --
W. R. Grace 8: Co., Nit. Prod. Div. 8 B 100 8 8 IOO Ten]
W. R. Grace Ri Company
Davison Chemical Division 13 7 54 17 l·l 82
1 Bartow. Florida 2 O -- 2 1 -- T .
Nashville. Tennessee s s 100 6 6 100 “‘
New Albany, Indiana 6 Z 33 9 7 78 Vin
Hutson Chemical Company 7 4 57 10 9 90
(Continued)
1 Y

 COMMERCIAL FERTILIZER IN KENTUCKY, SPRING SEASON 1962 13
i Standing of Manufacturers, Based on Samples Equal to Guaranty iuA1l Respects and
Analyses within Tolerance - Spring Season 1962
STRAIGHT MATERIALS
Q6?   -2; ::==~ 
n and Analyses of N, PZO5, KZO,
' sulfate of patssh, boron ana
_T_{_ Sam les _ peiigdes
inspaxcu COMPANY AND PLANT Equal to guaranty Equal to guaranty
Jrccrf? Total in all respects Total or wit1iiL'E£ra1ice¤`=¤1=
—·** Number Number Pt-rcent*¥’ Number Number Percenf
-_ International Min. 8; Chem. Corp. 11 ll 100 16 16 100
__ Cincinnati, Ohio 1 l -- 1 1 --
53 Skokie, Illinois 8 8 100 15 13 100
Somerset, Kentucky Z 2 -- Z 2 --
gg Kentucky Fertilizer Works 3 2 -— 5 —l --
__ Land-O·1\!an Warehouse Z Z -- 2 2 --
__ Morganfield, Kentucky 1 l -- 1 1 -—
Sturgis, Kentucky 1 1 —- 1 1 --
-- Mid-South Chemical Company 11 11 100 11 11 100
_- Mississippi Chemical Corp. 1 1 -- 1 1 100
-_ Monsanto Chemical Company 5 Z -- 5 5 --
100
North American Fertilizer Co, 6 —l 67 6 5 83
100 _
Olin Mathieson Chemical Corp. 1 1 -- 1 1 —-
,,36 Phillips Petroleum campmy 1 1 -- 1 1 --
100
100 F. S. Royster Guano Company
Price Chemical Division 1 O -- 1 1 --
__ Sohio Chemical Company 1 1 -- l 1 --
-_ Spencer Chemical Company 9 9 100 9 9 100
6
9 lclenclerson, Kentucky 6 6 100 6 6 100
__ Kansas City, Missouri 5 5 -- 3 5 --
73 1 _
[`ennessee Chemical Company
__ see; /‘.rmour Au. Chem. Co.
100 Tennessee Corporation 7 ~1 57 7 6 86
Cincinnati, Ohio 3 1 -- 5 2 --
82 New Albany, Indiana 5 2 -- 3 5 --
'1`ampa, Florida 1 1 -- 1 1 --
156 TFi—State C1ieniicalCornpany Z 2 -- L I --
7H
I Vallvy Counties of Ky, coop, is 0 100 S 8 100
90
`
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 14 REGULATORY BULLETIN 175
Standing of Manufacturers, Based on Samples Equal to Guaranty in All Respects and
Analyses within Tolerance - Spring Season 1962
V STRAIGHT MATERIALS
. Analyses of N, P 05. KZO,
I sulfate of potash, Zboron and
( Sam les  esticides
1 COMPANY AND PLANT Equal to guaranty Equal to guaranty
i Total in all res  ects Total or within Tolerang
Number Number Percent* Number Number Per<;ent*¥‘
Virginia-Carolina Chemical Corp. B 5 63 8 6 75
Cincinnati, Ohio 3 3 -- 3 3 --
Hopkinsville, Kentucky 2 I -- 2 1 --
Memphis, Tennessee 1 0 -- I 0 --
Nichols, Florida I O -- I I --
Richmond, Virginia 1 I —- I 1 --
West Ky. Liquid Fertilizer Co. 2 2 -- 2 2 --
TOTAL 3,355 1,867 48 12,118 10,3-14 85
Mixed Dry 3,515 1,636 47 11,566 9,864 84
Mixed Liquid 98 46 47 271 229 85
Straight Materials 2-12 185 76 281 251 89
 
*Percent is not indicated when number of samples is less than 5.
**7*See "'I`olerance Scale" on Page 7.
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COIVIIMIERCIAL FERTILIZER IN KENTUCKY, SPRING SEASON l96Z 15
VARIATION IN FERTILIZER ANALYSES
Variation is a basin; trait in the analysis uf fertilizer. The guarantee as
printed on fertilizer bags cannot be accepted as an exact statement of the chem-
ical contents. Rather, it tells what the manufacturer was aiming for and what
'T the purchaser hopes to buy. This is true 0f all fertilizer. There is always var-
gmé iation around some average analysis.
E ·Many causes contribute tie variabi1itv.~ (Par tic lc size and variability in
rance chemical content of raw materials are an initial cause of variation, Methods of
  assembling, weighing, mixing, delivery intu storage piles. and re-handling, in-
— cluding bagging, present further opportunities for variation. Te some extent
5 they may cancel each other and thus minimize variation. They may progres-
sively accumulate and thus magnify variation.
_ The degree of variability in the final fertilizer product is in direct ratio
— tu the variation introclun ed from these causes combined with the care exercised.
I Precision comes enly through the use of properly classified ingredients, em-
ployment of methods that are reasonably exact and carefulness at all stages of
_ manufacture.
- \\'h:itha.s been said 0[ manipulation in manufacture is likewise true of talc-
— ing samples, their handling and analysis in the laboratory. This, toe, may cen-
3 tribute to variation. Differences freni this source, like these brought about in
"'_ the manufacturing precess, may tend tu cancel each other er ean accumulate.
. As in manufacturing, care and precision in the manipulation of samples will re-
duce the degree of variability.
7
'l`he variation caused in laboratory handling is norziially mueh less than
l that in manufacture. For the purpose of this report, variations attributable t0
sampling and the laboratory may be disregarded. They are usually slight. Also
E all samples were taken hy the same inspectors and handled in the laboratory in
the same way. If there is "laboratory bias" it will be tu change all results in
the same directions to the same degree.
WHY A CONCERN FOR VARIABILITY?
The iiianufacturer and the faririer alike are interested in this question uf
variability. Producers of fertilizer as well as purehascrs want a product fully
meeting guarantee. Manufaetnrers know that a certain amount of variability is
unavoidable. This is it factor in suggesting "0ver-formulation" in the industry.
The matter of how much ever-formulation is neeessary varies widely from plant
to plant. The aim or obj ce tive of manufacturing is te have full guarantee as
shown on every bag. If there is variability. it should be confined to values above
the guarantee.
From the userls viewpoint, if fertilizer is variable, sonie purchasers will
pet less than they pay for and others will get more. Also, with variability in
composition, different areas in the field will be treated differently correspond-
ing to the degree of varialiility. The user, therefore, is interested in variability
to the extent that he gets what he pays for, and the fertilizer is sufficiently uni-
form te give the best possible agronomie return.
The fertilizer eontrol offieial is likewise interested in this. His lash is to
see that each bag of fertilizer or the average of any two bags or whatever unit
is selected is reasonably similar to other such units ef quantity sold by a given
manufacturer. Fertiliaer laws infer that the average of the whole lot purchased
should be at least equal to the guarantee. Although there are tolerances permit-
l ting soiiie samples to fall s l1 ght l y under guarantee, these tolerances are not
I large.
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 16 REGULATORY BULLETIN l75
REPORTING THE ANALYSES OF FERTILIZER
In the past, regulatory reports of this Station have published results of
thousands of chemical analyses of fertilizer samples. Some system of charac-
  terization is desirable if these are to be meaningful. Several methods have been
used to bring meaning to these data. Marking deficient samples with an asterisk
2 is one of these. Supplementary tables have been presented showing the standing
of manufacturers based on the c riteria of the percentage of samples equal to
guarantee in all respects and the proportion of analyses above tolerance. Two
, additional ways of diagnosing such data are proposed in this report.
AVERAGE ANALYSIS, A MEASURE
. The statement has been made that the average of a given lot of fertilizer
should at least equal the guarantee. If this is correct, an average of the analy-
ses of several samples of surh a lot will show whether or not this is true.
The printed guarantee on each bag is viewed as the "aim" of the manu-
facturer. The average analysis of actual samples of the fertilizer becomes the
means of statistically measuring the manufacturer‘s "true aim. " The average
analysis has been calculated for all ofthe analyses of mixed fertilizers reported
in this bulletin when as many as two samples are shown, These averages, given
in Tables 1 and 2, follow the words "average analysis. "
MEASURING VARLABILITY
"Average analysis" as an expression of the "true aim" of a manufacturer,
says nothing in the dimension of variability. Some measure is needed to ex-
press the range in analyses on either side ofthe average. To further use the
analogy from marksmanship if "average" measures aim at the target and tells
the center of this aim, °another measure is needed to express the "scatter" of
the various shots. Are they close to the center of "true aim" or are they "wide"
of the mark'?
The coefficient of variation is proposed as a means for reducing this to a
statistic that is useful. The method for doing this will be found in textbooks on
statistics and when applied to a guarantee of 5% nitrogen is calculated as fol-
lows:
Sample Number Nitro ven Guarantee Found Sc uared
A 5. U 5. 6 31. 36
B 5, 0 5. 5 30. 25
C 5, O 5. 4 29. 16
D 5.0 5. 7 32. 49
E 5.0 5. 5 30. 25
F` 5.0 5. 8 33. 64
G 5. O 5.0 25, OO
H 5.0 6. O 36. 00
I 5.0 5. 5 30.25
J 5.0 5. 3 29, OQ
55. 3 306. 49
10 Samples, average analysis : 55. 3 : 5. 53
10
Standard deviation : 106,49 - 55. 32 : \ /0. 68 : O. 275
-
-
A
Coefficient of variation : O, 275 x 100 2 ·l. 7 - 5. 0%
5. 55 t
lf in this example there had been less variation or "scatter", the resulting  
percentage would have been smaller. lf there had been more variation, it would y
have heen larger. The coefficient varies directly with the range in values of
analyses.  
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 COMMERCIAL FERTILIZER IN KENTUCKY, SPRING SEASON 1962 17
"WILD" SAMPLES
No matter how much care is exerted in a fertilizer plant, an occasional
"wild" sample may appear. Such samples are caused by unusual circumstances
such as putting the wrong fertilizer in bags labeled for another grade or large
errors in mixing or manipulation in the factory that cannot be said to represent
usual procedure.
Computations that included such samples would only throw the coefficient
of variation as well as the average analysis completely out of line. They are
judged to be so abnormal they have not been included in these statistical deter-
minations, There were only 57 such samples in the mixed fertilizer samples
reported. Such samples are indicated in the table as "See Note 9. " As a basis
for excluding these samples, the following rules were followed;
l. Throw out any samples more than 110% or less than 90% in relative
value except:
a. The sample is within + 10% of the average sample value.
b. The variation of all the s ample values is such that the samples
more than + 10% appear to fit a normal distribution pattern.
Z. Throw out all of a small group of less than (5) samples if variability
is so great that no clear pattern is apparent.
3. Throw out individual samples whose ratio of ingredients differs
strongly from the balance of samples of the grade. These may in-
clude samples:
a. Whose ratio strongly suggests an entirely different grade of fer-
tilizer.
b. Two or more of whose ingredients are higher or lower by 10% or
more ofthe extreme values of the remaining normal samples.
NOTE ON METPIO