• TABLE OF CONTENTS
HIDE
 Front Cover
 Introduction
 Field study methods
 Forage yields and additional production...
 Effect of N on bahiagrass growth...
 Effect of N on bahiagrass...
 Quality of regrowth vs available...
 Fertilization effect on minerals...
 Soil analyses from demonstration...
 References cited
 Site descriptions and location...
 Back Cover














Group Title: Circular - University of Florida Institute of Food and Agricultural Sciences ; 916
Title: Fertilization of established bahiagrass pasture in Florida
CITATION THUMBNAILS PAGE IMAGE ZOOMABLE
Full Citation
STANDARD VIEW MARC VIEW
Permanent Link: http://ufdc.ufl.edu/UF00014493/00001
 Material Information
Title: Fertilization of established bahiagrass pasture in Florida
Series Title: Circular Florida Cooperative Extension Service
Alternate Title: Bahiagrass pasture in Florida, Fertilization of established
Physical Description: 11 p. : ill. ; 23 cm.
Language: English
Publisher: Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida
Place of Publication: Gainesville
Publication Date: 1991
 Subjects
Subject: Pastures -- Florida   ( lcsh )
Fertilizers -- Application   ( lcsh )
Pastures -- Fertilizers   ( lcsh )
Genre: government publication (state, provincial, terriorial, dependent)   ( marcgt )
bibliography   ( marcgt )
non-fiction   ( marcgt )
 Notes
Bibliography: Bibliography : p. 8.
Statement of Responsibility: Sid Sumner ... <et al.>.
General Note: Cover title.
 Record Information
Bibliographic ID: UF00014493
Volume ID: VID00001
Source Institution: University of Florida
Rights Management: All rights reserved by the source institution and holding location.
Resource Identifier: aleph - 001598033
oclc - 23209250
notis - AHM2170
 Related Items
Other version: Alternate version (PALMM)
PALMM Version

Table of Contents
    Front Cover
        Front Cover
    Introduction
        Page 1
    Field study methods
        Page 1
    Forage yields and additional production cost
        Page 2
    Effect of N on bahiagrass growth distribution
        Page 2
    Effect of N on bahiagrass quality
        Page 3
        Page 4
    Quality of regrowth vs available forage
        Page 5
    Fertilization effect on minerals in bahiagrass
        Page 6
    Soil analyses from demonstration sites
        Page 6
        Page 7
    References cited
        Page 8
    Site descriptions and locations
        Page 9
        Page 10
        Page 11
    Back Cover
        Back Cover
Full Text




Circular 916

II


Fertilization of



established bahiagrass pasture



in Florida






Sid Sumner, Wayne Wade, Jim Selph, Jerry Southwell, Vicky Hoge,
Pat Hogue, Ed Jennings, Pat Miller, and Travis Seawright


i-
. ... ...


Florida Cooperative Extension Service
Institute of Food and Agricultural Sciences
University of Florida
John T. Woeste, dean


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Fertilization of established bahiagrass pasture in Florida

Sid Sumner, Wayne Wade, Jim Selph, Jerry Southwell, Vicky Hoge,
Pat Hogue, Ed Jennings, Pat Miller, and Travis Seawright*


Introduction
There are about 2.5 million acres of bahiagrass
pasture used for beef production in Florida. A
major expense of maintaining this resource is its
annual fertilization. Recognizing this expense, and
the importance of good fertilization practices, the
Florida Cattleman's Association recommended in
1985 that the University of Florida, IFAS, reevalu-
ate the fertilization needs of pasture grasses.
A three-year research study conducted at the
Ona Agricultural Research and Education Center
in the early 1960s (McCaleb et al., 1966) showed
that bahiagrass yield was not increased by phos-
phate (P205) fertilization, and a response to potash
(K20) fertilization was not obtained at rates higher
than 24 pounds per acre (lb/A) annually, even with
120 lbs nitrogen (N)/A applied as a split applica-
tion. Based on soil test values reported in the
study, IFAS fertilizer recommendations called for
annual applications of 48 lb of P205 and 96 lb of
K20/A (Jones et al., 1974). Later modifications of
IFAS recommendations indicated that 40 lb P205
and 80 lb K20/A should have been applied annually
(Whitty et al., 1977).
Research at the Beef Research Unit near Gaines-
ville (Blue, 1970) showed that around 70% of the P
applied to a limed Leon fine sand pasture over an
18-year period had remained in the surface soil.
Further study (Rodulfo and Blue, 1970) showed
that bahiagrass responded to added P205 when
grown in the surface horizon of a virgin soil, but did
not respond to P205 when grown in the surface
horizon of soil from previously-fertilized pasture.
Considering evidence that the P205 and K20
requirements of bahiagrass need to be evaluated
under conditions present on commercial ranches
that have been in production for many years, a field
study was conducted with the following objectives:
1) to determine if bahiagrass pasture responds to


P2O, and K20 fertilization when N fertilization is
60 lb/A/yr, a rate commonly used by ranchers
(IFAS, 1986); and 2) to compare the response of
bahiagrass pasture when fertilized according to
IFAS standard recommendations based on soil tests
with the response of bahiagrass fertilized at lower
rates ofN, P205 and K20.

Field study methods
In 1986, one site in each of nine south Florida
counties was selected. Site locations and descrip-
tions are presented in the appendix. Each site was
a bahiagrass pasture on which a cow/calf manage-
ment system had been in effect for more than 10
years. A site in Pasco County was discontinued
after the first year due to severe mole cricket
damage of the bahiagrass pasture.
At each site, five 50 x 100 ft areas were selected
and assigned one of five fertilization treatments.
These were: 1) no fertilizer; 2) 60 lb N/A applied in
March; 3) 60 lb N, 45 lb P205 and 45 lb K20/A
applied in March; 4) 60 lb N/A applied in March
and 60 lb N/A applied again in September; and 5)
60 lb N, 90 lb P205 and 45 lb K20/A applied in
March and 60 lb N and 45 lb K20/A applied in
September. Nitrogen, phosphate, and potash were
applied as ammonium nitrate, superphosphate, and
potassium chloride, respectively. Treatment 5
represented University of Florida, IFAS standard
recommendations (Whitty et al, 1977) for fertilizing
bahiagrass pasture based on test of soil samples from
each site when the demonstration was initiated.
Soil samples were obtained from each treatment
area immediately prior to fertilization in March
and September each year of the demonstration.
Each soil sample consisted of a composite of five 6-
inch deep cores from each treatment area. Soil
samples were analyzed for pH and for Mehlich-I
extractable P, K, calcium (Ca), zinc (Zn), copper
(Cu), magnesium (Mg), and manganese (Mn).


*The authors are county extension staff at Polk, Hillsborough, Desoto, Hardee, Okeechobee, Highlands, Pasco, and Manatee
Counties, respectively, and participants in the South Florida Beef-Forage Program, Cooperative Extension Service, IFAS, University
of Florida. Appreciation is also extended to R. J. Stephenson, G. Kidder, M. F. Cole, J. S. Brenneman, J. E. Rechcigl, and F. M. Pate
for assistance on this project.











Fertilization of established bahiagrass pasture in Florida

Sid Sumner, Wayne Wade, Jim Selph, Jerry Southwell, Vicky Hoge,
Pat Hogue, Ed Jennings, Pat Miller, and Travis Seawright*


Introduction
There are about 2.5 million acres of bahiagrass
pasture used for beef production in Florida. A
major expense of maintaining this resource is its
annual fertilization. Recognizing this expense, and
the importance of good fertilization practices, the
Florida Cattleman's Association recommended in
1985 that the University of Florida, IFAS, reevalu-
ate the fertilization needs of pasture grasses.
A three-year research study conducted at the
Ona Agricultural Research and Education Center
in the early 1960s (McCaleb et al., 1966) showed
that bahiagrass yield was not increased by phos-
phate (P205) fertilization, and a response to potash
(K20) fertilization was not obtained at rates higher
than 24 pounds per acre (lb/A) annually, even with
120 lbs nitrogen (N)/A applied as a split applica-
tion. Based on soil test values reported in the
study, IFAS fertilizer recommendations called for
annual applications of 48 lb of P205 and 96 lb of
K20/A (Jones et al., 1974). Later modifications of
IFAS recommendations indicated that 40 lb P205
and 80 lb K20/A should have been applied annually
(Whitty et al., 1977).
Research at the Beef Research Unit near Gaines-
ville (Blue, 1970) showed that around 70% of the P
applied to a limed Leon fine sand pasture over an
18-year period had remained in the surface soil.
Further study (Rodulfo and Blue, 1970) showed
that bahiagrass responded to added P205 when
grown in the surface horizon of a virgin soil, but did
not respond to P205 when grown in the surface
horizon of soil from previously-fertilized pasture.
Considering evidence that the P205 and K20
requirements of bahiagrass need to be evaluated
under conditions present on commercial ranches
that have been in production for many years, a field
study was conducted with the following objectives:
1) to determine if bahiagrass pasture responds to


P2O, and K20 fertilization when N fertilization is
60 lb/A/yr, a rate commonly used by ranchers
(IFAS, 1986); and 2) to compare the response of
bahiagrass pasture when fertilized according to
IFAS standard recommendations based on soil tests
with the response of bahiagrass fertilized at lower
rates ofN, P205 and K20.

Field study methods
In 1986, one site in each of nine south Florida
counties was selected. Site locations and descrip-
tions are presented in the appendix. Each site was
a bahiagrass pasture on which a cow/calf manage-
ment system had been in effect for more than 10
years. A site in Pasco County was discontinued
after the first year due to severe mole cricket
damage of the bahiagrass pasture.
At each site, five 50 x 100 ft areas were selected
and assigned one of five fertilization treatments.
These were: 1) no fertilizer; 2) 60 lb N/A applied in
March; 3) 60 lb N, 45 lb P205 and 45 lb K20/A
applied in March; 4) 60 lb N/A applied in March
and 60 lb N/A applied again in September; and 5)
60 lb N, 90 lb P205 and 45 lb K20/A applied in
March and 60 lb N and 45 lb K20/A applied in
September. Nitrogen, phosphate, and potash were
applied as ammonium nitrate, superphosphate, and
potassium chloride, respectively. Treatment 5
represented University of Florida, IFAS standard
recommendations (Whitty et al, 1977) for fertilizing
bahiagrass pasture based on test of soil samples from
each site when the demonstration was initiated.
Soil samples were obtained from each treatment
area immediately prior to fertilization in March
and September each year of the demonstration.
Each soil sample consisted of a composite of five 6-
inch deep cores from each treatment area. Soil
samples were analyzed for pH and for Mehlich-I
extractable P, K, calcium (Ca), zinc (Zn), copper
(Cu), magnesium (Mg), and manganese (Mn).


*The authors are county extension staff at Polk, Hillsborough, Desoto, Hardee, Okeechobee, Highlands, Pasco, and Manatee
Counties, respectively, and participants in the South Florida Beef-Forage Program, Cooperative Extension Service, IFAS, University
of Florida. Appreciation is also extended to R. J. Stephenson, G. Kidder, M. F. Cole, J. S. Brenneman, J. E. Rechcigl, and F. M. Pate
for assistance on this project.








Two 4 x 8 ft wire cattle-exclusion cages were
placed on each 50 x 100 ft treatment area in March.
Cages were positioned on an area where the
bahiagrass had been previously staged to a 2-inch
stubble height, if needed, with a plot harvester.
Forage from a 20-sq-ft area inside and outside each
cage was harvested to a 2-inch stubble every 30 to
60 days from April or May through December. On
each harvest date, each cage was moved to a
pasture area harvested outside that cage, thus
cages were moved around the 50 x 100 ft treatment
areas throughout the year.
Total fresh forage harvested inside and outside
each cage was weighed and sampled for analysis.
Dry matter content was determined on samples
dried in a forced-air dryer at 60C. Dry matter
yield was calculated from fresh weight data and dry
matter content. Crude protein content and total
digestible nutrients (TDN) were determined with a
near-infrared analyzer. Forage samples were
ashed at 6000C and acid digested to determine P, K,
Ca, Mg, Zn, Mn, Cu and iron (Fe).
The field study was initiated in March 1987 and
completed in December 1989.

Forage yields and additional production cost
Two important terms are used in this publication
to describe the type of forage harvested during the
study. Regrowth forage is bahiagrass harvested
inside an animal exclusion cage which had grown
from a 2-inch stubble since the last harvest. Avail-
able forage is bahiagrass harvested outside the
cage and is forage actually available to the grazing
animal. Yield data were obtained from regrowth
harvests.
There was a consistent increase in forage yield to
60 lb of N/A applied in March over the no fertilizer
treatment (Table 1, Appendix Table 1A). Over
three years the treatment receiving 60 lb N/A
averaged 1,760 lb more dry matter per acre annu-
ally than the treatment receiving no fertilizer. It
presently costs about $20/A to apply 60 lb of N,
including $4 per acre spreading cost. This expense
appears justifiable, costing about $23 for each ton
of additional dry forage produced (Table 2).
In comparison to 60 lb of N/A only, a positive
response in dry matter yield was obtained when 45
lb of P205 and 45 lb of K20/A were applied in March
along with 60 lb of N/A (Table 1). However, the
increased production was only 400 lb of dry forage
per acre annually. It costs about $14/A for the P2,O
and K20 and approximately $72 for each additional
ton of dry forage produced.


Applying 60 lb of N/A in March and then again
in September produced an average of 480 lb more
dry matter per acre than one 60 lb N application in
March (Table 1). It would cost about $20/A for the
second N application, and the cost for each addi-
tional ton of dry forage would be about $84 (Table
2). Several research studies have shown a linear
response in dry matter yield of bahiagrass to
increasing rates of N fertilization, even when N
was applied as split applications (Blue, 1966; Blue
and Graetz, 1977). However, these studies did not
evaluate a situation in which one half of the N was
applied as a second application as late as Septem-
ber, a practice used on some ranches in Florida
because of heavy summer rains.
In comparison to two applications of 60 lb N/A, a
positive response was obtained in dry matter yield
with the addition of 90 lb of P205 in March, and 90
lb/A of O20 equally split between March and
September, along with 120 lb of N (Table 1). The
increased yield averaged 700 lb more dry forage per
acre annually than the 120 lb of N/A alone. It
presently costs about $29/A for the P205 and K20
applied, thus costing approximately $82 for each
additional ton of dry forage produced.

Effect of N on bahiagrass growth distribution
Increased yield due to the application of N in
March was immediate, and continued throughout
the summer period (Figure 1). Early spring growth
of pasture forage is important because of low forage
availability after the winter months, and demands
by cows which are usually nursing calves and being
rebred. Typical low spring rainfall was experienced
in all three years of this field study, and yet sub-
stantial responses in forage growth and forage
quality to N fertilization were obtained both in
April and in May. This points out the importance
of applying N fertilizer to bahiagrass pasture as
early as February or March.
The response to N application in September was
also immediate but limited only to the September
or October harvests. Forage growth in general was
reduced after October, because of shorter days, so a
response to N fertilization might not be expected.
The results of this field study document the poor
response of bahiagrass to N applied in September,
and suggest that N should be applied to bahiagrass
as a single application in the spring, but if split, the
second application should be well before Septem-
ber. Research data developed previously at
Gainesville (Blue, 1966; Blue and Graetz, 1977)
support this conclusion.








Two 4 x 8 ft wire cattle-exclusion cages were
placed on each 50 x 100 ft treatment area in March.
Cages were positioned on an area where the
bahiagrass had been previously staged to a 2-inch
stubble height, if needed, with a plot harvester.
Forage from a 20-sq-ft area inside and outside each
cage was harvested to a 2-inch stubble every 30 to
60 days from April or May through December. On
each harvest date, each cage was moved to a
pasture area harvested outside that cage, thus
cages were moved around the 50 x 100 ft treatment
areas throughout the year.
Total fresh forage harvested inside and outside
each cage was weighed and sampled for analysis.
Dry matter content was determined on samples
dried in a forced-air dryer at 60C. Dry matter
yield was calculated from fresh weight data and dry
matter content. Crude protein content and total
digestible nutrients (TDN) were determined with a
near-infrared analyzer. Forage samples were
ashed at 6000C and acid digested to determine P, K,
Ca, Mg, Zn, Mn, Cu and iron (Fe).
The field study was initiated in March 1987 and
completed in December 1989.

Forage yields and additional production cost
Two important terms are used in this publication
to describe the type of forage harvested during the
study. Regrowth forage is bahiagrass harvested
inside an animal exclusion cage which had grown
from a 2-inch stubble since the last harvest. Avail-
able forage is bahiagrass harvested outside the
cage and is forage actually available to the grazing
animal. Yield data were obtained from regrowth
harvests.
There was a consistent increase in forage yield to
60 lb of N/A applied in March over the no fertilizer
treatment (Table 1, Appendix Table 1A). Over
three years the treatment receiving 60 lb N/A
averaged 1,760 lb more dry matter per acre annu-
ally than the treatment receiving no fertilizer. It
presently costs about $20/A to apply 60 lb of N,
including $4 per acre spreading cost. This expense
appears justifiable, costing about $23 for each ton
of additional dry forage produced (Table 2).
In comparison to 60 lb of N/A only, a positive
response in dry matter yield was obtained when 45
lb of P205 and 45 lb of K20/A were applied in March
along with 60 lb of N/A (Table 1). However, the
increased production was only 400 lb of dry forage
per acre annually. It costs about $14/A for the P2,O
and K20 and approximately $72 for each additional
ton of dry forage produced.


Applying 60 lb of N/A in March and then again
in September produced an average of 480 lb more
dry matter per acre than one 60 lb N application in
March (Table 1). It would cost about $20/A for the
second N application, and the cost for each addi-
tional ton of dry forage would be about $84 (Table
2). Several research studies have shown a linear
response in dry matter yield of bahiagrass to
increasing rates of N fertilization, even when N
was applied as split applications (Blue, 1966; Blue
and Graetz, 1977). However, these studies did not
evaluate a situation in which one half of the N was
applied as a second application as late as Septem-
ber, a practice used on some ranches in Florida
because of heavy summer rains.
In comparison to two applications of 60 lb N/A, a
positive response was obtained in dry matter yield
with the addition of 90 lb of P205 in March, and 90
lb/A of O20 equally split between March and
September, along with 120 lb of N (Table 1). The
increased yield averaged 700 lb more dry forage per
acre annually than the 120 lb of N/A alone. It
presently costs about $29/A for the P205 and K20
applied, thus costing approximately $82 for each
additional ton of dry forage produced.

Effect of N on bahiagrass growth distribution
Increased yield due to the application of N in
March was immediate, and continued throughout
the summer period (Figure 1). Early spring growth
of pasture forage is important because of low forage
availability after the winter months, and demands
by cows which are usually nursing calves and being
rebred. Typical low spring rainfall was experienced
in all three years of this field study, and yet sub-
stantial responses in forage growth and forage
quality to N fertilization were obtained both in
April and in May. This points out the importance
of applying N fertilizer to bahiagrass pasture as
early as February or March.
The response to N application in September was
also immediate but limited only to the September
or October harvests. Forage growth in general was
reduced after October, because of shorter days, so a
response to N fertilization might not be expected.
The results of this field study document the poor
response of bahiagrass to N applied in September,
and suggest that N should be applied to bahiagrass
as a single application in the spring, but if split, the
second application should be well before Septem-
ber. Research data developed previously at
Gainesville (Blue, 1966; Blue and Graetz, 1977)
support this conclusion.









Effect of N on bahiagrass quality

When averaged across all harvests in a season,
crude protein content of bahiagrass regrowth forage
increased with increasing rates of N fertilization
(Table 1), but increases were relatively small.
Crude protein increases were most pronounced


20001


1500


1000


500


1987


Forage DM Yield, Ibs/A


Apr May Jun Jul Aug Sep Oct Nov Dec

S No Fert. M 60 Ib N, March = 120 Ib N March/Sept


1988


Apr May Jun Jul Aug Sep Oct Nov Dec

I No Fert, E 60 Ib N, March = 120 Ib N, March/Sept


1989


immediately following N application in March and
September and rapidly diminished within 4 to 8
weeks (Figure 2). Short-term increases in crude
protein content of the magnitude observed would be
important in spring grass when cows grazing this
forage are usually nursing young calves and being
rebred.


1987


% Crude Protein


JUN JUL AUG SEP OCT NOV DEC


S No Fert E 60 Ib N, March E 120 Ib N, March/Sept



, f..m, D.^+.,m 1988


MAY JUN JUL AUG SEP OCT NOV DEC

S No Fert M 60 Ib N, March ED 120 Ib N, March/Sept




% Crude Protein 1989


Apr May Jun Jul Aug Sep Oct Nov Dec

SNo Fert. E 60 Ib N, March E 120 Ib N, March/Sept

Figure 1. Effect of N fertilization on dry matter yield of bahia-
grass by month averaged over eight ranches in
south Florida.


2

MAY JUN JUL AUG SEP OCT NOV DEC

I No Fert M 60 Ib N, March l 120 Ib N, March/Sept

Figure 2. Effect of N fertilization on the crude protein content
of bahiagrass by month averaged over eight ranches
in south Florida.


3









Table 1. Effect of fertilization treatment on annual yield and quality of regrowth bahiagrass harvested from April to December from
nine commercial ranch sites in south Florida.
Na NPKc
March, March,
No Na NPKb Na NKd
Item fert. March March Sept. Sept.

Annual yield, t/A

1987 3.32' 4.06i 4.091 4.36i 4.51'
1988 3.97' 5.06j 5.32' 5.111k 5.72k
1989 4.60' 5.47i 5.82jk 5.91jk 6.30k

Avg. 3.73 4.58 4.78 4.82 5.18

Crude protein. %h

1987e 9.8 10.3 10.4 11.0 10.8
1988' 8.9 9.0 9.4 10.0 10.4
19899 10.5 10.3 10.7 11.2 11.4

Avg. 9.8 10.0 10.2 10.8 10.9

TDN, %

1987 54.0 54.2 54.6 54.7 54.6
1988 52.5 52.7 53.0 53.2 53.6
1989 53.6 54.2 53.9 54.3 54.5

Avg. 53.4 53.8 54.0 54.2 54.3
aN at 60 Ib/A.
bN at 60 Ib/A, PO, at 45 Ib/A, K20 at 45 Ib/A.
cN at 60 Ib/A, P20s at 90 Ib/A, K20 at 45 Ib/A.
dN at 60 Ib/A, K,0 at 45 Ib/A.
eEach 1987 value is an average of 144 samples taken from 9 sites over 8 harvests.
'Each 1988 value is an average of 96 samples taken from 8 sites over 6 harvests.
sEach 1989 value is an average of 112 samples taken from 8 sites over 7 harvests.
hValues are expressed as a % of the dry matter.
'ikAnnual yield means in a line which are followed by a different superscript differ at the .05 probability as determined by Duncan's Multiple
Range. Mean square for error was .38, .51, and .48 ton/A in 1987, 1988, and 1989, respectively.



Table 2. Benefits and cost of bahiagrass fertilization treatments.
Increased cost Cost of each
Fertilization Increased of fertilizer additional ton
treatment yield of to produce of dry forage
comparisons dry forage forageb produced
Ib/acre Ib/acre $/acre $/ton

60 Ib N in March
vs. no fertilizer 1760 20 23

60 Ib N in March plus
60 Ib N in September
vs. 60 Ib N in March 480 20 84

60 Ib N, 45 Ib P2s,
45 Ib K20 in March
vs. 60 Ib N in March 400 14 72

60 Ib N, 90 Ib P20s
45 Ib KO in March
plus 60 Ib N, 45 Ib
K20 in September
vs 60 Ib N in March plus
60 Ib N in September 700 29 82
aBased on three-year forage yield averages.
bN, P205 and KO are charged at 0.27, 0.17 and 0.15 $ per Ib, respectively. Spreading cost was $4/A and charged only to N application since
P2Os and K20 were applied in addition to N.
cCost per ton of additional forage ($) = increased cost per acre for additional fertilizer ($)/(increased yield of dry forage (lb)/2000).









Nitrogen fertilization also increased TDN of
bahiagrass, but increases, when averaged over the
entire year, were relatively small (Table 1). In-
creases in TDN were most evident immediately
following N application (Figure 3). Fertilization
with P and K had little effect on crude protein
content and TDN of bahiagrass.
TnM 1987


JUL AUG SEP OCT NOV DEC


S No Fert M 60 Ib N, March W 120 Ib N, March/Sept


1988


MAY JUN JUL AUG SEP OCT NOV DEC

S No Fert M 60 Ib N, March = 120 Ib N, March/Sept


1989


Quality of regrowth vs available forage

Forage quality values for available forage
responded to fertilization in a manner similar to
that for regrowth forage (data not shown). How-
ever, available forage was lower in crude protein
content and digestibility than regrowth forage, and
from July through the fall this difference became
progressively larger (Figure 4). The crude protein
and TDN requirements for a brood cow nursing a
calf and having average milking ability are about
10% and 58% of the dry matter, respectively (Na-
tional Research Council, 1984). During the spring,
summer, and early fall, cattle would selectively
graze bahiagrass having quality similar to regrowth
forage which would come close to meeting the
requirements of lactating brood cows for crude
protein and TDN. However, in late fall and winter
when bahiagrass stops growing and forage availabil-
ity becomes limited, the quality of forage eaten by
cattle would be similar to that shown for available
forage harvested in October and December. This
forage would only meet the needs of dry, pregnant

% Crude Protein
16
14
12 -







Apr May Jun Jul Aug Sep Oct Nov Dec


'Regrowth' Forage M "Available" Forage


% TDN


0 1 i 1 in: :\: :' : -
MAY JUN JUL AUG SEP OCT NOV DEC

SNo Fert E 60 Ib N, March Li 120 Ib N, March/Sept
Figure 3. Effect of N fertilization on the TDN content of bahia-
grass by month averaged over eight ranches in
south Florida.


Apr May Jun Jul Aug Sep Oct Nov Dec

Regrowth" Forage "Available" Forage
Figure 4. Crude protein content and TDN in regrowth and
available bahiagrass forage by month averaged
over eight ranches in south Florida (three year
average over all fertilizer treatments).








cows, which are about 8% and 54% of the dry mat-
ter, respectively (National Research Council, 1984).

Fertilization effect on minerals in bahiagrass
Fertilization with P205 and K20 increased P and
K content of bahiagrass regrowth forage, and the
degree of increase was related to the amount of P205
and K2O applied (Table 3, Appendix Table 2A).
Dietary P levels recommended by the National
Research Council (1984) for the types of beef cattle
grazing in Florida range from 0.18% of the dry
matter for dry cows to 0.23% of the dry matter for
lactating cows of average milking ability (most
Florida brood cows), and to 0.29% of the dry matter
for lactating cows with superior milking ability.
Phosphorus levels in regrowth forage were highest
in 1987 (Table 3). Only one site had average P levels
below that recommended for most beef cattle and
that was in treatments not fertilized with P205.
Levels of P in bahiagrass were lowest in 1988, and
average P levels of treatments not receiving P20O at
two sites were slightly below that required by most
lactating cows.
The P content in available forage was lower than
the P content in regrowth forage (Figure 5). The P
level was particularly low in available forage in the
fall and winter. These levels would cause P defi-
ciency in lactating brood cows not supplemented
with P. A deficiency in P could have a negative
effect in rebreeding.


S% Phosphorus


May Jun JUI
S *Regrowth' Fo


Figure 5. Phosphorus conte
bahiagrass forage
ranches in south F
fertilizer treatment


1989




L


for Florida (Cunha et al., 1964) would satisfy the P
needs of cattle, and would be more economical than
fertilizing bahiagrass to provide P nutrition for
cattle.
The National Research Council (1984) recom-
mends a dietary K level for beef cattle of 0.5 to 0.7%
of the dry matter. Bahiagrass K levels were below
this range at several sites in 1988. Other minerals
were present in bahiagrass forage in adequate
amounts as recommended by the National Re-
search Council, with the exception of Cu. The
National Research Council recommends that cattle
diets contain 4 to 10 ppm of Cu. Forage copper
levels were at or below the lower end of this range
in many cases. Possibilities of a Cu deficiency for
cattle grazing Florida pastures has long been
recognized, so the addition of this element to the
mineral supplement is recommended routinely
(Cunha et al., 1964).

Soil analyses from demonstration sites
Soil P values were very low (< 10 ppm) to low (10
to 15 ppm) at seven sites and medium (16 to 30
ppm) at only one site (Table 4). Soil K values were
very low (< 20 ppm) to low (20 to 35 ppm) at five
sites, medium (36 to 60 ppm) at two sites and high
(61 to 125 ppm) at only one site. All soil parameters
were variable among sites and with there being no
obvious relationships between any parameter and
bahiagrass yield. Fertilization treatment also had
no effect on any soil parameters. These data
indicate that soil testing as now commonly used to
manage the fertilization of Florida bahiagrass
pastures is of limited value. This could be because
soil test data and plant response relationships were
developed with annual crops and bahiagrass is a
deep-rooted perennial plant.


Fertilizer recommendations for established
bahiagrass
From data developed in this field study in
Aug Sep Oct Nov Dec conjunction with other data from the literature, the
rage AvailabeForagefollowing recommendations are presented for
rage Available" Forage
fertilizing established bahiagrass pasture in
int in regrowth and available Florida. These recommendations support revised
by month averaged over eight University of Florida, IFAS recommendations
-lorida (one year average over all (Kidder et al., 1990)
). (Kidder et al., 1990).


Although a mineral supplement containing P is
recommended for all grazing cattle in Florida,
mineral supplementation would be more critical if
pastures are not fertilized with P20.5 A mineral
supplement similar to one commonly recommended


1. With the annual application of 60 lb or less N/A
of bahiagrass pasture, do not apply any P205 and
K20 for at least 3 years. The field study is
continuing (1990) and future recommendations
of 60 lb/A of N only may be extended to periods
longer than 3 years.








cows, which are about 8% and 54% of the dry mat-
ter, respectively (National Research Council, 1984).

Fertilization effect on minerals in bahiagrass
Fertilization with P205 and K20 increased P and
K content of bahiagrass regrowth forage, and the
degree of increase was related to the amount of P205
and K2O applied (Table 3, Appendix Table 2A).
Dietary P levels recommended by the National
Research Council (1984) for the types of beef cattle
grazing in Florida range from 0.18% of the dry
matter for dry cows to 0.23% of the dry matter for
lactating cows of average milking ability (most
Florida brood cows), and to 0.29% of the dry matter
for lactating cows with superior milking ability.
Phosphorus levels in regrowth forage were highest
in 1987 (Table 3). Only one site had average P levels
below that recommended for most beef cattle and
that was in treatments not fertilized with P205.
Levels of P in bahiagrass were lowest in 1988, and
average P levels of treatments not receiving P20O at
two sites were slightly below that required by most
lactating cows.
The P content in available forage was lower than
the P content in regrowth forage (Figure 5). The P
level was particularly low in available forage in the
fall and winter. These levels would cause P defi-
ciency in lactating brood cows not supplemented
with P. A deficiency in P could have a negative
effect in rebreeding.


S% Phosphorus


May Jun JUI
S *Regrowth' Fo


Figure 5. Phosphorus conte
bahiagrass forage
ranches in south F
fertilizer treatment


1989




L


for Florida (Cunha et al., 1964) would satisfy the P
needs of cattle, and would be more economical than
fertilizing bahiagrass to provide P nutrition for
cattle.
The National Research Council (1984) recom-
mends a dietary K level for beef cattle of 0.5 to 0.7%
of the dry matter. Bahiagrass K levels were below
this range at several sites in 1988. Other minerals
were present in bahiagrass forage in adequate
amounts as recommended by the National Re-
search Council, with the exception of Cu. The
National Research Council recommends that cattle
diets contain 4 to 10 ppm of Cu. Forage copper
levels were at or below the lower end of this range
in many cases. Possibilities of a Cu deficiency for
cattle grazing Florida pastures has long been
recognized, so the addition of this element to the
mineral supplement is recommended routinely
(Cunha et al., 1964).

Soil analyses from demonstration sites
Soil P values were very low (< 10 ppm) to low (10
to 15 ppm) at seven sites and medium (16 to 30
ppm) at only one site (Table 4). Soil K values were
very low (< 20 ppm) to low (20 to 35 ppm) at five
sites, medium (36 to 60 ppm) at two sites and high
(61 to 125 ppm) at only one site. All soil parameters
were variable among sites and with there being no
obvious relationships between any parameter and
bahiagrass yield. Fertilization treatment also had
no effect on any soil parameters. These data
indicate that soil testing as now commonly used to
manage the fertilization of Florida bahiagrass
pastures is of limited value. This could be because
soil test data and plant response relationships were
developed with annual crops and bahiagrass is a
deep-rooted perennial plant.


Fertilizer recommendations for established
bahiagrass
From data developed in this field study in
Aug Sep Oct Nov Dec conjunction with other data from the literature, the
rage AvailabeForagefollowing recommendations are presented for
rage Available" Forage
fertilizing established bahiagrass pasture in
int in regrowth and available Florida. These recommendations support revised
by month averaged over eight University of Florida, IFAS recommendations
-lorida (one year average over all (Kidder et al., 1990)
). (Kidder et al., 1990).


Although a mineral supplement containing P is
recommended for all grazing cattle in Florida,
mineral supplementation would be more critical if
pastures are not fertilized with P20.5 A mineral
supplement similar to one commonly recommended


1. With the annual application of 60 lb or less N/A
of bahiagrass pasture, do not apply any P205 and
K20 for at least 3 years. The field study is
continuing (1990) and future recommendations
of 60 lb/A of N only may be extended to periods
longer than 3 years.









2. For the most efficient use of the fertilizer bud-
get, only after 60 lb of N have been applied to
every bahiagrass acre to be used for grazing
should consideration be given to applying P205
and KIO. At N rates of 100 to 120 lb/A, apply 25
lb/A of P205 and 50 lb/A of K20 if these plant
nutrients test low for the soil. Do not apply P20
and O20 if these nutrients test medium or
higher for the soil.

3. When applying up to 120 lb of N/A, it appears to
be most efficient to apply all of the N as a single
application in the spring. If a split application is


used, the second should be applied before the
first of July.

4. Apply N fertilizer to bahiagrass pasture in Feb-
ruary or March. Bahiagrass produces growth in the
early spring, so a response in both forage growth
and forage quality to N fertilizer will be obtained.
Bahiagrass should continue to benefit into the
growing season from an early N application.

5. A mineral supplement containing P and trace
elements should be available to all cattle grazing
bahiagrass pastures, especially those grazing
pastures not fertilized with P205.


Table 3. Average phosphorus and potassium levels in regrowth bahiagrass receiving different fertilizer treatments at nine commer-
cial ranch sites from April through December of 1987, 1988, and 1989.
Na NPKc
March, March,
No Na NPKb Na NKd
Item Fert. March March Sept. Sept.

Phosphorus. %h

1987e 0.30 0.31 0.34 0.29 0.36
1988' 0.22 0.21 0.27 0.21 0.28
19899 0.27 0.25 0.31 0.24 0.35

Avg. 0.27 0.26 0.31 0.25 0.33

Potassium, %h

1987 0.70 0.79 0.86 0.77 0.93
1988 0.41 0.40 0.45 0.36 0.50
1989 0.88 0.97 1.04 0.84 1.19

Avg. 0.68 0.74 0.81 0.69 0.90
a,b,c,d,e,fg,hSee respective footnotes on table 1.


Table 4. Soil analysis for eight south Florida commercial ranch sites across all fertilization treatments and for fertilization
treatments across all sites.e
Item pH P K Mg Ca Zn Cu Mn

ppm Mehlich-l extractable
County location

Desoto 6.3 11 14 77 372 1.2 0.3 1.0
Hardee 6.1 10 19 51 802 1.2 0.8 1.8
Highlands 5.5 9 70 90 824 1.6 0.4 1.1
Hillsborough 4.7 11 29 44 428 2.4 0.2 1.0
Manatee 4.9 7 36 59 446 2.2 0.2 1.7
Okeechobee 6.1 25 40 48 617 4.2 1.1 3.6
Polk 6.2 3 22 88 678 0.8 0.2 70.7
Sarasota 5.0 6 21 43 474 1.5 0.4 0.4

Fertilization treatment

No fertilizer 5.6 12 35 62 570 1.8 0.4 1.5
N March 5.6 10 28 62 582 1.8 0.5 1.5
NPK Marchb 5.6 10 29 62 587 1.9 0.5 1.3
N March, N Sept.c 5.6 10 29 65 597 2.0 0.4 1.5
NPK March, NK Sept.d 5.6 9 38 63 576 1.9 0.4 1.4
a,b,c,dSee respective footnotes on table 1.
eData obtained from composite of five 6-inch cores from each treatment on each site for three spring and three fall samplings. County values
are the average of 30 samples and treatment values are the average of 120 samples.








References cited
I Blue, W. G. 19_66 "The effect of nitrogen sources,
rates, and application frequencies on Pensacola
bahiagrass forage yields and nitrogen utiliza-
tion." Soil Crop Sci. Soc. Fla. Proc. 26:105-109.
Blue, W. G. 1970. "The effect of lime on retention
of fertilizer phosphorus in Leon fine sand." Soil
Crop Sci. Soc. Fla. Proc. 30:141-150.
Blue, W. G., and D. A. Graetz. 1977. "The effect of
split applications on nitrogen uptake by
Pensacola bahiagrass from an aeric haplaquod."
Soil Sci. Soc. Am. J. 41:927-930.
Cunha, T. J., R. L. Shirley, H. L. Chapman, Jr., C.
B. Ammerman, G. K. Davis, W. G. Kirk, and J.
F. Hentges, Jr. 1964. Minerals for beef cattle in
Florida. Univ. Fla., IFAS, Agri. Expt. Sta. Bull.
683.
Jones, D. W., C. E. Freeman, J. T. Johnson, and E.
B. Whitty. 1974. "Fertilizer recommendations
for agronomic crops in Florida." Soil Crop Sci.
Soc. Fla., Proc. 33:43-45.
IFAS. 1986. Survey of beef-forage practices, south-
central Florida 1986 summary. Pub. PE-9.
Univ. Fla., IFAS, Coop. Ext. Serv., Gainesville.


Kidder, G., E. A. Hanlon, and C. G. Chambliss.
1990. "IFAS standardized fertilization recom-
mendations for agronomic crops." Highlights in
Soil Science, No. 35 (revised), SS-SOS-002.
Univ. Fla., IFAS, Coop. Ext. Serv., Gainesville.
McCaleb, J. E., C. L. Dantzman, and E. M. Hodges.
S 1966. "Response of pangolagrass and pensacola
bahiagrass to different amounts of phosphorus
and potassium." Soil Crop Sci. Soc. Fla. Proc.
26:249-256.
National Research Council. 1984. Nutrient re-
quirements of beef cattle. 6th ed. National
Academy Press, Washington, D.C.
Rodulfo, S., and W. G. Blue. 1970. "The availabil-
ity to forage plants of accumulated phosphorus
in Leon fine sand." Soil Crop Sci. Soc. Fla. Proc.
30:167-174.
Whitty, E. B., D. W. Jones, G. Kidder, C. G.
Chambliss, D. L. Wright, and J. J. Street. 1977.
"Fertilization of field and forage crops." Agron.
Facts No. 70. Univ. Fla., IFAS, Coop. Ext. Serv.,
Gainesville.








Appendix

Site descriptions and locations
Desoto County Carlton 2 x 4 Ranch
Site is located approximately 7 miles south of
Arcadia on State Road 31. It is mapped as Malibar
fine sand on flat high ground. The pasture was
limed and fertilized prior to the study as follows: 2/
26/82 1 ton/acre dolomite; 3/9/82 60 lb N, 30 lb
P20, and 55 lb K0O/acre; 11/22/82 40 lb N, 10 lb
P205 and 20 lb K20/acre. The pasture received no
fertilizer after 11/82. Stocking rate was approxi-
mately 2.6 acres per cow.
Hardee County J. P. Platt Ranch
Site is located approximately 6 miles east of
Zolfo Springs on State Road 66 at the Grass Valley
Ranch. The site is relatively flat and located on a
poorly drained Pomona fine sand soil. Annual
fertilization practices since 1980 have been 70 lb N,
18 lb P205 and 35 lb O20/acre in the spring with 65
lb N applied in the fall. The pasture received 1 ton/
acre of dolomite in 1982. Stocking rate was ap-
proximately 2 acres per cow.
Highlands County Oscar Clemons Ranch
Site is located approximately 5 miles north of
State Road 70 on county road 721. Soil is mapped
as an Immokalee sand. The site is flat and poorly
drained. The pasture was fertilized with 1 ton/acre
of lime every 3 years and 300 lbs/acre of 16-8-8
every other year prior to the study. Stocking rate
was approximately 1 acre per cow.
Hillsborough County Warren Allen Ranch
Site is located east of Brandon near Lithia off
county road 640. The study is located on a flat
poorly drained Ona fine sand. Fertilization prac-
tices were: 4/85 65 lb N/acre; 6/85 60 lb N, 30 lb
P205 and KI0/acre; 3/86 60 lb N, 30 lb P205 and
K20/acre; 7/86 65 lb N, 30 lb P20, and 45 lb KO0/
acre. All fertilizer treatments included a complete
micronutrient mix except in 4/85. Stocking rate
was approximately 2.5 acres per cow.
Manatee County Russell Reagan Ranch
Site is located near Bradenton, approximately 8
miles east of Interstate 75 off of State Road 64 on
Rye Road. It is located on high ground and not


subject to standing water. Soil type is mapped as
an Eau Gallie fine sand. The pasture was estab-
lished over 20 years ago and had not received
fertilizer since 1981 and perhaps earlier. Stocking
rate was approximately 1.5 acres per cow.
Okeechobee County Dirr Farms
Site is located east of Kissimmee River and west
of Okeechobee on State Road 70. The plots are
located on a poorly drained flatwoods Immokalee
fine sand. The pasture was renovated in 1976 and
was fertilized annually from 1974-1984 with 30 lb
N and 25 lb P205 and K2O respectively, plus micro-
nutrients. Fertilizer had not been applied since
1984. The 150 acre pasture was stocked with
approximately 80 dry cows and 4 bulls.
Pasco County Joe Barthle Ranch
Site is located west of Dade City on the west side
of county road 581, 1.3 miles north of county road
578 and 1.2 miles south of Johnston road. The
plots are located on a well-drained Kendrick fine
sand. The site was fertilized in 1984 with poultry
layer waste at the rate of 2 tons/acre. Stocking rate
was approximately 4 acres per cow.
Polk County Jerry Keen Ranch
Site is located approximately 11.5 miles west of
Lake Wales on State Road 60. The site is a poorly
drained flatwoods Myakka fine sand. The pasture
is over 20 years old, was rotovated in the fall of
1985 and overseeded with cool-season annual
grasses. Fertility practices have been as follows:
1980 1 ton dolomite/acre; 1982 50 lb N/acre; 1983
- 40 lb N, 10 lb P205 and 20 lb K20/acre; 1984 90
lb N, 25 lb P205 and K20/acre, plus micronutrients;
1985 120 lb N, 20 lb P205 and 35 lb K20/acre, plus
1 ton dolomite/acre; and 1986 65 lb N/acre. Stock-
ing rate was approximately 2 acres per cow.
Sarasota County Mabry Carlton Ranch
Site is located 21 miles east of Interstate 75 on
State road 72. It is west of Gill Road and approxi-
mately 3 miles west of the Desoto Co./Sarasota Co.
line. The site is on a relatively flat Myakka fine
sand. The pasture had not been fertilized for 10
years prior to 1987. Stocking rate was approxi-
mately 5 acres per cow.









Table 1A. Annual yield and average crude protein and TDN content of regrowth bahiagrass receiving different fertilizer treatments at
nine commercial ranch sites in south Florida from April to December (3-year average).
Na NPKc
March March
County No Na NPKb Na NKd
of site Item Fert. March March Sept. Sept.

Desoto Yield, t/A 2.70 3.76 4.25 4.40 4.33
CP, %e 8.0 8.6 8.9 9.3 9.4
TDN, %e 52.4 52.7 53.2 53.7 53.9

Hardee Yield, t/A 4.33 5.19 5.25 5.40 5.83
CP, % 10.0 10.6 10.6 11.1 11.1
TDN, % 54.1 55.0 54.9 53.1 55.1

Highlands Yield, t/A 3.85 5.89 5.43 5.76 6.24
CP, % 10.8 11.1 10.9 11.6 12.0
TDN, % 54.7 55.2 54.9 55.4 55.5

Hillsborough Yield, tA 3.13 4.28 4.26 4.61 4.99
CP, % 9.2 9.8 9.9 10.8 11.1
TDN, % 53.0 53.7 53.7 53.9 54.3

Manatee Yield, t/A 4.87 5.37 6.26 5.54 5.91
CP, % 11.2 10.9 11.3 11.6 11.8
TDN, % 53.7 52.3 53.8 53.8 54.0

Okeechobee Yield, tA 6.19 6.25 7.36 7.36 7.60
CP, % 10.3 10.7 10.9 11.9 11.8
TDN, % 53.6 53.8 53.7 54.1 54.3

Pascof Yield, tA 1.58 2.09 1.71 2.44 2.85
CP, % 10.0 10.4 9.8 11.0 10.9
TDN, % 53.9 53.9 54.1 54.3 53.7

Polk Yield, t/A 2.72 3.81 3.45 3.25 4.33
CP, % 9.4 9.4 9.8 10.4 10.4
TDN, % 53.0 53.4 52.8 53.7 53.7

Sarasota Yield, t/A 2.90 3.07 3.15 3.28 3.19
CP, % 9.6 8.9 10.0 10.0 10.0
TDN, % 53.1 53.1 53.6 54.0 53.9
aN at 60 lb/A.
bN at 60 Ib/A, POs at 45 Ib/A, K0, at 45 Ib/A.
cN at 60 Ib/A, PP 0at 90 Ib/A, K0, at 45 Ib/A.
dN at 60 Ib/A, K20 at 45 Ib/A.
eValues are averages of 42 samples, and presented as % of dry matter.
'Average of one year.

Table 2A. Average mineral content of regrowth bahiagrass receiving different fertilizer treatments at nine commercial ranch sites in
south Florida from April through December (3-year average).
Nb NPKd
March March
County No Nb NPKc Nb NKe
of site Minerala Fert. March March Sept. Sept.

Desoto P, % 0.24 0.22 0.29 0.25 0.28
K, % 0.41 0.47 0.65 0.53 0.70
Ca, % 0.49 0.54 0.48 0.47 0.46
)Mg, % 0.44 0.43 0.42 0.50 0.40
Zn, ppm 59 58 50 47 44
I Cu, ppm 5 10 5 6 7
{ Mn,ppm 60 40 49 29 38
; Fe, ppm 86 93 89 88 84

Hardee P, % 0.34 0.30 0.34 0.28 0.39
K, % 0.65 0.77 0.83 0.62 0.92
Ca, % 0.49 0.46 0.45 0.50 0.44
Mg, % 0.31 0.36 0.27 0.34 0.27
Zn, ppm 39 41 36 39 39
Cu, ppm 7 6 5 6 5


Mn, ppm 52 55 54 61 66
Fe, ppm 71 75 69 72 72

10










Table 2A cont.
Nb NPKd
March March
County No Nb NPKc Nb NKe
of site Minerala Fert. March March Sept. Sept.


Highlands


Hillsborough








Manatee








Okeechobee










Pasco








Polk


P, %
K, %
Ca, %
Mg, %
Zn, ppm
Cu, ppm
Mn, ppm
Fe, ppm

P, %
K, %
Ca, %
Mg, %
Zn, ppm
Cu, ppm
Mn, ppm
Fe, ppm

P, %
K, %
Ca, %
Mg, %
Zn, ppm
Cu, ppm
Mn, ppm
Fe, ppm

P, %
K, %
Ca, %
Mg, %
Zn, ppm
Cu, ppm
Mn, ppm
Fe, ppm


P, %
K, %
Ca, %
Mg, %
Zn, ppm
Cu, ppm
Mn, ppm
Fe, ppm

P, %
K, %
Ca, %
Mg, %
Zn, ppm
Cu, ppm
Mn, ppm
Fe, ppm


0.25
0.67
0.45
0.24
31
4
25
74

0.32
0.79
0.35
0.36
75
4
93
84

0.29
0.91
0.35
0.28
45
5
104
74

0.32
0.93
0.40
0.23
50
5
61
66


0.27
0.70
0.57
0.28
66
6
72
169

0.17
0.60
0.42
0.35
40
4
21
72


0.33
0.94
0.39
0.24
35
6
52
61

0.31
0.86
0.35
0.34
79
5
87
79

0.25
0.85
0.35
0.28
52
10
88
88

0.31
0.88
0.45
0.26
64
6
70
70


0.28
0.78
0.52
0.28
49
6
68
158

0.18
0.68
0.40
0.35
40
5
22
84


Sarasota P, % 0.21 0.19
K, % 0.48 0.43
Ca, % 0.44 0.38
Mg, % 0.37 0.38
Zn, ppm 66 55
Cu, ppm 6 5
Mn, ppm 69 57
Fe, ppm 74 63
aValues presented on dry matter basis; average of 42 samples taken over 3 years.
bN at 60 Ib/A.
cN at 60 Ib/A, PO25 at 45 Ib/A, K,0 at 45 Ib/A.
dN at 60 Ib/A, P2 at 90 Ib/A, K20 at 45 Ib/A.
eN at 60 Ib/A, K20 at 45 Ib/A.

11


0.32
0.82
0.38
0.23
31
4
41
59

0.37
0.87
0.40
0.37
63
5
90
73

0.32
0.95
0.33
0.28
52
5
102
71

0.35
1.07
0.40
0.23
52
5
58
64


0.29
0.88
0.45
0.30
54
6
78
139

0.24
0.67
0.42
0.37
38
4
23
71

0.28
0.56
0.41
0.36
54
6
63
59


0.30
0.86
0.38
0.24
37
5
51
59

0.30
0.68
0.35
0.49
68
5
90
77

0.26
0.84
0.39
0.36
53
5
93
81

0.31
0.99
0.45
0.27
53
6
67
67


0.27
0.74
0.46
0.30
60
6
79
132

0.16
0.50
0.42
0.45
39
5
23
79

0.20
0.43
0.40
0.44
57
6
65
62


0.40
1.01
0.39
0.22
35
5
71
57

0.38
0.99
0.32
0.34
64
5
88
73

0.33
0.99
0.33
0.28
47
6
96
86

0.34
1.14
0.40
0.23
53
6
78
72


0.30
0.90
0.42
0.25
51
6
87
114

0.27
0.78
0.35
0.41
40
5
28
76

0.28
0.63
0.38
0.32
53
5
59
60





















































































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