Keys to - Philippine Rice Research Institute
Transcript of Keys to - Philippine Rice Research Institute
Iloilo iii
®
SIMPLIFIED SOIL SERIES Keys to
ILOILO
iv Simplified to Key Soil Series
This project was funded by the Knowledge Management and Promotion Program (KMP) and Open Academy for Philippine Agriculture (OpAPA) of PhilRice®.
Philippine Rice Research InstituteCopyright © 2008
Iloilo v
Table of Contents Foreword................................................. vii
The Simplified Key to Soil Series............ 1
Guide to Soil Series Identification........... 2
Soil Color Groups.................................... 5
Black/Dark Brown............................ 6
Strong Brown/Brownish Yellow........ 9
Yellowish Brown/Grayish Yellow....... 12
Soil Profile Pictures................................. 15
Soil Properties that affect crop growth.... 20
Soil Productivity....................................... 23
Crop Suitability Analysis.......................... 25
Soil Management Recommendations..... 31
Soil Taxonomic Classification.................. 41
Appendices:
Steps in Identifying Soil Series................ 49
Soil Sampling................................... 50
Color Determination......................... 51
Texture Determination...................... 52
pH Determination............................. 53
The PalayCheck System......................... 54
References.............................................. 56
vi Simplified to Key Soil Series
Iloilo vii
ForewordThis guidebook on “Simplified Keys to Soil Series Identification” was developed to make the field identification of soils easier.
Soil identification is an important component in rice farming. When the soil is properly analyzed and identified, the risks of incompatible management recommendations will be lessened and selection of knowledge and technologies to apply will be efficient. And that is why we have this Simplified Keys to Soil Series for Iloilo.
This is a good guide for effective nutrient management, which is one of the components of the PalayCheck System, a dynamic rice crop management system that presents easy-to-follow practices to achieve respective Key Checks and improve crop yield and input use efficiency.
It features the different color, texture, pH, coarse fragments, and mottles of the most common soils in Iloilo and contains four simple steps in identifying the soil series right in the field. It also includes the soil productivity index, soil properties that affect crop growth, soil taxonomic classification, crop suitability analysis, and soil management recommendations.
viii Simplified to Key Soil Series
The concept of simplified keys to soil series was first used in Thailand. In the Philippines, the project “Simplification of the Philippine Soil Series for Rice and Corn” started in 2005 under the Nutrient Management Support System (NuMaSS) to provide management recommendations for soils identified in the field.
We thank the farmers, agricultural technologists, and municipal and provincial agricultural officers for helping us validate the soil series, and for their comments and suggestions during the pre-evaluation of this guidebook. We also acknowledge the Bureau of Soils and Water Management (BSWM) for providing the secondary data of the soils.
We hope that this publication can help you identify suitable crops in your area, learn the limitations of your soils for crop production, and subsequently know the corresponding management recommendations.
LEOCADIO S. SEBASTIAN PhilRice Executive Director
Iloilo 1
The Simplified Key to Soil Series
“Simplified Key to Soil Series Identification” is a tool/guide in identifying soil series in the field following simple steps, for the use of researchers, agricultural technologists, extension workers, and other stakeholders of the rice industry, including farmers. Using this guidebook, identification of soils will be more accurate reducing the risks of incompatible management and technology recommendations. Transfer of technology will also be made more easy and efficient.
This guidebook is easy-to-use. It involves only five basic soil properties (color, texture, pH, coarse fragments, and mottles) at 30-50 cm soil depth and four simple steps in identifying the soil series right in the field. Once the soil is identified, suitable crops can be selected, and crop productivity ratings, soil properties that limit production, and soil management recommendations can be determined. Since same soil series behave similarly, the soil management technology in one area can be applied in other areas with the same soil identity.
Ten soil series found in Iloilo (Alimodian, Bantog, Barotac, Faraon, Guimaras, Luisiana, San Rafael, Sara, Sta. Rita, and Umingan) are included in this guidebook.
2 Simplified to Key Soil Series
Guide to Soil Series Identification
1. Choose a vacant area in your field and dig up to 50 cm depth from the surface (see page 50).
2. Get bulk soil sample (500 g) from between 30 cm and 50 cm depth.
3. Compare the soil sample with the color chart in the guidebook (see page 51).
Iloilo 3
4. Take a half handful of the same soil and check its texture by wetting the soil sample (neither too wet, nor too dry) (see page 52).
5. Take one spoonful of the same soil sample and put it in a test tube. Add 7 drops of reagent; shake gently, and compare with pH chart (see page 53).
Lateritic nodules
Manganese concretions Quartz
6. Take note of the presence or absence of coarse fragments such as limestone, rock fragments, lateritic nodules, manganese/Mn (black) and iron/Fe (red) concretions, sand materials, and other observable properties of the soil taken from soil surface up to 50 cm depth.
4 Simplified to Key Soil Series
7. Take note also of other observable soil properties such as polished surface (cutans/slickensides), softness, hardness, stickiness, etc.
8. Use the Simplified Keys to Soil Series Book and compare all soil properties starting from the color until the soil name is identified.
slickensides / polished soil surfaces
Iloilo 5
Black/Dark Brown(go to page 6)
Strong Brown/Brownish Yellow(go to page 9)
Yellowish Brown/Grayish Yellow(go to page 12)
SoilColor Groups
6 Simplified to Key Soil Series
Texture
Clay page 7
Black/Dark Brown
Iloilo 7
Black/Dark Brown
Sta. Rita (Srt)
Coarse Fragments none
pH 7.0-7.5
Others mottles (yellowish brown)
Faraon (Frn)
Coarse Fragments limestone fragments
pH 7.0-7.6
Others none
Texture: Clay
go to page 16
go to page 16
8 Simplified to Key Soil Series
Bantog (Btg)
Coarse Fragments none
pH 7.2-7.6
Othersiron (brownish gray) and manganese (black) mottles
Texture: Clay
go to page 16
Iloilo 9
Texture
Clay page 10
Sandy Clay Loam page 12
Strong Brown/Brownish Yellow
10 Simplified to Key Soil Series
Strong Brown/Brownish Yellow
San Rafael (Srf)
Coarse Fragments faint quartz
pH 4.5-5.8
Others none
Guimaras (Gmr)
Coarse Fragments gravels (black, white, yellow)
pH 6.0-6.8
Others none
Texture: Clay
go to page 17
go to page 17
Iloilo 11
Luisiana (Lsn)
Coarse Fragments none
pH 4.5-5.2
Others mottles (strong brown color)
Texture: Clay
go to page 18
Barotac (Btc)
Coarse Fragments pebbles/red gravels
pH 4.9-6.6
Others manganese and iron concretions/coatings
go to page 18
12 Simplified to Key Soil Series
Sara (Sra)
Coarse Fragments none
pH 6.2-7.0
Othersmottles(dull brown and black spots)
Texture: Sandy Clay Loam
go to page 17
Iloilo 13
Yellowish Brown/Grayish Yellow
Texture
Silt Loam page 14
Clay page 14
14 Simplified to Key Soil Series
Umingan (Umn)
Coarse Fragments gravels and stones
pH 5.8-6.7
Others none
Texture: Silt Loam
go to page 19
Alimodian (Ald)
Coarse Fragments none
pH 5.4-6.9
Others tubulans(greenish gray)
Texture: Clay
go to page 19
Yellowish Brown/Grayish Yellow
Iloilo 15
SoilProfile Pictures
16 Simplified to Key Soil Series
Bantog (Btg)page 21
Faraon (Frn)page 22
Sta Rita (Srt)page 21
Apg
Ag
Bt1
Bt2
Apg
Ag
Bt1
Bt2
00 cm
13
56
116+
Ap
Bwg1
Bwg2
Bwg3
Bwg4
Ap
Bwg1
Bwg2
Bwg3
Bwg4
00 cm
18
24
42
69
117+
A
Bw
BC
A
Bw
BC
00 cm
09
25
35
Iloilo 17
Sara (Sra)page 21
Guimaras (Gmr)page 22
San Rafael (Srf)page 22
Ap1
AP2
Bg1
Bg2
Bg3
BC
Ap1
AP2
Bg1
Bg2
Bg3
BC
00 cm
13
23
38
66
80+
Guimaras (Gmr) p
Ap
AB
Bw1
Bw2
BC1
BC2
Guimaras (Gmr) p Guimaras (Gmr) p
Ap
AB
Bw1
Bw2
BC1
BC2
00 cm
05
33
63
92
122
140+
San Rafael (Srf) p
Ap
AB
Bt1
Bt2
BC
San Rafael (Srf) p San Rafael (Srf) p
Ap
AB
Bt1
Bt2
BC
00 cm
09
23
49
72
100+
18 Simplified to Key Soil Series
Luisiana (Lsn) page 22
Barotac (Btc)page 21
Ap
AB
Bt1
Bt2
Bt3
BC
Ap
AB
Bt1
Bt2
Bt3
BC
Barotac (Btc) p
Ap
BA
Btc1
Btc2
BC1
BC2
Barotac (Btc) p Barotac (Btc) p
Ap
BA
Btc1
Btc2
BC1
BC2
00 cm
20
35
60
89
130+
00 cm
12
27
42
59
90
110+
Iloilo 19
Ap
AB
BW1
BW2
BC
Ap
AB
BW1
BW2
BC
Alimodian (Ald) p23
Ap
AB
Bt1
Bt2
Bt3
BC
Alimodian (Ald) p23Alimodian (Ald) p23
Ap
AB
Bt1
Bt2
Bt3
BC
Umingan (Umn)page 22
Alimodian (Ald)page 21
Ap
AB
BW1
BW2
BC
Ap
AB
BW1
BW2
BC
Alimodian (Ald) p23
Ap
AB
Bt1
Bt2
Bt3
BC
Alimodian (Ald) p23Alimodian (Ald) p23
Ap
AB
Bt1
Bt2
Bt3
BC
00 cm
23
52
91
108+
00 cm
14
55
88
120+
20 Simplified to Key Soil Series
Properties of Different Soil Seriesthat affectthe growthof crops
Iloilo 21
Table 1. Properties of Different Soil Series that Affect the Growth of Crops.
Soil Qualities in Relation to Crop Production
Lowland Soils Upland Soils
Bantog Sara Sta. Rita Alimo-dian Barotac
Soil pH 6.5-7.6 5.5-6.0 6.5-7.2 5.5-6.5 4.9-6.5
N Level medium low low low low
P Level high medium medium medium medium
K Level low medium medium low low
Soil Texture clay, clay loam silty clay clay clay loam
to clay clay
Drainage wellmod-erately well
poor to moder-ately well
mod-erately well
well
Permeabi-lity
slow to very slow
slow to very slow
slow to very slow
moderate-ly slow
moderate to slow
Rock Frag-ments none none none none
rock frag-ments, pebbles and gravels
Effective Soil Depth
deep (150cm)
deep (150cm)
deep (100-150cm)
deep (100-150cm)
moderate-ly deep to deep (60-150cm)
Flooding Hazard
sea-sonal none none none none
Topography flatflat to gently rolling
flatflat to undulat-ing
rolling to steep
Inherent Fertility high moderate
to high high moderate to high
low to moderate
22 Simplified to Key Soil Series
Table 1. (continuation)
Soil Qualities in Relation to Crop Production
Upland Soils
Faraon Guima-ras Luisiana San
RafaelUmi-ngan
Soil pH 7.5-8.0 6.0-7.0 4.5-5.5 4.5-5.0 5.8-6.7
N Level medium low low low low
P Level high medium low medium low
K Level low low low low medium
Soil Texture clay loamy very fine clay
loamy to clayey
silty clay loam
Drainage well well well well well
Perme-ability
very slow to slow
mode-rate moderate mode-
ratemoder-ate
Rock Fragments
lime-stone
rock frag-ments none
rock frag-ments
gravels
Effective Soil Depth
shallow (<50 cm)
deep (100-150 cm)
deep (100-150 cm)
deep (90-120 cm)
deep (150 cm)
Flooding Hazard none none none none sea-
sonal
Topo-graphy
undu-lating, rolling to hilly
rolling to steep
rolling to steep
flat to undulat-ing
gently sloping
Inherent Fertility high moderate low low mode-
rate
Iloilo 23
Soil Qualities in Relation to Crop Production
Upland Soils
Faraon Guima-ras Luisiana San
RafaelUmi-ngan
Soil pH 7.5-8.0 6.0-7.0 4.5-5.5 4.5-5.0 5.8-6.7
N Level medium low low low low
P Level high medium low medium low
K Level low low low low medium
Soil Texture clay loamy very fine clay
loamy to clayey
silty clay loam
Drainage well well well well well
Perme-ability
very slow to slow
mode-rate moderate mode-
ratemoder-ate
Rock Fragments
lime-stone
rock frag-ments none
rock frag-ments
gravels
Effective Soil Depth
shallow (<50 cm)
deep (100-150 cm)
deep (100-150 cm)
deep (90-120 cm)
deep (150 cm)
Flooding Hazard none none none none sea-
sonal
Topo-graphy
undu-lating, rolling to hilly
rolling to steep
rolling to steep
flat to undulat-ing
gently sloping
Inherent Fertility high moderate low low mode-
rate
SoilProductivitySoil productivity is that quality of a soil that summarizes its potential in producing plants or sequences of plants under defined sets of management practices; it is also a synthesis of condition of soil fertility, water control, plant species, soil tilth, pest control and physical environment (Bainroth, 1978: Badayos, 1990). In economic terms, it is a measure of amount of inputs of production factors required to correct soil limitation(s) in order to attain a certain level of production. It is expressed as the average crop yield under defined sets of management classes (Badayos, 1990).
Soil productivity index is used for making comparisons among soils; categorized into inherent and potential. The inherent productivity index is the natural capacity of the soil to produce a given yield; potential refers to the capability of the soil to produce yield after correctible soil constraints had been remedied. In economics, the predicted inherent yield is calculated by multiplying the inherent index by the maximum potential yield of rice; predicted maximum possible yield is computed by multiplying the potential index by the maximum poten-tial yield. For instance, the maximum potential yield in the dry season is 8 tons/hectare, and the inherent and potential productivity ratings for Sara soil is 0.75 and 0.83, respectively. Then, the predicted inherent and potential yields of rice in Sara soils are 6.0 and 6.6 tons/ha, respectively.
24 Simplified to Key Soil Series
Table 2. The soil productivity index for rice.
Soil Series Inherent Productivity
Potential Productivity
Alimodian 0.67 0.80
Bantog 0.72 0.83
Barotac 0.62 0.77
Faraon 0.48 0.60
Guimaras 0.57 0.70
Luisiana 0.23 0.43
San Rafael 0.43 0.55
Sara 0.75 0.83
Sta. Rita 0.65 0.83
Umingan 0.61 0.71
Iloilo 25
CropSuitability Analysis
26 Simplified to Key Soil Series
Soil suitability classification refers to the use of a piece of land on a sustainable basis, based on physical and chemical properties and environmental factors. It is the ultimate aim of soil survey and this may come up through good judgment and a thorough evaluation of soil properties and qualities like depth, texture, slope, drainage, erosion, flooding and fertility. Based from these properties, the suitability of a certain tract of land for crop production is determined.
Suitability ratings denote qualitative analysis of the potential of a certain soil to different crops. It implies what crop(s) would give the highest benefit in terms of productivity and profitability from a given soil type, indicated by S1 as the most suitable, S2 as moderately suitable and S3 as marginally suitable. The symbol N implies that the crop is either currently not suitable (N1) where the effect of limitation is so severe as greatly to reduce the yield and require costly inputs or permanently not suitable (N2) where the limitations cannot be corrected permanently. Crop suitability analysis also provides information on soil properties that limit the production of specified crop(s). The crop suitability analysis for the soils of Iloilo is shown on Table 3.
When using a parametric system, the soil index can be equated into percentage shown below. It means that you can attain 75% of the potential yield of the crop when the soil index is highly suitable (S1) while less than 25% of the potential yield when the soil index is not suitable (N).
S1: soil index >75 S3: soil index 25-50S2: soil index 50-75 N: soil index <25
Crop Suitability Analysis
Iloilo 27
Tabl
e 3.
Th
e cr
op s
uita
bilit
y an
alys
is o
f the
soi
ls o
f Ilo
ilo fo
r di
ffer
ent c
rops
.
Lim
itatio
ns d
ue to
:
t
- to
pogr
aphy
; slo
pe
w
-
drai
nage
; floo
ding
s -
text
ure;
coa
rse
fragm
ents
; soi
l dep
th
f -
soil
ferti
lity
c -
clim
ate
Suita
bilit
y ra
tings
:
S1 -
H
ighl
y su
itabl
e
S2 -
M
oder
atel
y su
itabl
e
S3 -
M
argi
nally
sui
tabl
e
N1
- C
urre
ntly
not
sui
tabl
e
N2
- Pe
rman
ently
not
sui
tabl
e
Soil
Serie
sSl
ope
Ran
geR
ice
Irrig
ated
Lo
wla
ndR
ice
Rai
nfed
Lo
wla
ndR
ice
Rai
nfed
U
plan
dM
aize
Alim
odia
nLe
vel t
o un
dula
ting,
sl
ight
ly ro
lling
to h
illyN
2tS2
tfS2
tfS2
c
Ban
tog
Leve
l to
near
ly le
vel
S1S2
fsS2
fsS2
sc B
arot
acR
ollin
g to
ste
epN
2tS2
tfsS2
tfsS2
tfsc
Far
aon
Und
ulat
ing,
rollin
g &
hilly
N2t
ws
S3tfs
S3tfs
S3tfc
Gui
mar
asR
ollin
g to
hilly
N2t
S3tfs
S3tfs
S2tfc
Lui
sian
aR
ollin
g to
hilly
to s
teep
N2t
fS3
tfsS3
tfN
1tfc
San
Raf
ael
Und
ulat
ing
to ro
lling
N2t
fS2
fwS3
tfsN
1fc
Sar
aLe
vel t
o ge
ntly
rollin
gS2
fS2
fsS2
fwS2
c S
ta. R
itaLe
vel t
o ne
arly
leve
lS2
tfwS3
fsS2
sS2
sc U
min
gan
Leve
l to
undu
latin
gS3
tfws
S3fs
S3fs
S2fs
c
28 Simplified to Key Soil Series
Tabl
e 3.
(c
onti
nuat
ion)
Lim
itatio
ns d
ue to
:
t
- to
pogr
aphy
; slo
pe
w
-
drai
nage
; floo
ding
s -
text
ure;
coa
rse
fragm
ents
; soi
l dep
th
f -
soil
ferti
lity
c -
clim
ate
Suita
bilit
y ra
tings
:
S1 -
H
ighl
y su
itabl
e
S2 -
M
oder
atel
y su
itabl
e
S3 -
M
argi
nally
sui
tabl
e
N1
- C
urre
ntly
not
sui
tabl
e
N2
- Pe
rman
ently
not
sui
tabl
e
Soil
Serie
sSl
ope
Ran
geB
eans
Tom
ato
Toba
cco
Suga
rcan
e
Alim
odia
nLe
vel t
o un
dula
ting,
slig
htly
rollin
g to
hilly
S3fc
S2fs
cS3
scS3
fc
Ban
tog
Leve
l to
near
ly le
vel
S3sc
S3w
scS3
scS3
sc
Bar
otac
Rol
ling
to s
teep
S3tfs
cS3
tfsc
S3tfs
cS3
tfsc
Far
aon
Und
ulat
ing,
rollin
g &
hilly
S3tfs
cN
2tsc
S3tfs
cS3
tfsc
Gui
mar
asR
ollin
g to
hilly
S3tc
S3tfs
cS3
tfcS3
tfc
Lui
sian
aR
ollin
g to
hilly
to s
teep
S3tfc
S3tfc
S3tfs
cS3
tfc
San
Raf
ael
Und
ulat
ing
to ro
lling
N1f
cN
1fc
N1f
cS3
fc
Sar
aLe
vel t
o ge
ntly
rollin
gS3
fwc
S2fw
cS3
fsc
S3fc
Sta
. Rita
Leve
l to
near
ly le
vel
S3sc
N2s
cS3
fsc
S3c
Um
inga
nLe
vel t
o un
dula
ting
S3fs
cN
2fsc
S3fs
cS3
fsc
Iloilo 29
Lim
itatio
ns d
ue to
:
t
- to
pogr
aphy
; slo
pe
w
-
drai
nage
; floo
ding
s -
text
ure;
coa
rse
fragm
ents
; soi
l dep
th
f -
soil
ferti
lity
c -
clim
ate
Suita
bilit
y ra
tings
:
S1 -
H
ighl
y su
itabl
e
S2 -
M
oder
atel
y su
itabl
e
S3 -
M
argi
nally
sui
tabl
e
N1
- C
urre
ntly
not
sui
tabl
e
N2
- Pe
rman
ently
not
sui
tabl
e
Soil
Serie
sSl
ope
Ran
geSw
eet
Pota
toC
assa
vaO
nion
Wat
erm
elon
Alim
odia
nLe
vel t
o un
dula
ting,
slig
htly
rollin
g to
hilly
S3fc
S2w
sN
2fsc
S2fs
Ban
tog
Leve
l to
near
ly le
vel
S3fs
cS3
ws
N2s
cS3
s
Bar
otac
Rol
ling
to s
teep
S3tfs
cS3
tfsN
2tfs
cS3
tfs
Far
aon
Und
ulat
ing,
rollin
g &
hilly
S3tfs
cN
2tfs
N2t
fsc
N2t
fs
Gui
mar
asR
ollin
g to
hilly
S3tfc
S2tf
N2t
fcS3
tf
Lui
sian
aR
ollin
g to
hilly
to s
teep
N1t
fcS2
tfN
2tfc
S3tfs
San
Raf
ael
Und
ulat
ing
to ro
lling
S3fc
S3f
N2f
cN
1f
Sar
aLe
vel t
o ge
ntly
rollin
gS3
fwc
S2fw
N2f
wc
S2fw
s
Sta
. Rita
Leve
l to
near
ly le
vel
S3fs
cS3
ws
S3sc
S3s
Um
inga
nLe
vel t
o un
dula
ting
S3sc
S2fs
S3fs
cS3
fs
30 Simplified to Key Soil Series
Soil
Serie
sSl
ope
Ran
geB
anan
aPa
paya
Man
goC
ocon
ut
Alim
odia
nLe
vel t
o un
dula
ting,
slig
htly
ro
lling
to h
illyS2
fS2
fws
S2fs
S1
Ban
tog
Leve
l to
near
ly le
vel
S2fs
N2w
sS3
ws
S3s
Bar
otac
Rol
ling
to s
teep
S2tfs
S2tfs
S3tfs
S2tfs
Far
aon
Und
ulat
ing,
rollin
g &
hilly
S3tfs
S3tfs
N2t
fsS3
fs
Gui
mar
asR
ollin
g to
hilly
S3tf
S3tf
S3tf
S2tf
Lui
sian
aR
ollin
g to
hilly
to s
teep
S3tf
S3tfs
S3tfs
N1t
f
San
Raf
ael
Und
ulat
ing
to ro
lling
S2fs
N2f
S3f
S3f
Sar
aLe
vel t
o ge
ntly
rollin
gS2
fwS3
fws
S3fw
S2w
s
Sta
. Rita
Leve
l to
near
ly le
vel
S2fs
S3fw
sS3
ws
S3w
Um
inga
nLe
vel t
o un
dula
ting
S3fs
S3fs
S3fs
S2fs
Tabl
e 3.
(c
onti
nuat
ion)
Lim
itatio
ns d
ue to
:
t
- to
pogr
aphy
; slo
pe
w
-
drai
nage
; floo
ding
s -
text
ure;
coa
rse
fragm
ents
; soi
l dep
th
f -
soil
ferti
lity
c -
clim
ate
Suita
bilit
y ra
tings
:
S1 -
H
ighl
y su
itabl
e
S2 -
M
oder
atel
y su
itabl
e
S3 -
M
argi
nally
sui
tabl
e
N1
- C
urre
ntly
not
sui
tabl
e
N2
- Pe
rman
ently
not
sui
tabl
e
Iloilo 31
Soil ManagementRecommendations
32 Simplified to Key Soil Series
The goal of soil management is to protect the soil and enhance its performance to increase farm profitably and preserve environmental quality. It is the combination of soil factors to maximize crop production at the lowest possible cost while leaving the soil in a productive state. It involves: maintaining the soil in good physical condition and its soil fertility status, and influencing the biological aspect of the soil so that maximum benefits result (Harpstead, et.al. 1997). Soil management recommendations suitable for each soil identified are enumerated in the succeeding pages (Table 4). In coming up with soil management recommendations, soil properties such as texture, mineralogy, moisture and temperature regimes, and climate were considered since these factors affect crop growth. These properties cannot be changed but controlled tillage, crop rotation, soil amendments, and other management choices can be done. Through these choices, the structure, biological activity, and chemical content of soils can be altered to influence erosion rates, pest population, nutrient availability, and crop production.
Soil Management Recommendations
Iloilo 33
Tabl
e 4.
Th
e so
il se
ries
of I
loilo
wit
h th
eir
limit
atio
ns fo
r cr
op p
rodu
ctio
n an
d co
rres
pond
ing
man
agem
ent r
ecom
men
dati
ons
for
diff
eren
t cro
ps.
Soil
Serie
s Li
mita
tions
for c
rop
prod
uctio
n
Soil
Man
agem
ent R
ecom
men
datio
ns
Ric
eD
iver
sifie
d cr
ops
Roo
t cro
pTr
ee/F
ores
t/Pl
anta
tion
crop
Alim
odia
nhe
avy
clay
su
bsoi
l tha
t can
im
pede
inte
rnal
dr
aina
ge
and
root
de
velo
pmen
t; to
pogr
aphy
; lo
w fe
rtilit
y
ferti
lizat
ion;
see
d be
d co
nfigu
ratio
n;
terra
cing
orga
nic
mat
ter
inco
rpor
atio
n;
limin
g; m
inim
um
tilla
ge; d
eep
plow
ing;
m
ulch
ing;
sui
ted
to c
orn
deep
plo
win
g;
appl
icat
ion
of
ferti
lizer
plan
t cov
er
crop
s, tr
ees
and
legu
mes
to
rest
ore
ferti
lity
and
min
imiz
e er
osio
n; p
ut u
p di
kes
of s
tone
s ac
ross
the
slop
e
Cro
ppin
g Pa
ttern
: ric
e-m
aize
/sor
ghum
/veg
etab
les/
root
cro
ps
34 Simplified to Key Soil Series
Soil
Serie
s Li
mita
tions
for c
rop
prod
uctio
n
Soil
Man
agem
ent R
ecom
men
datio
ns
Ric
eD
iver
sifie
d cr
ops
Roo
t cro
pTr
ee/F
ores
t/Pl
anta
tion
crop
Bant
ogpo
or d
rain
age;
hig
h sh
rink
and
swel
l ca
paci
ty u
pon
wet
ting
and
dryi
ng p
rodu
cing
w
ide
crac
ks in
the
soil,
har
d w
hen
dry;
se
ason
al fl
oodi
ng
in lo
w a
reas
; slo
w
perm
eabi
lity;
irrig
atio
n w
ater
prac
tice
shal
low
cu
ltiva
tion
whe
n so
il m
oist
ure
is a
t opt
imum
; su
ited
for
irrig
ated
and
ra
infe
d pa
ddy
rice;
mai
ntai
n pr
oper
ly th
e pa
ddy
dike
s
cons
truct
ion
of
adeq
uate
dra
inag
e irr
igat
ion
and
flood
co
ntro
l sys
tem
due
to
sea
sona
l floo
ding
ha
zard
in lo
w a
reas
; us
e of
bro
adbe
ds,
ridge
s or
furro
ws
and
mul
chin
g;
appl
icat
ion
of
orga
nic
mat
ter a
nd
farm
man
ure
esta
blis
hmen
t of
ade
quat
e dr
aina
ge a
nd
irrig
atio
n sy
stem
; ap
plic
atio
n of
or
gani
c m
atte
r an
d fa
rm m
anur
e
unsu
itabl
e un
der p
rese
nt
cond
ition
but
be
com
e su
it-ab
le if
pro
per
man
agem
ent
prac
tices
like
es
tabl
ishm
ent o
f ad
equa
te d
rain
-ag
e an
d flo
od
cont
rol s
yste
ms;
us
e of
sui
tabl
e tre
e sp
ecie
s an
d pr
oper
fe
rtiliz
atio
n
Cro
ppin
g Pa
ttern
: ric
e-ric
e; ri
ce-d
iver
sifie
d cr
ops/
vege
tabl
es/ro
ot c
rops
;
rice-
mun
go/to
bacc
o/co
rn
Tabl
e 4.
(c
onti
nuat
ion)
Iloilo 35
Baro
tac
iron
and
alum
inum
to
xici
ty; a
cidi
c; lo
w
ferti
lity
stat
us; d
ifficu
lt to
man
age;
run-
off;
grav
els
are
pres
ent i
n al
l hor
izon
; top
ogra
phy
appl
icat
ion
of p
hosp
hate
fe
rtiliz
ers;
di
kes
cons
truct
ion
limin
g; a
pplic
atio
n of
fres
hly
deco
mpo
sed
orga
nic
mat
ter
not s
uita
ble
for r
oot
crop
s du
e to
gra
vels
plan
t cov
er
crop
s, tr
ees
and
legu
mes
to
rest
ore
ferti
lity
and
min
imiz
e er
osio
n; u
se
of lo
cally
ad
apte
d tre
e va
rietie
sC
ropp
ing
Patte
rn:
upla
nd ri
ce-c
orn;
div
ersi
fied
crop
s-di
vers
ified
cro
ps; t
rees
Fara
onsh
allo
w s
oil d
epth
lim
iting
pro
duct
ivity
to
shal
low
root
ed c
rops
; ou
tcro
ps p
rese
nt;
topo
grap
hy
cons
truct
ion
of
bund
sco
ntou
r far
min
g;
shal
low
cul
tivat
ion;
fe
rtiliz
atio
n
not s
uita
ble
for r
oot
crop
s du
e to
out
crop
s pr
esen
t
suite
d fo
r fru
it, fo
rest
an
d ot
her
hard
woo
d tre
es e
.g.
citru
s,
man
go, i
pil,
mol
ave,
co
conu
t etc
.
Cro
ppin
g Pa
ttern
: ric
e-ric
e; ri
ce-d
iver
sifie
d cr
ops/
vege
tabl
es/ro
ot c
rops
36 Simplified to Key Soil Series
Soil
Serie
s Li
mita
tion
for c
rop
prod
uctio
n
Soil
Man
agem
ent R
ecom
men
datio
ns
Ric
eD
iver
sifie
d cr
ops
Roo
t cro
pTr
ee/F
ores
t/Pl
anta
tion
crop
Gui
ma-
ras
topo
grap
hy;
low
CEC
; ru
n-of
f
appl
icat
ion
of fe
rtiliz
ers
to in
crea
se
yiel
d;
cons
truct
ion
of b
unds
; te
rraci
ng
orga
nic
mat
ter i
ncor
pora
tion;
pr
actic
e co
ver c
ropp
ing,
gre
en
man
urin
g an
d lim
ing;
pla
nt w
ith
legu
mes
to lo
w n
utrie
nt le
vels
; te
rraci
ng
suite
d fo
r ca
mot
esu
ited
for
coco
nut a
nd
fruit
trees
; pla
nt
loca
lly a
dapt
ed
varie
ties;
te
rraci
ng
Cro
ppin
g Pa
ttern
: co
conu
t/fru
it tre
es-d
iver
sifie
d cr
ops/
root
cro
ps
up
land
rice
- div
ersi
fied
crop
s/ ro
ot c
rops
Luis
i-an
ahi
ghly
leac
h-ed
; ver
y ac
id-
ic; i
ron
and
alum
inum
to
xici
ty; l
ow
base
sat
ura-
tion
and
low
C
EC; r
un-o
ff;
topo
grap
hy
limin
g;
ferti
lizer
ap
plic
atio
n;
best
sui
ted
for r
ice
prac
tice
cont
our f
arm
ing,
stri
p cr
oppi
ng a
nd c
over
cro
ppin
g;
appl
icat
ion
of fe
rtiliz
er
suite
d fo
r roo
t cr
ops
suite
d fo
r pe
rman
ent
crop
s an
d tre
es
to re
stor
e th
e fe
rtilit
y of
the
soil
Cro
ppin
g Pa
ttern
: up
land
rice
-div
ersi
fied
crop
s/ro
ot c
rops
; fru
it tre
es/fo
rest
tree
s
Tabl
e 4.
(c
onti
nuat
ion)
Iloilo 37
Soil
Serie
s Li
mita
tion
for c
rop
prod
uctio
n
Soil
Man
agem
ent R
ecom
men
datio
ns
Ric
eD
iver
sifie
d cr
ops
Roo
t cro
pTr
ee/F
ores
t/Pl
anta
tion
crop
Gui
ma-
ras
topo
grap
hy;
low
CEC
; ru
n-of
f
appl
icat
ion
of fe
rtiliz
ers
to in
crea
se
yiel
d;
cons
truct
ion
of b
unds
; te
rraci
ng
orga
nic
mat
ter i
ncor
pora
tion;
pr
actic
e co
ver c
ropp
ing,
gre
en
man
urin
g an
d lim
ing;
pla
nt w
ith
legu
mes
to lo
w n
utrie
nt le
vels
; te
rraci
ng
suite
d fo
r ca
mot
esu
ited
for
coco
nut a
nd
fruit
trees
; pla
nt
loca
lly a
dapt
ed
varie
ties;
te
rraci
ng
Cro
ppin
g Pa
ttern
: co
conu
t/fru
it tre
es-d
iver
sifie
d cr
ops/
root
cro
ps
up
land
rice
- div
ersi
fied
crop
s/ ro
ot c
rops
Luis
i-an
ahi
ghly
leac
h-ed
; ver
y ac
id-
ic; i
ron
and
alum
inum
to
xici
ty; l
ow
base
sat
ura-
tion
and
low
C
EC; r
un-o
ff;
topo
grap
hy
limin
g;
ferti
lizer
ap
plic
atio
n;
best
sui
ted
for r
ice
prac
tice
cont
our f
arm
ing,
stri
p cr
oppi
ng a
nd c
over
cro
ppin
g;
appl
icat
ion
of fe
rtiliz
er
suite
d fo
r roo
t cr
ops
suite
d fo
r pe
rman
ent
crop
s an
d tre
es
to re
stor
e th
e fe
rtilit
y of
the
soil
Cro
ppin
g Pa
ttern
: up
land
rice
-div
ersi
fied
crop
s/ro
ot c
rops
; fru
it tre
es/fo
rest
tree
s
San
Raf
ael
iron
and
alum
inum
to
xici
ty;
acid
ic; v
ery
low
nat
ive
ferti
lity;
ru
n-of
f; to
pogr
aphy
appl
icat
ion
of fe
rtiliz
er;
cons
truct
ion
of b
unds
limin
g; fe
rtiliz
atio
n; o
rgan
ic
mat
ter i
ncor
pora
tion;
mul
chin
g;
inte
rcro
ppin
g; m
ultip
le
crop
ping
; ter
raci
ng
suite
d fo
r roo
t cr
ops
suita
ble
for
fore
st tr
ees;
pl
ant l
ocal
ly
adap
ted
varie
ties
Cro
ppin
g Pa
ttern
: up
land
rice
-root
cro
ps/ d
iver
sifie
d cr
ops;
fore
st tr
ees
Sara
soil
hard
enin
g ca
usin
g su
rface
cr
acki
ng
and
diffi
culty
in
tilla
ge;
acid
ic; l
ack
of ir
rigat
ion
need
s lim
ing;
fe
rtiliz
atio
n of
com
plet
e fe
rtiliz
er;
cons
truct
ion
of ir
rigat
ion
syst
em
limin
g; ti
min
g of
land
pr
epar
atio
n; s
ub-s
oilin
gno
t sui
ted
for r
oot
crop
ssu
itabl
e fo
r tre
es; p
lant
to
acid
tole
rant
cr
ops
e.g.
le-
gum
es, c
ocon
ut
Cro
ppin
g Pa
ttern
: ric
e-ric
e; ri
ce-d
iver
sifie
d cr
ops/
vege
tabl
es/ro
ot c
rops
38 Simplified to Key Soil Series
Soil
Serie
s Li
mita
tion
for c
rop
prod
uctio
n
Soil
Man
agem
ent R
ecom
men
datio
ns
Ric
eD
iver
sifie
d cr
ops
Roo
t cro
pTr
ee/F
ores
t/Pl
anta
tion
crop
Sta.
R
itaso
il ha
rden
ing
caus
ing
surfa
ce
crac
king
and
di
fficu
lty in
tilla
ge
phos
phat
e fe
rtiliz
atio
n;
best
sui
ted
for r
ice
orga
nic
mat
ter
inco
rpor
atio
n; c
over
cro
ps;
mul
chin
g; c
onst
ruct
ion
of b
road
beds
, rid
ges
and
furro
ws;
sui
ted
for
suga
rcan
e
not s
uite
d du
e to
text
ure
cons
train
ts
suita
ble
for t
rees
; pl
ant l
ocal
ly
adap
ted
varie
ties
Cro
ppin
g Pa
ttern
: ric
e-di
vers
ified
cro
ps; c
orn/
suga
rcan
e-co
rn/s
ugar
cane
; ric
e-co
rn/m
ungo
/legu
mes
; coc
onut
s
Tabl
e 4.
(c
onti
nuat
ion)
Iloilo 39
Um
i-ng
anpr
esen
ce o
f gr
avel
ly o
r sto
ny
laye
r at t
he lo
wer
su
bsoi
l. D
ue to
th
is la
yer o
f sto
nes
and
grav
els,
th
e so
ils te
nd
to b
e dr
ough
ty;
occu
rrenc
e of
flo
ods
durin
g an
d af
ter h
eavy
rain
s
appl
icat
ion
of fe
rtiliz
er;
suite
d fo
r pa
ddy
rice
and
othe
r cr
ops;
cl
earin
g of
la
rge
grav
els
and
rock
ou
tcro
ps
cons
truct
ion
of a
dequ
ate
drai
nage
irrig
atio
n an
d flo
od c
ontro
l sys
tem
; ap
plic
atio
n of
ferti
lizer
and
or
gani
c m
atte
r; su
ited
for
dive
rsifi
ed c
rops
; adj
ust t
he
crop
ping
sea
son
grav
els
at th
e lo
wer
sub
soil
may
cau
se th
e lo
wer
yie
ld o
f ro
ot c
rops
clea
ring
of la
rge
grav
els
and
rock
ou
tcro
ps; s
uita
ble
for t
rees
suc
h as
co
conu
t, at
is e
tc
Cro
ppin
g Pa
ttern
:ric
e-di
vers
ified
cro
ps/v
eget
able
s/ro
ot c
rops
; div
ersi
fied
crop
s/ro
ot c
rops
- div
ersi
fied
crop
s/ro
ot c
rops
40 Simplified to Key Soil Series
Iloilo 41
Soil TaxonomicClassification
42 Simplified to Key Soil Series
Soil Taxonomic ClassificationSoil taxonomy is a system of naming, describing, and categorizing soils. It helps us to understand how soils had formed, changed, and their effects on crops and natural resource management. It uses a specific nomenclature that both classifies the soil and gives a distinctive name to the individual soil. Names are constructed from the formative elements (generally originating from Greek and Latin) which are used in specific combinations to provide a highly descriptive name to a specific soil type.
Scientists have developed different systems of soil classification to group soils of similar properties in one class, allowing them to exchange information on soils found in different areas. In the classification scheme, characteristics and information about the soil become more specific as one continues from order, sub-order, great group, sub-group, family, to series level. For this purpose, the USDA Soil Taxonomic Classification scheme was employed for technical use of researchers and students. Soil Taxonomic Classification that implies the general features of a given soil indicating its texture, mineralogy, moisture and temperature regimes, diagnostic horizons, and soil order is presented in Table 5 (pages 43-47). These features/properties influence crop growth and serve as basis for transferability of soil management technology.
Iloilo 43
Soil Series
Taxonomic Classification
Interpretation
Ali-modian
Fine, smectitic (ca.), isohyperthermic, CALCIC HAPLUSTALFS
This is a fine-textured soil with large amount of clay (35-60%) and isohyperthermic temperature regime (>22°C). It is an Alfisol (alf), i.e. there is illuvial accumulation of clay in the subsoil horizons from the underlying horizons. It has minimum complexity in its soil horizonation (hapl-) found in areas with pronounced wet and dry seasons (-ust). It is a member of the great group Haplustalfs with high percentage of calcium saturation in the subsoil (calcic).
Bantog Very fine, mixed, isohyperthermic, AERIC CALCIAQUERT
This is a very fine-textured soil with high clay content of >60% and has isohyperthermic temperature regime (>22°C). It is a Vertisol(-ert), dominated by shrink-swell clays that cause deep wide cracks, slickensides, very sticky when wet and compact when dry. It is saturated with water repeatedly (aqu-) but not as wet as the typical, i.e. it is better aerated, usually because either groundwater is deep or the period of saturation is shorter (aeric). This soil also has high calcium saturation (calci-) in its subsoil horizons.
Table 5. Soil taxonomic classification of each soil series in Iloilo with interpretation.
44 Simplified to Key Soil Series
Soil Series
Taxonomic Classification Interpretation
Barotac Fine, kaolinitic (ca.), isohyperthermic, TYPIC KANDIUSTOX
This soil has fine texture and isohyperthermic temperature regime (>22°C). It is an Oxisol (-ox), which is an intensely weathered soil predominated by oxides from iron and aluminum due to repeated high precipitation and high temperature (-ust). It is a typical (typic) representative of the great group Kandiustox. It has low cation exchange capacity (CEC) (kandi-), thus has low fertility status.
Faraon Fine, isohyperthermic, LITHIC HAPLUSTOLLS
Fine-textured soil (35-60% clay content) and has isohyperthermic temperature regime (>22°C). It is a Mollisol (-oll) - dark-colored, fertile soils with high base saturation and neutral to medium acid pH. It has minimum complexity in its soil horizonation (hapl-) found in areas with pronounced wet and dry seasons (-ust). It is a representative of the great group Haplustolls with lithic contact, specifically, it is a shallow soil with hard coralline limestone bedrock at 35cm depth.
Table 5. (continuation)
Iloilo 45
Soil Series
Taxonomic Classification Interpretation
Gui-maras
Fine loamy, mixed (ca.), isohyperther-mic, OXIC HAPLUS-TEPTS
This is a fine-loamy-textured soil with isohyperthermic temperature regime (>22°C). It is an Inceptisol (-ept), i.e. it is in the incipient development toward mature soil, but have not yet fully developed its diagnostic horizons. It has minimum complexity in its soil horizonation (hapl-) found in areas with pronounced wet and dry seasons (-ust) and a representative of the great group Haplustepts which has low CEC (oxic).
Luisi-ana
Very fine, kaolinitic (ca.), isohyperther-mic, USTIC PALEHUMULT
This is a very fine-textured soil with high clay content of >60% and has isohyperthermic temperature regime (>22°C). It is an Ultisol (-ult) which is a highly leached soil that has clay illuviation and low base saturation. It is a very deep (pale-) soil found in highlands (hum-) with pronounced wet and dry seasons (ustic).
Table 5. (continuation)
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Soil Series
Taxonomic Classification Interpretation
San Rafael
Fine, smectitic (ca.), isohy-perthermic, TYPIC PA-LEUSTULTS
This is a fine-textured soil with high clay content of >60% and has isohyperthermic temperature regime (>22°C). It is an Ultisol (-ult) which is a highly leached soil that has clay illuviation and low base saturation. This is a typical (typic) representative of the great groups Paleustults which is very deep (pale-) occurring in areas with pronounced wet and dry seasons (ust-).
Sara Fine, smectitic (ca.), isohy-perthermic, TYPIC EPI-AQUEPT
It is a fine-textured soil (35-60% clay content) and has isohyperthermic temperature regime (>22°C). It is an Inceptisol (-ept), i.e. it is in the incipient development toward mature soil, but have not yet fully developed its diagnostic horizons. It is a typical (typic) representative of the great group Epiaquepts. It is saturated with water for repeated periods of time (aqu-) manifested by its grayish color with or without mottles.
Table 5. (continuation)
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Soil Series
Taxonomic Classification Interpretation
Sta. Rita
Fine, smectitic (ca.), isohyper-thermic, TYPIC EPIAQUEPT
It is a fine-textured soil (35-60% clay content) and has isohyperthermic temperature regime (>22°C). It is an Inceptisol (-ept), i.e. it is in the incipient development toward mature soil, but have not yet fully developed its diagnostic horizons. It is a typical (typic) representative of the great group Epiaquepts. It is saturated with water for repeated periods of time (aqu-) manifested by its grayish color with or without mottles.
Umin-gan
Loamy skel-etal, mixed (ca.), isohy-perthermic, FLUVENTIC HAPLUSTEPT
Loamy skeletal-textured soil with many gravels and pebbles present and isohyperthermic temperature regime (>22°C). It is an Inceptisol (-ept), i.e. it is in the incipient development toward mature soil, but have not yet fully developed its diagnostic horizons. This soil has minimum complexity in its soil horizonation (hapl-) found in areas with pronounced wet and dry seasons (-ust). It is a representative of the great group Haplustepts which is subject to seasonal river flooding (fluventic).
Table 5. (continuation)
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Appendices
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Choose a vacant area in your field. Using a spade/auger, dig up to 50cm from the soil surface.
Depth of soil is impor-tant. The surface/top soil is not a good basis since it is always culti-vated.
Get bulk soil sample (½ kilo) from 30-50cm depth; place it in a container (plastic/pail). This sample will be used for soil series identification.
1 Soil sampling
APPENDIX 1. STEPS TO IDENTIFY SOIL SERIES
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2 Soil color determination
Soil color is an indi-rect measure of other characteristics such as drainage, aeration, and organic matter content. Black-colored soils may indicate high fertility and productivity.
Get an ample amount of soil from the sample. The soil should be moist (neither too wet, nor too dry).
Gray indicates a fairly constant water-saturated condition. Bright brown and red colors are indicative of good aeration and drainage.
Compare the color of the soil sample with the color chart in the guidebook. Take note of the classifica-tion of the soil color.
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3 Texture determination
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Get soil sample from a 30-50cm depth. Fill the test tube with soil sample up to the scratch mark.
Add 7 drops of CPR (chlorphenol red). Mix by gently swirling the test tube.
If soil pH is 6 or greater, repeat the steps using BTB (brom thymol blue).
If the soil pH is 5 or less, repeat the steps using BCG (brom cresol green).
Match the color of the solution on top of the soil with the corresponding color chart of the pH indicator dye used.
pH Determination (UPLB procedure)4
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APPENDIX 2. THE PALAYCHECK SYSTEM
The Palaycheck System is a rice integrated crop management that combines the technologies and learning processes to identify strengths and weaknesses of current crop management practices, make improvements in the next season to increase grain yield, input use efficiency, and profit with environmental concerns.
The PalayCheck System describes the crop management practices (input) to achieve the following Key Checks (output):
1) Used certified seeds of a recommended variety.
2) No high and low soil spots after final leveling.
3) Practiced synchronous planting after a fallow period.
4) Sufficient number of healthy seedlings.
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5) Sufficient nutrients at tillering to early panicle initiation, and flowering.
6) Avoided excessive water or drought stress that could affect the growth and the yield of the crop.
7) No significant yield loss due to pests.
8) Cut and threshed the crop at the right time.
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Badayos, R. B. 1990. Lowland rice soils in the Philippines, their characteristics and classification in relation to productivity. Inaugaral Professorial Lecture. SEARCA, UPLB.
Beinroth, F. H. 1978. Some fundamentals of soil classification. In: Soil-resource data for agricultural development. Ed. Leslie D. Swindale. Hawaii Ag. Expt. Sra., College of Trop. Agric., University of Hawaii. p.12-19.
MI Harpstead, TJ Sauer, and WF Bennet. 1997. Soil Science Simplified. 3rd Edition. Iowa State University Press, Ames Iowa 50014.
“Simplified Keys to Soil Series (29 Soil Series for Maize Production), Lop Buri Province” The International Training Workshop on “Applying Information Technology for Site-Specific Agriculture in Small Farms of Tropics.” August 4-10, 2003. Bangkok, Thailand.
Soil Survey of Iloilo Province. Department of Agriculture and Natural Resources, Bureau of Soils, Manila, Philippines. Bureau of Printing Manila.
Soil Survey Manual. US Department of Agricultural Handbook No. 18. August 1951.Soil Survey Staff, Bureau of Plant and Industry, Soils, and Agricultural Engineering. Agricultural Research Administration, US Department of Agriculture.
References
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Subject Matter Specialists
PhilRice®Wilfredo B. ColladoJesiree Elena Ann P. Dela TorreMary Rose O. ObicoRona T. DollentasConstancio A. Asis, Jr, PhDJovino L. De DiosEvelyn F. JavierLeo C. JavierEduardo Jimmy P. Quilang, PhDMadonna C. Casimero, PhD
UP Los BañosRodrigo B. Badayos, PhDArmando E. Soliman
Provincial Agriculture Office of IloiloIldefonso Toledo, PhDEly SandigAurea DelicanaMerlie Camarino
Managing Editor/Layout Artist Erik-Ray Matthew S. Palomar Editorial Advisers Leocadio S. Sebastian, PhD Ronan G. Zagado
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