SOILS OF KIRIMA KIMWE FACULTY OF AGRICULTURE FARM
Transcript of SOILS OF KIRIMA KIMWE FACULTY OF AGRICULTURE FARM
REPUBLIC OF KENYA
MINISTRY OF AGRICULTURE
SOILS OF
KIRIMA KIMWE FACULTY OF
AGRICULTURE FARM
By
N.N. NYANDAT and D.O. MICHIEKA
Soil Survey Unit
Nationr Agricultural Laboratories.
( i )
C O N T E N T S
ISRIC USPÎARY
JLÊ. OO . O M
Wageningen, Th» Notherlands
1. INTRODUCTION
2. GENERAL FEATURES OF THE FARM
Geology, Landscape and Soil Genesis
Clinlate
Drainage system and the quality of waters
3. THE SOILS
The method of investigation, the classification
system and Tarminology used
Description of the typical profiles and
Analytical data
k. PEDOLOGICAL FEATURES OF SIGNIFICANCE IN THE FARM
Slope and Soil erosion
Depth of soil and S ;oniness
Drainage, Permeability and Available moisture
Clay mineralogy
Nutrient availability
5. SUMMARY
6. REFERENCES
7. APPENDICES
I Analytical data for aug it samples
II Abbreviations; and the Nutrient deficiency
standards at the National Agricultural Laboratories
III One soil map sheet
iage
1
1
2
k
22
23
23
25
26
27
28
29
60
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5^3
( i i )
Pa£e
TABLES 1 ]_#Mean monthly rainfall for the Veterinary
laboratories which lies 0.5 kilometers
south west of the farm 3
2. Water analysis k
3. Data for a typical soil 1 S6
k. Data for a typical soil 2 '9
5. Data for a typical soil 3 11
6. Data for a typical soil *f 13
7. Data for a typical soil 5 15
8. Data for a typical soil 6 17
9. Data for a typical soil 7 19
10. Data for a typical soil 8 21
11. Moisture retention and moisture availability 2*f
12 Range of Available nutrients 26
THE SOILS OF THE, KIRIMA KIMWE FACULTY ..OF AGRICULTURE FARM
1. I N T R O D U C T I O N
The Faculty of Agriculture Farm is partly composed of land known as
Kirima Kimwe Estate and partly of land acquired from the Kenya Government»
The farm is situated in Upper Kabete at an. altitude of 19^0 metres and by
computation the area surveyed approximates 259 hectares. It lies about
8.5 kilometres north west of the University Campus and 1 kilometre north
of the Nairobi-Nakuru road. Mathari river forms most of the northern
fence-line but in the extreme east, a small portion of the farm adjoins
the lower Kabete road. The whole farm may be considered to lits within
latitudes l°lV20"S to 1°15'15"S and longitudes 36°Vf'E to 36°/+5'20"E.
Although the farm at present contains some 56 hectares of coffee,
10. f hectares of napier grass and *f.8 hectares of timber, no soil map exists
for the farm which is only covered by the soil map of Kenya compiled by
Gethin-Jones and.Scott (1958) on a scale of 1:3»000,000 and the map by
Scott (1961) on a scale of 1:50,000. The former map places the farm under
one soil namely Red to Strong Brown Friable Clay with Laterite while the
latter map places it under a Red Friable Clay. These soil maps being too
broad are inadequate for detailed information and therefore a soil survey
was commissioned to determined in detail the soils of the farm together with
their chemical and physical status with a view to future siting of
experiments and farm management in general. Eight soils have accordingly
been delineated on approximate scale of 1:2,850 and complete discussion
together with analytical data provided for4 each soil unit. Some chemical
and physical data for auger observations made in various parts of the farm
are also to be found in appendix I.
The users of the soil map and report are cautioned that the authors
may only guarantee accurancy in the spots actually examined on the ground.
The soil boundaries drawn across areas not seen at close hand may vary
to some extent from their actual position on the ground.
The authors wish to acknowledge the help rendered by both the staff
of the farm and the National Agricultural Laboratories during the
investigation.
2. GENERAL FEATURES OF THE FARM
Geology. Landscape and Soil Genesis.
Rocks of the farm comprise the Kabete Trachyte of the Middle Trachyte
Division of Tertiary age (Saggerson, E.P. - in press). These rocks
overlie the Kirichwa Valley Tuffs and the Nairobi Trachyte and are in turn
overlain elsewhere by the Karura and Limuru Trachytes. The Trachytes
which are grey-green are considered to have been a result of a narrow lava
flow erupted from the Muguga-Limuru area.
.../2
- 2 -
In recent times, geological processes have been limited to soil
formation and excarvation of valleys. In the region of the farm, landscape
consists of somewhat broad convex to flat ridges separated by steep sided
valleys which are subject to erosion if left bear. Within the ridges and
on the interfluves shallow depressions occasionally occur. During the
rains water seeps from the surrounding areas into these shallow depressions
but without adverse effect. In contrast the major valleys of Mathari
river and'the deep depression of the area of soil 7, become waterlogged.
The alternating ridges and valleys as may be xpected give rise to
contrasting soils with the better drained soils on ridge tops.and slopeçj
and the poorly drained soils in the low-lying valley beds. The well
drained soils are products of weathering óf the Trachyte under relatively
high temperature and rainfall. The weathering has produced reddish soils
that in places reach more than 15 metres thickness. The red soils of the
Nairobi are, as revealled from the studies by Dumbleton (l9é7) and Sherwood
(1967)» are because of leaching, depleted of soluble bases and silica
to provide a soil rich in iron oxide, hematite and geothite besides
aluminium in the form of clay minerals, metahalloysite and hydrated
halloysite. The red soils are further considered to possess clay particles
that are cemented together by free iron oxide.
The poorly drained soils (soils 7 and 9) of the farm, on the other
hand, result from the accumulation of the leached products from the upper
ground under conditions of impeded drainage. The clay mineral of these
soils are dominated by the expanding type of clay mineral (montmorillonite).
Climate
The farm (elevation 1,9^0 metres) falls within the Kikuyu grass zone
(15^0-2000 metres)« This is the zone where the indegenous Kikuyu grass
is considered to thrive well« The weather is cool in the months of
June, July and August and warm in the months of November, December and
January. Mean annual rainfall recorded over 4 5 years upto i960 for the
Veterminary Laboratories which lies 0.5 kilometres south west of the farm,
is 99O.6 mms. Table I below gives the rainfall distribution recorded for
the same place over the last 11 years. The rains appear well distributed
with April, May, October, November and December being the wettest months.
January, February, June and July however appear to be the driest months.
m i " /3
- 3 -
TABLE I: Mean Monthly Rainfall (mms) for the Veterinary Laboratories which li
0.5 kilometers south west of the farm.
1959 I960 1961 1962 1963 1964 1965 1966 1967 1968 1969
January 24.9 41.1 1.5 200.7 87.4 46.7 74.9 149.6 0 0 82.4
February 160.3 6.6 11.7 42.2 55.1 126.7 7.9 51.6 8.9 123.2 86.2
March 35.8 24?. 7 77.2 39.6 103.4 55.9 23.4 20.6 24.1 209.5 103.7
April l4l.5 192.3 176.0 184.7 402.1 451.1 324.9 223.3 290.I 4o.l 237.0
May 346.5 108.5 151.9 296.9 454.4 134.4 79.8 113.5 496.3 184.5 .. 119.2
June 44.2 33.3 29.0 58.4 33.5 17.0 4813-' 41.4 3Î** 48.0 3.4
July 92.7 6.6 32.3 3.8 2.0 27.9 14.2 4.1 26.9 5.8 6.0
August 0.5 9.7 37.6 4o.l 64.5 70.4 10.2 64.8 51.1 6.4 39.5
September 7-6 32.8 47.8 9.4 18.8 11.4 6.9 19.6 44.2 5-8 8.6
October 10.2 78.7 177.3 85.6 12.4 29.5 88.6 46.5 113.0 51.7 32.4
November 54.6 75.7 547.9 117. 6 *n.2 98.2 142.5 167.9 125.7 110.5 285.I
December 54.6 33.0 369.8 126.2 332.5 93.7 162.8 48.8 39.6 14.3 : 163.3
Total 973.4 866.0 1660.O 1205.2 1737.3 1142.9 984.4 951.4 1257.O 799.8 1166,8
- *f -
Drainage system and the Quality of waters
The drainage system follows topography of the farm.. During the
rains excess water drainasfrom the higher ground to the lowlying areas and
then into Mathari stream which is the main drainage outlet for the area.
Most of the depressions within the ridges may benefit from the seepage
nutrients and moisture, but the depression of soil 7 and the valleys of soil
9 are clearly adversely affected. The latter are either seasonally
waterlogged because of subsoil drainage impedence or are swampy because
of too high water table.
At present the source of water for irrigation and domestiècuse
is the Mathari river which is pooled for pumping in the north eastern
corner of the farm. This water has been tested at three points namely
upstream, at stream entry to the dam and at the dam. Also tested is the
water from the pool near the Coffee Factory. Table 2 gives the results
of the tests.
TABLE 2; Water analysis
Description
1. Up Mathari stream (at junction of western
boundary and the stream)
Laboratory No,
2.. At stream entry to the main dam
3» At main dam
4, Small pool near coffee factory
7229/70
7228/70
7226/70
7227/70
pH 7.5 7.1 7.9 6_9
EC micro mhos/cm 350 360 360 350
Na m.e./l 0.66 0.67 0.71 0.:69
K » 0.16 0.18 0.21 0..19
Mg 0.33 0..40 0.57 0.57
HCO3 " 0.18 0.18 0.17 0.18
Ca " 0.7^ c'a 0.66 o.4o CO, » Nil Nil Nil Nil
CI ' " 0.16 O..I6 0.16 0.17
SO3 " Nil Nil Nil Nil
K. S• C • Nil Nil Nil Nil
S.A.R. 0.90 I.05 0.96 0.99
According to the United Spates Handbook N0.6O (1951) these waters
are free from salinity and alkalinity hazard. There also seems to be
no marked change in the water quality downstream as far as the soluble,
macro-elements are concerned» The waters may therefore be safe for
irrigation.
3. S H E S O I L S
The Method of Investigation, the classification „system. _and_ _T.e rminol.ogzJJsed,
Vertical «Wptel photographs for the farm were examined in detail and
tentative soil boundaries drawn using variations in topography, photograph-
tone and photograph texture. A grid system with 200 metres by 100 metres
interval was then laid for auger spot observations. These auger .borings. •••/5
- 5 -together with pits dug in representative sites were morphologically described
in detail and sampled according to evident distinction in soil horizon
morphology. The soils were chemically and physically analysed and the results
together with those of the profile description used to draw the final soil
boundaries.
The soil classification and mapping unit employs a "soil phase"
(United State 7th Approximation, 196*0 with factors of drainage, colour,
texture, depth of soil, stoniness and slope being the ones used. These soil
phases are simply outlined in the soil map legend without relating them to
a higher category in the now popular United States 7th Approximation
(revised 2nd edition, 1967). This is because the analytical methods currently
available at the National Agricultural Laboratories are not sufficiently
complete to allow the soils to be fitted into this classification system. For
instance, the field examination indicates that almost all of the soils of the
farm contain what appears to be translocated clay (clay skins). It may,
therefore, be necessary to confirm by micromorphological analysis (thin sections
whether these are really clay skins or just pressure caused smooth
/a higher category in the United States
system may be -attempted. Also a more accurate determination of clay percen
tage may have to be effected by the pipette method for purposes of precise
estimation of the cation exchange capacity which is very vital for the
classification of these soils. However the correlation at higher category
in the United states elassification system may be done at convenience
without invalidating the present soil units since the present classification
is at very low category namely the soil phase. The soil profile description
terminology follows that of the United States" Soil Survey Manual (1951)
whereas the colours relate to the Munsell Colour Chart (195^) and are for
moist soil unless otherwise indicated.
The mechanical analysis was performed by the hydrometer method and the
texture grades are according to the United States texture triangle. The
C.E.C. and exchangeable bases were determined by the ammonium acetate method
while the determination of carbon is by the Walkley and Black method; nitrogen
was determined by Kjeldahl method. The available nutrients and other analyses
were performed by the methods of Mehlich et al (1959) currently in use at the
National Agricultural Laboratories.
Description of the Typical profile and Analytical data
This section outlines the salient morphological, chemical and physical
features of the soils that occur in the farm. The section also contains
analytical data and profile description of the typical profiles,
SOIL 1
This is a dark reddish brown clay which overlies a dark red clay. The
soil derives from Kabete Trachyte and occupies slopes less than 8 and inter7
fluves. It is deep and well drained. It consists of a blocky structure with
good root development. Earth worm channels are common feature of this soil
and evidence of translocated clay (clay skins) is present from l6 cms and continues into the deep subsoil.
- 6 -
LaEüTIÜNr Observetion point No.if TABLE 3 iAB.NO.7122-7124/70
PIT N0.16 SOIL 1
CMS DEPTH
% C
of 70 Eand
% S i l t
tf Bulk MOISTURE ?.' m . e . % EXCHANGEABLE Bf, iSES m . e . # E . S . P . CMS DEPTH
% C
of 70 Eand
% S i l t C lay D e n s i t y
gm/cm* 1/3-kirn. 15 'Atm C . E . C . Ca Mg K Na
E . S . P .
0 - 1 6 3 . 6 2 3 5 26 59 0 . 8 6 43.4 2 6 . 5 3 4 . 2 1 2 . 8 0 3 . 0 5 2 . 8 5 C.40 1 .2
16*56 - 5 20 75 1 . 0 2 44.4 2 7 . 4 3*.8 1 0 . 8 0 2 . 2 5 2 . 3 0 C.30 1 .0
56+ - 9 10 81 I . 0 7 4 6 . 2 2 9 . 0 2 6 . 0 2 . 8 0 2 . 8 5 0 . 3 0 0 . 4 0 1 .5
CMS DEPTH
pHl*5 B2° pH £r5
KCl
k*3JEC.l:5 m.mhos/
cm
11
Hp i . e . #
Hv AVAI] Mn
U-.BLE NUTRIENTS m. •Ka fcX fCa Mg Bifc .Tes t Cann-# P l u s a l l
H J P S P ppm
% N
O-I6 6 . 4 5 . 6 0 . 0 7 - - l . l t 0 . l 4 I . 2 6 7 . 4 0 3 .5C 40 60 92 12 0 . 4 4
I 6 - 5 6 6 0 5 . 4 0 . 0 7 - - 0 . 9 0 O.O8 1 .04 3 . 6 0 2.6O M * «M * * - 10 -
56 + 5 . 0 4 . 3 O.O5 1 . 3 - O.58 O . I6 O.06 0 . 4 0 2 . 9 0 •* *« - 6
?or # orgaaic matter, multiply % C fcy 1.73
- 7 -
The clay mineral is predominantly kaolin which appears to be poorly
crystallised äs evidenced by the low intensity and broadness of the peak.
The kaolin is possibly a metahalloyfeite. The soil also contains about
15 percent illite with traces of 2:1 type of clay mineral. The water
receptiôïïn of this soil is fairly high and lies in the region of 3^5 mms
per hour* The available moisture in the first 60 cms of soil averages
about 17 per cent (Table II).
This soil which is dominant in the farm has a topsoil pH ranging
between 5.2 and 7.2 with a subsoil pH in the range of 5.2 to 7.7 (Table 12)-,
The available nutrients K, Ca, Mg Mn and P range from deficiencies to
fairly high levels. The nitrogen however seems sufficient by standards
at the National Agricultural Laboratories (Appendix II)
The soil profile in observation point N0.l6 is typical of this class
of soils and Table 3 provides the analytical data.
PIT N0..16
LOCATION;
SLOPE:
MICRO-RELIEF:
PARENT MATERIAL:
ROOTING DEPTH:
Profile description»
Observation site No.l6
Nearly level.
Even
Kabete Trachyte
More than 158 cms.
MAXIMUM ROOT. DENSITY: 0-l6 cms
SOIL DEPTH:
DRAINAGE:
LAND USE:
0-l6 cms
I6-56 cms.
56-158 cms+
More than 158 cms.
Good
Coffee Plantation
Dark reddish brown (5ÏR 3/3) clay which is sticky
when wet, slightly hard when moist and hard when dry.
The structure is blocky and consists of moderately
developed medium peds. Fine roots are many while
medium and coarse roots are few. The horizon is
porous and earthworm channesl and whitish decayed
roots are evident. The lower boundary is smooth and
clear.
Dark reddish brown (lOYR3/^)st icky clay which is firm
when moist. The structure which is blocky consists
of very fine, fine, and medium peds which are
moderately developed. Clay skins are distinct and
common. Fine, medium and coarse roots are common.
The horizon which is very porous contains worm channels
and whitish decayed roots. The lower boundary is
smooth and diffuse.
Dark red (2.5 YJR 3/6) sticky clay whose structure
is blocky. The medium peds which are slightly
firm when moist are moderately developed. Very
fine manganese concretions are occasionally evident.
Clay skins are distinct and common. Fine .../8
- 8 -roots are few. The horizon is less porous and
contains few earth worm channesl.
SOIL 2.
Soil 2 is a dark reddish brown clay which overlies a dark red clay»
The soil is found in fairly large depressions which occur in interfluves.
It is derived from Kabete Trachyte and is well drained although may be
expected to receive seepage materials from the higher lying grounds. The
soil is deep and consists of blocky structi-.re. The root development on
these soils is good. Krotovinas and earthworm channels are commonly met
in the soils. Clay skins occur from 30 cms and continue into the deep
subsoil.
The clay mineral composition is similarly to that of soil I and the
available moisture in the top 50 cms of soil averages about 10.5 percent.
This is low compared to that of Soil 1 perhaps because of the relatively
low water holding capacity of this soil. Topsoil pH ranges between
3.7 and 7.7 whereas that of the subsoil ranges from 6.1 to 7*7» The
topsoil nutrients are generally better available than in soil I and
deficiency is encountered only in the case of phosphorus .
Soil profile in observation point No.13 represents this class of
soils and the analytical data are provided in Table l4.
PIT NO.15:
LOCATION;
SLOPE:
MICRO-RELIEF:
PARENT MATERIAL:
ROOTING DEPTH:
MAXIMUM ROOT DENSITY;
SOIL DEPTH:
DRAINAGE:
LAND USE:
0-26 cms,
26-50 cms.
Profile description
Observation point No.13
Depression
Even
Kabete Trachyte
More than ikk cms0
0-20 cms.
More than lkk cms
Good
Coffee Plantation
Dark reddish brown (5YR 3/^) sticky clay which
iis very firm when moist. The micro-structure
consists of weakly developed fine granules which
are compounded into a blocky macro—structure
consisting of moderately developed medium peds.
Fine and medium roots are many whereas coarse
roots are rare. Krotovinas and earthworm channels
are present. The lower boundary of this very
porous horizon is smooth and diffuse.
Dark reddish brown (.2.5fâ£K0? sticky clay whose
structure is blocky. The t>. ds which are fine
and medium are moderately developed and are very
firm when moist. Clay skins are distinct and common«
Fine and medium roots are few while coarse roots
are rare. Krotovinas and earthworm channels are
present. The lower boundary is smooth and diffuse.
.../9
_ 9 -LOCATION: Obse rv î t i on po in t No.13 TABLE 4 LAB.NO.7118-7121/70
PIT WO.13 SOIL 2
CHS • DEPTH
% C
% Sand
% S i l t
% Clay
B u l k D e n s i t y gm/cm
MOIS 1/3/AtnJ
TÜRE % 15Atm
m.e .% C . E . C .
EXCHANGEABLE BASES m . e . Ca ."Mg K Na
E . S . P .
O-26 O.S8 17 26 57 1 . 0 1 3 5 . 2 2 4 . 8 3 0 . 8 1 5 . 2 0 2 . 0 0 1 .15 O.3O 1 .0
26-5O - 13 2k S3 L O S 3 6 . 7 2 6 . I 3 4 . 2 l 6 . 4 0 1 .50 0 . 5 5 0 . 4 0 1 .2
5 0 - 9 1 - 1 3 22 *5 I . O 8 3 8 . I 2 6 . I 3 2 . 0 1 3 . 6 0 O.7O 0 . 0 5 0 . 4 0 1 .3
91+ • M 1 16 83 - <- - 2 7 . 4 1 2 . 0 0 I . 8 0 0 . 4 0 0 . 5 5 2 . 0
CMS DEPTH
)H 1 : 5 H 2 0 pH 1:5 EC 1:5
numhos/ cm
Hp m . e . %
H T AVA
Mn ILABLE
Na NUTRIENTS n K Ca Mg
B i o . T e N
s t Cunn-P
£ P l u s a i l S
p ppm
% N
O-26 S.l 5.1 0.03 - - 0 . 9 0 0 . 1 0 0 . 6 8 1 0 . 0 2 . 1 0 38 45 ( 6 10 0 . 3 7
2 6 - 5 0 è.5 5.5 0.04 - - O.38 0 . 1 4 0 . l 4 9 . 2 I . 8 O - - - 1 1 -
5 0 - 9 1 6 , 2 5.6 0.04 - - O.67 O.16 0 . 0 9 5 . 2 1 . 5 ^ - - - 10 «•
91+ 0.7 5.6 0.07 - - 0 . 5 1 O . I 6 O.O6 3 . 0 2 . 3 0 - - «• 1 0 -
For "6 organic matter, multiply % C by 1.73
50-91 cms.
91-lHcms+
- 10 -
Dark reddish brown (2.5 YR3/^)clay which is sticky
when wet. The structure is blocky and consists of
moderately developed medium peds which are firm
when moist. Fine and medium roots are few while
coarse roots are rare. Krotovinas and earthworm
channels are present. Clay skins are faint and
few. The lower boundary is smooth and diffuse.
Dark red (2.5 YJR 3/6) sticky clay whose structure
is blocky. The medium peds which are slightly
firm when moist are moderately developed. Very
fine manganese concretions are present but rare«
Clay skins are faint and few. Fine, medium and
coarse roots are very rare. Krotovinas and earthwor
channel^ are present.
SOIL 3:
This is a dark reddish brown clay which overlies a dark red clay. The
soil occupies slopes 8 to 12° and derives from Kabete Trachyte, It is
well drained with blocky structure. The root development in this soil is
good and only few earthworm channels are present. There is evidence of
translocated clay in the subsoil.
The clay mineral consists of a kaolin type of clay mineral to the
exclusion of any other clay mineral. The spacing, the intensity and the
shape of the peek of this clay mineral may all appear to suggest the kaolin
is a metahalloysite. The topsoil pH ranges between 5.8 and 6.2 whereas the
subsoil pH ranges between 5.9 and 6.7. This soil therefore appears slightly
more leached than soils 1 and 2. The lower limit of available nutrients
seem comparable to those of soil 2 although the upper level is lower. The
nutrient levels except in the case of phosphorus do not suggest deficiencies
by the National Agricultural Laboratories standards.
A typical profile of this class of soils is that in observation point
No.A4,Table 5 gives the analytical data.
PIT NO.H:
LOCATION:
SLOPE:
ASPECT:
MICRO-RELIEF:
EROSIO»:
PARENT MATERIAL:
MAXIMUM ROOT DENSITY:
SOIL DEPTH:
DRAINAGE:
LAND USE:
Profile description
Observation point No.kk
9° East
Even
Expected
Kabete Trachyte
0-20 cms.
More than 157 cms.
Good.
Coffee Plantation.
.../Il
- 11 -
LOCAÏIONs Observation point No.44 TABLE 5 LAB.NO..7134-7136/70
PIT NO.44 SOIL 3
CHS
0. %
Sand % % m . e . # EXCHANGEABLE BASES m . e . # E . S . P .
DEPTE 0. %
Sand S i l t C lay C E . C. Ca Mg K Na
E . S . P .
0 - 2 0 4.44 9 24 67 36 .O 1 1 . 2 0 2.85 4.05 0 . 3 5 1 .0
2 0 - 6 6 - 4 12 84 1 9 . 0 4.4o Trace l . « 0 0 . 2 0 1 .1
66+ - 1 3 10 80 2 2 . 2 8.80 I . 7 0 HS H° 1 .3
CMS DEPTH
pH I1.5
H 2 0 pH 1 :5 KCl
EC 1*5 m.mhos /
cm
m H ,
. e mjo
Hv AVAILS Mn
,BLE NUTRIENTS Na K
m . e . # Ca Mg
B i o . T e s t Cunn-# N P
P l u s a l l S
? ppm
#N
C-20 6 . 0 4.9 O.O7 • M - 1 .22 O.O6 2 . 0 0 5 . 2 0 3 . 3 0 50 67 96 10 0.48
20-66 5 . 2 4.4 O.05 1 .10 *•» ê.66 T r a c e •...44 1 .00 I . 8 O - - - 6 ~
66+ 6 . 0 5.&" 0 . 0 4 - 0 . 7 2 T r a c e 0.75 2 . 0 2 . 1 - - 9
— ,. - .
For jf organic matter, multiply % C by 1»73
O?20 cms.
20-66 cms,
66-157 cms +
*- 12 -
Bark reddish brown (5 YR 3/3) sticky clay whose
structure is blocky. The medium peds are moderately
developed. They are hard when dry and very firm
when moist* Medium and coarse roots are common*
While fine roots are few. The lower boundary is
smooth and diffuse.
Dark reddish brown (2,5 YR 3/3) clay which is sticky
when wet. The structure is blocky and consists of
moderately developed medium peds which are firm
when moist. Few faint clay skins are present and
reaction on matrix is very slight. Medium roots are
common while coarse roots are few. Few earthworm
channels are present. The lower boundary is smooth
and diffuse.
Dark red (2.5 YR 3/6) sticky clay whose structure
is blocky. The peds which are firm when moist are
medium and are moderately developed. The reaction
on matrix is very slight. Clay skins are few.
Earthworm channels are also few.
SOIL hi
This is a dark reddish brown clay which overlies a dark red clay. The
soil • is found on 8 to 12° slopes and contains rock within 120 cms. It is
well drained and consists of a blocky structure. This soil which derives from
Kabete Trachyte supports good root development and contains few faint clay
skins below 30 cms. The clay skins however become rare with depth.
The clay mineralogy of this class of soils predominantly consists of
kaolinite with traces of ill defined illite. The topsoil pH ranges between
5.8 and 6,1 whereas the subsoil pH ranges between 5.6 and 6,3« Deficiencies
of K» Ca, Mg, Mn and N are not encountered with this class of soils but .
P seems to be on the very low side.
Soil profile in observation point No,38 is typical of the class k soil»
Table 6 provides the analytical data.
PIT NO.38:
LOCATION;
SLOPE:
ASPECT;
MICRO-RELIEF:
EROSION;
EàBjatT V'TU.lïU
ROOTING DEPTH:
MAXIMUM ROOT DENSITY:
SOIItPBPTH:
DRAINAGE:
Profile description.
Observation point No,38
12°
East
Even
Expected
Kabete Trachyte
Less than 120 eras,
O-28 ems«
Less than 120 cms.
Good
....A3
- 13 -
LOCATION:. Observation point No.38 TABLE 6 LAB.NO.7137-7139/70
PIT NO. }8 SOIL 4
CMS DJSLPTH
% # % % m.e./B EXCHANGEABLE BASES m. e •% E . S . P . CMS DJSLPTH c Sand S i l t C lay C E , C. Ca Mg K Na
E . S . P .
O-28 3 . 8 8 12 20 68 2 9 . 0 1 2 . 8 0 I . 8 5 1 . 2 5 • . 2 5 0 . 9
2 8 - 4 8 - 32: 12 56 2 3 . 4 8 . 4 0 2 . 4 5 1 . 2 5 0 . 2 0 0 . 9
if 8 + - 4 14 82 2 1 . 2 1 .60 I . 5 0 0 . 4 0 0 . 2 0 1 .0
CMS DEPTH
p H - U S flgO
\ pH 1 :5
KCl EC 1 :5 m.mhos /
cm
m Hp
• e,#> Hv
AVAII Mn
.ABLE NUTRIENTS m . e . # N a K Ca Mg
B i o . T e s , N
t Cunn-# P
P l u s f a l l S
P ppm
SéN
C-28 6 . 1 5 . 2 0 . 0 3 - - O.80 0.0*+ O.56 8.6O 2 . 4 0 48 kh 91 6 0 . 4 4
22V 2b-48 6 . 1 5 . 3 0 . 0 4 - <- O.62 T r a c e O.56 3.6O 2 . 3 0 p * - - 7 *•
if 8+ 5 . 0 4 . 5 0 . 0 4 I . 7 0 « 0 . 4 2 T r a c e 0 . 1 2 0 . 4 0 I . 8 O - 6
For # organic matter, multiply %C liy 1.73
- 14 -
LAND USE;
VEGETATION:
0- 28 cms.
28-48 cms.
48-109 cms.
Nil
Bush and grass
Dark reddish brown (5YR 3/3) clay which is sticky
when moist. The structure is blocky and consists
of moderately developed very fine and fine 1
peds which are firm when moist and slightly hard '
when dry. Fine roots are many while medium roots
are common and coarse ones few. The lower boundary
is smooth and clear.
Dark reddish brown (2.5 YR 3/4) sticky clay with
a blocky structure consisting of moderately
developed fine and medium peds. The peds are very
firm when dry and firm when moist. Faint clay
skins are few. Fine roots are common while medium
and coarse roots are few. The lower boundary is
smooth and diffuse.
Dark red (2.5 YR 3/6) clay which is sticky when wet.
The blocky structure consists of moderately developed
medium peds which are firm when moist. Faint clay
skins are present but rare. Fine and medium roots
are common while coarse roots are few. Small
stones are present but rare. The lower boundary
is wavy and abrupt.
109 cms. + Rock present.
SOIL 5:
Soil 5 is a dark reddish brown clay which overlies a dark red clay.
The soil occupies slopes more than 12° and is well drained. It is deep
and derives from Kabete Trachyte. The structure is blocky and earthworm
channels are common occurrence in this soil.
Like soil 4, the clay minerals predominantly consist of kaolinite with
traces of ill-defined illite. The available nutrients range from deficient
to moderate levels but phosphorus is commonly deficient. The topsoil and
subsoil pH ranges are respectively 5»2 to 6.6 and 4.8 to 6.5.
Soil profile in observation point No*6l represents these soils and
Table 7 gives the analytical data.
PIT NO.6l:
LOCATION ;
SLOPE;
ASPECT:
MICRO-RELIEF:
EROSION :
PARENT MATERIAL:
ROOTING DEPTH:
MAXIMUM ROOT DENSITY:
Profile description
Observation point No.61
20°
North
Even
Expected
Kabete Trachyte
More than 163 cms.
0-23 cms.
15
- 15 -
LOCATION: Observat ion p o i n t No.6 l TABLE 7 LAB.N0.7152-715V70
PIT NO.6l SOIL 5
CMS DEPTH C
% % % m.e, % EXCHANGEABLE BASES nue. % E.S.P. CMS DEPTH C Sand Silt Clay C E . C. Ca Mg K Na
C-23 3.56 10 22 68 21.2 4.8O 2.15 • 1*55 0.20 1.0
23-^9 - 4 22 .7* 21.2 6.00 2.O5 1.50 0.20 1.0
^ + - 6 16 78 I6.O O.8O I.70 0.70 0.10 0.6
CMS DEPTH
p3 H5 H23 pE 1:5
KCl EC lt5 m.mhos/
cm
m,e,% AVAILABLE NUTRIENTS m.e.g Bio.Test Cunn-# Plus all P ppm
% N CMS DEPTH
p3 H5 H23 pE 1:5
KCl EC lt5 m.mhos/
cm Hp Hv Hn Na K Ca Mg N P s
P ppm
% N
0-23 5.9 4.9 C.05 « • - 1*16 0-f 06 . 1*10 4.4o •2.90 - 56 48 63 l4 0.46
23-49 5.9 .9 0.03 - - 0.55 0.l4 O.6O I.80 2.60 — •
- 16 -
49+ 6.0 4.3 0.04 1.20 - 0.02 Trace 0.22 o.4o 2.43 - 16
For % organic matter, multiply % C by 1.73
SOIL DEPTH:
DRAINAGE:
VEGETATION :
0-23 cms
23-i*9 cms.
^9-163 cms +
- 16 -
More than I63 cms.
Good
Plantation trees, herbs and grasses.
Dark reddish brown (5 YEJ 4)sticky clay with
a blocky structure. The fine and medium peds
are moderately developed and are firm when
moist. Eine, medium and coarse roots are common.
Few earthworm channels are present.
Dark reddish brown (2.5 ÏI.3y?4)clny which is sticky
when moist. The structure is blocky and consists
of moderately developed medium peds which are firm
when moist. Few faint clay skins are present.
Fine and medium roots are common while coarse
roots are few. Earthworm channels are common
and reaction on matrix is very slight. The lower
boundary is smooth and diffuse.
Dark red (2.5 YR 3/6) sticky clay with a blocky
structure consisting of moderately developed
medium peds which are firm when moist. The
reaction on matrix is very slight. Clay skins
are faint and rare. Fine, medium and coarse
roots are few. Earthworm channels are common.
SOIL 6:
This is a dark reddish brown clay which overlies a reddish brown to dark
red clay. The soil has a periodic high water table and appears to lie in
a seepage line. Like previous soils, it derives from Kabete Trachyte and
the structure is blocky. Organic matter granules are found in the tops'oil
and manganese concretions are a common feature of the subsoil.
The clay mineralogy is similar to that for soils 1 to 3' in that it
consists of kaolin which appears to be poorly crystallized. The kaolin is
possibly a metahalloysite. The available nutrients K, Ca, Mg, Mn and N
seem adequate but P is deficient.
Soil profile No.6 is typical of these soils. Table 8 gives the
analytical data.
Profile description
Observation point No.6
Depression
Even
Kabete Trachyte.
88 cms.
0- 2 cms.
More than 88 cms.
88 cms.
Seasonal high water table
PIT NO.6
LOCATION;
SLOPE;
MICRO-RELIEF;
PARENT MATERIAL;
ROOTING DEPTH;
MAXIMUM ROOT DENSITY:
SOIL DEPTH;
WATER TABLE:
DRAINAGE:
LAND USE: Napier grass .. .A7
- 17 -
LOCATION: Observation point No.6 TABLE 8 LAB .NO. 7115-»7117/70
PIT NO.6 SOIL 6
CMS DEPTH
% C
% Sand
% Silt
% Clay
m .e. % EXCHANGEABLE BAS 3S m.e. % * E.S .P. CMS DEPTH
% C
% Sand
% Silt
% Clay C.E.C. Ca Mg K Na
0-23 3.83 15 42 43 38.0 13.60 2.05 2.40 0.55 1.5
23-42 - 11 30 59 34.2 9.40 .1.00 0.55 0.90 2.6
42+ - 3 22 69 24.0 4.00 0.70 0.30 0.95 4.0
CMS' DEPTH
pH 1:5
pH 1:5 KCl
EC l.njj, m.mhos/ cm
m. Hp
e. % Hv
AVAILABLE NUT Ma Na
BIENTS m.e.':#>. K Ca Mg
Bio. 7
N
lftstiCunn-Plus all P S,
P,; i ppm N
0-23 6.2 5.2 0.07 - *» 1.02 0.21 1.34 8.40 2.30 43 39 97 8 0.42
23-42. 5.8 4.9 0.07 0.20 - 1.18 J.36 0.14 4.80 1.50 !•* - ' - 8 -
42 + 5.6 4.5 0.07 0.90 - 0.99 0.56 o.o8 1.4o
1 1.30 - *• - 6
—
For % »rganic matter, multiply % C by 1.73
0-23 cms
22dtL cms,
42-88 cms +
- 10 -
Dark reddish brown (5YR 3/3) clay with a blocky
structure. The medium peds are weakly developed
and are slightly firm when moist. Fine and
medium roots are many; Organic matter granules
are many. The lower boundary is smooth and g
diffuse.
Dark red (2.5 YR 3/6) clay whose structure is
blocky and consisting of weakly developed medium
peds which are slightly firm and moist. Fine
manganese concretions are common. Medium roots
are many. Patches of organic matter are common.
The lower boundary is smooth and diffuse.
Dark red (2.5 YR 3/6) sticky clay. The
structure is blocky and consists of moderately
developed medium peds which are firm when moist.
Fine manganese concretions are common. Fine
and medium roots are common. Water table occurs
at 88 cms.
SOIL ft
This is a dark brown to dark grey brown clay which occurs in a low
lying depression. The soil is seasonally waterlogged and derives from
Kabete Trachyte and colluvial material. The drainage is impeded with
permeability to v/ater in the region of 17 mms per 2k hours. The water
holding capacity (Table ll) is about similar to that of soil 1 but the
topsoil has more available water than that of soil 1.
The expanding 2:1 type of clay mineral (montmorillönite) predominates
in this soil. Also present is about 20 to 30 percent kaolin which appears
to be a metahalloysite. The impeded drainage of this soil may therefore be
attributed to the high content of montmorillönite which swells to seal up
on wetting. Indeed the swelling of the clay mineral was measured to be from
15.66 to 17.66 Ä. ' '
The topsoil structure'consists of fine and medium granul&a while the
deep subsoil structure is blocky. Sliokensides are observed in the third
and fifth horizons and the soil is devoid of roots below 100 cms. This soil
is only moderate in available nutrients although the nutrient holding
capacity is significantly different from those of the well drained soils.
The available phosphorus is clearly deficient. The topsoil pH is in the
region of 5»1 whereas the subsoil pH is about 5»3» The soil therefore
appears more acid than the soils already discussed.
Soil profile No.l8 is typical of these soils and Table 9 gives the
analytical data.
PIT NO.18: Profile description
Observation point N0.18
Depression
Ridged for drainage.-
.../19
LOCATION:
SLOPE:
MICRO-RELIEF:
-19 -LOCATIOÎ
PIT NO.3
I: O b s e r v a t i o n p o i n t No.
.8
18 TABLE 9 LAE .NO.7I25-7129/7O
SOIL 7
'CMS ;
DEPTE % C
% Sand S i l t
% c l a y
Bu lk D e n s i t y gm/cnr
MOISTURE % nr . e . % C.E.C
EXCHANGEABLE BASES m . e . % E . S . P . 'CMS ;
DEPTE % C
% Sand S i l t
% c l a y
Bu lk D e n s i t y gm/cnr
1/3 Atm 15 Atm nr . e . %
C.E.C Ca" Mg K Ha E . S . P .
0 -20 2 . 5 1 19 24 57 1 . 0 1 4 6 . 8 2 5 . 7 3 2 , 0 1 3 . 2 0 I . 2 5 0 . 9 3 3 . 7 5 2 . 3
2 0 - 4 9 - 13 24 63 1 . 2 3 3 9 . 8 2 5 . 2 1 7 . 2 1 3 . 2 0 I . 6 5 0 . 1 5 1 .20 7 . 0
4 9 - 8 4 ~ 1 1 24 65 1 .17 4 4 , 3 2 8 . 9 3 6 . 0 1 9 . 6 0 1 .20 0 . 5 5 2 . 0 0 5 . 6
8 4 - 1 0 4 21 18 61 • - - - 4 2 . 6 2 7 . 6 0 1 .55 O.85 2 . 4 5 5 . 8
1C4« - 11 10 79 - » • • - 5 0 . 4 3 6 . 0 0 1 .55 1.25' 2 . 7 5 5.5
CMS DEPTH •
pH 1 » 5
H20 pH , 1 : 5 KCL
EC 1 :5 m.mhos /
cm
m.. Hp
e..# Hv
AVAILABLE NUTRIENTS . Mn Na K
5 m . e . % Ca Mg
B i o . T e s t Cunn-# P l u s a l l
N . P S
P ppm
% N
0 - 2 0 5 . 4 . 4 . 2 0 . 0 4 1 .20 - 0 . 6 6 0 . 3 3 0 . 3 2 6 . 8 0 2 . 0 0 52 48 68 7 0 . 2 9
20 -49 5.6 4 . 3 0 . 0 4 0 . 5 0 - <•••'••€.32 0 . 5 9 0 . 1 0 6 . 4 0 1 .40 - - - 8 -
49-84 5 . 9 4 . 3 0 . 0 9 mm - »• .12 1 .04 0 . 1 2 9 . 6 0 I . 6 O *•» - - 10 •*•
8 4 - 1 0 4 6 . 2 4 . 7 0 . 1 3 - - • * . 3 9 1 .20 0 . 1 8 9 . 2 0 I . 6 O - - - 10 -
104+ 6.3 4 . 8 0 . 0 6 - - 0 . 0 5 1 .26 0 . 3 0 1 0 . 0 0 2 . 0 0 -•
-» 13 ,,
Eor # organic matter, multiply % Cky. I.73
- 2 V -
PARENT MATERIAL;
ROOTING DEPTH:
MAXIMUM ROOT DENSITY:
SOIL DEPTH:
DRAINAGE:
0-20 cms.
20-49 cms,
49~84 cms
84-104 cms,
104-156 cms +
SOIL 8:
Kabete Trachyte/Colluvium
More than 156 cms.
0-20 cms.
More than 156 cms.
Impeded (seasonally waterlogged)
Dark brown (lOYR 3/3) sticky clay whose structure
consist of moderately developed fine and medium
granules. The peds are fine firm when dry and-
slightly firm when moist. Distinct orange mottles
are many. Eine, medium and coarse roots are
many. The lower boundary is smooth and clear.
Grey brown (lOYR 5/2) very sticky clay with many
distinct yellow brown (5YR 5/6) mottles. The
structure consists of moderately developed fine
granules which are slightly firm when moist. Fine
roots are common. The lower boundary is smooth
and diffuse.
Dark yellowish brown (lOYR 4/4) very sticky clay
with a blocky structure. The coarse peds are
weakly developed and are very hard when dry and
slightly hard when moist. Faint slickensides are
present. Few fine gravel are also present. Fine
roots are common. The lower boundary is smooth
and clear.
Dark brown (lOYR 4/3) very sticky clay whose
structure is blocky and consists of weakly
developed coarse peds. The pede are very hard
when dry and hard when moist. Fine and medium
gravel are many. The horizon is devoid of roots«
The lower boundary is smooth and clear»
Dark grey brown (10 YR 4/2) very sticky clay with
blocky and subangular blocky structure. The peds
which are medium are moderately developed and
are very hard when dry and slightly hard when
moist. Distinct slickensides are present. Fine
gravel are occasional. The horizon is devoid
of roots.
Soil 8 is a colluvinm/alluvium which is swampy most of the year. The
soil occurs along stream channels and possibly derives from mixed parent ma
material (Kabete Trachyte/colluvium/alluvium). The soil contains many gravel
below 23 cms although the fraction less than 2 mm is predominantly clay.
The clay mineralogy is like that of soil 7» Montmorillonite predominates
with about 20 to 30 percent metahalloysite. The water holding opacity of
the soil is very high compared to those of other soils. It is however
lower in the deep subsoil because of the presence of much gravel. The
- 21 -
LOCATION« Observation point No.4l TABLE 10 LAB .NO. 7143-7145/70
PIT N0.4l SOIL 8
CMS DEPTH
% C Sand
% Silt
% Bulk MOISTURE % m .e.% EXCHANGEABLE BASES m.e. % E.S.P. CMS DEPTH
% C Sand
% Silt Clay Density
gm/cnK 1/3Atm. 15 Atm C.E.C, Ca Mg K Na
E.S.P.
0-10 4.00 20 4o 40 0.84 62.4 21.3 24.0 12.80 2.60 1.55 2.15 9.0
10-23 - 18 32 50 0.81 78.5 20.2 20.0 6.8o 1.05 0.60 1.30 6.5
23+ *x 18 30 56 1.23 - 39.2 20.1 18.0 \- 7.6o 0.70 0.25 1.55 8.6
*
CMS DEPTH
pH 1*5 H20 »H 1:5
' KCl EC 1:5 m.mhos/ cm
m.e Hp
». %
Hv AVAILABLE NÜ Mn Na
TRIENTS K
m.e. % Ca Mg
Bio.Te Plus
N
I
st Cunn-$ ail ? S
P ppm
% N
0-10 6.1 5.2 0.05 - - 1.60 1.24 0.70 7.00 3.4c 50 46 113 26 0.38
1C-23 5.9 4.4 0,06 0.50 - 1.12 0.66 0.19 1.60 l.4o - - mm 18 • M
23+ 5.9 4.5 0.06 - mm 1.38 1.80 0.07 2.00 l.4o -
'
16. 1 M
For % organic matter, multiply % C by 1.73
- 22 -
available moisture is also high. Available Ca, K and Prange from deficiency
to moderate levels whereas Mg, Mn and N are moderate. The topsoil pH ranges
between 5»5 and 6.6 whereas the subsoil pH rangesbetween 5 6 and 7,0,
Soil profile NQ.4l represents these soils. Table 10 gives the analytical
data.
Profile description
Observation point No.^l
Valley bottom
Even
Kabete Trachyte/Colluvium/Alluvium.
38 cms.
More than 38 cms.
38 cms.
Swampy
Mainly pyparus
Dark brown (lOYR 3/3) sticky clay with many
distinct';orange mottles. The structure is blocky
and consists of very fine and fine weakly developed
peds which are slightly firm when moist. Few fine
gravel are present. Fine medium and coarse roots
are common. The lower boundary is smooth and
diffuse.
PIT NO.ifl
LOCATION;
SLOPE:
MICRO-RELIEF;
PARENT MATERIAL;
ROOTING DEPTH;
SOIL DEPTH;
WATER TABLE
DRAINAGE;
VEGETATION :
0-10 cms
10-23 cms,
23-38 cms. +
Very dark grey brown (lOYR 3/2) sticky clay with
many prominent strong brown (7.5 YR 5/6) mottles.
The blocky structure consists of weakly developed
fine and medium peds which are slightly firm when
moist. Fine gravel are few. Fine, medium and coarse
roots are common. The lower boundary is smooth and
clear.
Dark brown (7.5 ÏR ^/h) sticky clay with many
prominent yellowish brown (lOYR 5/8) mottles. The
structure which is blocky consists of weakly deve
loped fine and medium peds. Fine and medium gravel
are many. Fine and medium roots are common. Water
table is at 38 cms.
SOIL 9
This occupies excavated and filled areas.
AREA 10; These are areas of open water
k, PEDOLOGICAL FEATURES OF SIGNIFICANCE IN THE FARM
Slope and Soil Erosion
Topography limits land suitability for development in that when it is
broken and steep access by transport and farm machinery is greatly reduced.
Also closely related to slope of land is the susceptibility to erosion.
Consideration of erosion and erosion potential is however rather complex
sïïjce soil physical features particularly texture and structure come into play.
/23
*- 2 3 -
Coarse textured soils and impermeable clay soils may need only a slight
slope to be susceptible to erosion whereas permeable clay soils such as the
ones that predominate in the farm may be worked under considerable slopes«
It is nevertheless considered that soils with slopes exceeding 8 (l fjO
may be unsuitable for normal arable agriculture without the introduction of
sophisticated and often uneconomic terracing.
Since experiments on soil erosion in Kenya are lacking only three
arMtrary slope categories namely slopes less than 8 slopes 8-12° and slopes
more than 12° have been here employed for the classification. The soils with
slopes 8-12° may be handled for tree crops (where soil depth allows) and
timber but soils with slopes more than 12° (soil 5) may perhaps only suit
grazing and timber plantation. The effect of soil erosion on soil
formation and stability may be visualised from the area of soil h which is
shallow with rock outcrops. It would seem that this area was once exposed to
intensive erosion so that soil formation did not very much advance erosion
with the result that the soils are less deep than those found in other parts
of the farm.
Depth of Soil and Stoniness
•tyie presence of stones within 90 cms. of the surface may not only
hinder root development but may also be a draw back in mechanized cultivatn'.oa ,
The presence of gravel sheets within 60 cms of the surface is also regarded
a detrimental feature despite the fact that they are no hinderance to root
penetration. Gravelly soils contain less available moisture and have a
reduced capacity for retaining nutrients as compared with a non-gravelly
soil.
Soil depth may be examined in relation to the requirement of the wide
range of crops that are grown in the country. For the majority of annual
crops, a minimum soil depth of 60 cms which is free of stones is considered
essential but certain crops require soil depths considerably deeper than
the 60 cms. Coffee, tea and certain horticultural crops (e.g. citrus,
bananas etc.) for instance may require at least 120 cms, depth of soil. The
area of soil *f, because of shallowness and rock outcrop, may therefore be
unsuitable for arable agriculture (even tree crops) although it has slopes
less than 12°.
Drainage, Permeability and Available Moisture
Excessive water in a soil automatically involves inadequate aeration,
lowering of temperature and limited root range. Plants generally require
well ventilated soil for best health and growth. If the free movement of
gasses between the soil and the air above it is impeded by excess soil
moisture, poor seed germination may occur and plants may show an immediate
decrease in the rate of growth since the absorption of essential minerals
and water from the soil is reduced. The plant under such a condition is
very susceptible to disease.
Poor drainage which may be periodic or permanent is normally caused by
the presence of an expanding type of clay mineral mainly the montmorillonite
type. It may however also be caused by the occurrence of a sub-surface pan .*./2<f
- 24 -
(which includes olay pan and indurated ironstone) or a high natural water
table which supports a swamp flora if the water table reaches the soil
surface. In the present area the poor drainage of soil 7 is periodic and
seemsto arise from drainage impedence (measured permeability rate 17 mms/
24 hrs) due to the presence of montmorillonite clay which predominates
in this soil. The permanent poor drainage of soil 8 is however due to a
very high natural water table.
The improvement of the drainage of soil 7 may be easily achieved by
installing ditch drains and incorporating gypsum which increases the soil
solution concentration and so guards against the deflocculation of clay. The
action of gypsum is not expected to lead to a permanent improvement since
once the soil is depleted of gypsum, deflocculation sets in again. So the
application of gypsum may have to be continual. The improvement of the poor
drainage of soil 8 may nevertheless prove to be difficult since ditch drains
do not often adequately cope with situations of high water table. The high
water table may perhaps only satisfactorily be lowered by pumpiaing
The drainage of soil 1 to 5 and also soil 6 which has a slightly high
water table, is on the other hand good. A measured permeability rate for
soil 1 was 345 mms per hour which is rapid. The moisture holding capacity
and available moisture for these well drained soils (See table 11 below)
may also appear to be fair considering that the available moisture for -JK:
soil 1 is l6.9 percent in the surface horizon. This markedly contrasts with
that of soil 8 which is 4l.l percent. The presence of gravel in the deep
subsoil of soil 8 has however greatly reduced the moisture holding power
of the soil.
TABLE 11; Moisture retention and moisture availability
Pit No. Depth cm.
Bulft Density gm/cm-5
Water Retained
1/10 1/3 1 atm atm atm
, % weight b
5 10 atm atm
asis
15 atm
Available moisture
%
16 0-16 0.86 45.4 43.4 36.3 - 27.0 26.5 I6.9
(Soil 1) 16-56 1.02 46.5 44.4 37.8 28.8 28.O 27.4 17.0
56+ 1.07 46.6 46.2 41.6 30.6 29.5 29.0 17.2
13 O-26 1.01 40.3 35.2 32.3 28.I 25.O 24.8 10.4
(Soil 2) 26-50 I.08 40.8 36.7 34.3 28.3 26.3 26.1 10.6
50-91 I.O8 41.5 38.1 35.8 27.3 26.3 26.1 12.0
18 0-20 Ü01 46.8 46.8 43.9 27.** 25.7 25.7 21.1
(Soil 7) 20-49 1.23 40.2 39.8 39.3 26.7 26.1 25.2 14.6
49-90 1.17 44.5- 44.3 44.2 32.5 30.1* 28.9 15.4
kl 0-10 0.84 63.8 62.4 52.7 27.9 23.6 21.3 41.1
(Soil 8) 10-23 O.81 81.0 78.5 69.8 25.2 22.3 20.2 58.3
23+ 1.23 40.6 39.2 35.2 24.3 22.8. 20.1 19.1
.../25
- 25 -
Clay Mineralogy
The major clay mineral in soils 1, 2 and 6 is kaolin which appears
to be poorly crystallized as evidenced by the low intensity and broadness
of the peak. The kaolin is possibly a metahalloysite. The removal of iron
by sodium dithionite from these soils improves the peak greatly and also
makes the identification of illite possible. This illite constitutes
about 15 percent of the clay minerals. Apart from kaolin and illite, soil 1
also reveals the presence of traces of a 2:1 type of clay mineral which
seems to respond to solvation treatment with ethylene glycol in that it
expands.
Soil k and 5 predominantly consist of kaolinite with traces of
illidefined illite while soil 3 consists of a kaolin type of clay mineral to
the exclusion of any other clay mineral. The spacing, the intensity, and the
shape of the peak may all appear to suggest the kaolin type of clay is a
metahalloysite. Montraorillonite predominates in soils 7 and 8 but also
present is about 20 to 30 percent kaolin which in theccase of soil 7 seems o
to be a metahalloysite. The montmorillonite expands fronr 15.66 to 17«66 A
following solvation with ethylene glycol.
The differences in clay mineral properties may influence several
soil management aspects namely fertilization, cultivation and drainage.
Kaolin whose crystal lattice is fixed and which has a low adsorption power
may tend to have a low reserve of plant nutrients. Presence of significant
quantities of illite may also impart to the soil the characteristics
of non-response to potassium and ammonium fertilizer dressings since illite
is notorious for fixing potassium and ammonium ions. On the other hand soils
containing much montmorillonite have a high cation exchange capacity and
therefore may hod considerable reserve of plant nutrients. Whereas frequent
light applications of fertilizer may be the requirement for kaolinite and
illite dominated soils such as soils 1 to 6 fewer but larger dressings may
be the requirement for the montmorillonite dominated soils such as soils
7 and 8.
The nature of clay mineral affects cultivation and drainage
through the tendency of the soil to swell and shrink on wetting and drying,
Montmorillonitic soils such as soils 7 and 8 when wetted may close up and
tend to become dense and poorly permeable with a low air capacity. If
ploughed in the moist condition, montmorillonitic soils being sticky and
plastic tend to adhere to machinery and are puddled. If ploughed when dry,
the hard structure is so pulverised that the soils become impermeable,
poorly aerated and tend to form a surface crust after rain. Thus these
soils may only be cultivated within a very narrow range of soil moisture.
Kaolinitic soils on the other hand may be cultivated within a much
wider range of moisture contents and hence may be subjected to a more
flexible management regime. These soils which predominate in the farm may
be more easily worked and cultivation costs may correspondingly be low«
/26
- 26 -
Nutrient availability
Soil test datafmay not provide precise information on the status
of available nutrients in the soil. The data merely give a broad
indication of those nutrients that may likely limit production.
Table 12 provides the range of available nutrients encountered
for each soil unit whereas the data for the individual observation points
are found in the appendix I. It is evident from these data that the status
of available nutrients is very variable over the farm. These range from
deficiencies to fairly high levels by standards at the National Agricultural
Laboratories which are outlined in appendix H . Phosphorus is generally
deficient and response to phosphatic fertilizers may be expected. The
results of the test for Hp (concentration of the permanent charge hydrogen)
on soils with pH less than 5.5 suggest that liming may not be required.
-d - VO O O o O VO ON O O MD O -d" 0 0 VO rA I A o
VO O • . • • • • •' • • • . • H H CO o\ rA I A rH H O -d -
VO IN 1 1 1 1 1 1 1 1 1 1 1 1 I A 0 > o o O O co VO CM O O •4-
0 0 I A VO CM O co CM -d - J - -d - O Kt I A CM oo • . • * • • • • • • 1
co 1 • • I A I A O o H H CM rH O O
1 co o\ O H
CM o O O O VO CM as r-l H K V rA H co - d - O -d" VO r A CM I A
• • • • • • • • • • <N • • rN I A I A O O VO V£> CM H O O I N 0 0 O CM
-d" -d - O Ó O O CM oo CM rA u •H (Ö H I A r A H J - OO I A I A O H -d- co ft
VO . • • • . • • • • • • O
VO I A H O OO -d" CM rH H r-i 0 0 CO O rA . 0
o CM - d - O O O VO O CM H
cd
o> H 0 0 VO CN r A H OO vo -d- p VO I A • • • • • • . • . • o
• « H H H I A f A I A r+ O O J - f (-
Vu vo 1 1 H 1 1 1 1 1 1 1 I A 1 1 VO VO 1 O O O OO VO I A - d - co VO * CM CO f A O vo J - VO VO -d - I A CM CM CM o\ a
• • . • * • • • • • 1 » 0 m o m -d - O O O O H O O O I A rA O H N
•H
I A vo VO o O o VO oo VO VO o H oo . 0 0 I A J - oo VO VO H XI
H I A • • o • • • • • • • m • CM o H I N I A I A o o O I A T3 VO VO 1 t 1 1 1 1 1 1 1 1 S
i 1 VO o O O O O I A H OO CO I A I A O -d- oo VO I A I A 0 0 VO CM o I A -d - H H -d - J - O
• • • • . 1 • • • • 1 ci • • 0) I A LA O O I A o CM <\J O O VO ci O I A CO
O VO O O o CO t N I N I
KN. ON CM o I A o r N I A -d- -d - & CM ! N • • • VO • r A • • • • o • • . H O Q \ . I A • o O O -d- u
10 VO VO 1 1 1 CM 1 I A 1 1 CM 1 1 - p 1 1 O co O t O 1 H I A H VO rH CM Ti G l A o o ON H I A • J - O OO O VO I A 1 H rA -d- ö O • • • • • • • • . • O 1 * • o
• H t A I A H O -d - CM CM CM O O r H I N o CM o U QJ
- P co 3 O VO o O O o r N VO CM a CM vo • CM O CM er. 0 0 I A r A • « •
f N I N • • VO • • • • • • . G 0) • • I A H CM o> VO J - O o ON O -d- o
H t>- f N 1 1 | 1 1 1 1 1 r A H 1 N £> l 1 -d - CM O O o O co CO H I A I N oo • H cd CM t N H I A H CM co I A -d- I A r A 1 I I A I A U
H • • • • • • • •• • • • O H • • O • H cd >
I A VO O O VO rH CM H O O H H O CM Xi • H cd > ft < O CM o CM I A o
O I A O VO O O rH ON VO CO EH <*H CM I N IN . • • I A CM :• • • . O • • • r A CM OO • • H o O •4f II
1 N t N r A 1 r A H - d - -d - 1 1 H 1 1 Q) I 1 I - d - 1 1 1 I 0O CM O CO O H S 60 H CM CM rH O VO -d" t N H O rA CM - d - rA ON o •g • • • • • • • • * • 1 1 • • u •g I A I A O O H O H O o o vo I A O H « +>
CQ
•• - P U CM • H • H H C
fco "SS.
• Eu
a> <ü S •• H H • £ X £ ft <D X I •r i a ft •<& "se. - P cd o te cö w ö o
E H CO ft « O S s f^ S o S
- 27 -
5. S U M M A R Y
Eight soils, based on soil phase, have been delineated on approximate
scale of 1:2,850, The well drained group of soils consists of 3
variants (Soils 1 to 5) arising from variations in depth of soil and
slope of land. The imperfectly drained group however consists of j5
variants (Soils 6 to 8) resulting from conditions of water table and
drainage. Soil 6 has a seasonal high water table whereas soil 8 is a
permanent swamp. Soil 7 however has a impeded drainage because of the
predominance of the expanding type of clay, mineral (montmorillonite).
The soil fertility appears very variable over the farm. Both
conditions of extreme deficiencies and fairly high levels of nutrients are
encountered.
The quality of the waters in the farm seems satisfactory for irrigation.
December. 1970.
D. 0. Michieka
N. N. Nyandat
- 28 -
6. R E F E R E N C E S
Dumbleton, M.J. 196?. Origin and Mineralogy of Africa Red clays and
Kauper Marl. Q.J. Fngng Geol. 1 p 39-^5
Gethin-Jones, G.H. and Scott, R.M. 1958. The Soil map of Kenya Govt.
Printers, Nairobi.
Mehlich, A., Pinkerton, A., Robertson, W. and Kempton, R, 1959. Mass
Analysis methods for soil fertility evaluation.
Cyclostyled paper of the National Agr. Labs. Nairobi.
Munsell Colour Chart, 195^. The Munsell Colour Company, United States.
Saggerson, E.P. Geology of the Nairobi area. Geological report
No.98 In press.
Scott, R.M. 196I The Soils of Nairobi - Machakos - Yatta area. Govt.
Printers, Nairobi.
Sherwood, P.T. 1967. Classification Tests on African Red clays and Keuper
Marl. Q.J. Engng - Geol. 1 p V?-53.
United States Handbook N0.6O, 1951. The Diagnosis of Saline and alkali
soils. U.S. Dept. of Agr.
United States 7th Approximation, 196^. A classification system. U.S.
Dept. of Agr.
United States Handbook No.l8, 1951. The soil Survey Manual. U.S. Dept.
of Agr.
- 29 -
APPENDIX I
Analytical data for auger soil samples
Field designation No.B No.1
~ 1
Lab.No/70 6858 6859 6860 686I 6862 6863 6864
Depth (cm) 0-35 35-80 80+ O-3O 3O-6O 60-100 100+
AVAILABLE NUTRIENTS
pH i:l 6.4 6.9 7.3 6.2 6.4 6.8 4.8 '•
Na m.e.% O.O6 0.10 0.15 0.22 0.14 0.14 O.08
K m.e,% 1.92 1.30 0.18 I.6O I.62 1.12 0.25
Ca m.e.$ 13.40 9.60 7.60 4.80 2.60 I.80 0*40
Mg m.e,% 4.00 1.60 1.40 2.00 0.10 2.20 I.80
Mn m,e.% 0.35 0.42 O.58 O.78 0.64 O.58 O.43
P ppm 23 23 24 18 20 22 12
N % 0.49 - - O.34 - — -
C % 3.37 - - 2.01 - -
Hp m.e.% - - - - - - 1.4
TEXTURE *WD EXCHANGEABLE BASES
Sand % 14 10 10 14 10 10 12
Silt % 24 26 16 20 22 14 4
Clay % 62 64 74 ' 66 68 76 84
Class C c c C C c C
C.E.C. m.e.# 37.2 33.2 28.4 32.0 22.2 23.6 21.2
Ca m.e. % 22.2 17.6 15.2 12.8 12.0 11.6 3.2
Mg m.e.% 4.0 1.0 0.5 1.3 1.9 2.6 0.9
K m,e.# 4.1 3.0 0.5 3.5 3.6 2.5 0.5
Na m.e.# 0.2 . 0*1 0.2;. , 0;2 . 1 •• . '
'0.3 0i3 0.1
C for Class = Clay
_ 30 -!
Field Designation No. 2 ;
No. 3 No.4
Lab.No./70 6865 6866 6867 6860 6809 6870 687I 6872 6873
Depth (cm) O-5O 50-IOO 100+ o-4o 4o-70 70+ 0~40 40-90 90+
AVAILABLE NUTRIENTS
pH 1:1 1
5.7 1
6.1 4.6 5.7 6.2 6.1 6.1 6.5 6.5
Na m.e.% 0.06 0.04 0.04 0.06 0.02 0.08 O.06 Trace 0.02
K m.e.% 1.16 I.30 0.l4 1.04 O.5O 0.16 I.28 1.24 0.91
Ca m,e,% 6.20 I.80 0.40 6.60 2.6O 2.00 5.60 2.00 0.60
Mg. m.e.# 2.40 1.40 1.40 2.60 2.00 I.80 2.00 2.80 3.10
Mn m.e.# O.62 0.52 0.48 0.60 O.5O O.58 0.71 O.62 0.38
P ppm 18 18 14 17 19 17 19 20 20
H % 0.42 - - 0.35 - ,- 0.35 - -
C % 2.58 - - 2.34 - - 2.07 - -
Hp m.e.% - - 2.3 - - - - - -
TEXTURE AND EXCHANGEABLE BASES
Sand % 14 6 8 8 6 8 8 4 2
Silt % 24 10 14 22 10 8 24 18 10
Clay % 62 84 78 70 84 84 68 78 88
Class C c c c C C c" c c
C.E.C.m.e.56 35.0 26.0 21.2 32.O 23.6 23.6 30.0 23.6 20.0
Ca m.e.# 14.4 14.0 3.0 l4.o 12.0 9.6 13.6 11.2 7.2
Mg m.e.# 2.3 2.2 0.6 2.5 1.1 1.7 3.0 2.1 3.8
K m,e.% 2.7 2.9 0.3 2.2 1.1 0.3 3.0 2.9 2.0
Na m.e.# 0.1 0.3 0.2 0.1 0.1 0.1 | 1
0.2 Trace Trace
- 31 -
Field Designation No.5 - No.7 r — -
N0.8
Lab.No./70 68?^ 6875 6876 6880 6881 6882 6883 6884 6885
Depth (cm) 0-40
1
40-90
i
90+ 0-30 30-70 70+ 0-30 30-60 60+
AVAILABLE NUTRIENTS
pH 1:1 5.9 5.8 5.4 5.2 5.2 5.0 5.5 6.0 5.0
Na m,e»% 0.04 Trace Trace 0.08 O.08 0.04 O.O8 Ö.14 O.08
K m.e. % 1.78 0.98 O.54 1.16 0.88 O.98 1.24 l.o4 0.44
Ca m.e.% 6.00 O.80 0.40 3.20 O.80 0.40 6.0 2.20 O.80
Mg m.e.% 3.50 2.6O 3.10 2.00 1.40 0.90 2.60 I.80 1.40
Mn mte.$ 0.59 0.48 0.22 0.66 0.52 0.50 0.82 O.54 0.54
P ppm 16 14 14 14 15 !3 15 16 12
N % O.49 - - 0.35 - - 0.42 - -
C % 3.43 - - 2.52 - - 2.78 «M -
Hp m,e,% - - 0.4o 0.4o 0,50 1.20 0.10 - 1.0
TEXTURE AND EXCHANGEABLE BASES • • I • • • • . . . . - -
Sand % 12 4 6 12 8 6 10 12 8
Silt % 24 12 4 12 14 8 22 12 10
Clay % 64 84 90 76 88 86 68 76 82
Class C C C C C c c c C
C E . C.m. e •% 30.0 22.2 20.0 3O.O 33.2 19.0 3O.O 22.2 19.0
Ca m.e./ö 12.0 6.0 4.0 8.4 5.2 3.2 12.0 9.4 4.4
Mg. m.e,% 3.7 2.4 3.7 1.0 1.0 Trace 2.1 0.6 1.1
K m.e,% 3.7 2.4 1.1 2.5 1.8 2.0 2.8 2.2 0.9
Na m.e.Jé Trace Trace Trace Trace Trace Trace Trace Trace Trace
- 32
Field Designation No.9 NO.10 No.11
Lab.No./70 *
6886 6887 6888 6889 6890 6891 6892 6893 6894
Depth (cm) 0-30 30-80 80+ 0-30 30-70 70+ 0-55 55-90 90+
AVAILABLE NUTRIENTS
pH 1:1 6.1 6.7 6.6 Ï.8 6.2 4.5 6.1 6.9 6.8
Na m.e.% 0.15 0.12 0.24 0.10 0.10 0.08 O.16 0.30 0.14
K m.e.% I.70 1.02 0.54 1.30 0,-98 0.22 1.42 1.12 0.82
Ca m.e.% 9.6O 4.20 2.40 5.40 2.00 0.40 10.00 5.8O 4.00
Mg m.e.% 3.10 2.5O 2.40 3.00 2.00 I.30 3.00 2.3O 2.4o
Mn m.e.% O.58 0.42 0.64 0.62 O.6O O.47 O.58 0.46 O.52
P ppra 20 21 22 19 18 12 23 20 20
N % 0.44 - - 0i35 - - 0.39 - -
C % 2,87 - - 2.52 - - 2.43 - -
Hp m.e.% - - - 2.10 - -
TEXTURE AND EXCHANGEABLE BASES
Sand % 10 6 8 8 8 10 12 10 12
Silt % 26 18 14 24 12 12 26 18 12
Clay % 64 76 78 68 80 78 62 72 76
Class C c c c C C C C C
C.E.C.m.e.^ 36.0 27.2 13.6 28.4 23.6 21.8 33.2 24.0 23.6
Ca m.e.% 19.0 15.8 8.0 12.8 10.4 3.6 I8.4 16.• 15.2
Mg m.e.% 3.3 2.3 1.6 2.7 1.3 0.7 2.1 1.9 1.8
K m.e. % 3.7 2.3 0.6 2.9 2.1 0.4 3.1 2.5 1.8
Na m.e.% 0.2 0.2 0.1
l
0.1 0.1 0.1 0.1 0.2
1 0.1
- 33 -
Field Designation No.12 No.l4 No.15
Lab.No./?0 6895 6896 6897 69OI 6902 6903 690& 6905 6906
Depth (cm) 0-30 3O-6O 60+ O-50 50-90 90+ O-5O 50-90 90+
AVAILABLE NUTRIENTS
pH 1:1 5.9 5.5 4.9 6.0 6.4 6.4 6.8 6.7 6.1
Na m.e.% 0.04 Trace 0.02 0.12 O.06 0.09 O.08 0.06 0.l4
K m.e.% 1.30 0.86 O.25 1.10 O.58 0.18 2.15 1.66 1.34
Ca m.e.% 5.40 1.40 0.40 7.6O 3.00 l.4o 6.00 2.60 6.20
Mg m.e.% 3.0 I.80 I.8O 2.80 2.00 6.60 3.80 3.70 4.20
Mn m.e.% 0.68 0,46 0.33 0.68 0.62 0.62 0.53 O.52 0.76
P ppm 20 19 18 22 25 24 28 24 18
N % O.43 - - O.38 " /
- - 0.37 - -
C % 2.96 - - 2.37 - - 2.22 - -
Hp m.e.% - 0.20 1.20 .- - - - - -
TEXTURE AND EXCHANGEABLE BASES
Sand % 12 4 8 12 8 8 14 10 8
Silt % 20 14 10 24 16 14 12 12 14
Clay % 68 82 82 64 76 78 74 78 78
Class C c c C C C C C C
C.E.C.m.e.% 32.0 2.2 19.0 32.0 19.0 21.2 32.O 22.2 21.2
Cà m.e.% 12.4 6.4 4.0 14.8 11.2 9.6 17.2 12.0 10.8
Mg m.e.% 3.0 0.7 Trace 1.3 Trace 2.1 3.0 2.0 1.8
K m.e.% 3.0 2.1 0.6 2.4 1.2 0.4 4.8 3.3 1.1
Na m.e.% Trace Trace Trace 0.2 0.1 0.2 0.1 0.2 0.2
- 3 4 -
Field Designation No.17 No.l9
Lab.No. 6910 69II 6912 6917 6918 6919 692O
Depth (cm) O-3O 30-70 70+ 0-30 3O-6O 6O-9O 90+
AVAILABLE NUTRIENTS
pH 1:1 5.9 6.5 6.6 6.1 6.5 6i5 6.6
Na m.e.# 0.10 0.09 0.14 0.08 O.06 O.06 0.08
K m.e. % I.38 0.90 0.10 2.15 1.48 0.68 1.21
Ca m,e.% 8*80 6.20 5.00 5.60 3.60 1.4o 2.20
Mg m.e.% 3*7Q 2.30 I.80 3.40 2.90 3.00 2.5O
Mn m.e.% 1.12 0.66 0.58 O.60 0.47 0.32 O.5O
P ppra 24 23 24 24 24 22 23
N % 0.51 - - 0.31 - - -
C % 3.1^ - - 2.81 - - -
Hp m.e.% - - - - - - -
TEXTURE AND EXCHANGEABLE BASES
Sand % 12 14 12 12 8 8 12
Silt % 20 12 12 20 16 24 14
Clay % 68 74 76 68 76 68 74
Class C C C C C C C
C.E.C. m.e. % 32.0 27.2 23.6 35.0 26.0 21.2 23.6
Ca m,e,% 15.4 16.0 15.2 13.2 13.6 9.6 11.6
Mg m.e.% 2.3 0.7 0.7 2.4 1.0 4.4 2.1
K m.e.% 2.9 2.9 0.2 4.8 3.5 1.4 2.9
Na m.e.# 0.1 0.2 0.3' 0.1 0.5 0.1 0.1
- 35 -
Field Designation No. 20 No. 21 No.22
Lab.No./70 6921 6922 6923 6924 6925 6926 6927 6928 6929
Depth (cm) 0-30 30-90 90+ O-3O 3O-6O 60+ o-*4o
>
4o-70 70+
AVAILABLE NUTRIENTS
pH 1:1 6.3 6.6 6.5 6.4 6.8 7.0 6.1 6.6 6.8
Na m.e.% 0.02 0.08 0.02 0.04 0.10 0.20 O.08 0.04 O.06
K m.e.% I.30 o.44 O.26 1.80 0.60 O.16 1.46 O.90 0.46
Ça m.e»% 5.20 2.00 1.00 10.4 8.0 7.20 8.60 4.0 2.0
Mg m.e,% 2.6O 3.00 4.4o 2.90 I.60 1.70 3.60 2.20 3.0
Mn m.e.% 0.59 O.6O O.6O 0.71 O.56 0.68 0.81 O.6O 0.52
P ppm 20 24 16 20 16 17 15 16 17
N % 0.31 - - 0.48 - - O.49 - -
C % 2.52 - - 3.11 - - 3.23 -T
Hp m.e.%
" " " " "
TEXTURE AND EXCHANGEABLE BASES
Sand % 16 6 8 16 12 14 12 8 12
Silt % 16 16 12 24 24 20 24 16 10
Clay % 68 78 80 60 64 66 64 76 78
Class C c c c C c c c c
C.E.C m.e.# 3O.O 21.2 20.0 36.0 30.O 28.4 33.2 24.0 22.2
Ca m.e,% 13.6 10.4 7.6 18.0 16.8 16.4 14.0 11.2 9.2
Mg m.e.% 1.9 1.3 3.0 2.7 0.9 0.6 1.7 Trace 0.8
K m.e.% 3.3 1.1 0.6 3.8 1.2 0.3 3.0 1.0 0.4
Na m.e.% 0.1 o.l 0.1 0.1 0.2 0.3 Trace 0.9 0.5
- 36 s
Field Designation No. 23 No.24 No. 25
Lab.No./70 6930 6931 6932 6933 6934 6935 6936 6937 6938
Depth (cm) 0-35 35-70 70+ 0-30 30-70 70+ 0-30 30-60 60+
AVAILABLE NUTRIENTS
pH 1:1 6.0 6.6 6.4 6.0 6.6 6.3 6.2 6.7 6.6
Na m.e.% 0.06 0.08 Trace 0.06 0.06 0.10 0.12 0.08 0.06
K m.e.% 1.48 1.70 1.38 1.44 1.02 0.38 1.46 0.94 1.10 *
Ca m.e.% 6.60 2.60 1.20 9.80 4.0 1.80 12.8 5.4o 2.80
Mg m.e.% 3.60 2.20 2.0 3.0 2.60 3.0 3.4o 2.10 1.90
Mn m.e.% 0.79 0.6i 0.46 0.82 0.87 0.76 0.66 O.56 O.58
P ppm 15 15 13 18 17 15 20 16 17
N % 0.47 - - 0.47 - - 0.52 - -
C % 3.34 - - 2.95 - 3.30 - -
Hp m.e.% - - - mm - - .- - -
TEXTURE AND EXCHANGEABLE BASES
Sand % 4 4 4 10 10 8 12 8 8
Silt % 28 18 8 18 22 20 28 22 14
Clay % 68 78 88 72 68 72 60 70 78
Class C c C c c c C C C
C.E.C.m.e.# 35.0 20.6 22.2 21.2 26.0 20.0 35.0 24.0 20.0
Ca m.e.% 12.4 8.8 6.8 15.2 12.0 8.4 17.6 13.6 11.2
Mg m.e.% 0.9 Trace Trace 0.8 Trace 1.0 1.1 Trace Trace
K m.e,% 2.9 3.1 2.7 2.9 2.1 0.9 12.9 2.0 2.4
Na m.e.% 0.4 0.5 0.4 0.3 0.5 0.5 0.4 0.4 0.4
- 37 -
Field Designation No. 26 No.27 No. 28
Lab.No./70 6939 6940 694l 6942 6943 6944 1
6943 6946 6947
Depth (cm) 0-35 35-90 90+ 0-40 40-70 70+ O-3O 30-60 60+
AVAILABLE NUTRIENTS
pH "l:i 6.1 6.5 6.5 6.1 6.7 6.7 6.3 6.3 6.5
Na m.e.% O.O8 o.o4 0.04 O.08 o.o4 Trace O.08 0.o4 Trace
K m.e. % I.56 1.16 0.25 1.66 1.20 O.78 I.72 1.70 I.I6
Ca m.e.% 8.0 4.40 2*20 10.2 3,6o 2.40 6.80 3.20 2.40
Mg m,e,% 4.20 2.20 2.6O 5.0 2.40 2.70 2.90 1.70 1.90
Mn m.e.# 0.96 0.66 0.57 O.87 0.70 0.62 0.70 0.62 O.62
P ppm 18 17 16 17 16 19 15 15 15
N % 0.47 - - 0..54 - - O.38 - -
C % 3.30 - «* 3.47 - - 2.57 -, -
Hp m,e,% - • - *• - - - - - -
TEXTURE AND EXCHANGEABLE BASES
Sand % 16 6 6 16 10 6 14 8 4
Silt % 24 24 16 28 18 16 22 18 14
Clay % 60 70 78 56 72 78 64 74 82
Class C C C c c c c c c
C.E.C.ra.e.Sé 37-2 27.2 21.2 37.2 26.0 21.8 30.0 24.0 22.2
Ca m.e..# 14.8 12.0 8.0 16.8 12.0 10.0 10.8 10.4 9.6
Mg m,e.% 2.1 0.3 0.6 2.6 Trace 0.6 0.9 Trace Trace
K m.e,% 3.1 2.3 0.4 3.4 2.5 1.6 3.0 3.2 2.3
Na m.e.# 0.4 0.4 0.3 0.5 0.4 0.3 0.4 0.4 0.4
- 38 -
Field Designation No.29 No.30 No.31
Lab.No./70 6948 6949 6950 6951 6952 6953 6954 6955 6956
Depth (cm) 0-35 35-80 8©+ 0-35 35-70 70+ 0-40 40-90 90+
AVAILABLE NUTRIENTS
pH 1:1 6.2 6.6 6.7 6.0 6.6 6.8 6.0 6.7 6.6
Na mèe.% O.06 0.04 Trace 0.16 0.08 O.08 O.06 0.12 0.16
K m.e.# 2.05 1.66 0.86 1.34 1.-52 0.92 I.50 I.38 0.74
Ca m»e,% 8.6O .5.0 4.4o 8.80 4.20 2.60 9.60 5.6O 4.40
Mg m.e.% 3.40 1.60 1.70 3.80 2.20 2.30 3.80 I.80 I.90
Mn m.e.$ O.76 0.60 0.58 O.78 O.61 0.51 O.80 O.56 0.64
P ppm l6 18 16 . 18 16 18 20 18 27
N % 0.47 - - 0.43 - - 0.49 - -
C % 2.80 - - 3.59 - - 3.77 - -
Hp m.e.% - - - - - - - • - • -
TEXTURE AND EXCHANGEABLE BASES
Sand % l4 8 8 10 8 4 14 6 8
Silt % 24 24 18 24 12 14 24 22 18
Clay % 62 68 74 66 80 82 62 79 74
Class C C c c C C C c C
G.E.C. nue.% 30.0 28.0 24.0 33.2 27.2 24.0 32.0 28.4 24.0
Ca m.e.% 13.6 12.0 12.8 6.8 11.2 10.8 11.2 12.4 12.0
Mg m.e.% 1.4 Trace Trace 0.5 Trace 1.4 0.2 Trace 0.6
K m.e.% 4.0 3.0 1.8 1.5 2.9 1.9 2.7 2.7 1.8
Na m,e.% 0.3 0.4 0.4 0.4 0.4 0.5 0 . 3 0.5 0.7
- 39 -
Field Designation No .32 No.33 No.3^
Lab.Noi/70 6957 6958 6959 696c 6961 6962 6963 6964 6965
Depth (cm) 0-40 40-90 90+
•
0-40
—
40-80 80+ 0-40 40-90 90+
AVAILABLE NUTRIENTS
pH l:i 1 5.6 | 6.2 5.2 6.3 6.5 6.7 6.0 6.7 7.0 j .
Na m.e.% 0.10 0.10 O.08 0.10 0.14 O.16 0.14 0.12 0.15
K m.e.% I.30 1.76 0.4o 1.21 1.30 0.20 1.34 I.30 0.78
Ca m.e.% 7.80 2.0 1.0 10.0 4.20 3.20 8.60 3.8O 3.0
Hg m.e.% 2.80 1.70 2.20 3.4o 1.60 1.70 2.80 2.20 2.60
Mn m.e.% I.05 O.78 0.55 0.72 0.54 0.55 0.75 0.48 0.50
P ppm 26 20 12 21 18 20 16 19 18
N % O.43 - - 0.42 - - 0.37 - -
C % 3.36 - - 2.92 - - 3.18 - -
Hp m.e.% - - 0.8 - - - - - -
TEXTURE AND EXCHANGEABLE BASES
Sand % 16 10 4 4 6 8 12 4 4 ",
Silt % 28 18 18 26 18 14 22 18 14
Clay % % 72 78 70 76 78 66 78 82
Class C C C C C C C c C
C.E.C. m.e.% 33.2 24.0 21.2 36.O 27.2 23.6 28.4 23.6 23.6
Ca m.e.% 11.6 8.0 5.2 14.0 11.2 10.8 10.8 10.4 10.0
Mg m.e.% 0.5 Trace Trace 1.4 Trace Trac< Trace 0.8 0.6
K m.e.% 2.6 3.2 1.0 2.3 2.5 0.4 2.7 2.3 1.6
Na m.e.% 0.5 0.5 0.4 0.4 0.4 0.6 0.4 0.4 0.6
- 40 -
Field Designation No.35 N0.36 No.37
Lab.No./70 6966 6967 6968 7OI8 7019 7020 7021 7022 7023
Depth (cm) 0-4o ^0-70 70+ 0-35 35-90 90+ 0-40 40-100 100+
1 AVAILABLE NUTRIENTS
pH 1:1 5.9 6.5 5.6 6.8 7.1
•
7.1 • '-'• '
5.8 • ' ' —
5.<f h.5
Na m.e.% O.06 0.04 0.02 0.15 0.04 O.06 0.08 0.02 Trace
K m.e.% I.56 • 1.70 I.I6 3.70 3.50 2.60 2.10 O.74 0.66
Ca m.e.% 6.20 2.40 I.6O "8.0 3.40 2.0 8.0 I.6O 0.40
Mg m.e.% 3.40 2.40 I.90 3.0 2.20 2.8O 2.20 I.90 2.20
P ppm 17 4 12 21 20 20 48 10 8
N % 0.40 - - O.36 - - 0.42 -
C % 3.18 - - 3.07 - - 3.71 - -
Hp m.e.% - - - - - - - 0.30 1.0
TEXTURE AND EXCHANGEABLE BASES
Sand % 12 8 4 8 14 10 10 10 6
Silt % 18 12 12 24 14 8 22 8 6
Clay % 70 80 84 68 72 82 .68 82 85
Class C C c c c C c c c
C.E.C. m.e.% 33.2 22.2 21.2 3^.2 23.4 20.0 24.2 21.2 16.8
Ca m.e.% 10.4 8.0 6.0 14.0 10.4 8.8 11.2 5.6 3.2
Mg m.e.% Trace Trace Trace 3.3 2.6 3.5 2.5 1.7 1.3
K m.e.% 2.9 3.0 0.3 5.7 6.6 ^.5 3.7 1.3 1.3
Na m.e.% 0.4 0.4 0.4 0,5 0.3 0.2 0.3 0.2 C.l
- 41 -
Field Designation No.39 No*42 No. 43
Lab.No./70 7027 7028 7029 7033 7034 7035 7036 7037 7039
Depth (cm) O-6O 6O-9O 90+ 0-40 4O-60 60+ 0-35 35-8C 80+
AVAILABLE NUTRIENTS
pH i:l 3.8 6.3 6.2 1 6.0 6.4 6.7 6.2 6.7 6.4
Na m.e.# Trace o.o4 0.02 0.38 O.08 Trace 0.o4 Trace 0.26
K m.e.# O.78 0.72 0.86 1.26 I.30 2.05 1.10 O.96 O.54
Ca m.e,# 6.40 2.20 0.40 13.4 5.20 I.6O 9.20 2.6O I.60
Mg m.e.# 2.6O 3.40 3.80 3.4o 2.80 2.20 3.0 2.0 2.80
Mn m.e.% 0.53 0.4l 0.29 0.82 0.61 0.66 0.61 0.53 O.49
P ppra 11 8 7 26 14 12 12 13 8
N % 0.43 - • - 0.46 - - 0.45 '- -
C% 3.65 - - k h.85 - - 3.56 - -
Hp m.e.# - - - - - - - - -
TEXTURE AND EXCHANGEABLE BASES
Sand % 14 12 8 20 16 14 12 8 10
Silt % 26 16 8 24 22 16 24 14 8
Clay % 60 72 84 56 62 70 64 78 82
Class C C C C C C C C c
C.E.C. m,e.% 3O.6 22.2 16.8 34.2 20.6 16.0 24.0 16.0 15.0
Ca m.e.% 9.6 6.8 2.8 14.8 9.6 6.8 10.8 7.6 6.0
Mg m.e.# 3.4 4.7 4.9 4.2 3.7 2.2 3.3 1.4 2.6
K m.e.# 1.7 1.5 1.6 2.5 2.4 3.7 1.9 1.8 211
Na m,e,% 0.3 0.2 0.2 0.6 0.3 0.3 0.5 0.3 0.2
- 42 -
Field Designation No. 45 No.46 No. 47 ,
Lab.No./70 7042 7043 7044 7045 7046 7047 7048 7049
Depth (cm) 0-40 40-60 6o+ 0-30 30-60 o-4o 40-100 100+
AVAILABLE NUTRIENTS
pH 1:1 6.2 5.9 6.6 5.1 5.1 5.5 5.7 5.0
Na m.e.% 0.10 0.12 0.02 Trace 0.09 0.26 0.06 0.09
K m.e.% 1.23 1.23 0.42 0.57 0.22 0.95 O.56 0.22
Ca m.e.% 9.0 3.60 4.20 0.60 0.40 5.0 2.0 0.40
Mg m.e.% 4.30 2.60 2.10 1.60 1.20 3.20 2.60 3.0
Mn m.e.% 0.52 0.62 0.60 0.72 0.48 0.91 0.52 0.48
P ppm 21.;. 22 22 11 12 18 20 18
N % 0.39 - - 0.32 - 0.43 - -
C %
*
3.45 - - 2.51 - 4.03 -
Hp m.e.% - - - 1.70 3.30 0.20 - 2.10
TE) CTURE A ND EXCH ANGEABLI : BASES
Sand % 16 14 12 14 14 22 12 16
Silt % 24 l4 12 24 18 20 18 14
Clay % 60 72 76 62 68 58 70 70
Class C C C C C c c C
C.E.C, m.e.% 26.0 19.0 16.8 21.2 14.2 26.0 16.8 16.0
Ca m.e.% 8.8 6.0 9.6 2.4 2.0 8.0 5.6 2.0
Mg m.e.# if.8 3.2 2.9 1.6 1.0 3.7 3.6 4.2
K m.e.^ 1.9 1.5 0.8 0.9 0.6 1.9 1.1 0.5
Na m.e.% 0.5 0.5 0.3 0.3 0.4 0.6 0.3 0.5
- 43 -
Field Designation No.48 No.49 No. 50
Lab.No./70 705O 705I ' 7052 7053 7054 7055 7056 7037 7058
Depth (cm) O-25
— — — — —
25-30 30+ O-30 30-90 90+ O-3O 30-70 70+
AVAILABLE NUTRIENTS
pH 1:1 6.4 6.0 5.1 5.9 5.9 4.9 6.0 5.3 4.8
Na m.e.# 0.72 0.72 0.59 0.09. Trace Trace Trace Trace 0.04
K m.e.# O.80 0.64 0.62 1.04 0.70 0.24 1.66 O.54 0.24
Ca m.e.# 5.8 6.60 if.60 11.8 3.8O 0.40 4.40 1.0 0.40
Mg m.e.% 3.0 2.70 2.20 3.70 2.6O 1.40 2.8O 2.20 1.80
Mn m.e.$ 0.71 1.32 I.28 0.60 o.44 0.31 0.48 0.36 0.30
P ppm 25 29 26 25 20 16 17 14 15
N % 0.20 - - 0.56 - - O.34 - -
C % 1.87 - - 4.4i - - 2.95 - -
Hp m.e.#
"
r 1.10 , ,
- 4.50 - 1.10 3.20
TEXTURE AND EXCHANGEABLE BASES
Sand % 15 20 22 20 16 10 18 8 10
Silt % 24 26 24 28 20 20 16 16 10
Clay % 61 54 54 52 64 70 66 76 80
Class C C C c c C c c c
C.E.C.m.e.% 20.0 21.6 29.0 29.0 2Ö.0 I6.O 19.0 K.8 15.0
Ca m.e,% 10.6 11.2 9.2 11.2 7.2 2.0 6.4 3.6 2.0
Mg m.e.$ 3.7 3.2 2.5 5.3 3.1 1.2 3.7 3.1 1.7
K m.e.% 1
1.5 1.3 |
0.9 2.1 1.5 0.6 2.6 1.0 0.5
Na m.e,% 1.4 1.3
1 1.2 0.3 0.2 0.3 0.2 0.3 0.3
- 44 -
Field Designation No. 51 No.52 | 1
No. 5$ 1
Lab.No./70 7059 706O 70.61 .;» 7062 7063 7064 7065 7066 7067
Depth (cm) o-4o 40-90 90+ O-60 60-90 90+ 0-40 40-70 70+
AVAILABLE NUTRIENTS
pH 1:1 6.2 6.3 5.2 6.6 5.0 5.0 5.7 6.1 7.3
Na m,e,% Trace Trace Trac« o*o4 Trace Trace 0.46 1.90 3.50
K m.e,% I.80 I.I8 O.62 1.92 1.14 0.66 0.82 0.48 O.36
Ca m.e»% 5.20 2.6O O.6O 4.60 0.60 0.40 8.80 9.0 8.60
Mg m.e.% 2.6O 2.50 I.8O 3.0 1.80 1.70 3.20 3.50 3.60
Mn m,e.% 0.59 O.50 O.52 0.55 0.4o O.38 0.62 0.06 0.18
P ppm 27 10 6 22 8 14 11 24 27
N % 0.30 - - O.28 - - 0.39 - -
C % 2.6O - * I.96 - - 3.18 - -
Hp m.e,% - - O.60 - 2.20 2.0 - - -
TEXTURE AND EXCHANGEABLE BASES
Sand % 12 10 12 14 14 8 6 16 20
Silt % 24 16 12 20 8 12 54 20 20
Clay % 64 74 76 66 78 80 40 64 60
Class C c c C C C C C C
C.E.C.m.e.# 21.2 17.8 15.C 19.0 15.0 12.2 22.2 5^.0 55.2
Ca m.e.9é 9.2 6.4 3.2 76 24 1.6 9.8 26.4 26.4
Mg m.e.# 2.9 3.2 2.3 3.5 2.3 0.8 4.5 4.0 6.7
K m.e.% 3.6 2.1 0.9 3.1 1.7 0.9 1.5 1.4 1.1
Na m.e.% 0.3 0.2 0.2 0.3 0.2 0.2 0.9 5.0 7.6
- k5 -
Field Designation •••. N o . 5 5 No. 56 ! . No.57 : - . • -
Lab.No./70 7068 7069 7070 7071. 7072 7073 7074 7075 7076
Depth (cm) 0-40 4o-8o 80+ 0-50 50-80 80+ "• 0-35 35-50 5O.+
L _ _ —
AVAILABLE NUTRIENS
pH 1:1 6.1 5 , 5.1 6.2 6.1 5.5 6.0 5-1 5.0
Na m.e.$ O.08 Trace Trace 0.04 Trace Trace Trace Trace Trace
K m.e.# 1.90 0.46 O.54 2.50 O.82 O.80 1.46 0.40 O.38
Ca m,e,% 4.o 2.20 "•O.JfO 4.60 I.60 o.4o 3.60 0.40 o.4o
Mg m.e.% 3.0 3.0 2.0 2.90 2.90 2.80 3.50 I.80 2.10
Mn m.e.% Oi79 0.55 0.48 0.52 0.30 0.20 0.71 O.60 0.40
P ppm 14 16 14 6 5 6 6 4 6
N % 0.43 - - 0.36 - - 0.35 - -
C % 3.04 - - 2.28 - - 2.08 - -
Hp m.e,$ - - 2.6O - - 0.70 - 2.10 3.10
TEXTURE AND EXCHANGEABLE BASES
Sand % 14 12 10 12 6 10 14 10 8
Silt % 24 20 10 10 14 10 24 20 14
Clay % 62 68 80 68 80 80 62 70 78
Class C C C C C C C C C
C.E.C. m.e.% 29.0 24.0 23.4 34.2 24.0 24.0 34.2 24.0 24.0
Ca m.e.% 6.8 7.2 2.8 8.8 6.4 2.8 8.4 3.6 1.6
Mg m.e.% 2.2 3.2 2.1 2.5 3.9 3.5 3.2 1.7 2.1
K m.e.% 3.6 1.2 1.3 4.8 1.7 1.7 12.9 1.3 1.3
Na m.e.% Trace Trace Trace Trace Trace Trace Trace Trace Trace
-»•46--
Field Designation No. 58 No. 59 N0.60
Lab.No./70 7077 7078 7079 7080 7081 7082 7083 7084
Depth (cm) o-4o 4o+ O-50 50-90 90+ . 0-35 35-80 80+
AVAILABLE NUTRIENTS
pH 1:1 6.3 6.8 5.7 5,4 5.0 5.4 4.8 5.0
Na m.e.% 0.26 0.16 Trace 0.04 0.04 Trace Trace Trace
K m.e.% 1.04 I.06 I.60 0.66 0.42 1
1.48 0.14 0.12
Ca m.e.% 8.20 5.60 2.8O 1.0 0.40 2.0 0.40 0.40
Mg m.e.% I.80 3.80 1.90 1.60 1.70 I.80 O.6O 1.0
Mn m.e.% O.65 O.50 0.50 O.43 0.29 0.70 0.48 O.25
P ppm 25 9 6 3 5 6 3 5
N % 0.31 - 0.31 - • - O.34 - -
C % 1.84 - 2;22 - - 2.31 - «at
Hp m.e.% - - - O.60 .1.10 O.50 2.40 2.6O
TEXTURE AND EXCHANGEABLE BASES
Sand % 30 24 12 10 8 12 6 6
Silt % 28 26 18 10 10 16 16 6
Clay % 42 50 70 80 82 72 78 88
Class C C C C C C C C
C.E.C. m.e.% 24.0 26.O 29.O 30.8 21.2 34.2 30.8 23.4
Ca m.e.% 12.4 12.4 . 6.4 4.4 3.0 6.4 2.8 2.8
Mg m.e.% 1.4 3.1 : 1.5 1.7 1.9 1.5 0.9 0.6
K m.e.% 1.8 2.0 2.9 1.3 0.9 3.2 0.7 0.7
Na m.e.% Trace 0.1
1
Trace Trace Trace Trace Trace Trace
•m. 4? -
Field Designation No.62 No. 63 No.65
Lab.No./70 7088 7089 709O 7091 7092 7093 7094 7095 7096
Depth (cm) 0-35 35-70; 70+ 0-40 40-80 80+ O-25 25-90
•
90+
AVAILABLE NUTRIENTS
pH 1:1 6.2 6.6 6.7 6.0 6.6 7.1 6.0 6.0 4.9
Na m.e.%" O.08 Trace Trace 0.04 0.06 0.14 0.04 0.02 Trace
K m.e.%" O.82 0.5^ 0.40 0.10 0.04 O.06 1.26 O.96 0.27
Ca m.e.%" 7.80 3.20 I.60 7.60 7.60 12.60 7.20 2.0 0.40 % m+e-,% 2.50 2.80 4.20 1.70 : 1.40 1.90 3.50 2.60 2.3O
Mn m.e.# 0.48 0.40 0.40 0.48 ' 0.32 0.38 0.62 0.37 O.I5
P ppm 8 12 12 11 14 17 6 6 4
N % 0.35 • - - 0.30 - - 0.46 - -
C %" 2.34 - - 1.91 - - 3.36 ! —
Hp m.e.# - - •<• - - - - I.8O
TEXTURE AND EXCHANGEABLE BASES
Sand % 15 13 11 11 3 13 15 13 9
Silt % 6 12 14 18 20 20 28 16 14
Clay % 79 75 75 71 77 67 57 71 77
Class C c C C C c C C c
C.E.C. m.e.% 36.O 22.2 26.0 29.0 26.0 30.6 : 32.O 26.O 21.2
Ca m.e.$ 12.0 11.2 9.2 12.0 13.6 16.0 1.2 7.6 2.2
Mg m.e,%" 3.3 4.0 6.0 2.0 1.2 1.4 4.0 3.1 2.2
K m.e.# 2.2 0.9 1.2 0.6 0.4 0.4 3.6 2.6 1.0
Na m.e. % Trace Trace Trace Trace Trace Trace Trace Trace Trace
-•- 48 -
Field Designation No.66 No. 67 No.68
Lab.No./?0 ?097 7098 7099 7100 7101 7102 7103 7104 7105
Depth (cm) 0-50 50-90 90+ 0-5Ö 50-90 90+ 0-40 40-10C 100 +
AVAILABLE NUTRIENTS
pH l:l • 5.2 5.8 3^ 5.6 6.0 5.9 6.3 6.2 6.1
Na m.e.# Trace 0.04
1
0.0k 0.04 Trace Trace 0.18 0.10 0.02
K m.e.$ 0,36 0.06 : 0.06 0.48 0.04 0.02 I.08 1.04 O.6O
Ca m.e.# 3.20 3.60 1.0 4.80 2.0 O.6O 10.8 ! 4.4o 2.40
Mg m.e.% 1.70 3.30 3.4o 2.0 . 2.70 3.40 2.60 1.70 2.20
Mn m.e.% 0.72 0.40 0.42 : 0.62 0.40 0.4l 0.42 0.40 0.40
P ppm 3 8 8 5 9 8 14 12 13
N % 0.35 J. - 0.36 - - 0.41 - -
C % 2.40 - - 2.22 - - 3.45 - -
Hp m.e.% 0.80 - 0.4o - - - - - -
TEXTURE AND EXCHANGEABLE BASES
Sand % 9 11 11 . 11 9 7 15 15 9
Silt % 20 12 10 18 12 8 22 14 10
Clay % 71 77 79 71 79 85 65 81 81
Class c c c c c c c c C
C.E.C. m.e.% 30.8 26.O 22.2 32.O 26.0 20.0 36.O 26.O 2.22
Ca m.e,% 6.8 8.4 4.8 8.0 7.6 4.8 12.8 9.2 8.8
Mg m.e,% 1.4 3.2 4.0 1.7 2.9 2.2 1.9 2.5 2.7
K m.e.% 1.2 . 0.5 0.4 1.3 0.3 0.3 2.6 2.4 1.6
Na m.e.% Trace Trace Trace Trace Trace Trace Trace 0.1 Trace
*. 49 -
Field Designation No.Al No.69 No.70 I 1
Lab.No./70 7106 7107 7108 9631 9632 9633 9634 9635 9636
Depth (cm) 0-40 40-70 70+ 0-40 40-60 60+ 0-40 40-90 90+
AVAILABLE NUTRIENTS ;
pH 1:1 6.1 6.2 6.1 . 5.8 5.9 5.8 5.6 6.6 6.7
Na' m.e.% 0.09 0.10 0;20 0.06 . Trace Trace Trace Trace 0.02
K m.e.% 2.15 0.86 O.43 1.80 i.12 O.82 2.0 0.88 0.72
Ca m.e»# 5.80 6.0 3.0 11.2 4.4o I.80 9.6O 5.20 3.0 i
i Mg m.e.% 2.20 2.0 2.70 3.40 3.20
!
3.70 3.30 2.6O 2.6O |
Mn m.ei% 0.86 0.68 0,78 0.92 1.0 0.98 O.94 0.68 0.55 f
t P ppm 14 8 8 10 15 14 12 18 20 !
i
i N % O.45 - 0.60 - - 0.53 - i
1
C % 3.45 - - 4.62 - - 4.77 - - 1 i
Hp m.e.% - - - - - - - -;
-
TEXTURE AND EXCHANGEABLE BASES
Sand % 27 19 19 22 16 14 16 16 12
Silt % 32. 26 24 26 20 18 24 16 12
Clay % 4l 55 57 52 64 68 60 68 76
Class c c C C C C C c C
C.E.C. m.e.% 26.0 41.4 23.4 32.8 24.6 22.0 36.O 23.6 20o6
Ca m.e.% 12.0 10.8 7.6 14.9 12.7 7.9 14.3 14.3 12.0
Mg m.e.% 2.3 2.9 4.3 3.0 2.2 '2.7 3.1 1.8 2.2
K m.e.% 4.0 1.8 1.0 2.7 2.2 1.4 3.1 1.6 1.3
Na m.e.% Trace 0.1 0.1 0.15 0.15 0.10 0.20 0.15 0.15
-50 -
Field Designation No. 71 •
N0.A2 • No.B — — — — — —
Lab.Nb./70 9637 9638 9639 9640 9641 9642 9643 9644 9645
Depth (cm) 0-35 35-80 80+ O-50 50-80 80+ 0-35 35-75 75+
AVAILABLE NUTRIENTS
pH lil 5.6 5.7 k.9 5.9 6.7 6.3 6.0 6.5 6.5
Na m.e.% 0.04 Trace Trace 0.06 0.02 Trace 0.04 O.06 0.04
K m.e.% 1.30 O.6O O.I6 2.60 . 1.68 I.08 '• 1.26 Ö.91 O.72
Ca m.e.% 6.40 2.0 o.ao 10.2 4.40 . 3.0 9.60 7.40. 4.40
Mg m.e.% 3.20 3.20 3.20 3.40 2.20 2.60 2.90 2.80 2.80
Mn m.e.% t.74 0..86 0.72 0.81 O.54 0.59 0.66 0.59 0.51
P ppm 12 14 Ik 21 19 29 15 25 25
W% 0.40 - - 0.5k - O.50 -1
C % 3.31 - ~ 4.35 - 4.35 Jm —
Hp m.e.% - - I.50 - - - - • -
wm
TEXTUHE AND EXCHANGEABLE BASES
Sand % 16 16 12 16 14 10 18 16 12
Silt % 24 16 12 26 12 10 24 18 18
Clay % 60 68 76 58 74 76 58 66 70
Class C C C c C c . c C C
C.E.C. m.e.% 29.4 22.# 17.4 34.6 24.3 22.0 32.8 26.2 22.0
Ca m.e.% 11.5 7.9 3.6 16.6 13.1 11.5 15.5 16.6 13.9
Mg. m.e.% 2.8 2.9 2.4 2.2 1.5 1.7 2.4 1.7 1.7
K m.e.% 2.1 1.2 0.3 *,9 2.8 1.9 2.3 1.9 1.4
Na m.e.% 0.15 0.15 0.10 0.20 0.15 0,10 0.35 0.20 0.15
- 51 -
Field Désignation No.72 No. 73 No. 74
Lab.Noi/70 9646 9647 9648 9649 9650 9651 9652 9653 9654
Depth (cm) 0-35 35*7C fo+ 0-40 40-80 80+ 0-4o 4o-8o 80+
AVAILABLE NUTRIENTS
pH 1:1 5.7 6.4 6.8 6.0 6.7 6.9 5.7 6.4 5.1
Na m.e.% 0.12 0.08 0.04 0.16 0.04 Trace 0.10 0.06 0.10
K m,e,% 0.60 0.70 0.48 1.58 1.10 0.78 1.78 1.30 0.34
Ca m.e.# 10.6 4.0 2.0 8.20 3.0 1.40 8.0 3.20 0.60
Mg m.e.# 3.20 3.10 3.80 3.30 2.80 3.80 2.4o 4.20 3.70
Mn m»e,% 0.74 0.80 0.78 0.92 0.88 0.72 0,79 0.66 0.60
P ppm 22 21 25 25 22 2 6 9 4
N % 0.49 - - 0.42 - - 0.52 - *M
C % 3.34 - — 3.31 - - 4.59 - -
Hp m.e.# - -
- '-' - O.8O
TEXTURE AND.EXCHANGEABLE BASES
Sand % 18 16 14 18 18 12 18 14 12
Silt % 26 20 18 26 18 16 24 18 12
Clay % 56 64 68 56 64 72 58 68 76
Class C C C c c c c c c
C.E.C. m.e.% 31.2 22.0 21.2 31.2 25.4 20.6 35.6 26.2 21.2
Ca m.e.# 17.7 13.3 11.4 16.6 Ï2.1 9.2 15.2 9.6 4.2
Mg. m.e.# 2.7 2.6 3.6 2.6 2.3 3.6 3.8 4.3 3.3
K m.e.% 1.3 1.3 1.2 3.2 2.2 1.6 3.3 2.4 0.6
Na m.e.# 0.20 0.15 0.15 0.28 0.15 0.10 0.25 0.35 3.10
- 52 -
Field Designation No. 75 No.77 No.79
Lab.Nói/70 9655 9656 9657 9658 9659 9660 966I 9662 9663
Depth (cm) 0-30 30-80. 80+ 0-35 35-75 75+ 0-35 35-75 75+
AVAILABLE NUTRIENTS
PH u i 5.7 6.5 6.8 6.0 6.5 6.7 6.0 6.3 • , J
5*9
Na m.e. 0.14 Trace Trace Trace Trace Trace Trace 0.12 0.12
K m.e.% 0.92 0.75 0.78 I.38 O.62 0.14 0.92 0.75 0.50
Ca m.e.% 9.40 4.0 1.40 12.0 7.40 5.40 8.0 2.20 O.80
Mg m.e.% 3.-40 2.90 3.20 2.6O 2.50 2.6O 3.6O 3.20 2.60
Mn m.e.% 0.73 O.80 O.26 0.75 O.80 O.6I O.63 O.78 O.74
P ppm 6 12 Ét 19 20 20 13 34 22
N % 0.46 - - 0.48 - - 0.39 - -
C % 4.29 - - 4.11 - - 3.58 - -
Hp m.e.% - - - - - - - -
TEXTÜRE AND ECHANGEABLE BASES
Sand % 16 14 10 22 18 20 18 12 12
Silt % 24 28 12 20 16 14 24 36 12
Clay % CO 58 78 58 66 66 58 52 76
Class C c C C C C C C C
C.E.C. m.e.% 32.8 22.6 20.0 37.4 26.2 24.0 33.8 24.0 20.6
Ca m.e. % 14.1 10.6 7.5 16.5 14.2 12*7 12.0 8.9 4.5
Mg m.e.% 2.1 3.2 2.2 2.2 1.4 1.8 2.9 3.3 3.6
K m.e.% 1.8 1.5 !«5 2.4 i'3 0.3 1.8 1.5 1.0
Na m.e.% 0.15 .0.15 0.20 0.15 0.15 0.13 ,
0.15 0.15
- 53 -
Field Designation No. 80 No. 8l No. 82
Lab.No./70 9664 9665 9666 9667 9668 9669 967O 9671 9672
Depth (cm) 0-40 40-85 85+ 0-35 35-80 80+
—
0-40 40-80
i
80+
AVAILABLE NUTRIENTS
pH 1:1 5.9 6.4 6.5 6.0 6.5 6.8 6.0 6.1 1 4.9
Na m.e.# 0.22 0.10 0.12 0.20 O.18 0.15 0.14 O.08 0.08
K m.e.56 1.62 1.23 O.82 O.I6 0.10 '0.09 0.92 O.60 0.14
Ca m.e.% s 10.8 4.0 2*0 14.6 13.8 8.60 6.40 1.60 0.20
Mg m.e.# 2.50 2.0 2.5b 2.60 1.90 1.90
1
2.80 2.40 2.10
Mn m.è.% O.82 0.86 Ö.82 Ö.94 O.38 0.42 O.74 0.72 0.52
P ppm 25 24 28 24 31 28 21 19 17
N % O.49 - - 0.51 - - 0.46 - - •
C % 4.12 • - - 4.05 - - 3.73 - -
Hp m»e,%
- • - • - • • -
mm 1
. .
- - * - - - O.6O
r PEXTURE AND EXCHANGEABLE BASES
Sand % 20 28 18 16 18 16 16 12 10
Silt % 30 10 8 24 20 14 22 14 14
Clay % 50 62 74 Co 62 70 62 74 76
Class C c C C C c C C c
C.E.'C ' m.e.^ 34.6 24.6 22.0 '32.6 32.0 28.0 32.0 23.6 17.4
Ca m.è.% 15.1 12.1 9.4 19.0 I8..2 17.1 11.5 6.6 4.0
Mg m.e.# 2.5 2.1 3.8 2.6 1.9 1.3 2.9 2.3 2.8
K m.e.% 3.1 2.5 2.1 0.3 0.2 0.3 1.8 1.2 0.2
Na m.e.%^ 0.15 0.10 0.15 0.35 O.8O 0.15 0.15 0.10 0.10
- 5h -
rHr Field Designation
, , . . • • • • r -
No.83 '-No. 84 No.C
Lab.Np./70 9673 9674 9675 9676 9677 9678 9679 968O 968I
Depth (cm) 0^40 40^90 90+ •;'••£-.•:- -
0-40 40-80 80+ O-3O 30-75 75+
AVAILABLE NUTRIENTS
pH 1:1 5*9 6.5 6.7 . 5.6 ; 5.9 6.1 6.6 7.0 7.2
Na m.e.% 0.15, U
•'••; 0 . i 2 0.10 0.12 0*08 0.10 4.50 1.11 1.22
K m.e.% 0.ÖÖ, , .O.SO. o*4o 1.16 " 0*98 0.66 0.25 0.32 0.20
Ca m.e.% 9*6b 4.20 2.40 4.60 1*20 0.40 8.60 5.0 8.40
Mg m.e.% •2*10 2.6Ö 2.6O 3.0 3.20 3.60 3.io 3.20 3.70
Mn m.e.% 0.66 . O.58 0.46 0.64 0.68 O.52 1*12 O.80 1.20
P ppm 22 28 23 18 22 23 32 30 30
N% 0*42 - *» O.36 - - 0.39 -
C % 3.^9 - - 2.89 - - 3.46 -
Hp m.e.% - - - - - - - - -
TEXTURE AND EXCHANGEABLE BASES
Sand % 20 16 12 18 10 16 24 30 22
Silt %" 22 16 14 24 18 12 26 16 22
Clay % 58 68 74 58 72 72 50 54 56
Class C C C C C C C C C
C.E.C. m.e.% 32.8 25.4 19.0 25.O 20.0 I8.I 28.1 25.0 27. •
Ca m.e.% 13.5 12.5 10.2 9.6 7.7 5.1 15.5 17 .1 16 .9
Mg m.e.% 2.1 2/5 2.6 2.0 3.9 5.6 3.9 3.6 4.9
K m.e.% 1.6 1.5 0.8 2.1 2.0 1.3 0.6 0.6 0.4
Na m.e.%" 0.15 - 0.15 0.15 0.15 0.15 0.15 0.42 0.14 0.17
-, 55 -
Field Designation No. 85 No. 86 N0.87
Lab.No./70 9682 9ë83 9684 9685 9686 9687 9688 9689 9690
Depth (cm) 0-45 45*£c . 90+ 0-40 40-90 90+ 0-50 50-90 90+
AVAILABLE NUTRIENTS
pfl 1:1 5.9 6.5 6.7 6.1 6.7 6.8 6.5 6.5 7.7
Na m.e.% 0.14 0.32 O.06 0.15 O.08 0.06 0.20 0.10 0.12
K m.e.% 0.94 I.16 0.88 I.16 1.0 0.82 I.56 1.16 1.12
Ca m.e.% 7.40 2.80 1.0 13.6 4.60 2.60 17.2 7.60 5.20
Mg m.e.% 2.80 2.60 3.0 .2.50 1.90 2.60 2.6O 1.90 3.0
Mn m.e.% O.82 0.66 0.66 0.74 0.68 O.65 O.58 0.66 0.64
P ppm 20 25 22 28 26 25 40 31 32
N % 0.49 - - O.49 - O.56 - -
C % 4.26 - - 3.55 - - 4.05 - -
Hp m.e.% - -• - - - - - - -
TEXTURE AND EXCHANGEABLE BASES
Sand % 20 20 8 22 18 16 16 14 10
Silt % 24 12 16 34 22 22 28 18 14
Clay % 56 68 76 44 60 62 56 68 76
Class C c c c C C c c c
C.E.C. m.e.% 23.1 17.1 16.0 26.I I8.O I6.I 27.0 18.O 16.0
Ca m.e.% 7.2 10.9 6.2 17.5 13.5 11.2 19.5 16.O 13.9 '
Mg m.e.% 1.7 2.5 4.1 2.5 1.9 3.6 2.0 1.5 2.7
K m.e.% 1.7 1.9 1.8 2.4 2.1 1.7 2.8 2.2 2.2
Na m.e.% 0.10 0.15 0.10 0.15 0.10 0.10 0.40 0.10 0.10
- 56 -
Field Designation No.88 N0.89 No.90
Lab.Noi/70 9691 9692 9693 9694 9695 9696 9697 9698 9699
Depth (cm) 0-40 40-90 90+ 0-40 40-65 65+ 0-35 35-90 90+ v
AVAILABLE NUTRIENTS
pH lil 6.1 6.3 6.9 6.1 6.a 6.2 7.2 7.7 8.0
Na m.e.% 0.15 0.10 O.O8 0.10 0.04 Trace 0*26 0.15 0.06
K m.ei% 0.20 0.08 O.O6 1.23 0.88 0.72 1.04 1.48 1.66
Ca m.e.% 10.4 6.20 5.20 6.8O 2.20 1.40 32.0 18.6 5.\ '
Mg m.e.% 3.20 I.8O I.80 3.0 1.90 2.70 3.60 4.10 5.0
Mn m.e.% O.74 0.55 O.54 0.68 0.44 O.49 O.08 0.50 0.58
P ppm 21 24 24 15 24 14 201 48 25
N % O.47 - - - 0.40 - - O.62 - -
C % 3.25 - - 3.13 - - 4.68 - - •
Hp m.e.% • - • - - - - - - -
TEXTURE AND EXCHANGEABLE BASES
Sand % 12 12 14 16 14 12 18 16 12
Silt % 20 16 20 20 18 14 32 20 i2
Clay % 60 72 66 64 68 7*f 50 64 76
Class C C C C C c c c c
C.E.C. m.e.% 25.0 19.0 19.0 27.0 18.0 17.0 31.0 23.0 18.0
Ca m.e.% 15.5 13.7 13.9 11.0 9.6 7.0 14.0 12.3 6.9
Mg m.e.% 2.7 1.6 1.3 2.8 3.2 3.9 3.9 4.4 3.9
K m.e.% 0.2 0.1 0.1 2.2 1.7 1.4 2.6 2.8 3.0
Na m.e.% 0.15 0.15 0.15 0.10 0.10 0.10 0.25 0.25 0.15
- 57 -
Field Designation No. 91 No.92 No. 93
Lab.No./70 9700 9701 9702 9703 9704 9705 9706 9707 97.08
Depth (cm) 0~40 40-80 80+ 0-4o 40-90 90+ 0-30 30-75 75+ :
AVAILABLE NUTRIENTS
pH 1:1 6.4 6.8 6.9 6.3 6.5 6.8 6.0 6.3 6.3
Na m.e.% 0.10 0.04 0.02 0.10 Trace 0.04 0.12 0.10 o.o8
K m.e.% Ö.78 0.86 0.82 0.64 0.54 o.l4 •1..66 .0.50 0.22
Ca m.è.% 8.8u 3.40 1.60 11.2 4;40 2.20 10.6 7.80 7.20
Mg m.e*% 3.0 2.30 2.80 3.0 2 »60 2.80 3.30 2.40 2.30
Mn m.e.% 0.70 0.52 0.56 0.60 0^48 0..5Ô O.58 0.52 0.50
P ppra 12 16 20 14- 16 16 18 18 22
N % Q 0.4l - - o.ïî - - 0.66 - -
C % 3.13 - - 3.73 - - 5.16 -' -
Hp m.e.% - - - - - - - - -
TEXTURE AND EXCHANGEABLE BASES
Sand % 16 10 8 18 12 16 18 16 14
Silt % 24 14 10 24 16 22 18 20 16
Clay % 60 76 82 58 72 62 64 64 70
Class C C C C C C c C ©
C.E.C. m.e.% 21.1 24.0 23.1 43.2 32.0 33.2 38.4 37.6 27.2
Ca m.e.% 5-9 5.1 3.9 14.4 12.0 11.0 14.4 16.1 12.8
Mg m.e.% 2.2 2.7 3-2 0.8 1.4 1.3 1.5 1.2 1.3
K m.e.% 2.6 3.0 3.2 1.2 1.0 0.3 2.8 1.0 0.4
Na m.e.% 0.15 0.20 0.20 0.25 0.18 0.18 0.25 0.25 0.18
- 58 -
Field Designation No.9*» No. 95 No.96
Lab.No./70 9709 97BO 9711 9712 9713 97l4 9715 9716 9717
Depth (cm) 0.40 40-90 90+ 0-35 35-90 90+ 0-40 40-90 90+
AVAILABLE NUTRIENTS
pH i:i 5.9 6.3 6.5 5.6 5.3 5.0 5.7 6.3 6.5
Na m.e.% 0.06 0.04 Trace 0.02 Trace Trace Oïlfc. 0.JD6 0.02
K m.e.% 1.21 0.82 0.72 0.77 0.08 0.02 1.04 0.88 0.12
Ca m.e.% 7.20 5.60 1.60 4.0 0.40 0.20 6.40 4.0 2.0
Mg m.e.% ,3.30 2.60 2.40 2.60 2.70 1.70 3.0 2.80 2.70
Mn m.e.% 0.58 0.40 0.32 0.60 0*63 0.48 . 0.66 0.52 0.58
P ppm 12 16 12 11 14 13 16 18 19
N % 0.62 - 0.42 - 0.41 • - -
... ; • C % 4.08 - - • 3.31 - - 3.70 - -
Hp m.e.% - - 2.0 2.40 - mm -
TEXTURE AND EXCHANGEABLE BASES
Sand % 16 18 12 14 10 8 18 14 8
Silt % 28 16 10 26 12 16 •
20 16 14
Clay % 56 66 78 60 78 76 62 70 78
Class C C c c c C C C c
C.E.C. m.e.% 34.6 37.6 26.6 27.6 27.2 25.2 30.6 33.2 25.8
Ca m.e.% 11.7 11.0 8.0 8.t 3.8 3.8 11.0 10.8 4.8
Mg m.e.% 1.6 1.5 3.1 2.2 1.1 1.5 3.1 2.8 4.0
K m.e.% 2.3 1.8 1.5 1.4 0.2 o.i 1.9 1.8 0.4
Na m.e.% 0.18 0.18 0.18 0.13 0.13 0.13 0.18 0.18 0.18
- 59 -
Field Designation No. 97 ? No.R
Lab,No./70 9718 9719 5720 9721 9722 9723
Depth (cm) 0-35 35-60 60+ 0-40 40-90 90+
AVAILABLE NUTRIENTS
pH 1:1 5.9 6.1 6.2 5.8 6.4 6.3
Na m.e.# 0.o4 0.04 Trace 0.12 0.04 Trace
K m.e.% 1.08 0.88 0.20 1.17 0.88 O.28
Ca m.e.# 8.0 5.4o I.60 8.80 2.'60 0.40
Mg m.e,% 2.20 1.70 1.90 3.3» 3.3» 4.20
Mn m.e.# 0.60 O.63 O.58 0.70 O.58 0.40
P ppm 13 lf 22 12 16 13
N % 0.47 - - 0.47 - -
C % 3.99 - - 4.47 - -
Hp m.e.# - - - - - -
TEXTURE AND EXCHANGEABLE BASES
Sand % 16 10 12 16 12 10
Silt % 24 14 12 10 14 8
Clay % 60 76 76 74 74 82
Clasa C c C C C c
C.E.C. m.e.# 35.4 35.2 26.6 36.6 28.O 28.0
Ca m.e.% 13.2 11.7 8.0 I3.2 9.6 4.4
Mg m,e,% 2.8 2.3 2.0 2.1 1.7 4.5
K m.e.# 2.1 1.6 0.5 2.2 . 1.8 0.7
Na m.e.% 0.25 0.18 O.I8 0.25 0.18 0.18
- 6t -
'i, A P P E N D . J X II
Abbreviations
Thé abbreviations used in the report are as outlined below:-
Atm Atmosphere
C Organic carbon
Ca Calcium
C.E.C. Cation exchange capacity
CI Chloride
CO^ Carbonate
EC Electrical conductivity
E.S.P. Exchangeable Sodium percentage
HCO* Bicarbonate
Hp Concentration of permanent charge, hydrogen
K Potassium
KCl Potassium chloride
m.e.# Milli equivalent per cent.
m.e./l Milli equivalent per liter
Mg Magnesium
mmhos/cm Milli mhos per centimeter
Mn Manganese
Na Sodium
N Nitrogen
P Phosphorus
pH The negative logarithm of the hydrogen-ion activity in the soil solution.
pp» Parts per million
R.S.C. Residual sodium carbonate
S Sulphur
ß.A.R. Sodium Adsorption ratio
SQ^ Sulphate
Nutrient deficiency standards at the National Agricultural Laboratories
Deficiencies are suspected if the nutrient levels are below the
following values.
Ca: 3.0 m.e.# Mg: 1.0 m.e.% K: 0»k m.e.#
N : kk.S Kg/ha P: 20 ppm Mn: 0.1 m.e.#
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