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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( 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





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:


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


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:


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:


Profile description


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


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;


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:


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 - -


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 .- - - - - -


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.% - - - - - - -


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.%

" " " " "


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 - - .- - -


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 -


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,% - • - *• - - - - - -


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.% - - - - - - - • - • -


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 - - - - - -


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


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.# - - - - - - - - -


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


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 - - -


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


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


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


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 - - - - - -


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.% - - - - - - - -;

-


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.% - - - - - - - - -


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.% - -• - - - - - - -


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.% • - • - - - - - - -


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 -


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.% - - - - - - - - -


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 -


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.# - - - - - -


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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Documents

SOILS OF KIRIMA KIMWE FACULTY OF AGRICULTURE FARM