29 Land resources of central Nigeria Agricultural development possibilities Volume IB The Bauchi Plains
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Land resources of central Nigeria Agricultural development possibilities Volume 1B The Bauchi Plains
ISSN 0305-6554 ISBN 0 902409 81 6
\LVb Land Resources Development Centre
Land resources of central Nigeria Agricultural development possibilities Volume 1B The Bauchi Plains
Land Resources Development Centre Central Nigeria Project Team (ed. I D Hill)
(J G Bennett, A Blair Rains, P N Gosden, W J Howard, A A Hutcheon, W B Kerr, J E Mansfield, L J Rackham, A W Wood)
Land Resource Study 29
Land Resources Development Centre, Ministry of Overseas Development, Tolworth Tower, Surbiton, Surrey, England KT6 7DY 1978
I6I39 LAND RESOURCES DEVELOPMENT CENTRE*
The Land Resources Development Centre of the Ministry of Overseas Development assists developing countries in mapping, investigating and assessing land resources, and makes recommendations on the use of these resources for the development of agriculture, livestock husbandry and forestry; it also gives advice on related subjects to overseas governments and organisations, makes scientific personnel available for appointment abroad and provides lectures and training courses in the basic techniques of resource appraisal and development.
The Centre works in close cooperation with government departments, research institutes, universities and international organisations concerned with land resources assessment and development planning.
*The name of the former Land Resources Division was changed to Land Resources Development Centre in June 1978.
CENTRE DE DEVELOPPEMENT DES RESSOURCES DE LA TERRE*
Le Centre de Developpement des Ressources de la Terre (l'un des organismes scientifiques du Ministère britannique de Developpement Outremer) apporte son aide aux pays en voie de developpement en matiere de cartographie, recherche et evaluation des ressources de la terre et fournit des recümmandations quant a 1'exploitation de ces ressources pour le developpement de 1'agriculture, l'elevage et la sylviculture. Le Centre conseille egalement, dans les domaines annexes, gouvernments et organismes outremer, se charge de trouver du personnel scientifique pour les postes a pourvoir a 1'etranger et organise des conferences et des stages de formation sur les techniques de base relatives a 1'evaluation et la mise en valeur des ressources.
Le Centre travaille en etroite cooperation avec services gouvernementaux, instituts de recherche, universites et organismes internationaux s'occupant d'evaluation des ressources de la terre et dy plans de developpement.
*l,'ancienne Division des Ressources de la Terre (Land Resources Divinion) a ete renommée Centre de Developpement des Ressources de la Terre (Land Resources Development Centreren juin 1978.
IV List of volumes
Title: land resources of central Nigeria: agricultural development possibilities. LRDC Central Nigeria Project Team (Eds. I D Hill and J R D Wall)
Volume 1A The Bauchi Plains, Executive Summary Volume IB The Bauchi Plains
Volume 2A The Jos Plateau, Executive Summary Volume 2B ' The Jos Plateau
Volume 3A The Jemaa Platform, Executive Summary Volume 3B The Jemaa Platform
Volume 4A The Benue Valley, Executive Summary Volume 4B The Benue Valley
Volume 5A The Kaduna Plains, Executive Summary Volume 5B The Kaduna Plains
Volume 6A The Kano Plains, Executive Summary Volume 6B The Kano Plains
Volume 7 An atlas of resource maps.
v NOTICE TO READERS
This published report is derived from a draft issued to the Nigerian Federal and State Authorities in 1977.
Readers concerned primarily with administrative or policy decisions in relation to agricultural development will find a summary of the various types of agricultural development considered and their location in the Bauchi Plains in Volume 1A of this report, together with a precis.
The attention of readers requiring more detailed information is drawn to the section on the use of the report in Part 1 of this volume.
Throughout this report the word "agriculture" has been used in a broad sense to include crop production, range management and forestry.
vi Contents
LIST OF TEXT MAPS viii
LIST OF SEPARATE MAPS ix
ABSTRACT AND KEYWORDS xi
LIST OF LRD REPORTS ON THE BAUCHI PLAINS xiii
PART 1 INTRODUCTION 1 Preface 1 Objectives 2 Methods 2 Fieldwork and team composition 2 Reporting 3 Use of the report 4 Crops considered 6 Administrative units 6 Acknowledgements 6
PART 2 ASPECTS OF THE ENVIRONMENT 7 Location 7 Climate 7 Relief and drainage 10 Geology 10 Landforms 11 Soils 12 Vegetation 14 Present land use - Density of cultivation 16 Distribution of cultivation 18 Present farming systems 18 Rangeland 21 Forestry 24
PART 3 ENVIRONMENTAL FACTORS AND PRESENT LAND USE IN RELATION TO DEVELOPMENT 27 Introduction 27 Climatic factors in relation to crop growth 27 Land systems with four or five crop options 29 Land systems with three crop options 36 Land systems with two crop options 47
vii Page j_,and systems with one crop option 56 Land systems with moderate or severe limitations to arable crops 63 -Land systems unsuitable for arable crops 72
PART 4 AGRICULTURAL DEVELOPMENT POSSIBILITIES 75 Types of development 75 Assessment of areas for agricultural development 75 Integrated agricultural development projects 80 Large mechanised farms 86 Improvement of traditional grazing 89 Establishment of grazing reserves 92' Establishment of cattle ranches and dairy farms 94 Forestry development for production of timber 98 Forestry development for production of firewood and poles 98 Establishment of forest reserves for protection against erosion • • - * 102 Constraints tc development 103 Research needs 106
PART 5 REFERENCES 109
APPENDIXES
APPENDIX 1 INTERPRETATION OF SOIL DATA Al APPENDIX 2 ASSESSMENT OF EROSION HAZARD A17 APPENDIX 3 MINIMUM SIZE OF ECONOMIC FARM UNIT A19 APPENDIX 4 EVALUATION OF THE GROWTH POTENTIAL- OF FOREST RESERVES A21
TEXT MAPS
following page 1.1 Project area 1 1.2A Location of the Bauchi Plains 4 1.2B Administrative boundaries.post-1976 4 1.3 Areas suitable for integrated agricultural development 84 projects 88 1.4 Areas suitable for large.-mechanised farms 90 1.5 Areas suitable for improvement of traditional- grazing viii following page 1.6 Areas suitable for establishment of grazing reserves 94 1.7 Areas suitable for cattle ranches or dairy farms 98 1.8 Forest reserves for production of firewood and poles loo 1.9 Areas requiring reservation or strict conservation 102 l.lOA Isohyet map 8 1.10B Theisson polygon map 8 1.11 Relief 10 1.12 Drainage basins 10 1.13 Physiographic units 12. 1.14 Vegetation 14
SEPARATE MAPS (in separate folder)
1 Land systems - the Bauchi Plains (Sheets a and b)
2 Present land use - the Bauchi Plains (Sheets a and b)
3 Areas with minimum environmental limitations to crop production - the Bauchi Plains (Sheets a and b)
4 Agricultural development possibilities - the Bauchi Plains (Sheets a and b)
MICROFICHES (inside back cover)
HILL I D, ALFORD M, HUTCHEON A A, RACKHAM L J, TULEY P & WOOD A W (1974-75) Interim report on the landforms, soils and vegetation of the Bauchi area. Volume 1, Landforms and soils. Volume 2, Climate and vegetation. Volume 3, The map units. Miscellaneous Report 152.
IX Abstract and keywords
ABSTRACT
The Bauchi Plains area of the LRDC Central Nigeria Project is briefly described in terms of its climate, landform, geology, soils and natural vegetation. Present land use is described in relation to the intensity and distribution of cultivation, present farming systems, cattle production and forestry activities. This information is used to identify areas in which the environmental limitations are at a minimum for the growth of maize, millet, sorghum, groundnuts and cotton. Areas suitable for different types of agricultural development including livestock and forestry have been identified.
Microfiches of reports supplying additional data on the area are appended.
RESUME
La region de Bauchi Plains qui fait partie de I'aire etudiee par le Projet Nigeria da Centre est brièvement décrite en termes de climat, modele, geologie, sols et vegetation naturelle. On décrit l'utilisation de la terre par rapport a l'intensité et la distribution des cultures, les systèmes de cultivation, l'élevage du bétail et la sylviculture. Par moyen de cette information, on distingue les aires ou. les limitations impos&es par le milieu sont minimales en égard de la cultivation du mai's, du millet, du sorgho, des arachides, et du coton. Les aires qui conviennent aux divers types de la mise en valeur agricole, inclus l'elevage de betail et la sylviculture, sont signalés.
Des microfiches fournissent des donnés additionelles sur la region.
DESCRIPTORS FOR COORDINATE INDEXING
Nigeria, Bauchi, climate, landform, soils, present land use, farming systems, livestock, forestry, agricultural development, maize, millet, sorghum, groundnuts, cotton, potatoes.
xi List of LR DC reports on the Bauchi Plains
A full list is given below of the reports on the Bauchi Plains issued by the Land Resources Development Centre. They contain information for the specialist. They are obtainable only with the agreement of the Nigerian Government. Selected specialist reports are reproduced as microfiches inside the rear cover of the present report.
BAWDEN M G & TULEY P (1968) Preliminary observations on land resources and tsetse control in the Bauchi Area. Miscellaneous Report 63.
BAWDEN M G & RACKHAM L J (1969) The physiography of the basement land province: interim report on the land resources of central Nigeria. Miscellaneous Report 75.;
POSNETT N W, REILLY P M & WHITFIELD P (1971) Nigeria. Volumes 1, 2, 3. Land Resource Bibliography 2.
HILL I D, ALFORD M, HUTCHEON A A, RACKHAM L J, TULEY P & WOOD A W (1974-75) Interim report on the landforms, soils and vegetation of the Bauchi area. Volume 1, Landforms and soils. Volume 2, Climate and vegetation. Volume 3, The map units. Miscellaneous Report 152 (microfiches inside back cover).
BLAIR RAINS A (1975) Livestock production in the Central Nigeria Project area. Miscellaneous Report 198.
HOWARD W J (1976) Land resources of central Nigeria. Forestry. Land Resource Report 9.
GOSDEN P N (1978) Land resources of central Nigeria. Farming systems. Land Resource Report 17.
MANSFIELD J E (in preparation) Land resources of central Nigeria. The interpretation of environmental data in terms of limitations to crop growth. Land Resource Report 22.
BLAIR RAINS A (1978) Land resources of central Nigeria. Rangeland and livestock production. Land Resource Report 18.
xiii Parti Part 1 Introduction
PREFACE
In June 1968 the Nigerian Government asked the British Government to investigate the land resources of parts of each of the six northern states of Nigeria. The investigations have been undertaken by the Land Resources Development Centre (then the Land Resources Division) of the British Government's Ministry of Overseas Development.
The project area covers approximately 230 000 km2 (90 000 mi'). Its western and eastern boundaries are marked approximately by 7° and 10° longitude and it extends from south of the Benue Valley northwards to the border with the Niger Republic (see Text Map 1.1).
Pieldwork was completed in 1976, and a draft of this report was distributed to the Nigerian Federal and State authorities in the following year. The results of the surveys and the draft reports for the Bauchi Plains, Jos Plateau, Jema'a Platform and Benue Valley were discussed in detail at a seminar held in Kaduna in February 1978. This seminar was opened by the Hon Mr Zakariya B Gaiya, Commissioner of Agriculture, Kaduna State and was attended by senior officials from Federal and State ministries and by staff members from several universities. Permission was subsequently received to publish this report for international distribution.
The many background and specialist reports on which the recommendations of the study are based are listed on p.xiii. Some are reproduced as microfiches inside the rear cover of this report.
1 OBJECTIVES
The objectives of the project were to investigate and describe the land resources with particular reference to their agricultural development potential. More specifically, at the request of State and Federal authorities, an assessment has been made of the area's suitability for the growth of annual rainfed crops, maize, millet, sorghum, yams, rice, groundnuts and cotton,together with its rangeland and forestry potential. Agricultural development in the more suitable areas has been considered in the context of improving and expanding existing agriculture and establishing new large-scale, capital- intensive schemes.
METHODS
From a study of aerial photographs the area was divided into units with similar landforms. Ground investigations of the soils and vegetation within these units, linked with climatic studies, enabled areas with the same pattern of climate, landform, soil and vegetation to be defined. Such areas are called land systems. These land systems are identified by numbers, are shown in Separate Maps 1-4 which accompany this report and are referred to whenever development possibilities are discussed.
The environmental data for each land system were interpreted in terms of suitability for various crops, grazing and forestry. This information, taken in association with studies of present land use,was used to identify a number of development possibilities. More details of the methods used are contained in the reports listed on page xiii.
FSELDWORK AND TEAM COMPOSITION
Fieldwork started in January 1969 and continued until December 1976. Details of the progress of fieldwork have been given in six monthly progress reports issued by the Land Resources Development Centre.
The project team included agriculturalists, ecologists, a forester, a rangeland specialist, geomorphologists and soil scientists. Details of the team composition and consultancies are given below.
2 TEXT MAP 1,1
LOCATION OF CENTRAL NIGERIA PROJECT
..•• •••. REFUBLIC OF NIGER
(Appro,) 100 200 300
Project Boundary ^^—^^— Report Area Boundary —^—~ International Boundary *•»•»»• State Boundary
D.O.S. 3250 A Prepared by the Directorate of Overseas Surveys 1977 Team
Agriculture J E Mansfield 1973-77 P N Gosden 1974-77 Ecology P Tuley 1969-72 Mrs M Alford 1970-75 R Rose-Innes 1975-77 R M Lawton 1975 Forestry W J Howard 1973-76 Rangeland A Blair Rains 1974-77 CRC Hendy 1975 Geomorphology M G B aw den 1968-73 Mrs J A Jones 1970-73 L J Rackham 1970-77 Soil science I D Hill 1969-76 A A Hutcheon 1969-77 A W Wood 1971-75' J G Bennett 1973-77 W B Kerr 1974-77 J R D Wall 1976-77 Soil erosion R B Jones 1975
Consultant
Agricultural R Moyle 1975 economics
REPORTING
As the project area is so large it has been divided into six major physiographic regions, the Bauchi Plains, the Jos Plateau, the Jema'a Platform, the Benue Valley and the Kaduna and Kano Plains. These physiographic regions are shown on Text Maps 1.2a and 1.2b in relation to state boundaries. Each region has been reported on separately.
The agricultural development possibilities in each region are discussed in separate volumes of this Land Resource Study: the six volumes are listed on page v. An executive summary has been prepared for each volume.
Environmental data collected during the survey for each of the major physiographic regions are contained in a series of reports published by this Division; those relating to the Bauchi Plains are listed on page xiii. The list
3 also includes reports dealing specifically with farming system^ rangeland and forestry for the whole project area.
USE OF THE REPORT
This report will be of use to technical and planning officers concerned with the formulation of plans or responsible for implementation of planning decisions. In it, environmental data have been summarised and an inter pretation of these data as a number of development possibilities presented. The development possibilities have been assessed on environmental criteria: no attempt has been made to rank them in economic terms.
Readers requiring general information about the environment should turn to Part 2. Those requiring more detailed environmental and present land use information in relation to development possibilities are referred to Part 3. Part 4 deals with actual agricultural development possibilities and has, following discussions with Federal and State authorities, been structured so that it can be used in three ways:
1. Selection of areas for a particular type of agricultural development or project
2. Selection of areas for increasing the production of a given crop
3. Selection of the types of agricultural development for particular administrative units.
The report should be used mainly in conjunction with Separate Maps 3 and 4. Separate Maps 1 and 2 give information about the environment and present land use and are included for reference purposes.
1. Selection of areas for a particular type of agricultural development
The various types of development are defined in Part 4 of this report and identified by a number. Given a decision on which type of development is to be followed, the most suitable areas for this type of development can be found by reference to'Part 4. For example,if it has been decided
4 LOCATION OF THE BAUCHI PLAINS TEXT MAP 1.2a 6°15' 7"00' 8°00' 9"00' 10°00' 11°00'
Xo MATSENA
13°00* - 13 00' x J \ B O R W O
12°00' 12 00
llSae- 11 00
10 00 10 00
9 00 9 00
8 00 8 00'
7°00' 7°00'
6°15' 6°15' 7°00' 8°00' 9°00' 10"00' 1 lo00'
Kilometres 20 0 20 40 60 80 100 120 140 Kilometres , L,——I '—^-r i L1—•—, 1 i i-i- 1— 1 Miles 20 20 40 60 80 100 Miles D.O.S. 3250 Ba Prepared by the Directorate of Overseas Surveys 1977 TEXT MAP 1.2b
POST-1 976 ADMINISTRATIVE BOUNDARIES OF THE BAUCHI PLAINS
Report area boundary —•* Scale 1:1.000.000 State boundary Kilometres 10 5 0 10 20 30 Kilometres Local Government Area boundary LGA headquarters Miles 10 5 20 Miles State capital
D.O.S. 3250 Bb Prepared by the Directorate of Overseas Surveys 1977 that a large mechanised farm is to be established somewhere in the Bauchi Plains, reference to Separate Map 4 and to Part 4 (Table 33) shows that such farms could be established in the Darazo Local Government Area in Land Systems 17, 18, 20 & 25.
2. Selection of areas for increasing the production of particular crops
Given a decision that the production of a given crop must be increased, the areas in which the environmental limitations are at a minimum for that crop can be obtained from Part 4 (Table 34) and identified on Separate Map 3. For example, Table 34 shows that there are no or only minor limitations to the growth of maize in Land Systems 9, 17 and 34 which occur mainly in the Dass, Darazo, Ningi and Toro Local Government Areas. Table 5 shows the number of crop options in each of these land systems and more detailed description can be.obtained from Part 3. The geographical location of these land systems is obtained from Separate Map 3.
3. Selection of the types of agricultural development within particular administrative units
The types of development that are possible in particular administrative units are discussed in Part 4 of this report. The administrative areas can be located on Separate Map 4 and numbers and symbols indicate the types of development for which the environmental limitations are at a minimum. For example, if it is decided that some form of development should take place in the Misau Local Government Area, reference to part 4 (Table 33) and to Separate Map 4 shows that the only type of agricultural development thought to be advisable is an improvement of the existing agriculture, possibly within an integrated rural development project. Separate Map 3 shows that there are either no or only minor environmental limitations to the growth of three crops; millet, sorghum and groundnuts. Further information about the area is obtained by reference to Part 3 of the report in the section dealing with areas with three crop options.
The decision as to which type of development should be undertaken or which crops should be grown depends on economic and social factors that are outside the term of reference of this project.
5 The report can also be used to determine the limitations to the growth of particular crops in areas chosen for development. For example, if it is decided that some form of development should take place in the Toro Local Government Area east of Panshanu, reference to Separate Map 3 shows that the area lies within Land System 3 and is considered to have soil limitations to the growth of crops. These limitations can be found by reference to the legend of Separate Map 1 or to the appropriate section of Part 3.
CROPS CONSIDERED
At the request of Federal and State authorities the following crops were considered: maize, millet, sorghum, yams, rainfed rice, groundnuts and cotton. In the Bauchi Plains, climatic factors severely limit the growth of yams, so the area was not assessed in terms of soil limitations to this crop. Rainfed rice is a special case: in this area, water is probably the most important factor in its cultivation and water relationships will be most favourable in floodplain areas. The largest of these areas are shown on the accompanying maps but because of the complex and variable nature of the soils in the floodplain areas, more detailed investigations are necessary before a realistic assessment of their potential for rice can be made.
ADMINISTRATIVE UNITS
The boundaries of the new States announced in January 1976 have been derived from the Federal Surveys 1:500 0O0 map of Nigeria (1976). Data have been referred to Local Government Areas wherever possible. The boundaries of these Local Government Areas have been derived from the best available published maps.
ACKNOWLEDGEMENTS
We wish to thank the staff of the Federal and State Ministries of Agriculture and Natural Resources for assistance during the project. Thanks are also due to the Director and staff of the Institute for Agricultural Research, Ahmadu Bello University, for help and cooperation in all stages of the survey and n the staff of the International Institute for Tropical Agriculture, Ibadan for technical advice. 6 Part 2 Part 2 Aspects of the environment
The information presented here is summarised from the reports listed on page xiii which contains more detailed information and supporting bibliographies
LOCATION
The area referred to here as the Bauchi Plains is shown on Text Map 1.2a. It 0 0 c\ occupies 22 800 km (8 800 mi ), within the area bounded by 8 50' E and 10° 35' E and 9° 30' N and 11° 25' N.
Its boundaries to the west and southwest are the Kano Plains, Rishi Hills and Jos Plateau and to the east the Kerri Kerri Plateau. To the north the boundary is formed by the Ningi Hills and the southern margin of the Northern Plains. In the south the boundary is marked by the edge of the Jos Plateau and the escarpment leading down to the Benue Valiey.
CLIMATE
Full climatological data published by the Nigerian Meteorological Service are available only for Bauchi town but less comprehensive records are kept for other towns in the area.
Rainfall
The rainfall is about 1 OOO mm (40 in) over much of the Bauchi Plains and is markedly seasonal. The rains start in the first half of May and finish at the end of September. Hardly any rain falls during the rest of the year. The distribution of the rainfall (Text Map l.lO) 'is strongly influenced by the presence of the Jos Plateau to the southwest and west of the area. Here the Toro Plains have a mean annual rainfall of 1 270-1 524 mm (50-60 in). Further east, the Jos Plateau casts a marked rain shadow and the 1 016 mm (40 in) isohyet runs north-south throughout much of the area. The eastern margins of the area have a slightly lower rainfall, particularly in the north, with mean annual rainfall of about 850 mm (35 in). Other local variations may be associated with hills and mountains. 7 Kowal and Knabe (1972) have defined areas thought to have similar temperature, rainfall and evapotranspiration regimes. These areas are shown as polygons, known as Thiesson polygons, constructed around synoptic climatic stations in northern Nigeria: the polygons covering the Bauchi Plains are shown on Text Map l.lo A & B and on Separate.Map 3: Variations within the polygons do occur, but as the climatic data needed to quantify these variations are not available, zones of natural vegetation are taken as indicators of conditions that are wetter or drier than the average defined for a given polygon.
For each polygon Kowal and Knabe (1972) have defined a rainy period, which is the number of days between the start and the end of the rains. The length of the rainy period for the polygons in the Bauchi Plains is shown in Table 1. This has been calculated using data grouped into 10-day periods, so the actual length of the rainy period could be up to 10 days shorter than shown. The dates for the start and end of the rains are also shown in Table 1. During the rainy period^crops are unlikely to suffer moisture stress long enough to affect yield significantly, so it can be considered as the safe growing period. However, Benoit (1976) has shown that the starting date of the rainy season may vary and the probabilities of the rainy period starting on the dates shown are only 40, 30 and 50% for Potiskum, Bauchi and Jos. Table 1 also includes the length of the rainy period as calculated by Benoit (1976) . These lengths are also quoted on Text Map l.ioa & o and on Separate Map 3.
TABLE 1 The length of the rainy period, and the date of its start and finish in polygons covering the Bauchi Plains (Kowal and Knabe, 1972;
Rainy period Polygon Length Starting Finishing in days** date* date/
Potiskum 150 June 1-10 Sept 21-30 Bauchi 140 " May 11-20 Oct 1-10 Jos 190 April 11-20 Oct 1-10
*First 10-day period in which rainfall (P) is >1.0 in followed by two lO-day periods in which (P) »0.5 ET (evapotranspiration) /Last lO-day period in which P >0.5 in and P>ET in previous 10-day period.
8 BAUCHI PLAINS TEXT MAP 1.10a
ISOHYET MAP SHOWING MEAN ANNUAL RAINFALL AND LENGTH OF RAINY PERIOD
Length of the rainy period In days
Mean annual rainfall In mm
Source: Agroclimatological Atlas of the Northern 20 Miles States of Nigeria (KOWAL and KNABE 1972)
D.O.S. 3250 Ka Prepared by the Directorate of Overseas Surveys 1977 BAUCHI PLAINS TEXT MAP 1.10b
THIESSON POLYGON MAP SHOWING MEAN ANNUAL AND MONTHLY RAINFALL DISTRIBUTION AT SELECTED SITES (mm) AND LENGTH OF RAINY PERIOD (days)
Scale 1:1.000.000 Kilometres 10 5 0 10 20 30 Kilometres * Length of rainy period Boundary of Bauch! Plain: (growing season) Miles 10 5 20 Miles Source: Agroclimatological Atlas of the Northern States of Nigeria (KOWAL and KNABE 1972) D.O.S. 3250 Kb Prepared by the Directorate of Overseas Surveys 1977 Temperature
The range of daily maximum and minimum temperatures during the rainy period in each of the polygons covering the Bauchi Plains is given in Table 2
TABLE 2 Range of maximum and minimum temperatures during the rainy period in polygons covering the Bauchi Plains
Temperature range Polygon Maximum Minimum
°C °F °C °F Potiskum 29.5-36.2 85.1-97.2 21.1-23.9 70.0-75.0 Bauchi 28.4-34.9 83.1-94.8 19.6-22.8 67.2-73.0 Jos 23.5-30.9 74.3-87.6 16.6^18.5 61.9-65.3
The highest temperatures occur in April and May just before the rainy season when the mean monthly temperature reaches 29.7 C (85.4 F) . o o Mean monthly temperatures drop to 22.2 C (72.0 F) in December.
Global radiation and hours of sunshine
The range of mean daily global radiation and the range in mean actual hours of sunshine during the rainy period are given in Table 3 for the polygons covering the Bauchi Plains. In Bauchi the mean actual sunshine is less than 5 hours -daily only in the last 10-day period in August, whilst in Jos it is less than 5 hours daily during much of July and August.
TABLE 3 Mean daily global radiation and the range in mean actual hours of sunshine during the rainy period for polygons covering the Bauchi Plains
Range Polygon Mean daily global Mean daily actual radiation cal/cm2/day sunshine hours
Potiskum 383 - 513 5.70 - 9.41 Bauchi 349 - 488 4.86-8.88 Jos 301 - 424 3.71 - 7.20
9 RELIEF AND DRAINAGE
The relief of the Bauchi Plains and their surroundings are shewn on Text Map 1.11. Most of the Bauchi Plains lie between 900 m and 430 m (3 OOO ft and 1 400 ft), but the Kwandonkaya and Solli Hills rise to almost 1 430 m (4 700 ft) and the. isolated Zaranda Hill is just over this height. The summits of other scattered inselbergs are lower. The hills bordering the area such as those of the Jos Plateau, the Rishi and Tongola Hills, rise to over 1 200 m (4 OOO ft) and in the north the Ningi Hills rise to 900 m (3 OOO ft).
The drainage of the Bauchi Plains is shown on Text Map 1.12. In the north it
is principally controlled by rivers draining north eastwards to Lake Chadr whilst in the southern part of the area many of the rivers also flow north eastwards.to join the Gongola, which east of the survey area swings south to the Benue. In the extreme south, the headwaters of the Wase River System drain directly to the Benue.
GEOLOGY
The Geological Map of Nigeria (1964) shows the area mainly as undifferentiated Basement Complex, with areas of Cambrian or PreCambrian Older Granites and Jurassic Younger Granites.
Fargher, in an undated report on the Basement Complex of the Toro Sheet 148, has distinguished garnetiferous schists and gneisses, migmatites, granite gneisses and coarse porphyritic granites.
The migmatites and gneisses are heterogeneous and all grade into each other. The gneisses are typically strongly foliated with irregular banding, veins and pegmatites; scattered felspar phenocrysts occur frequently. Where veining is more abundant the gneisses grade into migmatites; where the gneisses are strongly prophyritic they grade into porphyritic granite.
A series of intrusive rocks and associated acid volcanics of Jurassic Age have been intruded into the Basement Complex and are referred to as the Younger Granites. These have been discussed in considerable detail by Jacobson, MacLeod and Black (1958) and by MacLeod, Turner and Wright (1971). For the most part the Younger Granites outcrop on the margins of the area, but the Kwandonkaya Hills and Zaranda Hill form major massifs within the area. A series of Younger Granite dykes form the prominent ridges of the Daggah Allah Hills.
lO BAUCHI PLAINS TEXT MAP 1.11
RELIEF
Scale 1:1.000.000 Contours (V.l. 500ft.) Kilometres 10 5 0 10 20 30 Kilometres ^— Boundary of Bauchi Plaint Miles 10 5 20 Miles
DOS. 3250 L Prepared by the Directorate of Overseas Surveys 1977 BAUCHI PLAINS TEXT MAP 1.12
DRAINAGE BASINS
(TOO" East of Greenwich
Scale 1:1.000.000 Boundary of Chad Basin Kilometres 10 5 0 10 20 30 Kilometres —^^—^_^^_ Other major watershed . L-—H ' .—' h — • ^» - Boundary of Bauchi Plains Miles 10 5 10 20 Miles
D.O.S. 3250 M Prepared by the Directorate of Overseas Surveys 1977 LANDFORMS
The Bauchi Plains have been subdivided by Hill et al, (1974/5) into 15 broad physiographic units such as hills and mountains, dissected areas and plains (see Text Map 1.13) .
Physiographic Unit i. Hills and mountains
This unit includes all the steep-sided rugged hills within the area,, whether they occur as isolated hills, groups of hills or extensive mountain ranges.
Physiographic Units ii-v. Dissected zones
These are complex areas with incised valleys, irregular drainage pattern o and large amounts of rock outcrop. Slopes are usually in excess of 13 but there may be areas with less steep slopes.
Physiographic Units vi-xv. Plains
o These are undulating areas with slopes mainly less than 3 and incised stream lines. The more finely dissected plains, the Marra, Bauchi, Maijuju, Zurfi and Jigawa Plains occur on or close to watershed areas. The Bauchi Plains mark the watershed between the Chad and Benue drainage systems with the Gongola Plains lying to the south and the Zala, Kariya and Basirka Plains falling gently away to the north: the kariya Plains are distinguished by extensive areas of hard lateritic ironpan and the Basirka Plains by remnants of Kerri Kerri Sandstone.
The physiographic units have been subdivided into smaller simpler landform units, each with a uniform pattern of landform. These landform patterns are the basis of the land systems shown on Separate Map 1.
11 SOILS
Soil classification -_
The soils have been grouped into series (Hill e_t a_l, 1974/5) consisting of soils having horizons with similar characteristics and arrangement in the soil profile, and developed from a particular type of parent material (USDA, 1951). The series are defined primarily on morphological characteristics of depth, drainage, nature of the parent material, amount of gravel or other coarse material and texture of the B horizon: chemical characteristics such as salinity are taken into account where necessary. These soil properties, together with the texture of the surface horizon are thought to be significant to crop growth and are further discussed in Appendix 1.
Wherever possible the criteria used to define series conform to those used at higher levels of soil classification by international classification systems, in particular the Legend for the Soil Map of the World (FAO, 1974).
Soil genesis
The predominant soil parent materials are derived from Precambrian granite gneisses and migmatites of the Basement Complex. The rocks have been modified by weathering and are frequently overlain by gravelly material probably eroded from further up slope. In other places,, lateritic ironpan, probably formed in late Tertiary times, and associated concretionary gravels, overlie the in. situ rocks. In the northern part of the Bauchi Plains there are localised deep accumulations of sand thought to be aeolian.
The surface horizons of many of the soils are sandy, which in the northern parts of the area may be due to aeolian sands. Elsewhere, the sandy surface horizons could be explained by biological re-working, in which the coarser fractions of the fine earth brought up from the weathering zone by termites and other soil fauna accumulates at the surface.
Poor drainage may affect any of these parent materials, and due to the marked seasonal rainfall the water table fluctuates. The sandy surface horizons of many of the soils drain rapidly, particularly where underlain by gravelly material. 12 BAUCHI PLAINS TEXT MAP 1.1 3
PHYSIOGRAPHIC UNITS
0"00' East of Greenwich
H.rd.w^-"
Doguwa-
rliSAU, ,. "BASIRICÄ PLAINS/
>J /BASIRKV-^-, / v.' r ^7
Bulo -//" \Nabayij \ DA^^LBurio, Kafin, MadakA USJE^TED, ZON ZALA(TLAIh >7 \£S?^ ö« BAUCHl\\PLAINS jB^HI ^V DMainaX* ƒ„ ^-0— Liman , \ Ma "" -^> v^^KatagLtm y GONGOLA •WiWS-^ PLAINS JDAGUDlV JISSECTED'/ 'ZONE'«if Tafawa Balewa j^jfiYuli 3JIGAWA [f9Mun ?/ PLAINSQDUII ^, BENUE ESCARPS.. DISSECTED ZONES -^Ba I0W 000.000 Hills and mountains Kilometres 10 5 0 10 20 30 Kilometres Boundary of Baucht Plains I '-T-' h _J r—l L, P7Z1 Miles 10 5 0 10 20 Miles Dissected zones D.O.S. 3250 N Prepared by the Directorate of Overseas Surveys 1977 Soil patterns The land systems shown on Separate Map 1 are soil associations in the sense that they are patterns of geographical associations of soils (Taylor and Pohlen, 1962). In most land systems the soil pattern is controlled by topography. Commonly occurring toposequences of soils are described below. 1. On gneisses or migmatites Very shallow gravelly soils frequently associated with rock outcrops occur on interfluve crests and ridges. Mid-slopes are occupied by slightly deeper gravelly soils. On lower slopes in finely dissected areas^ there is usually a narrow band of deeper more poorly drained, sandy clay loam to clay loam soils above a narrow incised stream line. In less dissected areas with a broader drainage network these more poorly drained soils may be more extensive on appreciable floodplains. Similar deep, poorly drained soils often occur in valley heads. 2. Over ironpan Very shallow soils occur on interfluve crests and ridges associated with out crops of ironpan. Midslopes frequently have deeper well drained concretionary soils but imperfectly drained strongly mottled soils with less concretionary material may also occur. The ironpan and associated gravels usually occur on upper and mid slopes in areas with extensive ironpan outcrops. The soils of the lower slopes and in valley heads are similar to those described above at 1.above. 3. Over aeolian sands Deep, well drained sandy soils occur in localised patches around some inselbergs in the northern parts of the area. The inselbergs are surrounded by long gentle slopes with moderately deep, imperfectly drained sandy loam to sandy clay loam soils overlying massive ironpan. Lower slopes and valley heads are again occupied by deeper more poorly drained soils. 13 4. Alluvial soils A complex of alluvial soils of various textures and drainage classes occupies the floodplains. In general the sandier textured soils occur in the narrower floodplains and on levees beside large rivers. Heavy textured soils are associated with back swamps in the broader floodplains. Soil fertility The cation exchange capacity (CEC) of the commonly occurring soils in the Bauchi Plains is mainly less than 10 and is often less than 5. Adetunji (1974) has assessed soils with CEC of less than 8 as requiring long fallow periods to maintain fertility. The pH is usually less than 6.5 and often less than 6.0 so pH is not usually limiting to any of the crops considered* though the lower horizons of some poorly drained soils have a pH of more than seven. There are insufficient data to make generalisations about the levels of available phosphorus, but phosphorus availability can be related to pH. At the pH levels of the most common soils, phosphorus availability should be only a minor or moderate limitation to crop growth. Limitation due to pH, CEC, levels of exchangeable potassium and phosphorus availability are indicated in the legend to Separate Map 3. 0 VEGETATION The vegetation of the Bauchi Plains reflects interactions of climate, soil and, most significantly, disturbance by man. As a result of his activities little of the original savanna woodland remains. The cultivator using fire and axe in the preparation of the land for farming brings about the development of a shrub-tree savanna, and,in areas of more intensive cultivation, the development of an open landscape with scattered mature trees preserved for their.economic value; the term 'parkland' is sometimes applied to this latter type of vegetation. Within the area there are numerous communities which represent transitions in the distribution of species between two major ecological zones namely the Northern Guinea and the Sub-Sudan. Alford and Tuley (1974) have identified six vegetation complexes, (see Text Map 1.14). 14 BAUCHI PLAINS TEXT MAP 1.14 VEGETATION 0*00' East of Greenwich 9*00' East of Greenwich <• / Vegetation boundary t * ' Scale 1:1.000.000 Kilometres 10 5 0 10 20 30 Kilometres • Transitional vegetation boundary — • — Boundary of Baucht Plains Miles 10 5 20 Miles D.O.S. 3250 P Prepared by the Directorate of Overseas Surveys 1977 The Toro Vegetation Complex This occurs in the southwest'of the Bauchi Plains: mean annual rainfall is 1 270-1 524 mm (50-60 in)• Communities of the rocky areas are characterised by the presence of Ensete gilleti, Euphorbia spp., Uapaca togoensis and Monotes kerstingii. Syzygium staudtii affin. rowlandii and Lophira lanceolata are recorded on deeper soils. Syzygium guineensis and Terminalia macroptera are common on heavier soils. The Nabordo Vegetation Complex North and east of the Toro Vegetation Complex the mean annual rainfall drops below 1 270 mm (50 in) and vegetation is of a Northern Guinea type. A strip of Northern Guinea Vegetation also occurs in the south east. Rocky areas carry Afrormosia/Detarium savanna woodland with Anogeissus/Terminalia spp. savanna woodland in pockets of colluvial soil among the rocks. The Anogeissus/ Terminalia spp. savanna woodland degrades to Terminalia shrub savanna when it is cut for farming. Isoberlinia spp./Terminalia spp. shrub savanna characterises shallow soils. Leguminous trees are common. The Miya Vegetation Complex North of the Nabordo Vegetation Complex;Sub-Sudan zone vegetation is found. Here the annual rainfall is 1 OOO mm (40 in) and the vegetation is dominated by combretaceous species. Afzelia africana is common on the rocks. The amount of Acacia hockii increases with decreasing rainfall. Aeolian sand around inselbergs carries Adansonia/Acacia albida parkland vegetation. Anogeissus savanna woodland/tree and shrub savanna - Khaya variant occurs in this complex; the characteristic species are Daniellia oliveri and Terminalia macroptera as well as those mentioned in the type name. Heavy soils widespread in this unit carry Acacia seyal/Anogeissus savanna woodland. The Bauchi Vegetation Complex In the east of the Bauchi Plains where the mean annual rainfall drops below 1 016 mm (40 in), the vegetation approaches a Sudan type. Guiera senegalensis 15 appears in fallows and shrub savanna. Isoberlinia spp. and Afzelia africana are absent. Adansonia digitata, Hyphaene thebaica and Acacia albida appear in the parkland. The Rimi Vegetation Complex In the north of the Bauchi Plains the mean annual rainfall drops below 1 016 mm (40 in) and the area is characterised by typical Sudan zone fallow communities. Guiera senegalensis dominates the regrowth communities. Boswellia dalziellii is conspicuous on the rocks. Heavy soils in this unit carry Acacia Jeyal/ Anogeissus savanna woodlands. The Hill Complex On high mountains a distinct vegetation has been recorded. Dense woodland with lianas and species such as Oxytenanthe ra abys s ini ca, Allophylus africanus indicate the influence of orographic rain. Lying to the east of the Jos Plateau, Zaranda Mountain has been included in this unit although the influence of orographic rain on the vegetation may not be so pronounced. PRESENT LAND USE Density of cultivation The density of cultivation was assessed from 1:40 OOO scale aerial photographs taken in late 1971. Four percentage classes were distinguished, >60, 59-35, 2 2 34-10 and <10. The assessment was made within areas of 5 km (1.95 mi ) which are shown on Separate Map 2. Land lying within a field boundary was considered to be in the current cultivation cycle: no attempt was made to distinguish between land used for crops and short term fallow land. 16 Areas with more than 1^60% cultivation These are areas with little spare land. Population pressure is such that there is considerable land pressure and farmers move out of the area. Nomadic pastoralism is impossible and animal production is usually restricted to stall-fed beasts. The areas are considered unsuitable for the establishment of resettlement,schemes, large mechanical cultivation farming projects or grazing and forest reserves because of problems associated with land tenure, and the displacement of population. Areas with 59-35% cultivation These are areas in which,for the existing farming system,there is a balance between population and available land. Any development in these areas will result either in a change in the farming system or increased pressure on the land, particularly a shortening of the fallow period. Although nomadic pastoralism is not impossible, there, are likely to be severe problems associated with herding and damage to growing crops. Areas with 10-34% cultivation These are areas with either a high proportion of land unsuitable for arable crops or there is unused land. Fallows are longer than in more intensively used areas. They may be areas of new settlement with farmers moving from densely settled areas. Land is available to support the nomadic pastoralists herds, though burning and other malpractices continue to affect adversely the stock carrying capacity. Where there are no soil limitations to crops and slopes are <3%r.mechanised farming schemes could be established. Areas with <10% cultivation These are areas of low population density with little pressure on the land: there is usually ample grazing land .although, because of its present poor; composition, it only provides satisfactory grazing during the wet season. Space is available for resettlement and mechanised farming schemes if other factors are favourable. 17 Distribution of cultivation Separate Map 2 shows areas of intensive cultivation around the town of Misau, to the east of Miya, south of Darazo, around Bauchi and Liman Katagum and to the east of Bauchi. Much of the area around and to the south west of Tafawa Balewa and most of the Toro Plains are also heavily cultivated.' There is a very large area with little cultivation forming a broad west to east band on either side of Kafin Madaki, probably because this area was until recently infested with tsetse fly. There is little cultivation along much of the upper reaches of the Gongola River. Present farming systems ~~"-- Gosden (in press) has described the agriculture in the Bauchi Plains. It is characterised by rain-fed, upland, hand farming, with some draught animals in particular areas. It is subsistence agriculture with a certain amount of cash cropping to provide for essential purchases and taxes. The main crops are sorghum and bulrush millet, usually interplanted with cowpeas. Sorghum is the dominant crop in all parts of the Bauchi Plains except in the north east, around Misau, where short season bulrush millet (gero) is more-important. Two main farming systems have therefore been recognised in the Bauchi Plains, the Sorghum-Millet System and the Millet-Sorghum System, which grade into one another. An approximate boundary between the two systems corresponds to that between the Bauchi and Potiskum climatic polygons shown on Text Map l.io and also to that between the Sub-Sudan and Sudan ecological zones. It also roughly coincides with the southern limit of light textured, sandy soils developed on aeolian deposits. In both farming systems groundnuts are the most frequently grown cash crop, with cotton assuming some importance around Misau, in the south east around Dull and in parts of the Toro Plains. Records of Marketing Board purchases of scheduled crops show that the tonnages involved are small. In no part of the Bauchi Plains are cash crops as important as the food crops. Other crops grown widely, though on a minor scale, include cassava and beniseed. Rice is seldom grown in upland areas but is grown in wetland or swamp conditions, sugar cane, sweet potatoes and yams are grown on lower slopes and on some 18 floodplains where there is more available water. All the crops are grown on ridges, though sweet potatoes and cocoyams are grown on large ridges or wide raised beds. Most of the cattle in the area are nomadic Fulani herds and livestock plays a minor role in these predominantly arable systems. Apart from some work bulls, few cattle are kept by the settled farmers, whose livestock consists of a few goats, sheep and poultry, possibly a donkey for transport and the occasional horse of the more prosperous farmer or trader. Crop residues such as groundnut and cowpea haulms are commonly stored and fed to animals in the compound: the cereal crop residues are grazed by nomadic herds soon after harvesting of the grain has been completed. Agricultural infrastructure The Bauchi State Ministry of Agriculture and Natural Resources provides most of the services for the advice and assistance of the farming community. These services are described briefly below. Data sources The data quoted below are from Ministry of Natural Resources records. Records are incomplete for some administrative areas and some years. Agricultural extension A Provincial Agricultural Officer is based in Bauchi, with Divisional Agricultural Officers in Bauchi, Katagum and Gombe. There is an Agricultural Superintendent in charge of each Local Government Area which supervises the work of field extension workers. The distribution of these workers, the total number of farming families and the number of farming families per worker in each of the Local Government Areas covered by this report is given in Table 4. 19 TABLE 4 The distribution of agricultural extension workers, the numbers of farming families and the number of farming families per worker by area* within the Bauchi Plains No. of extension No. of farm families/ Development workers No. of farm worker Area* families Agric. Supt. Field Total Field Total Bauchi 5 9 14 Toro 1 3 4 31 936 10 645 7 984 Darazo 3 7 10 36 725 5 246 3 672 Ningi 1 3 4 9 535 3 178 2 384 Dass 1 3 4 6 555 2 185 1 639 Alkalere 1 6 7 29 688 4 948 4 241 Misau 1 4 5 34 166 8 542 6 833 Number of farming families is calculated from 1963 census figures updated by an estimated increase of 2.5% per annum and divided by 7. *Pre-1976 administrative units are used in this table. These figures show that the extension coverage is extremely low. Taken in conjunction with the poor communications of much of the area,it means that very few of the farmers have any contact with advisory services. This must be a major constraint to any improvement in the agriculture of the area. Agricultural centres There are Farm Centres for seed multiplication and experimental work in Bauchi/ Alkalere and near Misau; the latter is associated with a Farm Institute for training farmers,sons. There are Farm Training Centres for the training of Agricultural Instructors in Bauchi and Darazo and a School of Agriculture under construction in Bauchi. Fertiliser Fertiliser is sold through the extension services at sub sidised prices. The total sales of all types of fertiliser range from 371 tons in 1969/70 to 1 513 tons in 1972/3. This represents approximately 10 kg per farming family. Availability of fertiliser is a major constraint to increased production. 20 Agricultural chemicals These are mainly seed dressings and cotton spray. They are sold through commercial outlets so there are no comprehensive records of the amounts used. Demand is greatly in excess of supply. Improved seed and planting material No records of the amounts of improved seed distributed are available, but the total amount is very small. Mechanical cultivation The Ministry of Agriculture and Natural Resources provides tractors for hire at subsidised rates. Operations are restricted to ploughing, ridging and harrowing. A tractor hire unit consisting of two or three tractors is based in each Local Government Area. In mid-1975 there were 31 tractors in the Bauchi Division and two in Misau, of which only two thirds were serviceable. A total of 2 142 ha (5 292 ac) had been cultivated in Bauchi with 12 serviceable tractors, an average of 178 ha/tractor (441 ac/ tractor). In Misau 244 acres were cultivated with two tractors representing only 49 ha/tractor (122 ac/tractor). These figures indicate that the tractors, which represent a considerable capital investment, are not fully utilised. Rangeland Rangeland and cattle production in the Bauchi Plains have been described by ^\ Blair Rains (1975 and in press). The main factors to be considered in the assessment of the potential of an area for livestock production are the natural vegetation and the ways in which man has modified it. Thus, it depends not only on the palatability and nutritive value of grasses and browse and the balance between herbaceous and woody vegetation, but also on the amount of cultivation, the availability of crop residues, the amount of grass that is burnt, the time of year it is burnt and the number of cattle that are in an area. It is very important to recognise that the carrying capacity of an area is very different in the wet and dry season, and it is the dry season carrying capacity that defines the ability of this area to support cattle throughout the year. J 21 Fodder resources Grassland The vegetation of the Bauchi Plains has been described in an earlier section of this report. Blair Rains (1975) has considered its carrying capacity and has assessed the palatability and nutritive value of most of the upland grasses as satisfactory in the wet season. However, during the dry season species such as Schoenefeldia gracilis, Schizachyrium exile, Aristida spp. Eragrostis tremula and Pennisetum pedicellatum occurring in the northern part of the area are nutritively poor. In the south, taller, species such as Hyparrhenia spp. and Andropogon pseudapricus become straw like in the dry season and have little, if any, feeding value. The flood- plain grasslands are particularly important for dry season grazing with species such as Hyparrhenia rufa, Paspalum scrobiculatum and Echinochloa spp. The cultivation of the floodplain is increasing and so reducing the grazing area available; farms sometimes prevent access to uncultivated areas. Fodder trees The woody vegetation also provides fodder. Trees such as Khaya senegalensis, Afzelia africana, Acacia albida and Daniellia oliveri are lopped, particularly during the dry season. Excessive lopping of these trees is taking place which is likely to lead to their elimination. Crop residues Reference to Separate Map 2 shows the distribution of cultivation within the Bauchi Plains. The farmed areas produce large quantities of crop residues that are suitable for animal feeding. The most valuable are groundnut haulms (harawa) and cowpea vines and these are collected by the farmer for his own stock or for sale. The cereal stover is less valuable but is eagerly sought as soon as the heads have been harvested. Cattle population Figures for cattle population must be regarded as only a guide because they are based on tax returns and vaccination programmes. Available figures indicate a total population of almost a quarter of a million cattle in 1971/2. Most of these cattle belong to nomadic Fulani and early in the dry season 22 there is a migration of cattle from the Bauchi Plains, their wet season "home" area, to Nassarawa, Keffi and Abuja their dry season grazing area: at the beginning of the rains this movement is reversed. This seasonal migration does not leave the Bauchi Plains free of cattle for there is an influx of cattle from the north and north east. Thus the problems of supporting this large cattle population are regional problems and cannot be considered for the Bauchi Plains in isolation. Burning Nomadic pastoralists burn perennial grassland to remove old straw-like material and stimulate new growth for stock to graze. This has led to a loss of vigour in the perennial grasses, and valuable species such as Andropogon gayanus, A. schirensis, Beckeropsis uniseta and Schizachyrium sanguineum are increasingly rare. The burning of annual species such as Eragrostis tremula, Schizachyrium exile and Pennisetum pedicellatum also results in the loss of fodder and sometimes of seed. Tsetse Although the Bauchi Plains was formerly infested with tsetse the current eradication programme has controlled the fly over a large part of the area. However, the Lame/Burra Game Reserve in the west and the Yankari Game Reserve to the east of the area could provide reservoirs for reinfestation. Carrying capacity Bearing in mind the factors discussed above, a tentative estimate of the wet-season carrying capacity of unfarmed land is 2-3.5 ha (5-8.6 ac) per adult equivalent. In the dry season crop residues from 1.5 ha (3.7 ac) of cultivated land or 0.5 ha (1.2 ac) of floodplain grazing are sufficient for one adult equivalent. The carrying capacity may be reduced if some of the malpractices are not eliminated. The less disturbed areas of the south have a higher wet-season carrying capacity than those of the north; the carrying capacity of both may be affected by shrub and tree growth; the southern areas can be quickly degraded by dry season fire. 23 Although the successful eradication of tsetse is making more areas available for grazing, the grass cover of many of these areas will also deteriorate unless the worst malpractices are controlled. Forestry I Forest reserves In Bauchi State, forest reserves shown on Separate Map 2 cover 2 2 an area of 1 650 km (637 mi ). The reserves vary in size from 275 km2 (106 mi2) to 5 km (2 mi ). South of Bauchi town there are no ! reserves in the south-east part of the area. The Lame Forest Reserve has recently been increased in area and made into the Lame-Burra Forest and Game 2 2 Reserve covering an area of 2 132 km (823 mi ). V Forest plantations Because the area has a relatively low population there is an ample supply of firewood and poles from the natural vegetation. As a result plantation forestry has been confined to trial plantations covering a few hectares. These have been discussed by Howard (1976). The oldest plantation is near Bauchi itself where Borassus aethiopum and Acacia polyacantha were planted in the 1930's on poorly drained alluvial soils. The Acacia trees now have a height of 11 m and a diameter of 28 cm. Eucalypts have been tried in Magama, Ran, Fobur, Ningi and Zarazong Forest Reserves. Eucalyptus camaldulensis planted on shallow soils in the Magama Forest Reserve is growing 3 slowly providing a mean annual increment of between 3 and 6 m /ha/a. The plantation in the Ran Forest Reserve north of Bauchi has very poor growth and a high proportion of deaths on heavy soil over rock. Neem has been grown at Ningi, Dan Fisa, Gumza and Hardawa. These plantations are at the southern 3 limit of neem's range; it yields between 2 and 4 m /ha/a on the sandy or sandy clay loam soils. Where the soil is shallow (ironpan at 70 cm) the yield is 1 m /ha/a. Two young plantations of Acacia Senegal were planted in 1972. One at Darazo on a freely-drained sandy soil has grown to a height of 2 m whereas the other at Maladumba has a height growth of only 1 m. The trees yield more gum arabic when they are under stress, which may mean that the 24 Darazo plantation grows very fast but does not yield much gum. The total area of plantations is 253 ha established between 1961 and the present time. 3 These figures show that the increments are less than 5 m /ha/a so production forestry in the Bauchi Plains is unlikely to be economic. 25 I Part 3 Part 3 Environmental factors and present land use in relation to development j INTRODUCTION In this part of the report are presented the facts about the environment and present land use from which the development possibilities given in Part 4 have been identified. The basic unit of description is the land system, but for convenience these have been grouped according to the number of crop options, that is to say the number of crops for which there are few environmental limitations: the assessment of environmental factors in terms of limitation to particular crops is explained in Appendix 1. The crops considered are maize, millet, sorghum, groundnuts and cotton. Land systems grouped according to the number of crop options reflect the versatility of the land. The groups are shown on Separate Map 3, also in Table 5, and are described in the following sections. As the groups have limitations in common due to climate, these are discussed for the Bauchi Plains as a whole. TABLE 5 Land systems grouped according to the number of crop options Number of crop options Administrative Moderate or severe Unsuitable for unit 4/5 3 crops 2 crops 1 crop limitations to annual rainfed crops crops considered crops Bauchi State Misau LS20,22, LS2 25,26 Shira LS20,22 LS 19 LS 2 Darazo LS17 LS8,1O, LS7,14,15,19, LSI,2,13 18,20,25 Ningi LS9 LS15,16,21 LSI,2,11,13 Toro LS9, LS4,8, LS27 LS3,6,7,12,14,15, LSI,2,11,13 34,36 16,21,33 Bauchi LS9 LS8,10, LS27 LS28 LSI,2,13,32 LS7,14,15 25 > Alkalere LS9 LS8,lo, LS28,30 LS2,13,32 25 LS27 LS12 Tafawa LS 9 Balawa LS8,10, LS28,29 LS1,2,13,32 31,34, LS27 30 LS3, 12,14 35,36 Dass LS9 LS8,10, LS28,30 LSI,13 34 LS2 7 LS12,14,33 Kano State Birnin LS8, 18, Kudu 20,25 LS19 LSI,2,13 27 TABLE 5 (Continued) Number of crop options Administrative 4/5 Moderate or severe Unsuitable for units 3 crops 2 crops 1 crop limitations to annual rainfed crops crops considered crops Plateau State Jos LS4,8, LS3,33 LSI,2,13 34,35, 36 Barakin Ladi LS3 LS2 Bassa LS4 LS3 LSI,2 Mangu LS8,35,- LS3 LS2,13 36 Pankshin LSIO LS29 LS3,14 LSI,2 Kanara LS 9 LS8,10, LS2 7 LS28,30 LS3,12, 14 LSI,2,13,32 Langtang 31,34 LS3 All areas LS9,17 LS4,8, LS27 LS28,29, LS3,6,7,12,14,15, LS1,2,11,13,32 10,18, 30 16,19,21,23 20,22, 25,26, 31,34, 35,36 CLIMATIC FACTORS IN RELATION TO CROP GROWTH The climatic factors of major importance are the length of the rainy period, maximum and minimum temperatures, global radiation and the number of hours of sunshine during the growing season. These factors which have been described in Part 2 and are considered in terms of their effect on the production of maize, millet, sorghum, groundnuts, cotton, rice and yams. Over most of the Bauchi Plains the length of the rainy period is 150 days and all the crops except yams have a growing period of less than 120 days. Yams require a growing season of at least 180 -days so the rainy period imposes a severe limitation to the growth of yams. As the rainfall is less than 1 300 mm (51.5 in), rainfed rice is likely to suffer periods of moisture stress. Its cultivation is therefore not considered for the Bauchi Plains. However in floodplain areas where water relations are particularly favourable both rice and yams can be grown. There are no temperature limitations to the growth of any of the crops- Kowal and Knabe (1972) give a range of 15-17.8 C (59-64 F) as o o minimum temperatures and 43.9-50 C (111-112 F) as maximum temperatures that the crops will tolerate. Global radiation and sunshine hours indicate the light energy available over the rainy period and although there is a gradual decrease from north east to south west across the Bauchi Plains, there is no limitation to the growth of crops. 28 LAND SYSTEMS WITH FOUR OR FIVE CROP OPTIONS This land occurs mainly in the Darazo, Toro, and Tafawa Baiewa Local Government Areas. It is made ,up of Land Systems 9 and 17. Land System 17 2 2 occurs mainly around Miya and occupies 325 km (125 mi ), whilst Land System 9 2 2 occurs as a number of small isolated areas totalling 103 km (40 mi ). The main characteristics are summarised in Table 6 and discussed below. Limitations to crop growth 1. Soil physical characteristics The physical soil limitations to the growth of certain crops are given in Table 7. This shows that there are no or only minor limitations to the growth of all the crops considered, with the exception of cotton: the predominant soils of 50-100 cm depth, with sandy surface horizons in Land System 17 present moderate limitations to this crop. 2. Soil chemical characteristics The soil chemical characteristics for which data are available are given in Table 8 and assessed as limitations to the growth of the crops considered. 29 TABLE 6 Summary of main characteristics of areas with four or five crop options Land Present cropping Rangeland Crop . Density of Draught Erosion Communica Extension system Occurrence and cattle Forestry options cultivation animals hazard tions coverage no. Food Cash production Maize Darazo and Mainly Sorghum Ground A few Slight Good. Main Field . Rangeland •N o forest Millet Btrnin sparse Fadama nuts in use road extension degraded reserves; Sorghum Kudu though veget Cotton crosses worker due to firewood Groundnut Local pocket of ables the land based in intensive and poles 17 Government intensive system Miya use as extracted Areas cultivation wet and from occurs dry season natural around grazing vegeta Miya tion Maize Bauchi, Mainly Sorghum Variable None Slight Variable Variable Slight No forest Millet Ningi,t moderate Millet reserves; Sorghum Toro, to firewood Groundnut Kanam, intensive and poles 9 Cotton Tafawa extracted Balewa, from Dass, natural Alkalere vegeta Local tion Government Area* TABLE 7 Soil physical limitations to the growth of certain crops in areas with four or five crop options: crop options are indicated by shading % Soil limitation category (SLC) by crop in each land system with nature of Land system limitation* Area to Maize Millet Sorghum Groundnuts Cotton Total area which SLC data refer- Nature Nature Nature Nature Nature No, SLC of SLC of SLC of SLC of SLC of limita limi ta- limita limita limita km mi km mi tion tion tion tion tion 17 325 125 283 109 *60 1 >60 Nil ; 2 >60 Nil >>60 S>tc iiinnncani one][OJi*i- i'otr*'I'IWW'I • 'iKninca» F 1 30-59 Nil 2 >60 tc 1 30-59 Nil >60 tc 1 30- 50- Nil 103 40 88 34 2 10-29 c 2 30-50 c 2 30-59 c 3 10-29 wt limitations Depth Drainage Texture Coarse material D Severe W Severe No severe limitation C_ Severe D Moderate W Moderate Ta Moderate (cotton only) C Moderate d Minor w Minor t Minor c Minor TABLE 8 Dominant soil chemical characteristics assessed as limitations to crop growth for land systems with four or five crop options (based on top 50 cm of soil profile) Limitations due to pH for Land CEC* Exch. K** P pH system meq % availability meq % Maize Millet Sorghum Groundnuts Cotton 9 7.7-9.8 0.3-0.4 5.2-5.4 Min Nil Min Min Nil Mod 17 4.6-9.1 0.16-0.18 5.3 Min Nil Min Min Nil Mod *CEC meq %: >8 Suitable for intensive agriculture; 2.0-7.9 Requires a high ratio of fallow to crops, <2.0 Unsuitable for intensive agriculture (Adetunji, 1974) **K meq % for soils of pH>4.5:>0.10 Adequate; <0.10 Deficient /P availability related to pH: pH Limitations 6.5-7.5 Nil 6 49 6-°-7.51-8.0- )! Minor I'.ts.l] Moderate <5.0 Severe Limitations to mechanical cultivation The predominant slopes in these areas are given in Table 9 together with the range of slopes found on the major facets of each land system. TABLE 9 Dominant slope and range of slopes on major facets in areas with four or five crop options Slopes of major facet Land system Percent Degrees no. Dominant Range Dominant Range 17 0.9% 0-1.7% 0-1° 9 0.9% 0-1.7% 0-1° This shows that both land systems have slopes of mainly less than 1%, and should not require protection works other than contour ploughing and grass strips. However, Land System 9 only occurs in small areas and thus, cannot be considered very useful for large scale mechanised cultivation. Density and distribution of cultivation Reference to Table lO and Separate Map 2 shows that areas of intensive cultivation are concentrated in Land System 17 and throughout most of Land System 9. More than halfof Land System 17 is only sparsely cultivated, mainly lying to the west of Miya. 33 TABLE 10 Density of cultivation in areas with four or five crop options 2 Areas (km ) occupied by density of % of <10% Land Total area Local cultivation (percentage) class density class in Government . system Area forest , 2 .2 >60% 59-35% 34-10% <10% reserve km mi 9 103 40 Bauchi, 2 Ningi 6 100 Tor o 12 5 26 74 Kanam 2 i Tafawa Balewa 5 18 16 4 Dass 2 1 Alkalere 1 1 17 325 125 Darazo 9 26 101 186 Birnin Kudu 3 Farming systems The Sorghum-Millet System predominates, though details vary with ethnic group. Communications are good with an all-weather road running through the area and domestic water supplies appear to be reasonable- Main characteristics Cowpeas are grown and groundnuts are grown for cash though surplus sorghum and other food crops are also sold. Near Miya town (in Land System 17), soils developed from aeolian deposits, are intensively cultivated and cropping is continuous with no fallow. Away from the town, the fallows get progressively longer until fallows of over 10 years commonly follow 12-16 years cropping. Farms are often 15-20 acres, larger than in many parts of the Bauchi Plains. The Hausas, who farm immediately around the town grow sorghum and millet as the main crops and cotton, rice, sugar cane and sweet potatoes on the fadamas. The Miyawa grow only sorghum and millet, with a little beniseed. They do not cultivate the fadamas which limits the range of crops grown. Both groups keep some cattle and draught animals. Constraints to production This area suffers the constraints that affect the whole of the Bauchi Plains. (see Part 4.) 34 Grazing The unfarmed land is intensively grazed in the wet season: in the dry season almost all available crop residues are eaten by local and migratory stock and any natural pasture heavily overgrazed. Forestry Poles and firewood are readily available from natural vegetation. There are no forest reserves or plantations in the area. 35 LAND SYSTEMS WITH THREE CROP OPTIONS This land occurs in all the Local Government Areas in the Bauchi Plains with the exception of Ningi. It occupies a large part of the Darazo and Misau Local Government Areas and occurs in the northern part of Alkalere, the Tafawa Balewa and Dasj.Local Government Areas and in some scattered areas in the southern part of the Toro Local Government Area. It is made up of 12 2 2 different land systems with a total area of 6 751 km (2 607 mi ) . The main characteristics are summarised in Table 11 and discussed below. Limitations to crop growth 1. Soil physical characteristics All the land systems in this group have no or only minor soil physical limitations to the growth of three of the crops considered: the soil limita tions are shown in Table 12. With the exception of Land System 34 which is 2 2 only 93 km (36 mi ) in area, the coarse-textured surface horizons together with either coarse material or imperfect drainage are limiting to maize. In Land System 34, the heavier textures, the poor drainage and presence of coarse material are limiting to millet and groundnuts. Shallowness, poor drainage, sandy textures and the presence of coarse material are limiting to cotton over all land systems in this group, except 34. 2. Soil chemical characteristics The chemical characteristics for which data are available are given in Table 13 and assessed as limitations to the growth of the crops considered. 36 TABLE 11 Summary of main characteristics of areas with three crop options Land Rangeland Crop Density of Present cropping Draught Erosion Extension system Occurrence Communicati ons and cattle Forestry options cultivation animals hazard centres no. Food Cash product ion 22,26 Millet Misau (LS 22, Intensive Millet Groundnuts Commonly LS 22 Slight Good. Main Misau Dr aught ani mals Trial plantings of S orghum 26) Sorghum Cotton in use LS 26 requires road crosses are stall fed. neem in Kurba forest Groundnuts Shira (LS 22) conservation works the land Little uncultivated reserve L.G.A system land available for grazing 34,35, Sorghum Toro, Jos Intensive Sorghum Excess None Moderate Poor None Little uncultivated No forest reserves 36 Millet (LS 34, 36) Millet food crops land available for or plantations Dass (LS 34) / Groundnuts firewood available Martgu (LS 36) grazing from nearby areas 4 Sorghum Toro Intensive Sorghum Cotton None Slight Good. Main Rinjin Gani Little uncultivated No forest reserves Jos & Bassa Millet Excess road crosses land available for or plantation, L.G.A. food crops the land grazing firewood available system from nearby areas 18,20, Sorghum 'DaraB.s Sparse Sorghum Groundnuts A few LS 18 Nil but rock Moderate to Miya, Satisfactory wet Trial plantings of 25 Millet (LS 18,20,25) Millet Eucalyptus in forest Misau & in use outcrops are poor. Darazo season grazing Groundnuts Birnin Kudu common reserves. Growth 2 (LS 20,25)! LS 20, 25 slight nr/ha/a. Firewood Shira (LS 20) collected from Bauchi & ÄJkaiere (LS natural vegetation 31 Sorghum Mainly in Sparse Sorghum Groundnuts Commonly Slight poor None Used for wet season No forest reserves. Millet Kanam .. Cotton in use grazing Firewood collected Groundnuts Tafawa from natural Balawa vegetation 8,10 Sorghum Bauchi, Alkalere (LS Mainly. S orghum Groundnuts None Moderate Variable but Nabordo Rangeland degraded Trial plantings of Millet 8 & 10)} sparse with Millet usually poor Bauchi by intensive use for Eucalyptus in forest Groundnuts Dai»a2;o, Toro pockets of wet and dry season reserves. Growth 2-5 Daas, Mangu (LS S) ; intensive grazing m /ha/a. Firewood Taf awa Balewa cultivation collected from Pankshin & 1 Kanam (LS 10) natural vegetation TABLE 12 Soil physical limitations to the growth of certain crops in areas with three crop options: crop options indicated by shading Land system Area to Maize Millet Sorghum Groundnuts Cotton Total area which SLC No. data refer Nature of Nature of Nature of Nature of Nature of , 2 .2 SLC SLC SLC SLC SLC km limitation limitation limitation limitation limitation km mi mi II J ' H I i IUI II 186 72 132 51 >6o wt >6o Nil > 60 >6o Nil ^60 WTa iniihiiMiui 2 56l 989 2 074 -*6o wt/wo >60 w/c >6o wt/tc 10-29 Nil 10-29 WTa 30-59 c 30-59 WTa/De 10-29 W D t < 111 T 1 IIIIIIIIIHIMIIHIIIIIIII miiimiii iinim.iii.i 1 nnhn HHHHHIIIH» 10 354 137 185 71 >6o tc >6o >6o tc >6o >6o D T C >IHH»1*IMM**"!'lllllll mumm MHMMIMM+I» 20 833 322 766 296 -*6o tc/tw 30-59 Nil 2 30-59 wt 1 30-59 Nil 30-59 WTa 10-29 w 3 10-29 C 3 10-29 C 30-50 D Ta C 10-29 C 4 10-29 tC/Wt 4 10-29 W/C minimin aiiiiinniiii.1 22 386 149 351 135 10-29 t 10-29 Nil 30-59 wt 30-59 Nil 10-29 t/w 30-59 wt/to 10-29 w/c 10-29 tC 10-29 C 10-29 wt 10-29 C 30-50 D T C t'+ K"*1»1!"!! NIIIHHHimiMHWIMfti 25 963 372 838 324 *60 wt/tö 1 10-29 Nil *6o wt/ta 30-59 Nil 10-29 t .2 30-59 w/t 30-59 c 10-29 WTa/TaC 4 IO-29 C 10-29 C 30-59 D/W Ta c •iiiiiiiiniiM »niiimttiHK ••11 nniiiiiiHiii 26 176 68 148 57 30-59 t 30-59 Nil 2 >6o 1 30-59 Nil 30-59 t 30-50 wtc/t0 30-50 wc/C 2 10-29 c 30-50 D Ta C 3 10-29 C »••••I'Mi'iT'iiiiiiiiiil illinium * •fHHtWHH«» nuiHiniiiniHUiiiniii 31 268 103 283 109 Ü60 ¥t/tC ^60 w/c ^60 i wt/tc 30-59 Nil 30-50 WTa 10-29 c 30-59 D Ta C 10-29 • C 34 93 36 72 28 30-50 Nil 30-50 t 1 30-50 Nil 30-50 t 30-50? 30-59 WTC 30-59 W C 4 30-59 w t c 30-59 w c 10-29! i• 10-291: ill 35 81 31 16 6 3 -*6o wt/tc 1 >6o Nil ?6o tc >6o Nil >6o ¥Ta/wc in in 1 36 418 l6l 347 134 3 ^60 wtAc 2 >6o 2 >6o . tc >60 $60 D Ta C * L •Limitation Depth Drainage Texture Coarse material D Severe W Severe No severe limitation _C_ Severe TT Moderate W Moderate Ta Moderate (Cotton only) C Moderate t Minor d Minor .w Minor c Minor Alternative limitations separated by an oblique stroke TABLE 13 Dominant soil chemical characteristics assessed as limitations to crop growth for land systems with three crop options (based on top 50 cm of soil profile) Limitations due to pH for Land CEC* Exch. K** pH P system meq % meq % Maize Millet Sorghum Groundnuts Cotton availability 4 4.63 0.16 5.3 Min Nil Min Min Nil Mod 8 4.5-15.5 0.2-0.3 5.9-6.4 Nil Nil Nil Nil Nil-Min Mod-Min 10 4.5 0.3 5.9 Nil Nil Nil Nil Nil Mod 18 4.5-11.5 0.16-0.24 5.3-6.3 Min-Nil Nil Min-Nil Min-Nil Nil-Min Mod-Min 20 4.6-15.5 0.16-0.2 5.3-6.3 Min-Nil Nil Min-Nil Min-Nil Nil-Min Mod-Min 22 5.3-15.5 0.16-0.24 5.6-6.3 Nil Nil Nil Nil Nil-Min Mod-Min 25 4.5-11.5 0.08-0.3 5.6-6.0 Nil Nil Nil Nil Nil Mod-Min 26 2.2-11.5 0.08-0.2 5.6-6.0 Nil Nil Nil Nil Nil Mod-Min 31 4.5-15.5 0.15-0.2 5.9-6.4 Nil Nil Nil Nil Nil-Min Mod-Min 34 9.8-10.5 0.15-0.28 5.4-6.3 Min-Nil Nil Min-Ni1 Min-Nil Nil-Min Mod-Min 35 4.6 0.16 5.3 Min Nil Min Min Nil Mod 36 4.5 0.3 5.9 Nil Nil Nil Nil Nil Mod *CEC meq %: >8 Suitable for intensive agriculture; 2.0-7.9 Requires a high ratio of fallow to crops, <2.0 Unsuitable for intensive agriculture (Adetunji, 1974) **K meq % for soils of pH >4.5: >0.10 Adequate; <0.10 Deficient /P availability related to pH: pH Limitations pH Limitations 6.5-7.5 Nil 5.0-5.9) 6.0-6.49) 8.1-8.5) Moderate - •-•, r, ~> Minor 7.51-8.0) <5.0 Severe Limitations to mechanical cultivation The predominant slopes in these areas are given in Table 14 together with the range of slopes found on the major facets of each land system. TABLE 14 Dominant slopes and slope range on major facets in areas with three crop options Slopes of ma; or facet Land Percent Degrees system Dominant Range Dominant Range 4 2.6 1.7- 5.2 1^ 1-3 8 3.5 1.7-10.5 2 1-6 io 8 3.5-10.5 4 2-6 18 0.9 0.2- 1.7 h h-1 20 1.7 0.9- 3.5 1 35-2 22 0.9 0.2- 1.7 h ^-1 25 1.7 0.9- 2.6 1 h-lk 26 1.7 0.9- 2.6 1 ^-l^ 31 2.6 1.7- 5.2 1^ 1-3 34 3.5 1.7- 5.2 2 1-3 35 4.4 1.7- 7.9 2h 1-4 36 4.4 1.7- 7.9 2^ 1-4 These figures show that only Land Systems 18 and 22 have slopes of less than 1% and should not require protection works but Land System 18 has numerous large rock outcrops. Land System 4, 20, 25, 26 and 31 mainly have slopes of 1-3%. Mechanised cultivation would need to be accompanied by conservation measures. The remaining land systems (8, 10, 34, 35 and 36) with slopes greater than 3% are not considered suitable for mechanised cultivation without elaborate conservation measures. In addition, Land Systems 8 and 10 occur interspersed with many rock outcrops, and Land Systems 34, and 35 are small and irregularly shaped. These factors would prevent the economic running of machinery except for high value crops. Soils with appreciable amounts of coarse material occur in Land Systems 18, 20, 22 and 34 and this may prove an additional limitation to mechanical cultivation. 40 Density and distribution of cultivation Reference to Separate Map 2, and Table 15 shows that Land Systems 22 and 26 in the Shira and Misau Local Government Areas are intensively cultivated. Land Systems 4, 35 and 36 occurring close to the Jos Plateau in the Jos, Toro, Tafawa Balewa and Mangu Local Government Areas are also intensively cultivated. Land System 20 in the Darazo Local Government Area has a high proportion of unused land. Land systems 8 and lO also have high proportions of unused land, but in Land System 8 it occurs as small scattered areas interspersed with many rock outcrops and in Land System 10 the slopes are steep. The remaining areas have small areas of intensive cultivation concentrated around villages with scattered cultivation elsewhere. Farming systems These areas include a wide variety of farming practices. They can be grouped into the two main systems found in the Bauchi Plains with variations related to both ethnic factors and intensity of cultivation. 1. The Millet-Sorghum System This predominates in the north east around Misau in Land Systems 22 and 26. Main characteristics Groundnuts and cotton, grown in roughly equal proportions>are the main cash crop with cowpeas interplanted in most mixtures. The area is intensively and almost permanently cultivated, with little fallow. Cattle including draught animals are kept, and some stall feeding is practised. Farmers with bulls may undertake ploughing on a contract basis for their neighbours. Constraints to production In addition to the constraints affecting the whole of the Bauchi Plains, the land around Misau has a high population density and intensity of cultivation, with nearly all land under continuous cultiva tion. There is almost no fallow land and farmers report declining yields indicating falling soil fertility. . 41 TABLE 15 Density of cultivation in areas with three crop options 2 Total Areas (km ) occupied by % of >10% Land area Local density of cultivation density (percentage) class system Government class in 2 2 Area forest km mi »60% 59-35% 34-10% <10% reserves 4 186 72 Toro 27 82 60 Jos 8 5 Bassa 4 8 2 561 989 Bauchi 158 209 194 393 24 Alkalere 2 45 40 145 Toro 25 85 159 190 41 Dass 7 3 Tafawa Balewa 25 93 96 16 Darazo 4 21 143 483 17 Birnin Kudu 1 5 Kan am 1 Jos 1 Mangu 4 7 6 10 *354 137 Pankshin 62 74 5 Kan am 21 30 2 Tafawa Balewa 25 6 16 6 Dass 1 1 Toro 5 2 Alkalere 46 11 Bauchi 35 6 18 432 167 Darazo 27 97 190 107 19 Bimin Kudu 3 9 4 11 20 833 322 Darazo 1 48 474 50- Bimin Kudu 4 14 56 108 Shira 8 53 77 Misau 1 1 31 22 386 149 Shira 90 76 40 28 Misau 59 63 22 13 25 963 372 Bauchi 39 51 14 19 Alkalere 6 io Darazo 97 103 193 Bim in Kudu 8 25 2 301 Misau 15 21 10 49 26 176 68 Misau 165 14 12 31 268 103 Kan am 37 99 25 18 Tafawa Balewa 33 43 5 8 34 93 36 Jos 26 15 5 14 Tafawa Balewa 2 6 Dass 2 6 8 Toro 3 6 35 *81 .31 Mangu 5 31 16 Jos 6 1 5 Tafawa Balewa 17 36 418 161 Mangu 2 17 — 5 ... 6 r -!OXj-ß.. .Uc oq A,-.. Jos ^JiM '-'-"-'; [ <>3' --.:•• i2.^. s.i'-.2 :•': Sri.'; ?--. £ Kanam,. r . . 6 9. .a. iJno: 'Tarawa'1" Balëwa -ó13 •' ••"-• eg' Is.ty p;i. ,TorO ... .^ lV.--: ':• , 6i 44 , r 22. 31 C_- k -•'BC 2 -,' '-' *Total area different from that in key on Seperate Map 1. Differences in LSIO arises from adjustment of boundary. 42 Grazing There is little uncultivated land available for grazing. The land that is available is used together with crop residues by local farmers for their work bulls. Forestry Trial plantings of neem have been established in the Kurba Forest Reserve. Little natural vegetation remains to provide a source of firewood and poles. Species such as Acacia nilotica, Acacia Senegal and neem would probably be the most successful for planting. 2. The Sorghum-Millet System This occurs throughout the rest of the Bauchi Plains and can be considered in four main areas. 2a. Land Systems 4, 34, 35, 36 occurring in the south west close to the Jos Plateau Main characteristics The farming systems have affinities with those on the Jos Plateau. Long season bulrush millet (dauro) acha (hungry rice) and cowpeas are grown in addition to sorghum. Maize is grown on the home farms and patches of yams, cocoyams and rice on wetter areas. The main cash crops on Land System 4 are cotton or sweet potatoes; elsewhere food crops are sold if there is any surplus. The area is intensively cultivated by hand, with little or no fallow. Cattle belong to the nomadic Fulani. Contraints to production In addition to the constraints affecting the whole of the Bauchi Plains, this land has a high population density and cultivation intensity, with little or no fallow and declining soil fertility, and poor communications, especially in Land Systems 35 and 36. Existing roads are orientated to Plateau State rather than to Bauchi. Grazing There is little uncultivated land available for grazing, but crop residues are grazed by nomadic pastoralists. 43 Forestry There are no forest reserves or plantations. Firewood and poles are still available from uncultivated land on nearby land systems 2b. Land Systems 18, 20, 25 in the north of Darazo Local Government Area Main characteristics Sorghum is again the most important crop grown either singly or interplanted with millet and cowpeas. It is grown both for food and cash. The main crop grown for cash is groundnuts, grown mainly on the home farms where the depredations of monkeys can be kept to a minimum. Cultivation is based on settlements, though the bush farms may be some distance from these and the Miyawa live on their farms during the growing season. The intensity of cultivation is generally low and there are large areas of uncultivated land. The fallows are long, at least lO years, following a 12 to 15 year cropping period. Cattle are often kept, and draught animals used on the ' farm. Constraints to production The constraints affecting the whole of the Bauchi Plains apply to these land systems. Grazing The large areas of uncultivated land are intensively grazed by nomadic cattle. Although fallows are often 10 years long the vegetation may be kept at an early stage of regeneration by this grazing. A cattle scheme is located near Darazo. Forestry A large part of Land System 20 falls within the Zala Forest Reserve and part of Land System 25 in the Farin Ruwa Reserve; in both reserves growth rates of planted eucalypts are mainly less than 2 m /ha/annum. Elsewhere there is plentiful uncultivated land for collection of firewood and poles. 2c. Land System 8 occurring as small scattered patches in much of the Bauchi Plains Main characteristics Cultivation is centred on small settlements. The farming systems vary in detail, but sorghum is the main crop throughout, with short 44 and long season bulrush millet and cowpeas. Groundnuts are the most important crop grown for cash; few others are grown. Cultivation is generally by hand. Fallows are over 10 years long, following 4-5 years cropping and there are large areas of uncultivated land. Cattle are not normally owned by the cultivators. Constraints to production This area suffers the constraints that affect the whole of the Bauchi Plains (see Part 4). Grazing Uncultivated areas are heavily grazed by nomadic cattle. A large 2 2 ranch of 140 km (54 mi ) has been established at Galambi, south of Bauchi. Forestry A number of forest reserves include parts of Land System 8 and trial plantings have been made of species of Eucalyptus. Growth rates are 3 never greater than 5 m /ha/annum and often less than 2. Land is available for the extraction of firewood and poles from natural vegetation. 2d. Land System 31 in the extreme south and south east of the Bauchi Plains Main characteristics The main crop is sorghum grown either sole or mixed with millet and cowpeas. Groundnuts are the main crop grown for cash but cotton and cowpeas are also grown for sale. Maize and early sorghum are grown on the home farms. The intensity of cultivation is low except near to the scattered villages, and the fallows are between 10-20 years, following 4-5 years cropping. There is plenty of unused land. Some livestock is kept, and draught animals are commonly used. Constraints to production In addition to the constraints that affect the whole of the Bauchi Plains Area, the area appears to have a particularly heavy infestation of Striga which limits grain production. 45 Grazing Uncultivated and fallow land is heavily grazed by nomadic cattle. No grazing reserves or cattle ranches have been established. Forestry There are no forest reserves or plantations in the area and firewood and poles are collected from the plentiful uncultivated land. 46 LAND SYSTEMS WITH TWO CROP OPTIONS This land occurs mainly in the Bauchi, Toro, Tafawa Balewa, Alkalere, Dass and Kanam Local Government Areas. It is made up entirely of Land System 27, 2 2 which totals 1 280 km (494 mi ). The main characteristics are summarised in Table 16 and discussed below. Limitations to crop growth 1. Soil physical characteristics The physical soil limitations are given in Table 17. This shows that there are no or only minor limitations to the growth of sorghum and groundnuts in at least 30-59% of the area. The presence of coarse material and imperfect drainage is thought to present a moderate limitation to maize and millet^ whilst shallowness together with imperfect drainage and coarse material present a severe limitation to cotton. 2. Soil chemical characteristics The chemical characteristics for which data are available are given in Table 18 and assessed as limitations to the growth of crops considered. 47 TABLE l6 Summary of main characteristics of areas with two crop options Land Present cropping Rangeland Crop Density of Draught Erosion Extension system Occurrence Communications and cattle Forestry no. options cultivation Food Cash animals hazard coverage production 27 Sorghum Scattered Sorgbjm Slight Trial plantings Groundnuts occurrences in Millet of Eucalyptus a) Toro or a) Moderate to a) Excess a) None a) Poor a) None a) Little in the Jawo Bauchl intensive food uncultivated Forest Reserve Developnmb crops land avail Areas able for - grazing b) Alkalere b) Moderate to b) Ground b) Conmahty b) Moderate b) Alkalere b) /Little Firewood and Develop intensive nuts in use Secondary uncultivated poles collected ment Area Cotton road and avail from natural crosses able for vegetation the land grazing syst em c) Liman c) Sparse c) Ground c) Few in c) Moderate c) Ringim c) Used for wet Katagum nuts, use Secondary Ganyi season and Toro Cotton roads cross grazing Develop the land ment Areas system •Administrative units pre-1976 in this table TABLE '17 Soil physical limitations to the growth of certain crops in areas with two crop options: crop options indicated by shading Land system % Soil limitation category (SLC) by crop in each land system, with nature of limitation* Area to Maize Millet Sorghum Groundnuts Cotton Total area which SLC data refer Nature Nature Nature Nature Nature No. of of of of of SLC % SLC % SLC % SLC % SLC % .2 . 2 .2 limita limita km km limita limita limita mi mi tion tion tion tion tion 27 1 280 494 1 126 435 3 >60 tC/wt 3 >60 C/wc 2 ; 30-59: t 2 30-59 c 4 30-59 T Wc 3 : 10-29 tC 3 10-29 C 5 30-50 DTC 4 i10-29 W/t,C 4 10-29 w/tc limitations Depth Drainage Texture Coarse material D Severe W Severe No severe limitation C Severe D Moderate W Moderate T Moderate (cotton only) C Moderate d Minor w Minor t Minor c Minor Alternative limitations separated by an oblique stroke. TABLE 18 Dominant soil chemical characteristics assessed as limitations to crop growth for land systems with two crop options Limitations due to pH for Land CEC* Exch. K** pH P system meq % meq % Maize Millet Sorghum Groundnuts Cotton availability 27 4.5-15.5 0.2-0.3 5.9-6.4 Nil Nil Nil Nil Nil-Min Min *CEC meq %: 8 Suitable for intensive agriculture; 2.0-7.9 Requires a high ratio of fallow to crops, 2.0 Unsuitable for intensive agriculture (Adetunji, 1974) **K meq % for soils of pH>4.5: >0.10 Adequate; <-0.10 Deficiency /P availability related to pH: pH Limitations 6.5-7.5 Nil 6.0-6.49) M. „ 7.51-8.0) Min°r 5.0-5.9 > M A *. 8.1-8.5 ) Moderate <5.0 Severe Limitations to mechanical cultivation The predominant slopes in these areas are given in Table 19 together with the range of slopes found on the major facets of each land system. TABLE 19 Dominant slopes and slope range on major facets in areas with two crop options Slopes of major facet Land Percent Degrees system Dominant Range Dominant Range 27 2.6% 1.7-5.2% 1>° 1-3° These figures show that Land System 27 has slopes greater than 1% and will require mechanical and other conservation works. Soils with coarse material present occur in this Land System and may present a further limitation to mechanised cultivation. Density and distribution of cultivation Reference to Separate Map 2 and Table 20 shows that much of this area is only sparsely cultivated. Most of the intensive cultivation occurs in Bauchi, Tafawa Balewa, and Alkalere Local Government Areas and in the small area lying within the Toro Local Government Area. 51 TABLE 20 Density of cultivation in areas with two crop options 2 Areas (km ) occupied by density of cultivation % of <10% Total area Local (percentage) class density . Land Government class in system Area forest . 2 .2 "»60% 59-35% 34-10% km mi <10% reserves 27 1 280 494 Bauchi 95 138 125 56 Toro 19 63 57 82 85 Alkalere 79 67 8 Tafawa Balev/a 87 175 122 35 Dass 4 14 9 7 Kanam 23 15 Farming systems The Sorghum-Millet System predominates with local variations dependent on the ethnic groups and intensity of cultivation. The variations can be described in three areas. a. The south-west close to the Jos Plateau Main characteristics In the intensively cultivated areas^long season millet (Dauro or Murun) is sometimes substituted for sorghum. The millet is often transplanted. Acha (hungry rice) is often grown for food, and surplus food crops are commonly sold for cash. Groundnuts and cotton are not extensively grown. Where fadamas are available, a little rice, sugar cane and some cocoyams and cassava are cultivated. All operations are done by hand. Often cropping is continuous except on the edges of the area where fallows of up to 4 years follow 4 or 5 years cropping. Constraints to production In addition to the constraints that affect the whole of the Bauchi Plains, this land has poor communications with Bauchi and a high density of population and consequent land shortage. Grazing There is little uncultivated land available for grazing and there are no grazing reserves established in the area. 'Forestry There has been no planting of any species in this area, even on a trial basis. b. The south-east around Gukaru town Main characteristics The main crops in this densely cultivated area are sorghum and millet with cówpeas; groundnuts and some cotton are grown as cash crops. Some rice and sugar cane, are grown in wetter areas near streams. 53 Cultivations away from the settlements include short fallows, but most land is fully used. Frequently draught animals are used in addition to hand cultivation. Communications and water supplies are good. The nearby inhospitable land has probably resulted in a concentration of cultivation in this area. Constraints to production In addition to the constraints that affect the whole of the Bauchi Plains there is a high population density and consequent land shortage. Much of the nearby land is poor and rocky so there is little room for expansion. Grazing There is little uncultivated land available for grazing and there are no grazing reserves established in the area. Forestry No plantations have been established and there are no forest reserves in the area. c. Other scattered areas of Land System 27 Ma'in characteristics These areas are less intensively cultivated and near Nabordo form part of a forest reserve. Apart from the area immediately around Liman Katagum, farming is scattered, centred on small villages and hamlets each with small patches of intensive cultivation. The Sorghum Millet System prevails, with cowpeas for cash and food, and groundnuts and occasionally cotton grown for cash. Where there is suitable fadama land, rice and sugar cane are grown on a small scale. Fallows away from villages are at least 10 years, following 5 or 6 years cropping. Draught animals are occasionally kept. Constraints to production These areas suffer the constraints that apply to the whole of the Bauchi Plains. Communications with Bauchi are particularly poor south of the Gongola and Maijuju Rivers. 54 Grazing The land is used for wet season grazing. There are no grazing reserves or ranches established on this land. Forestry Trial plantings of Eucalyptus have been made in the Jauro Forest Reserve. Growth rates of 5 m /ha/annum were recorded. There is sufficient uncultivated land to provide all the requirements for firewood and poles. 55 LAND SYSTEMS WITH ONE CROP OPTION This land occurs in the Bauchi, Alkalere, Tafawa Balewa, Dass, Pankshin and Kanam Local Government Areas. It is made up of Land Systems 28', 29, 30 with 2 2 a total area of 1 lOo Km (427 mi ). The main characteristics are summarised in Table 21 and discussed below. / Limitations to crop growth 1. Soil physical characteristics The physical soil limitations are given in Table 22. This shows that there are no physical soil limitations to the growth of groundnuts in at least 30-59% of all the land systems. Sandy texture, coarse material and poor drainage combine to present limitations to maize, sorghum and cotton whilst coarse material and poor drainage affect millet. Although all the land systems have areas with only minor limitations to the growth of millet and sorghum, the remainder of the land system has moderate limitations to the growth of these crops. 2. Soil chemical characteristics The chemical characteristics for which data are available are given in Table 23 and assessed as limitations to the growth of the crops considered. 56 TABLE 21 Summary of main characteristics of areas with one crop option 1 Land Present cropping Rangeland Crop Density of Draught Erosion Communica Extension system Occurrence and cattle Forestry options cultivation animals hazard tions centres no. Food Cash production 29 Groundnut Single Intensive Sorghum Surplus None Moderate. Very poor None Little No forest ocur- Millet food Conserva uncultiv reserves. rence in tion ated land Tafawa crops Firewood Balewa & works available and poles Pankshin necessary for collected Local grazing from Govern nearby ment areas Areas 28, Groundnut Scattered Sparse Sorghum Ground Few in Slight. Moderate Liman Rangeland Firewood 30 occur Millet nuts use Conserva to poor Katagum in danger and poles rences in tion Tafawa of degrad collected Alkalere, works Balewa ation due from Tafawa necessary to use for natural Balewa & wet and vegetation Kanam dry season (LS 28 & 30) grazing Bauchi & Dass (LS 28) LGA TABLE 22 Soil physical limitations to the growth of certain crops in areas with one crop option: crop option indicated by shading Land system % Soil limitation category (SLC) by crop in each land system with nature of limitation* Area to Maize Millet S orghum Groundnuts Cotton Total area' which SLC No. data refer Nature Nature Nature Nature Nature of of of of 1 of SLC % SLC % SLC % SLC % SLC % 2 2 .2 km mi km limita limita limita limita limita mi 1 tion tion tion tion tion 7 28 560 216 493 190 3 ^60 tc/wt 1 10-29 Nil 2 30-50 t w/c 1 30-50 Nil 3 10-29 Taw 2 30-59 C 3 30-50 t C 3 30-50: c 4 10-29 D TaC 3 10-29 w/c en 5 30-59 CO 29 138 53 113 44 3 30-50 t w 2 30-50 w 2 30-50 t w 1 30- 50 Nil 3 30-50 TaD 4 30-59 t C 4 30-59 C 4 30-59 t C 5 30-59 C 5 30-59 D T C 30 408 157 359 139 3 30-59 t w 2 30-59 w 2 30-59 t w 1 30-59 Nil 1 3 30-59 TaD 4 30-59 t C/W 4 30-59 w/c 4 30-59 t C/W 5 30-59 w/c ; 4 10-29 W t JL 10-29 D TaC *Limitations Depth Drainage Texture Coa rse material D_ Severe W Severe No severe limitation C Severe D Moderate W Moderate T Moderate (Cotton only) C Moderate d Minor w Minor t Minor c Minor Alternative limitations sejJarate d by oblique stroke TABLE 23 Dominant soil chemical characteristics assessed as limitations to crop growth for land systems with one crop option Limiations due to pH for CEC* Land Exch. K** pH P system meq % meq % Maize Millet Sorghum Groundnuts Cotton availability 28 4.9-11.5 0.08-0.24 5.3-6.3 Min-Nil Nil Min-Ni1 Min-Ni1 Nil-Min Mod-Min 29 4.5-15.5 0.2 -0.3 5.9-6.4 Nil Nil Nil Nil Nil-Min Mod-Min 30 4.5-15.5 0.15-0.2 5.9-6.3 Nil Nil Nil Nil Nil-Min Mod-Min *CEC meq %: >8 Suitable for intensive agriculture f 2.0-7.9 Requires a high ratio of fallow to crops, <2.0 Unsuitable for intensive agriculture (Adetunji, 1974) **K meq % for soils of pH>4.5: >0.10 Adequate; <0.10 Deficient /P availability related to pH: pH Limitations 6.5-7.5 Nil 6.0-6.49) 7.51-8.0) Min°r Ï.ZÏ.I> Moderate <5.0 Severe Limitations to mechanical cultivation The dominant slopes in these areas are given in Table 24 together with the range of slopes on the major facet of each land system. TABLE 24 Dominant slopes and slope range on major facets in areas with one crop option Slopes of major facet Land system Percent Degrees Dominant Range Dominant Range 28 1.7 0.9-3.5 1 h-2 29 3.5 1.7-5.2 2 1-3 30 2.6 1.7-3.5 I's 1-2 These figures show that Land System 29 with slopes greater than 3% is not suitable for large scale mechanised farming. Land Systems 28 and 30 with slopes between 1 and 3% will require mechanical and other conservation measures before being used for mechanical farming. Soils with appreciable amounts of coarse material occur in each of these land systems and this may prove an additional limitation to mechanised cultivation. Density and distribution of cultivation Reference to Separate Map 2 and Table 25 shows that Land System 29 is intensively cultivated. Land System 28 is only intensively cultivated around Liman Katagum. The remainder, together with most of Land System 30 is only sparsely cultivated. Farming systems The Sorghum-Millet predominates but can be considered in two areas(a) Land System 29 in the extreme south west, close to Jos Plateau, where cultivation 60 TABLE 25 Density of cultivation in areas with one crop option 2 Areas (km ) occupied by density of % of <10% Total area Local density Land cultivation (percentage) class Government system class in . 2 .2 Area forest km mi >60% 59-35% 34-10% 28 560 216 Bauchi 44 102 38. . 18 . 53 Alkalere 26 6 3 Dass 17 51 29 5 Tafawa Balewa 45 58 75 .; 27 Kanam 7 9 29 138 .. •, 53 Tafawa" Balewa 13' 8 60 ' 16 ' Pankshin 35; 6 30 408 157 Alkalere • 19 7 2; Toro '?•' 4 Dass 1 - Tafawa Balewa 105 86 17 Kanam 82 68 '', 3 6 • Pankshin 1 3 ______is intensive, and, b) Land Systems 28 and 30, mainly scattered over Tafawa Balewa, Kanam and Alkalere Local Government Areas/which are sparsely cultivated. a. Land System 29 Main characteristics Although the most important crop is sorghum it is frequently replaced by long-season millet. Normally cowpeas are interplanted and Acha is an additional food crop, with some rice on suitable wetter areas. Cash crops are of far less importance than food crops, but include a little cotton; surplus food crops such as cowpeas and rice are sold. Groundnuts are only grown for local consumption. All operations are by hand and land is usually under continuous cropping, there being very little fallow or uncultivated land suitable for farming. The few cattle are in the hands of mainly settled Fulani. Constraints to production In addition to the constraints affecting the whole of the Bauchi Plains, this land suffers from: 1. Very poor communications orientated to Pankshin Local Government Area of Plateau State rather than to Bauchi. This has a marked effect on every aspect of life here. 2. No extension coverage, and few if any agricultural inputs, such as fertilizer. 3. A very high population density resulting in intensive cultivation and small farms with declining soil fertility. Grazing There is little uncultivated land available for grazing. Forestry Although there is little natural vegetation to provide firewood and poles,these are collected from nearby areas. 62 b. Land Systems 28 and 30 Main characteristics The area is very sparsely cultivated, except around Liman Katagum. The population is scattered in villages and hamlets on which the cultivation is centred: patches of permanent cropping are found in some lowland areas. Cowpeas are grown together with sorghum and millet, both as a food and cash crop, with small amounts of groundnuts and occasionally cotton grown for cash. Rice and sugar cane are grown on a small scale on fadama land. Land is usually cropped for about 5 years and left fallowed for at least 10 years, depending on fertility and availability of land. Cultivations are usually by hand, but draught animals are found throughout the area. Constraints to production In addition to the constraints affecting the whole of the Bauchi Plains,land lying to the south of the Maijuju River has particularly poor communications with Bauchi. Grazing These areas are mainly used for wet season grazing by nomadic cattle. Forestry- There is abundant uncultivated land.and firewood and poles are collected from the natural vegetation. AREAS WITH MODERATE OR SEVERE LIMITATIONS TO ARABLE CROPS These are areas with a high proportion of land in which the soil characteristics present moderate or severe limitations to the growth of maize, millet, sorghum, groundnuts and cotton. They occur throughout the Bauchi Plains, but a large area occurs in the north west in the Toro and Ningi Local Government Areas. They total 2 2 8 071 km (3 115 mi ). The main characteristics are summarised in Table 26 and discussed below. 63 TABI£ 26 Summary of main characteristics of areas with moderate or severe limitations to arable crops Present cropping Rangeland Land Crop Density of Draught Erosion Extension Occurrence Communications and cattle system options cultivation animals hazard centres Food Cash production Tor», 3 Nil Tafavs Baleva, Intensive Sorghum Groundnuts None Mode rate Mainly poor Rinjin Gaino Rangeland Jos. Barakin though main Ladi, Bassa, Millet Sorghum for one area degraded by .Mangu, CDwpeas road crosses uncontlDlle•d• use Pankshin part of land for wet and system dry season grazing 6 Nil -Toro Slight None Slight Poor None 7 Nil Darazo, Mainly None Slight Poor,though Bauchi Toro, intensive main road Bauchi crosses parts of land system 12 Nil Toro, Mainly None Slight Poor Variable Variable Alkalere, slight to Dass, moderate Kan am Tafawa Balewa 14 Nil Darazo, Slight None Slight Moderate. Variable Rangeland Toro, Main and mainly degraded Bauchi, secondary by uncontrolled Dass( roads cross use for wet and Pankshin, several parts dry season Tafawa of the land grazing Balewa system 15 Nil Darazo, Slight Sorghum Groundnuts None Slight Poor None Satisfactory Torof Millet Sorghum wet season Bauchi. CDwpeas Beniseed grazing Rice 16 Nil Ningi, Slight Sorghum Groundnuts None Slight Very poor None Satisfactory Toro Millet Sorghum wet season Cowpeas grazing 19 Nil Darazo, Slight None Nil to Poor Miya Satisfactory Shira, slight wet season Birnin Kudu grazing 21 Nil Ningi, Slight None Slight Poor though None Toro to track crosses . severe part of the land system 33 Nil Jos Slight None Slight Poor None Rangeland Dass to degraded by Toro moderate uremtroUed use for wet and dry season grazing 64 Limitations to crop growth The physical soil limitations are given in Table 27 and the chemical characteristics in Table 28. Limitations to mechanical cultivation These areas have inherent soil limitations to crop growth and in addition the figures in Table 29 shows that Land Systems 3, 21 and 33 with slopes greater than 3% have a severe erosion hazard. All the other land systems except 19 would require strict conservation measures if they were to be used for mechanised agriculture and the complexity of the lay out would prevent the economic running of machinery, except for high value crops. TABLE 29 Dominant slopes and slope range on major facets in areas in which there are moderate or severe soil limitations to arable crop$ Slopes of major facet Land Degrees system Percent Dominant Range Dominant Range 3 3.5 1.7-10.5 2 1-6 6 1.7 1.7- 3.5 1 1-2 7 1.7 0.9- 3.5 1 ^-2 12 2.6 1.7- 5.2 1^ 1-3 14 1.7 0.9- 2.6 1 ^-l^ 15 1.7 0.9- 3.5 1 h-2 16 2.6 1.7- 3.5 I3* 1-2 19 0.9 0 - 1.7 h O-l 21 5.2 3.5-10.5 3 2-6 33 3.5 1.7- 5.2 2 1-3 65 TABLE 27 Soil physical limitations to the growth of certain crops in areas with moderate or severe limitations to crop growth % Soil limitation category (SLC) by crop in each land system with nature of Land system limitation* Area to Maize Millet Sorghum Groundnuts Cotton Total area which SLC Nature Nature No. data refer Nature Nature Nature of of of of SLC % SLC % SLC % of SLC % SLC % .2 . 2 .2 limita limita limita km mi km limita limita mi tion tion tion tion tion 3 1 062 410 754 291 3 30-59 tc 3 30-59 C 3 30-59 tc 3 30-59 C 5 30-59 DTaC 4 10-29 Wt 4 10-29 W 4 10-29 Wt 4 10-29 W 4 10-29 W 10-29 Rock 10-29 Rock 10-29 Rock 10-29 Rock 10-29 Rock 6 119 46 89 34 3 60 t w/c 2 30-59 c 2 30-59 tw/tc 2 30-59 c 4 30-59 t c D/W 3 30-50 C 3 30-50 C 3 30-50 C 5 30-50 DtC 7 487 188 375 145 3 60 t C 3 60 C 3 60 tc 3 60 C 5 60 D T C 12 155 60 119 46 3 10-29 w t 2 10-29 w . 2 10-29 wt 1 10-29 Nil . 4 10-29 WTac 4 30-59 tw/c 4 30-59 W/C 4 30-59 tw/tc 4 30-59 W/C 5 30-59 TaW 14 447 173 331 128 4 60 tc 4 60 C 4 60 t C 4 60 C 5 60 DTaC 15 2 426 937 1 722 664 3 30-59 tc 2 30-59 c 3 30-59 t c 2 30-59 c 4 30-59 TaW/Dc 4 10-29 Wt 4 10-29 W 4 10-29 W t 4 10-29 W 5 10-29 DTaC 16 690 266 538 208 3 60 tc 3 60 c 3 60 t C 3 60 C 5 60 DTaC 19 476 184 428 165 3 10-29 tC/wt 3 10-29 c 2 10-29 t 1 10-29 Nil 5 60 DTaC 4 30-59 tw/c 4 30-59 w/c 3 10-29 t c 3 10-29 C 4 30-59 t w/c 4 30-59 W/C 21 224 86 185 71 3 60 tc 3 60 c 3 60 tc 3 60 C 5 60 DTaC 33 53 20 47 18 4 60 tc 4 60 c 4 60 tc 4 60 C 5 60 DTaC •Limitation Depth Drainage Texture Coarse material D Severe W Severe T No severe limitation Q Severe D Moderate W Moderate Ta Moderate (cotton only) C Moderate d Minor w Minor t Minor c Minor Alternative limitations separated by oblique stroke TABLE 28 Dominant soil chemical characteristics assessed as limitations to crop growth for land systems with moderate or severe limitations to arable crops (.top 50 cm of soil profile only) Limitations due to pH for Land CEC* Exch. K** pH system meq % meq % P Maize Millet Sorghum Groundnuts Cotton availability • 3 4.5-10.5 0.15-0.3 5.9-6.3 Nil Nil Nil Nil Nil-Min Mod-Min 6 5.6-11.2 0.19-0.24 5.3-5.8 Min-Nil Nil Min-Nil Min-Nil Nil Mod 7 4.5-11.5 .0.24-0.3 5.6-5.9 Nil Nil Nil Nil Nil Mod 12 5.2-15.5 0.16-0.24 5.6-6.4 Nil Nil Nil Nil Nil Mod-Min 14 4.5-11.5 0.08-0.23 5.6-5.9 Nil Nil Nil Nil Nil-Min Mod 15 4.5-10.5 0.15-0.3 5.6-6.3 Nil Nil Nil Nil Nil Mod-Min 16 4.5-10.5 0.15-0.3 5.6-6.2 ^Nil Nil Nil Nil Nil-Min Mod-Min 19 4.5-11.5 0.08-0.23 5.6-5.9 Nil Nil Nil Nil Nil-Min Mod 21 4.5-10.5 0.15-0.3 5.9-6.3 Nil Nil Nil Nil Nil Mod-Min 33 5.2-9.8 0.2-0.28 5.4-5.8 Min-Nil Nil Min-Nil Min-Nil Nil-Min Mod *CEC meq %: >8 Suitable for intensive agriculture; 2.0-7.9 Requires a high ratio of fallow to crops, <2.0 Unsuitable for intensive agriculture (Adetunji, 1974) **K meq % for soils of pH >4.5: >0.10 Adequate; <0.10 Deficient /P availability related to pH: pH Limitations pH Limitations 6.5-7.5 Nil 5.0-5.9) M , . 6.0-6.49^ ~ ^ ,~i) 8.1-8.5) Moderate Minor 7.51-8.0) "J-««* ^5<0 Severe Soils with much coarse material occur widely in all these land systems except 15. This is an additional limitation to mechanised cultivation. Density and distribution of cultivation Reference to Table 30 and Separate Map 2 shows that most of this land is only sparsely cultivated. Land System 3 to the east of Panshanu is an exception, due possibly to people from hill villages settling on the flatter areas below. The area around Bauchi Town is also intensively cultivated but this is due to the urban centre. Farming systems The Sorghum-Millet System predominates but farming in Land System 15 which occurs over a large part of the east of the Toro Local Government Area, the west of the Darazo Local Government Area and the north of the Bauchi Local Government Area is distinct from that in the remaining areas. a. Land System 15 Main characteristics Cultivation is centred around a few settlements and this description is based on data collected at Ringim, a village to the east of Kafin Madaki. With the exception of the intensively cultivated home farms, much of the upland has been left uncultivated or under long fallow. The heavier soils of the floodplain areas are used for farming as farmers found crop production to be more reliable, particularly during the recent drought years. The farming system is based on sorghum and millet with cowpeas. Groundnuts, sorghum and a little beniseed and rice are grown for cash. Due to monkey and other animal damage, most crops except sorghum and cowpeas are grown on the home farm. All cultivation is by hand and there are no cattle owned by the farmers. When upland areas are used they are cropped for about 7 years, followed by about 20 years fallow. On the fadamas cropping is for about 20 years, followed by 10 years fallow. There is no shortage of uncultivated land on both upland and fadama. 68 TABLE 30 Density of cultivation in areas with moderate or severe limitations to arable crops Total area Areas (km2) occupied by density of cultivation (percentage) class % of>10% Local density Land Government class in system Areas forest km2 mi2 >60% 59-35% 34-10% <10% reserves 3 1 062 410 Toro 21 191 200 182 32 Tafawa Balewa 6 14 50 24 Bassa 4 34 18 Jos 37 32 25 . 15 Barakin Ladi 1 3 Mangu 16 Pankshin 103 11 9 66 6 119 46 Toro 4 25 67 23 11 7 487 188 Bauchi 52 101 145 97 31 Toro 7 31 45 6 Darazo 3 12 155 60 Alkalere 3 Toro 1 11 18 22 36 Dass 15 22 16 4 Tafawa Balewa 2 11 9 Kanam 1 11 9 14 447 i73 Bauchi 13 33 40 43 55 Toro 7 11 15 9 44 Dass 27 30 21 8 Darazo 12 32 56 7 Tafawa Balewa 50 23 7 1 Kanam 1 5 Pankshin 1 2 15 2 426 937 Bauchi 2 39 94 3 Toro 3 10 119 896 Darazo 28 153 624 18 Ningi '5 50 403 16 690 226 Toro 4 87 500 75 Ningi 99 19 476 Darazo 5 20 83 188 Bi.-flin Kudu 3 21 23 92 Shira 6 3 32 21 224 86 Toro 29 58 Ningi •'• '6. 28 161 33 53 20 Jos 24 17 3 2 Dass • . • 3 3 Toro 1 69 Constraints to production These areas suffer from the constraints that affect the whole of the Bauchi PJains but due to the scattered isolated nature of settlements constraints due to lack of roads or services are more severe than usual. Grazing The area is used for wet season grazing and to a more limited extent for dry season grazing by cattle from north of the Bauchi Plains. Tsetse . eradication is at present in progress in the area and makes additional grazing areas available. Forestry Forest reserves at Jauro, Sumu and much of the Lame/Burra Game and Forest Reserve occur on Land System 15. Trial plantings of Eucalyptus have been made at Jauro. Elsewhere firewood and poles are obtained from natural vegetation. b. Land Systems 3, 6, 7, 12, 14, 16, 19, 21, 33 Main characteristics Where farming occurs it is based on sorghum and millet, with groundnuts grown for cash. Cowpeas are usually intercropped for cash and food,and patches of cassava and sweet potatoes add to the diet. Cattle are not usually kept and all cultivation is by hand. Except in the intensively cultivated areas the cropping period is short, usually 2 to 4 years and the fallow anything up to lO years. Constraints to production These areas suffer the constraints that affect the whole of the Bauchi Plains. Grazing The uncultivated areas are used for wet season grazing. There are no grazing reserves or cattle ranches. 70 Forestry Parts of the forest reserves at Jarawa, Golambe, Kir Hill, Tala Hill and Dutson Bello occur on land systems 3, 7 and 14. Trial plantings of Eucalyptus have been made. Firewood and poles are readily available from natural vegetation in all these areas. 71 AREAS UNSUITABLE FOR ARABLE CROPS These are areas that are unsuitable for arable crops because they have either a very high proportion of bare rock or are severely gullied. Rocky hills and mountains and complex areas of low rock outcrops interspersed with small pockets of soil are included. These areas occur throughout the Bauchi Plains but are particularly common along the watershed between the Chad and Gongola drainage basins, roughly the line of the main road from Jos to Bauchi and Darazo. They occupy a total of 6 766 km2 (2 612 mi2). Land Systems 1, 2, 11, 13 and 32 are included. Soil limitations to crop growth The absence of soil over most of these areas precludes the growth of crops, but small patches of sandy or gravelly soils occurring between rock outcrops support some crops. Density and distribution of cultivation Reference to Separate Map 2 and Table 31 shows that most of these areas are uncultivated, but small scattered fields are found amongst the rocks in places. Table 31 also includes details of cultivation density in fadama floodplains which have not been included in this survey. Grazing Many of these areas are used for wet season grazing but the grass cover is sparse. Forestry These land systems occur in many forest reserves. In fact they should all be designated reserves to protect them from erosion or to prevent excessive runoff of rain water to the surrounding slopes. 72 TABLE 31 Density of cultivation in areas unsuitable for farming and in fadama floodplains (LS5) % of 10% ; Total area Local Areas (km2) occupied by density of cultivation (percentage) class Land density Government system 2 2 forest • km mi Areas >60% 59-35% 34-10% <10% reserves 1 1 537 593 Bauchi 85 61 25 75 55 Alkalere 17 3 1 1 Toro 138 39 35 427 65 Darazo 2 13 36 139 11 Dass 123 18 3 1 10O Tafawa Balewa 24 19 6 1 Ningi 31 Birnin Kudu Kanam 83 32 2 Bassa 1 Jos 6 1 1 3 Barakin Ladi 1 Mangu 32 11 9 2 Pankshin 19 12 2 1 865 720 Bauchi 54 49 124 257 14 | Alkalere 1 3 20 146 Toro 29 48 132 174 42 Darazo 18 135 338 13 Dass 2 Ningi 1 115 Birnin Kudu 1 • 1 5 Tafawa Balewa 19 9 45 4 Shira 3 3 Kanam 23 31 4 1 Bassa 2 Jos 3 4 2 1 2 1 Barakin Ladi 1 Mangu 31 10 9 Pankshin 2 m 5 Bauchi 7 li 2 239* 92 Alkalere 5 8 1 Toro i 8 80 52 Darazo 4 10 10 54 35 Tafawa Balewa 5 7 Ningi 7 2 Kanam 3 5 ' Jos 4 2 2 11 534 206 Toro 5 9 477 67 Ningi 43 13 1 464 565 Bauchi 44 39 50 123 21 Alkalere 6 21 9 Toro 20 61 128 206 36 Darazo 30 138 30 Dass 26 53 12 Tafawa Balewa 107 102 92 31 Ningi 1 1 10 Birnin Kudu 7 8 21 Kanam 30 21 Shira 4 Jos 13 8 5 3 Bassa 2 12 4 Mangu 1 io 5 23 226 87 Bauchi 32 8 3 1 Alkalere 13 9 13 19 Darazo 7 35 Kanam 24 58 4 24 116 45 Bauchi 1 Alkalere 2 1 49 Darazo 6 Kanam 24 29 3 1 32 1 366* 527 Bauchi 55 17 16 5 Alkalere 186 35 4 44 Toro 22 22 18 13 Dass 12 7 1 Tafawa Balewa 51 33 11 10 Kanam 216 75 3 2 Langtang 2 14 Pankshin 238 250 4 37 94 36 Tafawa Balewa 11 47 26 IO 39 3* 1 Kanam 3 40 18 7 Birnin Kudu 6 4 8 *Total area different from that in key on Seperate Map 1. Differences in LS5 and 39 arise from the elimination of many small areas during map reduction; in LS32 adjustment arises from alteration in the southern boundary of the physiographic region. 73 Part 4 I Part 4 Agricultural development possibilities TYPES OF DEVELOPMENT Different types of agricultural development have been considered with reference to the Third National Development Plan 1975-80 and discussions with Federal and State authorities and the staff of research institutes in Nigeria. The definitions given in Table 32 and in the following sections of this report are based on these discussions and experience of similar development projects in Nigeria. The areas in which the various types of development could take place are shown in Table 33 in relation to both administrative units and land systems. Similarly areas in which the environmental limitations for particular crops are at a minimum are shown in Table 34 in relation to both administrative units and land systems. It must be emphasised that the various development possibilities have been assessed on environmental criteria. No attempt has been made to rank them in economic terms. ASSESSMENT OF AREAS FOR PARTICULAR TYPES OF DEVELOPMENT Any particular form of development should result in increased agricultural production almost anywhere in the Bauchi Plains, but to be most effective it should be located in areas where environmental and present land use limita tions are at a minimum. In assessing whether an area is suitable for a particular type of developmenttthe following factors have been considered within the framework of land systems: Climate Size and distribution of the land system Soil limitations to crop growth Slopes in relation to erosion hazard Distribution and intensity of present cultivation Present farming systems Existing extension coverage Present grazing status and cattle movements Existing forestry activities Communications The criteria used to assess the suitability of an area for the types of agricultural development are summarised in Table 34A. The page numbers given in the first column refer to the paaes in which the development is described. 75 TABLE 32 Types of agricultural development Type of development Summary definition of development Establishment of integrated agricultural development projects aimed at increasing existing agricultural production per ha by (a) In densely improving infrastructure (communications, supply of agricultural inputs, produce marketing, credit facilities and extension cultivated areas service coverage). Run by a semi-autonomous project authority and making use of self-help wherever possible. Allied to general 1. Integrated improvement of social services. agriculture (b) In sparsely As above but also able to increase production by increasing the area under cultivation and/or introducing 'mixed farming'. cultivated areas Establishment of large mechanised farms (* 1 000 ha) requiring a high level of management expertise and mechanisation of all 2. Mechanised farming stages of production from land preparation to harvest. Good planning and adequate conservation measures are essential. Limited to sparsely cultivated areas. Improvement of traditional grazing including control of flock numbers, the elimination of unregulated pruning and the introduction 3= Traditional grazing of forage species into natural grassland. These measures, together with the establishment of grazing reserves and the allocation of grazing rights, are components of a suggested programme to be organised at inter-State level. Limited to sparsely cultivated areas. Establishment of reserves in the major traditional wet and dry season grazing areas and along migration routes, with additional 4« Grazing reserves reserves within areas free or being freed of tsetse by the eradication programme. Provision of adequate water supplies, veterinary services and improved natural grassland, coupled with strict control of stock numbers. Limited to sparsely cultivated areas. Establishment of ranches for 'growing out' cattle drawn from Pulani herd. Stock numbers restricted to 2 000 head until the viability of the ranch is established. Area not less than 2 000 ha per 1 000 head of cattle, with 1 200 ha for wet season and early dry season grazing and 800 ha for fodder grass to provide additional dry season roughage. Supplementary dry season feeding by cottonseed, cottonseed cake, groundnut cake, brewers grains or molasses as available. Limited to sparsely cultivated areas. 5. Cattle ranches and dairy farming Establishment of dairy herds of not more than 100 milking cows. Total area not less than 250 ha, with 130 ha improved pastures for wet and dry season grazing and 50 ha to provide additional dry season feed, supplemented by locally available concentrates and crop residues. Development financed and managed by Government and covering a few to 100 ha in one location, usually for sawn timber production for 6. Development for pro local use, alternatively by a commercial company at minimum annual planting rate of 400 ha for sawn timber or pulp. Confined to duction of timber forest reserves. 6/7. Production (a) Production by State and Federal Departments in forest reserves. 7« Development for forestry production of firewood and (b) Production by farmers on small woodlots, backed by extension service. poles (c) Extraction from areas of natural vegetation in forest reserves. Protection of existing and establishment of new forest reserves in areas with slopes greater than 10$ (6°) where conservation is 8. Protection forestry, reservation to required. protect areas against erosion or strict conser\ratio n resourced Protection required only in parts of area. TABLE 33 Agricultural development possibilities in relation to administrative units and land systems in the Bauc^ii Plains Land systems suitable for different types of development 7*. Firewood and poles production from Administrative 1. Integrated agriculture unit 2. Mechanised 3. Traditional 4. Grazing 5. Cattle ranches 8. Protection (a) Forest reserves farming grazing reserve and dairy farming (b) Farmers (c) Natural forestry (a) In densely (b) In sparsely wood lots vegetation cultivated areas cultivated areas Name LS Bauchi State Hisau LS22,25,26 LS25 LS25 LS25 LS22,25,26, All LS (2)/ (0,(2) except 30 Shira LS22 LS22 LS22.19 Kurba LS 20 LS22 All LS (2) I (0 except 30 Darazo LS17,18,25 LS17,18,20,25 LS17,18,20,25 LS8,14,15,17, 1^8,14,15,17, LS15,17,18,20,25 Farin Ruwa LS8.13 All LS LS1,2,8,15,17, (0,(2),(5) (1¥2«5«8) (0,(2),(5),(8) 18,19,20,25 18,19120,25 (1«2)j(5«13) Kuna Hill LS8 18,23 (l),(2),b), 0,(1),(5), Sumu LS15 (13) Zala LS8,13,15 (55 Zalanga LS8 Alkalere LS8,24,27,28, LS8,24,27,28, LS27,28,30 Dutsen All LS LS1,2,10,13, LS8,13,14 30 (0/2),(13) Bello except 29 23,32 (0,(2),(13) (0,(2), (13) (24) Bauchi LS7,8,14,15, LS7,8,14,15, LS14,15,27,28 Buli Hill LS7 All LS LS1,2,13, 27,28 27,28 (0,(2),(5),(9),(13) Kir Hill LS8.28 except 29 (7) Ran LS7.8 Tala Hill LS13 Bass LS12.14.27, LS12.14.27, LS14,27,28,34 All LS LS1,12,13,28, 28,34 28,34 (1«5«12) 32,33 (0/5)/12) (l«5«1t),(12) (5J Tafawa LS8,10,31 LS8,10,14,27, LS8,10„14,27, LS14,27,28,30, LS3,8,27, All LS LS1,2,8,12,13, Balewa (0,(25 28,30,31 28,30,31 29,36 except 29 27,32,36,37 (1)/2),(5),(13) (1^(25/5 «13) (1),(2«5W9)1(13) (1«2M13) (5)/27) Ningi LS15.16.21 LS15,1^,21 LS15,16,21 All LS LS1,2,11,21 (0,(2),(5), (0,(25,(5), (0,(2), (5), (11), (10,(13) (10,(13) (135 iili S Toro LS4,34,36 LS6,7,8,12, LS6,7,8,12, LS7.15 LS8,11,13 LS4,6,34, All LS LS1,2,3,8,11, (5),(6},(13) 15,16 15,16 : (1W2)*5)*H)*12) LS3,36 except 4, 13,15,16,32 (0,(2),(5), (lj,(2),(5), LS3,8 (1«5«13) 34,35,36 (5W6/14W36)- (10,(12) (10,(12) LS8.11 LS3 * There is nö forestry suitable for timber production in the Bauchi Plains / Land systems shown in brackets occur as small pockets within the land systems recommended for development. With the exception of the floodplain areas (Land System 5) these small pockets of land are not suitable for agricultural development possibilities of Types 1-6. TABLE 33 Agricultural development possibilities in relation to administrative units and land systems in the Bauchi Plains (cont'd) Land systems suitable for different types of development 7*. Firewood and poles producl ;ion from Administrative 1. Integrated agriculture unit 2. Mechanised 3. Traditional 4« Grazing 5. Cattle ranches 8. Protection (a) Forest reserves grazing reserve and dairy farming (b) Farmers (c) Natural fore;; try (a) In densely (b) In sparsely farming wood lots vegetation cultivated areas cultivated areas Name LS Plateau State Kanam LS12,27,28, LS12,27,28, LS28.30.31 All LS LS1,2,10,12, 30.31 30,31 (0,(2),(5) 13,23,24,30, (1),(2),(5) (1),(2),(5) 32,39 Pankshin (LS29) LS3.10 LS3.10 LS3,10 LS29 All LS LS10.32 (1),(2),(32) (1l(2),(32) (1),(2),(32) (1) Mangu LS8,35 LS3,8,35 All LS LS1,2,36 (2),(13) (2)/13) except 4, 34,35,36 Jos LS4,34,35 LS35 LS4.35 All LS LS1.2 (2),(5),(13) (2«3),(13) (2)/5),(13) except 4, 34,35,36 Barakin LS3 All LS Ladi (2) except 4, 34,35,36 Kano State Birnin Kudu LS25 LS 20 LS 20 LS19,20 LS19.20- LS20 All LS (2),(13) (2W13) (2),(5),(13) (2), (5),(13) (2),(5),(13) except 30 * There is no forestry suitable for timber production in the Bauchi Plains / Land systems shown in brackets occur as small pockets within the land systems recommended for development. With the exception of the floodplain areas (Land System 5) these small pockets of land are not suitable for agricultural development possibilities of Types 1-6. TABLE 34 Land systemswith few limitations to the growth of particular crops, in relation to administrative units Land systems with few limitations to particular crops Administrative unit Maize Millet Sorghum Groundnut Cotton Bauchi State Misau LS26 LS26 LS26 Shira LS22 LS22 LS22 Darazo LS17 LS8,17,18,20,25 LS8,17,18,20,25 LS8,17,18,20,25 Ningi LS9 LS9 LS9 LS9 LS9 Toro LS9,34 LS4,8,9,36 LS4,8,9,27,34, LS4,8,9,27,36 LS9,34 36 Bauchi LS8,10,25 LS8,10,25,27 LS8,10,25,27,28 Alkalere LS8,10 LS8,10,25,27 LS8,10,25,27,28, 30,36 Tafawa Balewa LS9 LS8,9,31,36 LS8,9,27,31,36 LS8,9,27,28,29, LS9 30,31 Dass LS9,34 LS8,9,10 LS8,9,10,27,34 LS8,9,10,27,28 LS9,34 34 Kano State Birnin Kudu LS20,25 LS20,25 LS20,25 Plateau State Jos LS 34 LS35,36 LS34,35,36 LS35,36 LS 34 Bassa LS4 LS4 LS4 Mangu LS8,35,36 LS8,35,36 LS8,35,36 Pankshin LS10 LS10 LS10,29 Kanam LS10,31,36 LS10,31,36 LS10,27,28,30, 31,36 All areas LS9,17, LS4,8,9,10,17, LS4,8,9,10,17, LS4,8,9,10,17, LS9,34 34 18,20,22,25,26, 18,20,22,25, 18,20,22,25,26, 31,35,36 26,27,31,34, 27,28,29,30, 35,36 31,34,35,36 79 1. INTEGRATED AGRICULTURAL DEVELOPMENT PROJECTS An integrated agricultural development project involves the concentration of agricultural, medical and educational resources in selected areas with associated improvement in communications. In this report only the agricultural aspects of such a project are discussed, it must be emphasised that these aspects cannot be considered in isolation, as successful development is dependent on improvements in the whole range of rural services. These projects can be established either in intensively cultivated areas or in areas where there is room for the expansion of the area under cultivation. The structure of the project can be similar in both cases, but, in the former, any increase in agricultural production must come from increased yields and intensification of the present farming system. Such projects should be administered by a semi-autonomous project authority and involve the improvement of infrastructures, concentration of extension services and creation of farmers' organisations. They also include some degree of mechanisation, supply of agricultural inputs,- provision of credit and marketing arrangements, as well as associated services such as water supply and health. Obviously, project proposals must be fully explained to the local population and located only where their full co-operation is ensured. These factors are discussed below. Project authority A semi-autonomous project authority should be established to co-ordinate and implement all aspects of the development programme. It should include local farmer representation from the beginning and have the long-term objective of becoming entirely run by local people with government advice. 80 TABLE 34A Criteria used to assess the suitability of an area for particular types of agricultural development Type of Rock or Cultivation Minimum Crop Slope Trypanosomias is agricultural Gullying ironpan density size of Other factors options % hazard development outcrops % . unit,ha* 1. Integrated agricul tural development Nil to Nil to (p.80) a. 3 + <10 slight few - , >35 - - b. 3 + < 10 < 35 2. Mechanised farming 3 + < 3 Nil to Nil to - <35 1 000 Not unduly fragmented by (p.86) slight few drainage lines 3. Traditional grazing Nil to . (p.89) ' mod. if <10 protected Nil to slight < 35 mm 4. Grazing reserves - <10 ii - tl M - - (p.92) 5. Cattle ranches ^. <10 Nil to Nil to slight < 35 1 ooo (p.94) slight - Dairy farms <10 II II < 35 16o (p. 94) " - 6. Production of timber 5-100 Limitations due to edaphic (p.98) • factors.Gazetted forest reserves 7. Production of a. II II n firewood and b. - - - - - >35 poles (p.98) c. <35 i 8. Protection • forestry - ->10 - . - - - - - : o (p.102) *The minimum size of unit has been justified in the report but, for cartographic reasons, the smallest area shown on the map is approximately 1 500 ha. ————-—— Infrastructure Roads, water supplies, marketing and storage facilities should be provided before the full scale injection of agricultural inputs, though some inputs should be made available to establish credibility with the farming community. Staffing Trained and experienced extension staff should be located in the villages. Initially the ratio of extension staff to farming families should not exceed 1:500, but once new techniques have been accepted the ratio can be increased and extension staff made available for similar projects elsewhere, or the expansion of the project area itself; Size of holding The farm should be large enough to enable the farmer to make a minimum income that will counteract the attraction of moving to an urban area. Mansfield (in press) has suggested that this requires a minimum net annual income of about S 900. Norman (1972) has shown that most farmers derive about 22% of their total income from off-farm activities during the dry season,so farmers would have to derive about »740net from the farm. The minimum size of holding needed to produce an income of » 740 has been calculated using data from IAR socio-economic studies. The size of holding has been calculated for farms using hand labour only; for farms using family labour and two draught oxen; and for farms using family labour, oxen and herbicides. Maize, sorghum, groundnuts, cowpeas and cotton have been considered as the main crops. The choice of crop is dependent on which gives the maxiumum net return per unit area. The various farm sizes are given in Appendix 3 and more details of the calculations are by Mansfield (in press). The figures show that the minimum size of holdings using only hand labour range from 5.5-7.5 ha (13.8-18.5) ac): this includes some fallow and assumes the farmer hires labour additional to the family input equivalent to seven adults. Holdings using oxen must be much larger. In practice actual farm sizes will be even larger than these theoretically calculated sizes as the farmer does not grow single cash crops. Although the farm sizes are calculated using data collected in the Zaria area and details may differ for the Bauchi Plains, the size of holding is unlikely to be significantly lower. Consequently in many of the densely cultivated 81 areas of the Bauchi Plains that have a high population there is not enough land for each farmer to have a holding big enough to generate an income equal to that earned by many daily paid government employees. Oxenisation Throughout Nigeria the term 'mixed farming' describes the use of animals for draught and this has usually been restricted to ploughing or ridging. Mixed farming has always been envisaged as the integration of crop and animal husbandry involving the feeding of crop residues, the cultivation of fodder crops, the use of manure and the use of animals for a variety of draught purposes. Implements for cultivating and planting and carts are available; the best equipment is simple to adjust and can be maintained by village blacksmiths. In areas where the cultivation density is less than 35% and spare land for larger holdings is available, an improved system based on a 10-12 ha (25-30 acre) farm size enables the bulk of the bulls' food to be produced on the farm. Mechanisation with tractors To make the use of tractors economic, they must be used for most of the farming year. This means that most farming operations need to be mechanised and this necessitates clean stumping, with an associated increase in the risk of erosion. Farms must also be organised into large blocks. All this involves a complete change in the farming system, and experience in othe: areas shows that the farmer becomes less involved and less enthusiastic. Full mechanisation is therefore more appropriate to large mechanised farms. If tractors are used primarily for land preparation to eliminate the drudgery of hand cultivation and to enable planting to take place earlier, then it is unlikely that the tractors can be operated economically. Even if farms are organised into blocks, the tractors will remain idle for a large part of the year, together with the drivers and maintenance staff. A government subsidy of the service is essential. More efficient use of equipment might be achieved by commercial contractors who use the tractors for other work during the rest of the year. If mechanisation of cultivation is 52 undertaken(erosion control measures are necessary in areas with slopes greater than 1%. The full benefits of the mechanisation will not be obtained unless other inputs are made available at the same time. Credit and marketing Seasonal loans should be provided to enable farmers to obtain improved seed, fertiliser, agricultural chemicals, equipment and tractor hire services. Marketing of scheduled crops should be controlled by the project authority and loans recovered from the value of the cotton. With crops that can be marketed locally, loan recovery is more difficult. It may depend on refusing further credit and services to debt defaulters and by making bad debts a community responsibility. Other agricultural inputs Inputs such as fertilisers, herbicides, pesticides, implements, improved seed and planting material should be available to the farmers at the correct time. Credit may be necessary so supplies should be available where crops are marketed. Implementation schedule As it is unlikely that the whole area could be developed at once, development should be phased to keep pace with the build-up of staff and infrastructure. After the initial establishment of the Project Authority, each phase should be scheduled as follows: Year 1 i Recruiting and training of new staff and orientation courses for existing staff at agricultural centres. ii Provision of a limited supply of inputs to establish credibility with the farming community. iii Intensive publicity and formation of farmers1 groups, followed by their involvement in development of infrastructural needs, including roads, housing and water supplies, as well as the establishment of soil and water conservation works. Assistance would be given in such matters as materials, bridge and culvert construction, road alignment and technical advice on layout and design. 83 iv The establishment of seed multiplication units for an initial period until these can be run by the farmers. Year 2 i Continuation of publicity and formation of farmers' groups. ii Extension staff move to their villages and start work on demonstration plots. These are possibly sited on their own farms (for which they are solely responsible) and on which they carry out the manual work involved with assistance from their family. These are to act as a practical demonstration to the farmers and would help the extension staff to build up cheir standing within the farming community. iii Continuation of the build-up of the infrastructure, with the population involved at all stages, concentrating on the building of storage facilities and mechanical workshop for mechanisation. iv Establishment of distribution, marketing and credit organisation. The ordering and delivery of all agricultural inputs required for Year 3. Year 3 The project becomes fully operational» All the required inputs are available to farmers, through their group organisations, together with extension advice on the way to use them. Location of integrated agricultural development projects in the Bauchi Plains Only area with three or more crop options have been considered suitable for the establishment of integrated agricultural development projects as a choice of crops is considered essential. Suitable areas occur in the Tafawa Balewa, Darazo, Misau, Toro, Pankshin, Mangu, Jos and Barakin Ladi Local Government Areas. The location of these areas is shown on Text Map 1.3, and on Separate Map 4 and is given in Table 35 in relation to administrative units and land systems. 34 BAUCHI PLAINS TEXT MAP 1.3 AREAS SUITABLE FOR INTEGRATED AGRICULTURAL DEVELOPMENT PROJECTS (based on environmental and present land use factors only) lO'OO' East of Greenwich C . —J Scale 1:1.000.000 Kilometres 10 5 O 10 20 30 Kilometres Boundary of Bauchl Plains Miles 10 5 10 20 Miles D.O.S. 3250 C Prepared by the Directorate of Overseas Surveys 1977 TABLE 35 Location of integrated agricultural development projects in the Bauchi Plains Land systems suitable for integrated agricultural development projects Administrative units 1 Densely cultivated j Sparsely cultivated areas j areas j Bauchi State i Darazo 17, 18, 25 17, 18, 20, 25 | d) , (2) , (5) (1) , (2) , (5) 8 Misau 22, 25, 26 25 (2) Shira 22 22 (2) Tafawa Balewa 8, 10, 31 (1), (2) Toro 4, 34, 36 (5), (6), (13) Plateau State Barakin Ladi Jos 4, 34, 35 35 (2), (5), (13) (2) , (13) Mangu 8, 35 (2), (13) Kano State Birnin Kadu 25 20 (2), (13) Land system numbers in brackets refer to small pockets unsuitable for this type of development but within the generalised area on the map Of the possible locations shown in Table 35, Land System 17 to the west of Miya in the Darazo Local Government Area has few climatic or soil limitations to the growth of maize, millet, sorghum and groundnuts; there is also little erosion hazard and there are 291 km^ (112 mi2) of uncultivated or only sparsely cultivated land. The population is already familiar with mixed farming, an extension worker is based in Miya and a main road runs through the area. To the east of Miya, Land Systems 18, 20 and 25 have three crop options, millet, sorghum and groundnuts, but slopes are steeper and conservation measures must be established before any intensification of cultivation. There are few environmental limitations to the establishment of integrated development projects in the intensively cultivated areas of Misau and Toro Local Government Areas, but there is little room for expanding the area under cultivation. 85 Effect on other types of development The establishment of an integrated development project can mean an increase in the area under cultivation and a reduction in the area available for grazing. However, there will be an increase in crop residues and if these are made available to'cattle, they should offset the loss of dry season grazing. The increase in cultivation does mean a loss of wet-season grazing, but in the Bauchi Plains there is still a considerable area of uncultivated land available for grazing in the wet season. If the intensity of cultivation is increased over a large area, the provision of firewood and poles may create difficulties. Plantations may need to be established or farmers encouraged to grow woodlots to meet demand. 2. LARGE MECHANISED FARMS FOR PRODUCTION OF RAINFED ANNUAL CROPS In Nigeria these farms have been established by government for the production of large quantities of food crops or as seed multiplication centres. Consideration is also being given to fibre production. Such projects should fulfill the following requirements: Size The farm should be at least 1 000 ha (2 480 acres) which is considered the minimum size for fully mechanised production of annual rainfed crops, based on experienced local opinion. This figure is an arbitrary one and a detailed economic analysis would give a more realistic figure. Site Density of existing cultivation should be less than 35% so that major problems of resettlement and compensation will not arise. Slopes should be less than 3%. Slopes greater than 3% require complex conservation layouts with horizontal intervals less than 50 m (150 ft) resulting in inefficient working of machinery due to short runs and excessive turning time. 86 Soils Detailed soils information is necessary together with a contour map. Soil and water conservation works The basic layout of field access roads, storm drains, terraces and grassed waterways should be established before cultivation commences. Shelter belts should be planted up as soon as possible. Dams and weirs should be constructed at this stage as required. Machinery and equipment The types and quantity of machinery and equipment should be selected to suit both local conditions and the crops to be grown. Adequate spares together with repair and maintenance facilities should be available on site. Buildings These should include adequate cleaning and storage facilities for the crops qrcwn, as well as provision for bulk handling. Drying plants may be necessary in certain cases. Management Due to the high capital investment in such schemes, it cannot be over-emphasised that experienced and highly skilled management is a key factor in their success. Implications of mechanised schemes The aim of these schemes should not be to compete with the local farms for crop markets or to result in lower prices to the producers. Their main justification is to build up national food reserves speedily and/or boost improved seed production, and as such must be linked with central storage facilities. Where suitable areas are restricted, the establishment of large mechanised farms may compete with grazing, forestry and fallow land requirements. 87 At present, such schemes are being initiated on an ad hoc basis without adequate information on the following aspects: Economic viability Their relationship to schemes being initiated elsewhere Their effect on overall crop production, marketing and prices The long-term effects of intensive mechanised agriculture on soils which are often infertile and poorly structured Rotations Possibilities of integration of livestock enterprises with crop production Location of large mechanised farms in the Bauchi Plains Suitable sites for the establishment of such farms occur only in the Darazo Local Government Area. They are shown on Text Map 1.4 and on Separate Map 4. Land System 17? to the west of Miya, has few environmental limitations to the growth of maize, millet, sorghum and groundnuts. Slopes are gentle and there is little erosion hazard though frequent small rock outcrops might be limiting to machinery. , There is plenty of uncultivated or only sparsely cultivated land and a main road runs through the area. Suitable sites also occur in Land Systems 18, 20 and 25 to the west of Miya,but as slopes are steeper,conservation works would be necessary. Rock outcrops and actively eroding stream banks would also be limiting in parts of these land systems. Scheme sizes of 1 000-2 OOO ha are most suited to tl.e drainage density and pattern in these units, the former giving the greacer flexibility in layout. Other sites in the Bauchi Plains have been dismissed as unsuitable because they are presently intensively used, the slopes are too steep or there are soil limitations to the growth of the crops considered. Effect on other types of development The establishment of large mechanised farms means a reduction in the area of the land for grazing. Unless specific plans are made for their ur-e„it is unlikely that crop residues would be available for cattle as under intensive mechanised agriculture most of the stubble would either be burnt off or ploughed in with the addition of nitrogenous fertiliser. Mechanised schemes would preclude any 88 BAUCH I PLAINS TEXT MAP 1.4 AREAS SUITABLE FOR LARGE MECHANISED FARMS (based on environmental and present land use factors only) 8*50- 9W O'OO' East of Greenwich 11-30 f- C . —> Scale 1:1.000.000 Kilometres 10 5 O 10 20 30 Kilometres Boundary of Bauchl Plaint Miles 10 5 20 Miles D.O.S. 3250 D Prepared by the Directorate of Overseas Surveys 1977 form of production forestry but there would be a need to establish windbreaks and shelterbelts. The effect that the production from large mechanised farms would have on local market prices is unknown at present and needs study. If the objective is to build up strategic food reserves then they are unlikely to compete directly with the farmer. 3. IMPROVEMENT OF TRADITIONAL GRAZING Traditional grazing involves the use of uncultivated land, fallow land and crop residues by nomadic or semi-nomadic herds of cattle. Herds of cattle belonging to settled and nomadic owners graze uncultivated upland areas during the wet season; in the dry season they utilise crop residue stubbles and floodplains. Settled pastoralists and cultivators owning cattle will herd them within a short distance of the village or permanent camp site. Other pastoralists herd their cattle over a larger area moving camp and kraal at frequent (5-15 days) intervals. In the dry season some herds will move a .distance of lOO km or less, but for many the seasonal search for grazing may involve a trek of 500 km. Due to increasing cultivation, there is an increasing pressure on the fodder resources. Uncontrolled burning and grazing of the subsequent flush of new shoots and the excessive lopping of fodder trees is leading to a gradual deterioration in the productivity of the rangeland. The cooperation of the pastoralist is essential to any attempt to halt or reverse the deterioration of the rangeland; improvement must involve the control of stock numbers and stock movement. The pastoralists' dislike of interference and his suspicion of authority will make this cooperation difficult to secure. Ideally their concern for their stock must be extended to include a concern for the environment and its resources; it is difficult to understand their apparent present indifference to ensuring the sustained productivity of the rangeland. To encourage a change in attitude it may be necessary to allocate grazing rights to particular groups of pastoralists. 89 Among the measures which are necessary in any attempt to improve rangeland are: 1„ The education of the general public as well as the pastoralists about the harmful effects of bush fires during the dry season 2„ The preservation of fodder trees by demonstrating that less severe lopping provides a greater yield óf fodder in subsequent years. 3. Pasture improvement. The introduction of legumes, particularly Stylosanthes into the natural grassland would provide valuable herbage in the dry season. However, the problems of establishing legumes over large areas are considerable: these are problems of seed supply, the question of who would be responsible for planting and the control of stock including small ruminants. 4o The improvement should form part of a coordinated inter-State policy which includes the creation of grazing reserves discussed in the 'next section. Areas for improvement of traditional grazing The areas where the improvement of traditional grazing should be most effective are shown in Table 36 in relation to land systems and administrative units. They are also shown on Text Map 1.5 and on Separate Map 4„ 90 BAUCHI PLAINS TEXT MAP 1.5 AREAS SUITABLE FOR IMPROVEMENT OF TRADITIONAL GRAZING (based on environmental and present land use factors only) O'OO' East of Greenwich 9*00' East of Greenw.ch I ( C . * Scale 1:1.000.000 Kilometres 10 5 0 10 20 30 Kilometres Boundary of Baucht Plains Miles 10 5 D.O.S. 3250E Prepared by the Directorate of Overseas Surveys 1977 TABLE 36 Areas for improvement of traditional grazing in the Bauchi Plains Land system In small pockets within Administrative unit Suitable for improvement generalised area on the of traditional grazing map but not suitable for proposed development Bauchi State Misau 25 Alkalere 27,28,30,8,24 1,13,2 Bauchi 14,15,27,28, 7, 8 2,5,1,13 Darazo 15,17,18,19,20,25,8,14 1,2,5,13 Dass 14,27,28,34,12 1,5,12 Ningi 15,16,21 1,2,13,5,11 Tafawa Balewa 8,14,127,28,30,31,10 1,2,9,13,5 Toro 7,15,6,8,12,16 1,2,5,11,12 Shira 19.22 Plateau State Kanam 28,30,31,12,27 2,1,5 Pankshin 3,10 1,32,2 Kano State Birnin Kudu 20,19 2,13,5 Note: Double entry of 12 is correct - land use affected by cultivation intensity Effects on other types of development Traditional grazing may be improved without major changes to other existing agricultural activities, but it should be planned in relation to them. Most immediately, policies of pasture improvement in forest reserves need co ordination with forestry departments. It is an obvious but important fact that an increase in the area of land used for, say, arable cropping, means a decrease in the area available for grazing, though this may be partially offset by the increased availability of crop residues. Where an expansion of the area of cultivated land is planned or is actually taking place, the improvement of traditional grazing is particularly urgent. In such areas, there will eventually be insufficient land to support pastoralism as presently practiced and provision should be made for the establishment of managed grazing reserves. The tsetse eradication programme is making additional land available for grazing. 91 4. ESTABLISHMENT OF GRAZING RESERVES The Grazing Reserve Law 1965 provides for the establishment of grazing reserves to achieve ultimately the settlement of nomadic pastoralists. Because the needs of his stock in terms of food and health have necessitated the pastoralists seasonal migration, the establishment of grazing reserves should initially aim at modifying the existing pattern of transhumance rather than its elimination. This would involve: 1. The establishment of an inter-State body to coordinate policy as it cannot be undertaken in isolation 2. Main wet (home) and dry season grazing areas should be demarcated and gazetted as grazing reserves: Bauchi* is a wet season "home" area for cattle that spend the dry season in the Keffi/Abuja area. Settled and semi-nomadic herds could also be accommodated in these reserves 3. Grazing reserves should be established along the main migration routes to act as staging posts for the nomadic herds. They should have fencing, adequate water supplies and veterinary facilities to make them attractive to the Fulani. The aim of these staging posts should be to regulate and facilitate transhumance 4. The natural grassland within the grazing reserves should be improved by i. An intensive campaign to make the nomadic Fulani aware of the long term dangers to dry season burning and the indiscriminate lopping of fodder trees ii. Selective reduction in the shrub vegetation iii. The introduction of grass and legume species, by sod- • seeding (minimal cultivation) These measures will only be effective if it can be demonstrated to the Fulani that their cattle will be better off than with their traditional way of life. Disease may initially be a problem following settlement. *Bauchi is also a dry season area for cattle coming from Bornu to utilise crop residues 92 Location of grazing reserves in the Bauchi Plains Areas suitable for the establishment of grazing reserves occur in all the Local Government Areas except Misau and Shira. The location of these areas is shown on Text Map 1.6 on Separate Map 4 and is given in Table 37 in relation to administrative units and land systems. They can be most easily established in areas of low cultivation which can be identified on Separate Map 2. TABLE 37 Location of grazing reserves in the Bauchi Plains Land system In small pockets within Administrative unit Suitable for generalised area on map grazing reserves but not suitable for proposed development Bauchi State Alkalere 8,24,27,28,30 1,2,13 Bauchi 7,8,14,15,27,28 1,2,5,9,13 Darazo 8,14,15,17,18,19,20,25 1,2,5,13 Dass 12,14,27,28,34 1,5,11,12 Misau 25 Ningi 15,16,21 1,2,5,11,13 Tafawa Balewa 8,10,14,27,28,30,31 1,2,5,13 Toro 6,7,8,12,15,16 1,2,5,11,12 Shira 19.22 Plateau State Kanam 12,27,28,30,31 1,2,5 Pankshin 3,10 1,2,32 Kano State Birnin Kudu 19,20 2,5,13 . Note: Double entry of 12 is correct - land use affected by cultivation intensity Effects on other types of development The establishment of grazing reserves reduces the land available for cultivation and forestry. It does not necessarily mean that the cattle population can be increased by the numbers accommodated in the reserve. 93 5. ESTABLISHMENT OF CATTLE RANCHES AND DAIRY FARMS Livestock enterprises which include growing out* ranges and dairy farms require high standards of management; the exotic breeds which are recommended for milk production are particularly demanding and successful dairy farming largely depends on the skill of the stockmen. The major problem in the Bauchi Plains is the provision of adequate feed in the dry season and it is envisaged that both types of enterprise will rely heavily on crop-processing or food manufacturing by-products. In addition the more'exacting food requirements of the milking cow involve the provision of good quality bulk food; this requirement is probably most satisfactorily met by the cultivation and conservation of suitable crops as silage. It cannot be over-emphasised that the economics of livestock enterprises require the most careful investigation. Cattle ranches The ranches will "grow out"* over a period of 5-10 months semi-mature cattle purchased from Fulani herds. (in several African countries government ranches provide grazing and veterinary care for cattle which remain the property of the owners who pay a monthly fee: the cattle must go to slaughter after six to eighteen months.) Herd size The number of cattle on the ranch will fluctuate but should not exceed 2 OOO until experience has been gained and the economic viability of ranching has been established. Stock should be purchased mainly in the second half of the dry season; there should be a regular off-take of cattle for slaughter and numbers would be at a minimum prior to the main purchasing period. *The proposed system cannot be termed 'fattening' but growth and weight increase is implied. 94 BAUCHI PLAINS TEXT MAP 1.6 AREAS SUITABLE FOR ESTABLISHMENT OF GRAZING RESERVES (based on environmental and present land use factors only) 10*00' East of Greenwich 9'00' East of Greenwich I ( V. . * Scale 1:1.000.000 Kilometres 10 5 0 10 20 30 Kilometres Boundary of Bauchi Plains Miles 10 5 20 Miles D.O.S. 3250 F Prepared by the Directorate of Overseas Surveys 1977 Wet season feeding Natural grassland should provide satisfactory grazing for the 'first' three months of the wet season (commencing about 3/4 weeks after the first rains). Improvement of the grassland by the introduction of Stylosanthes guyanensis will extend the period during which grazing alone is satisfactory by two to three months, exceptionally a little longer. Dry season feeding Natural grassland only provides poor quality roughage, and if there is not to be very heavy dependence on supplementary feedstuffs such as cotton seed, cotton seed cake, brewers grains or groundnut cake, it will be necessary to provide suitable fodder. Stands of either guinea grass (Panicum maximum) and elephant grass (Pennisetum purpureum) could be cultivated and during the dry season cut daily and mechanically chopped before feeding. Area of ranch The area of a ranch for a unit of 1 000 head is given in Table 38; the number of cattle will be lower during certain periods of the year. TABLE 38 Cattle ranch area per 1 OOO head (7 kg (15 lb) D.M. intake per head per day) Yield Area Category t/ha tons/ac ha ac Wet season grazing 1 200 2 965 Dry season fodder 10* 4* 800 1 977 Buildings, yards, crushes, etc. 70 173 Total 2 070 5 115 *Green material It may be found profitable to fatten suitable animals for 3-4 months prior to slaughter; it is anticipated that the costs of this practice will limit it to small numbers of animals which would attract a premium at slaughter. 95 Dairy farms Herd size Because of the lack of commercial dairy farm operating experience, . it is recommended that farms be initially restricted to lOO milking cows, which with herd replacement corresponds to 160 livestock units. Breed The herd should consist of Friesians which have been kept successfully under similar climatic conditions at Shika, Zaria. They should yield approximately 2 270 kg (5 000 lb) per lactation compared with Bunaji (White Fulani) 910 kg (2 000 lb) and cross bred Bunaji-Friesian 1 640 kg (3 600 lb). Wet season feeding Pastures improved by sowing with Stylosanthes spp., should should provide maintenance for mature and semi-mature stock. Milk production should be based on concentrate feeding; small amounts of concentrates should also be fed to calvers and to young stock in the second half of the wet season. Unimproved grassland can be discounted as a source of nutrients for dairy cows after the first half of the wet season. Dry season feeding Silage should be fed generously (adult cattle eat approximately 8-9 kg (18-20 lb) of dry matter per day). Good quality hay is useful for calves and also for sick animals; if it is not possible to purchase leafy cowpea haulms or.harawa (groundnut haulms) a legume such as Glycim j-aVani-ca or Stizolobiüm deeringianum may be grown and conserved as hay. Natural grassland does not make satisfactory silage (Miller et al., 1963) and it is desirable to ensile a purpose-grown cereal crop such as maize or sorghum. These crops must be ensiled during the late flowering stage. Timely harvesting of a large area may be difficult and it is therefore recommended that trials of species such as elephant grass or guinea grass for ensiling be undertaken; the necessary additional silage would be made from the more suitable of these fodder grasses to which fertiliser would be applied. 96 Concentrates should be fed to milking cows according to yield, and to. immature stock. It is recommended that the concentrate ration be compounded on the farm from purchased materials. Changes in the formulation of concentrate or in the overall rations should always be introduced gradually. Area of farm The farm size required for 160 livestock units is given in Table 39. TABLE 39 Dairy farm: area per lOO cows plus followers Yield Area Category t/ha ton/ac ha ac Improved pasture 132 320 Legume hay 3.8* 1.5* 12 30 Cereal for silage 20 ** g ** 20 50 Fodder grass for silage 10 ** 4 ** 30 75 Building, yards 34 85 Total 228 560 *Dry matter, **Green material Location of cattle ranches or dairy farms in the Bauchi Plains Suitable*sites for the establishment of cattle ranches or dairy farms occurs in the Alkalere, Bauchi, BirninKudu, Darazo, Dass, Ningi and Tafawa Balewa Local Government Areas. The location of these within the Local Government Areas is shown on Text Map 1.7, on Separate Map 4 and is given in Table 40 in relation to land systems. Such schemes can be established most easily in areas of low cultivation intensity: these areas have been identified from Separate Map 2 and the location of suitable areas for ranches or cattle farms shown on Separate Map 4 For dairy farms it is essential that the site should include at least 60 ha (150 ac) of soils which.have few limitations for crop growth. •Accessibility and good roads to urban markets are essential for dairy farms. 97 TABLE 40 Location of cattle ranches or dairy farms in the Bauchi Plains Land system In small pockets within Administrative unit With suitable sites for generalised area on map cattle farms or ranches but not suitable for proposed developments Bauchi State Alkalere 27,28,30 1,2,13 Bauchi 14,15,27,28 1,2,5,9,13 Darazo 15,17,18,20,25 1,2,5,13 Dass 14,27,28,34 1,5,12 Misau 25 Ningi 15 ,16,21 1,2,5,11,13 Tafawa Balewa 14,27,28,30,31 1,2,5,9,13 Toro 7,15 1,2,5,11,12 Plateau State Kanam 28,30,31 1,2,5 Pankshin 3,10 1,32 Kano State Birnin Kudu 20 2,5,13 Effect on other types of development The establishment of cattle ranches or dairy farms reduces the area of land available for cultivation and forestry. The effect of production from these farms on local markets for meat and dairy products is not known, but it is likely that demand presently exceeds supply. 6. FORESTRY DEVELOPMENT FOR PRODUCTION OF TIMBER Environmental limitations in the Bauchi Plains, particularly climate, mean that that growth rates are low. Timber production has therefore not been considered. 7. FORESTRY DEVELOPMENT FOR PRODUCTION OF FIREWOOD AND POLES Firewood and poles can be produced by (a) State and Federal Departments in forest reserves } (b) farmers growing small woodlots, backed by a forestry extension service f (c) extraction from areas of natural vegetation. 98 BAUCHI PLAINS TEXT MAP 1.7 AREAS SUITABLE FOR CATTLE RANCHES OR DAIRY FARMS (based on environmental and present land use factors only) 0*00' East of Greenw.ch C . —•* Scale 1:1.000.000 Kilometres 10 5 O 10 20 30 Kilometres Boundary of Bauchl Plains I ^~ Miles 10 5 20 Miles D.O.S. 3250 G Prepared by the Directorate of Overseas Surveys 1977 7a. Production of firewood and poles by State and Federal Departments This type of forest production has the following characteristics 1. The plantation is financed and managed by Government 2. A few hectares to lOO ha (250 ac) are planted in one location 3. The production is usually directed towards meeting a local requirement for firewood and poles 4. The work has an element of research in it and so the costs are not critical. Alternatively the plantation is established for social reasons even though it is not economically viable. Location of areas for production of firewood and poles by State and Federal authorities Production takes place only within forest reserves so the growth potential of different species for which information is available within forest reserves is shown on Text Map 1.8, on Separate Map 4, and is given in Table 41 in relation to Administrative areas and land systems. The method of assessing the growth potential is given in Appendix 4. Effects on other types of development As production takes place within forest reserves the effect on other types of development is limited. 99 TABLE 41 Growth potential of Eucalyptus and neem in forest reserves in the Bauchi Plains Growth Administrative Forest Land system Species potential unit Reserve m3/ha/a Bauchi State Alkalere Dutsen Bello Eucalyptus 8 <2 it 13 <2 H 14 <2 Bauchi Buli Hill Eucalyptus 7 <2 Kir Hill 8, 28 <2 Ran ii 7, 8 <2 Tala Hill n 13 5 Darazo Farin Ruwa Neem 8, 13 <2 Kuna Hill H 8 <2 Sumu II 15 5 II O 1 ~» Zala u, x->, <2 H 15 5 Zalanga H 8 <2, Shira Kurba Neem 20 <2 Toro Jauro Eucalyptus 8, 11, 13, 5 II 15 io Maigama II 3, 36 5 Panshanu II 3, 8 5 Tatu II 8, 11 5 Wall Hill II 3 5 7b. Production of firewood, poles and economic farm trees by farmers The development of this type of forestry should include the following: 1. A forestry extension service should be formed,using Government and local authority field staff, to encourage the protection of farm trees and planting of indigenous and exotic trees. 100 BAUCHI PLAINS TEXT MAP 1.8 FOREST RESERVES FOR PRODUCTION OF FIREWOOD AND POLES, AND AREAS REQUIRING EXTENSION FORESTRY —' Scale 1:1.000.000 Kilometres 10 5 0 10 20 30 Kilometres Boundary of Bauchl Plains Miles 10 5 D.O.S. 3250 H Prepared by the Directorate of Overseas Surveys 1977 2 o Seedlings should be raised in a nursery and distributed to the farmers, who pay a subsidised price for them. 3. Equipment such a pig wire should be supplied to the farmer, possibly at a subsidised price to protect trees from goats. 4. The farmer should do the planting, weeding, fire tracing and felling, advised and encouraged by the forestry extension worker„ Location of areas for production of firewood, poles and economic farm trees by farmers This type of development is necessary in the densely cultivated area around Misau, Land Systems 22 and 26. It is also-necessary in Tafawa Balewa Local Government Area and in the south of Bauchi Local Government Area in Land System 29 and parts of Land Systems 27 and 28. In the Toro Local Government Area it is necessary in Land Systems 4, 34, 35 and 36. Effect on other types of development The production of firewood and poles by farmers becomes necessary whenever intense cultivation occurs over such large areas that farmers cannot collect firewood from nearby natural vegetation. It is therefore relevant to developments aimed at increasing the area of cultivation. The production of economic farm trees could be integrated with farming systems. 7c. Extraction of firewood and poles from natural vegetation There should be selective cutting of natural vegetation. Cutting of vegetation in forest reserves should be prohibited. Location of areas for production of firewood and poles from natural vegetation Areas of uncultivated land that can be used for firewood production occur in all the administrative units, with the exception of Misau Local Government Area. These uncultivated areas can be seen on Separate Map 2. 101 8. ESTABLISHMENT OF FOREST RESERVES FOR PROTECTION AGAINST EROSION Areas with slopes mainly in excess of 10% (6°) or which are severely gullied should be protected against erosion, either by the establishment of forest reserves or by strict conservation measures. Grazing should be prohibited until the forest reserves are well established and then strictly controlled so that the grass cover is not eliminated and the effectiveness of the erosion control reduced. If the areas are not reserved the strictest conservation measures must be enforced. Location of forest reserves for protection against erosion Areas requiring protection against erosion occur throughout the Bauchi Plains and are shown on Text Map 1-9, on Separate Map 4 and given in Table 42,.. in relation to administrative units and land systems. Most of the land systems are rocky, hilly areas but Land System 13 is severely gullied land around incised rivers. TABLE 42 Areas requiring protection against erosion in the Bauchi Plains Land system Administrative In small pockets within unit Requiring protection generalised area on map against erosion and not requiring protection ! Bauchi State Alkalere 1/ 2, 10, 13, 23, 32 part 24 I Bauchi 'If 2, 13 7 Dara z o 1, 2, 8, 15, 17, 18, 23 5 ' Dass I» 2, 12, 13, 28, 32, 33 5 Ningi If 2, 11, 21 - Tafawa Balewa If 2, 8, 12, 13, 27, 32, 36, 37 5 Toro If 2, 3, 8, 11, 13r 15, 16, 32 5, 6, 14, 36 Plateau State If 2, lO, 12, 13, 23, 24, 30, Kanam 32 ,39 - Pankshin If 10, 32 - Mangu If 2, 36 - Jos I, 2 - 102 BAUCHI PLAINS TEXT MAP 1.9 AREAS REQUIRING RESERVATION OR STRICT CONSERVATION 9"00' East of Greenwich I f l_.——J Scale 1:1.000.000 Kilometres 10 5 O 10 20 30 Kilometres Boundary of Bauchl Plains Miles 10 5 20 Miles D.O.S. 3250 J Prepared by the Directorate of Overseas Surveys 1977 CONSTRAINTS ON AGRICULTURAL DEVELOPMENT The Third National Development hlan, 1975-80, discusses the constraints on agricultural development as follows: "The constraints are several but the most serious are i. Shortage of qualified manpower in key areas ii. Inadequate supplies of agricultural inputs iii Inadequate extension service iv. The poor condition of feeder roads and other transport facilities .: ; v. Inadequate or lack of effective supporting services such as farm credit, marketing facilities, etc vi. The problem of land ownership imposed by the land tenure system in most parts of the country vii . The problem of diseases and pests viii The problem posed by labour shortage in the rural, areas in consequence of rural—urban migration < ix lack of appropriate or complete packages of technology for many food crops x Drudgery in farm work and low returns from agriculture which forces rural youth to migrate to.urban areas rather than go into farming1.' Interviews with 200 farmers in 13 villages scattered throughout the Bauchi Area (see Separate Map 2) confirmed that these factors are indeed constraints to agricultural development. Those factors for which data are available are discussed below and more fully by Gosden (1978). i. Shortage of qualified manpower in key areas and iii. Inadequate extension services 1. The ratio of field agricultural extension workers to farming families ranges from 1:10 600 to 1:2 200 within the administrative units in the Bauchi Area. Taken in conjunction with poor communications and lack of transport available to the extension worker, these high ratios mean that a large proportion of the farming population has little or no contact with advisory services. FA0 suggest that a ratio of one extension worker to 1 000 farming families is an absolute minimum and existing integrated rural 103 development projects in Nigeria are aiming at a ratio of 1:400. 2. ™here are only two staff directly concerned with range management in the Bauchi Plains, one stationed in Bauchi Town and one at Ningi. Veterinary assistants are responsible for animal health rather than range management and consequently there is very little extension work on grassland improve ment. 3. Professional forestry staff in Bauchi and their field assistants are mainly concerned with development of plantations and reserves. They are supported by a considerable number of forest guards in the local authorities. Laok of staff will be a constraint to the development of an extension service intendi to encourage farmers to grow woodlots. 4. With any extension service, whether it be for crop production, grassland improvement, or forestry, there is a conflict between the need to encourage and advise the population and the need for policing to eliminate mal practices. The two functions should be kept entirely separate and policing done by special inspectors. iv. The.poor condition of feeder roads and other transport facilities Reference to the legend of Separate Map 1 shows the length of main road, secondary roads and tracks in each land system in the Bauchi Plains though these figures must be considered in relation to the area of each land system. They show that away from the main roads centred on Bauchi the lack of communications is widespread. The situation is worst south of the Maijuju River and east of the Gongola. The few existing roads are oriented towards neighbouring states and not towards Bauchi. viii . The problem posed by labour shortage in the rural areas in consequence of rural urban migration Gosden (1978) has produced farming calendars for a number of localities in the Bauchi Plains that show that shortage of labour is a common restraint to production, particularly at weeding times. Lack of money at this time prevents additional labour being hired, though the labour is available from other areas. 104 Additional constraints There is a lack of effective farmers» organisations which would enable farmers to request and benefit from more effective extension advice, bulk purchase of inputs and handling of produce, credit facilities and tractor'hiring units. 105 RESEARCH NEEDS A long—term programme of research should be established to answer some of the problems to be encountered during development. Topics needing investigations are summarised below. 1. Trials to test varieties, fertiliser treatments and cultivation practices related to specific soils in the Bauchi Plains. For example, many of the soils have large amounts of coarse material and with present technology are considered to present limitations to the growth of crops. Research should be aimed at producing varieties or technologies that will overcome or at least reduce these limitations. 2. The long-term effects of intensive crop production on the often infertile and poorly structured soils of the area need study: in particular the long term effects of mechanised agriculture in relation to differing management practices and rotations. 3. Methods of adapting pasture improvement techniques to wide-scale implementation need investigation. 4. Practical methods of improving the nutrition and health of young stock in the ordinary nomadic herd need to be devised. 5. A socio-economic study of Fulani practices and attitudes is needed, particularly of those on the Bauchi to Abuja axis. 6. Trial plantings of a range of economic farm trees should be started. The most commonly occurring species at present are Parkia clappertonia and Acacia albida which are difficult to establish and grow slowly. Species that should be tried are: Butyrospermum paradoxum, Adansonia digitata, Sclerocarya birrea, Prosopis africana, Tamarindus indica, Diospyros mespiliformis and Cordyla pinnata. The most successful indigenous species in the Sudan zone is Acacia nilotica (bagaruwa). It is useful because it grows fast on a range of sites including poorly drained clay soils and because it provides several useful 106 products - firewood at the end of the rotation, tannin for goat leather and cattle fodder from the seeds. State or Federal Forestry Departments should have a trial planting programme as a suitable exotic species has not yet been found for the Sub-Sudan and Northern Guinea - Sudan zone boundary» The most promising species are Eucalyptus camaldulensis and Dalbergia sissoo, but the low rainfall and severe dry season cause deaths and slow growth in the eucalyptus. Dalbergia has a very light canopy which means that grass competition is a problem for many years. 107 Part 5 Part 5 References ADETUNJI (1974) Need for soil testing, fertiliser, yield correlation studies for sound recommendations for fertiliser use. Paper, National Seminar on Planning and Organisation of Fertilisers. ALFORD M & TULEY P (1974) Interim report on the landforms, soils and vegetation of the Bauchi Area. Volume 2. Miscellaneous Report. Land Resources Division, UK Ministry of Overseas Development no. 152. BENOIT T (1976) A study of variability of the growing season in northern Nigeria. Paper, Nigerian Geographical Association Conference no. 65. BLAIR RAINS A (1975) Livestock, production in the Central Nigeria Project area. Miscellaneous Report, Land Resources Division, UK Ministry of Overseas Development no. 198. BLAIR RAINS A (1978) Land resources of central Nigeria. Rangeland and livestock production. Land Resource Report, Land Resources Division, UK Ministry of Overseas Development no. 18. CENTRAL PLANNING OFFICE (undated) Third National Development Plan 1975-80. Lagos: Federal Ministry of Economic Development. FARGHER M N (undated) The Basement Complex geology of 1:100 000 Sheet Ï48, Toro, Bauchi Province. Report, Geological Survey of Nigeria>no. 1336. FOOD AND AGRICULTURE ORGANISATION (1974) Soil map of the World. Vol. 1. Legend. Paris: UNESCO. GOSDEN P N (1978) Land resources of central Nigeria. Farming systems. Land Resource Report, Land Resources Development Centre, UK Ministry of Overseas Development, no. 17. HILL I D, HUTCHEON A A, RACKHAM L J & WOOD A W (1974/5) Interim report on the landform, soils and vegetation of the Bauchi Area. Volumes 1 and 3. Miscellaneous Report. Land Resources Division, UK Ministry of Overseas Development no. 152. . r 109 HOWARD W J (1976) Land resources of central Nigeria: Forestry. Land Resource Report, Land Resources Division, UK Ministry of Overseas Development no. 9. JACOBSON R R E, MACLEOD W N & BLACK R (1958) Ring complexes in the Younger Granite provinces of northern Nigeria. Memoir, Geological Society of London no. 1. KOWAL J M & KNABE D T (1972) An agroclimatological atlas of the northern states of Nigeria. Samaru, Zaria', Nigeria.' Ahmadu Bello University. MACLEOD W N, TURNER D C & WRIGHT E P (1971) The geology of the Jos Plateau. Bulletin, Geological Survey of Nigeria no. 32. MANSFIELD J E (in preparation) Land resources of central Nigeria. The interpretation of environmental data in terms of limitations to crop growth. Land Resource Report, Land Resources Development Centre, UK Ministry of Overseas Development, no. 22. MANSFIELD J E (in press) The concept of,a minimum sized economic farm unit for northern Nigeria. Miscellaneous Report^Land Resources Development Centre, UK Ministry of Overseas Development. MILLER T B, BLAIR RAINS A & THORPE R J (1963) The nutritive value and agronomic aspects of some fodders in northern Nigeria. II Silages. Samaru Research Bulletin, Institute for Agricultural Research. Ahmadu Bello University, Nigeria,no. 31. NORMAN D W (1972) An economic study of three villages in Zaria Province. 2, Input-output study. Vol i, Text. Vol ii, Basic data on survey forms. Samaru Miscellaneous Paper. Institute for Agricultural Research, Ahmadu Bello University, Nigeria,no. 37/38. TAYLOR N H & POHLEN I J (1962) Soil survey method. Soil Bureau Bulletin, New Zealand Department of Scientific and Industrial Research^no. 25. US DEPARTMENT OF AGRICULTURE (1951) Soil Survey Manual. Agriculture Handbook, US Department of Agriculture no. 18. 11Ó WILLIAMS C N & JOSEPH K T (1970) Climate, soil and crop production in the humid tropics. London: Oxford University Press. Ill Appendixes APPENDIX 1 INTERPRETATION OF SOIL DATA Al INTERPRETATION OF SOIL DATA IN RELATION TO THE GROWTH OF MAIZE, MILLET, SORGHUM, GROUNDNUTS AND COTTON Al Depth Al Drainage A 2 Texture A4 Coarse material A5 Soil chemical properties A7 pH water A7 Phosphorus A8 Potassium A8 Cation exchange capacity (CEC) A8 Soil limitation categories (SLC) A9 Soil limitation categories in relation to crop yields A9 Soil limitation categories in relation to land systems All Ranking of land systems A12 INTERPRETATION OF SOIL DATA IN RELATION TO THE GROWTH OF YAMS A12 INTERPRETATION OF SOIL DATA IN RELATION TO THE GROWTH OF RAINFED RICE A13 APPENDIX 2 ASSESSMENT OF EROSION HAZARD A17 APPENDIX 3 MINIMUM SIZE OF ECONOMIC FARM UNIT A19 APPENDIX 4 EVALUATION OF THE GROWTH POTENTIAL OF FOREST RESERVES A21 Appendix 1 Interpretation of soil data INTERPRETATION OF SOIL DATA IN RELATION TO THE GROWTH OF MAIZE, MILLET, SORGHUM, GROUNDNUTS AND COTTON The soil physical properties of depth, drainage, texture of the surface 50 cm and the amount of coarse material are considered to have an important effect on crop production. They are all properties that cannot be modified without major soil improvement programmes. They have been divided into classes and given a coded annotation: each class has been assessed as a nil, minor, moderate or severe limitation to the growth of maize, millet, sorghum, groundnuts or cotton. •In addition to soil physical properties, certain chemical properties may be limiting to crop growth. Data are available for pH, CEC, levels of potassium and available phosphorus, and each of these has also been divided into classes and assessed as a limitation to the growth of the crops considered. Each of the soil properties is discussed below. The classes into which they have been divided, and their coded annotation, are given in the tables, together with the assessment of each class as a limitation to the growth of the crops considered. In the project area* yam, Irish potatoes and rainfed rice are grown under special conditions which"are discussed separately at the end of this Appendix. Depth The effective depth of the soil is considered to be that depth beyond which roots will not readily penetrate due to the presence of rock, ironpan or a permanent high water table. The depth classes and codes are given in Table 1 and assessed as limitations to the growth of crops. *Yam cannot be grown as a rainfed crop in the Bauchi Plains, Kano Plains and northern Kaduna Plains. Irish potatoes can only be grown on the Jos Plateau. Al TABLE 1 Depth classes and codes assessed as limitations to the growth of certain crops *Limitation to the growth of Depth Soil Groundnut Groundnut class code <. 140 day > 140 day cm Maize Millet Sorghum Cotton rainy rainy period period ? 150 DO Nil Nil Nil Nil Nil Nil 150-100 Dl Nil Nil Nil Nil Nil Nil 100-50 D2 Nil Nil Nil Nil Nil Mod. 50-25 D3 Mod. Mod. Mod. Mod. Nil Sev. < 25 D4 Sev. Sev. Sev. Sev. Sev. Sev. *Depth not limiting to yams on large ridges or mounds unless <25 cm, when severe limitation Shallow soils limit root development, thus inhibiting nutrient and moisture uptake which results in low yields. Shallowness is least limiting to shallow rooting crops such as groundnuts. Even soils of 50-25 cm depth impose no limitations to groundnuts if the rainy period is greater than 140 days, as significant periods of water stress are unlikely. Shallowness is most limiting for cotton which is a deep-rooting crop that also requires soil moisture after the end of the rainy season for optimum yields. Drainage Soil drainage has been assessed on the basis of soj.1 colour, with pale colours being correlated with poor drainage. The criteria used are similar to those given in the Legend to the Soil Map' of the World (FAO 1974). Imperfectly drained soils have been subdivided and the soil codes W2-W4 represent a seasonal water table increasingly closer to the surface. The only certain way of determining the drainage characteristics of a soil is to record seasonal watertable fluctuations, but this was not possible over such a large area: the drainage classes should therefore be considered as tentative. The drainage classes and codes are given in Table 2 and the assessment of these classes-as limitations of the growth of crops in Table 3. A2 TABLE 2 Drainage classes defined on the basis of colour -- Drainage class Colour criteria and depth Soil code Well drained 1. Soils lacking properties óf WO codes W1-W5 ii ii 2. Gleyic horizon colour or >20% gley spot mottle at Wl 100-150 cm Imperfectly drained 1. >20% gley spot mottles W2 at 50-100 cm II H 2. Gley horizon jnatrix W3 colours at 50-100 cm II II .3. >10% gley spot mottles or W4 imperfect matrix colours at < 50 cm Poorly drained 1. Gleyic horizon matrix W5 colours, at «.50 cm TABLE 3 Soil drainage assessed as limitations to the growth of certain crops Limitation to the growth of// Groundnut Groundnut ^140 day >140 day Soil Code Sorghum Cotton Maize Millet rainy rainy period period WO Nil Nil Nil Nil Nil Nil Wl Nil Nil Nil - Nil Nil Min. W2 Min. Nil Nil Nil Nil Mod. W3 Min.* Miri. Min./ Min Nil Mod.** W4 Mod. Mod. Min. Mod. Min. Sev. Sev. W5 Sev. Sev. Sev. Sev. Sev. * For maize if this degree of limitation is found in combination with two others.one of which is texture.it is treated as a moderate limitation / For sorghum as for * ** For cotton as for * & / but treated as a severe limitation under these conditions // Drainage not limiting for yams grown on large ridges or mounds | Impeded drainage is a limitation to the growth of all the crops considered because they will not tolerate the anaerobic conditions of water-saturated soils: groundnuts, cowpeas and other legume crops are particularly adversely affected by waterlogging. Shallow-rooting crops such as groundnuts are less affected by waterlogging in the lower part of the soil profile, whilst deep- rooting crops' such as cotton are most affected. Although sorghum and maize have similar rooting habits, the former is more tolerant of wet conditions in the later stages of growth. The limitations imposed by drainage shown in Table 3 reflect the fact that the soil codes WO-W5 are thought to represent seasonal water saturation increasingly near the surface. A3 A complicating factor in assessing the limitation imposed by imperfectly drained soils is that in a dry year, such soils support better crop growth. This is offset by the fact that in a year of above average rainfall soils may be even more limiting than is shown in Table 3. Texture Texture of the surface 50 cm only is considered because most of the feeding roots of annual crops are concentrated there. Four broad textural groups have been defined corresponding in general to clayey, loamy, sandy and coarse sandy soils. The textural classes in each group are shown in Table 4, together with the assessment of these groups as limitation»to the growth of certain crops. TABLE 4 Groups of textural classes and soil codes assessed as limitations to the growth of certain crops Limitation to the growth of Soil Yam (on large Texture class code ridges or mounds) * Maize Millet Sorghum Groundnut Cotton //180-199 >200 CL,C,SC,SiCl,SiC Tl Nil Min. Nil Min. Nil Nil Nil L,SCl,SiL,Si T2 Nil Min. Nil Min. Nil Nil Nil S,fS,L5,LfS,SL,fSL T3 Min. Nil. Min. Nil Min./ Mod. Min. cS,Lc~S,cSL T3c Min. Nil Min. Nil Mod. Mod. Mod. * Where appropriate a subscript + is given to those profiles where 10-20 cm has a finer texture. Where appropriate a subscript - is given to those profiles where 10-20 cm has,a coarse texture / For cotton T3 + is a minor limitation (t), T3 is treated as a moderate limitation (Ta) with regard to Soil Category 2 but as a minor limitation when considering effect of texture in Categories 3, 4 or 5. //Rainy period in days C = clay, L = loam, S = sand, Si = silt, f = fine, c = coarse. The four textural groups reflect differences in available waterholding capacity (Williams and Joseph 1970). This is of particular significance in assessing the limitations presented by any soil to the growth of cotton A4 and late planted millet, which require a minimum of 11„8 cm (4.6 in) and 7.2 cm (2.8 in) of available soil water after the end of the rainy period respectively. , Calculation of the mean depths of soil required for various textural groups to hold the above amount of water indicates that,apart from CS, C'XS, CSL' (T3C group), the differences are less than 20 cm and the variation in AWC (available Vater Capacity) due to texture has little practical significance for most rainfed crops. Nutrient availability and aeration are also related to texture so maize, sorghum and cotton require medium and fine textured soils for optimum yields but millet and groundnuts will yield adequately on coarser textured soils. In the case of groundnuts this is an indirect effect as they will grow well on heavier soils, but are difficult to harvest. Management of heavy clay soils, particularly of montmorillonitic clays, may also be a limitation because of their physical characteristics: (a) they become sticky and puddle when wet, (b) they crack on drying out which may cause rupture of roots, (c) rain water flows rapidly down the cracks with little moisture retained near the surface: when the cracks close water tends to stand on the surface. Coarse material This includes all the hard soil particles greater than 2 mm in diameter; they may be rock fragments, mineral grains or concretions. Both the amount of coarse material and the depth over which it occurs are significant to crop growth and in Table 5 various combinations of percentages of coarse material and the depths at which they occur are used to define seven classes shown as CO to C6. The percentage of coarse material is assessed in the field as a volume percentage. A5 TABLE 5 Percentages of coarse material in various depth ranges in seven classes represented by codes CO to C6 Mean coarse material Depth ranges over which Soil code percentages coarse material occurs '<20 0-100 cm CO '<20 0-50 cm CI 20-40 50-100 cm 20-40 O-lOO cm C2 20-40 0-50 cm C3 40-60 50-100 cm «40 0-50 cm C3(s) > 60/Rock/Hardpan from 50 cm 40-60 O-lOO cm . C4 40-60 0-50 cm C5 >60 50-100 cm 40-60 0-50 cm C5(s) Rock/Harpan O-lOO cm >60 O-lOO cm C6 > 60 0-50 cm C6 >60 50-100 cm (s) shallow The assessment of these classes as limitations of certain crops is given in Table 6. TABLE 6 Coarse material soil codes assessed as limitations to the growth of certain crops Limitation to the growth of Soil code Maize Millet Sorghum Groundnut Cotton Yam* CO Nil Nil Nil Nil Nil Nil CI Nil Nil Nil Nil Min. Nil C2 Min. Min. Min. Min. Min. Nil C3 Min. Min. Min. Min. Mod. Nil C3s Min. Min. Min. Min. Sev. Nil C4 Mod.. Mod. Mod. Mod. Mod. Mod. C5 Mod. Mod. Mod. Mod. Sev. Mod. C5s Mod. Mod. Mod. Mod. Sev. Mod. C6 Sev. Sev. Sev. Sev. Sev. Sev. *On largeÏ ridges o:c mounds A6 Coarse material reduces available waterholding capacity by reducing the volume of soil so its effect is most pronounced on cotton which requires moisture after the end of the rains to give maximum yields. This also adversely affects the yields of maize, millet and sorghum but to a lesser extent. Coarse material also affects the root penentration and reduces overall nutrient status. Large amounts of coarse material in the surface horizons of soils may make cultivation more difficult and thus has an indirect effect on crop production. Soil chemical properties Low levels of certain soil chemical properties can limit crop yields. The most important for which data from routine soil analyses is available are con sidered to be 1. Soil pH (water), 2. Phosphorus, 3. Potassium, and 4. Cation exchange capacity (CEC). 1. pH (water) The limitations due to pH are shown in.Table 7. TABLE 7 Limitations imposed by pH to the growth of certain crops Crop pH range (water) Limitation Maize 5.5-7.5 Nil 5.2-5.4 Minor 4,5-5.1 or 7.6-8.0 Moderate <4.5 or >8.0 Severe Sorghum 5.5-7.5 Nil 5.0-5.4 Minor 4.5-4,9 or 7.6-8.O Moderate <4.5 or >8.0 Severe Millet 5,0-6.5 Nil 4.5-4.9 or 6.6-7.0 Minor 4.0-4.4 or 7.1-8.0 Moderate <4.0 or >8.0 Severe Rice (Swamp) 4.5-7.O Nil 3.0-4.4 or 7.1-7.5 Minor 7.6-8.0 Moderate <3.0 or ?-8.0 Severe Cotton 5.0-6.O Nil 4.5-4.9 or 6.1-6.5 Minor 4.0-4.4 or 6.6-7.5 Moderate <4.0 or >7.5 Severe Groundnuts 5.5-6.5 Nil 5.0-5.4 or 6.6-7.o Minor 4.5-4.9 or 7.1-7.5 Moderate <4.5 or ?7.5 Severe Yam (on large 5.0-7.0 Nil ridges or 4.5-4.9 or 7.1-7.5 Minor mounds) 4.0-4.4 or 7.6-7.8 Mode rate 4.0 or >8.0 Severe aiaai •= —= • - i A7 2. Phosphorus There are not sufficient data on phosphorus availability as determined by the Truog method to make generalisations related to land systems. Phosphorus availability is related to pH and the limitations due to phosphorus availability were assessed as in Table 9. TABLE 8 Limitations due to phosphorus availability related to pH pH Limitation 6.5-7.5 Nil 6.0-6.49 7.51-8.O Minor 5.0-5.9 8.1-8.5 Moderate <5.0 Severe 3. Potassium The assessment of different levels of potassium in terms of plant needs is given below. 0 At pK >4.5 0.15 meq/lOO gin soil Luxury 0.1-0.15 Adequate < O.l " " " Deficient b) At pH<4.5 the assessment is based on the potassium saturation percentage: where this is > 2, levels are thought to be adequate, where it is '< 2 levels are thought to be deficient. 4. Cation exchange capacity (CEC) Little is known about critical levels of CEC with respect to retention of potassium, calcium and magnesium cations under leaching conditions of intensive rainfall. Adetunji (1974) related CEC levels to the ability of a soil to withstand intensive cultivation. These level are given below, based on his classification. CEC y8 meq/lOO gm soil Suitable for intensive agriculture 2-7.9 " " " Requires a high ratio of fallow or grass legume pasture to crops < 2 " " " Unsuitable for production of annual, arable, rainfed crops A8 Soil limitation categories (SLC) Limitations due to any of the factors discussed above may occur in soils in a variety of combinations. For example, reference to Tables 1, 5 and 6 shows that a soil of 25-50 cm depth with a high percentage of coarse material would have two severe limitations to the growth of any of the crops considered,whilst a soil of similar depth and no coarse material is considered to have only one severe limitation Üue to depth) for cotton and only a moderate limitation for maize or millet or sorghum. Various combinations of nil, minor, moderate and severe limitations have been used to define five soil limitation categories(Table 9) based only on the limitations due to the physical characteristics. No attempt has been made to consider the interrelationships of the physical and chemical soil characteristics. A soil is placed in a soil limitation category on the basis of its physical characteristics; any limitation due to chemical characteristics is noted separately. As the soil characteristics are interpreted differently for different crops it follows that the limitation category is specific to a given crop. Soil limitation categories in relation to crop yields An attempt was made to check whether the soil limitation categories are related to actual crop production. The yields of a variety of crops grown on State demonstration plots were collected. However, differences in yield due to climatic or management factors were so great that it was not possible to correlate differences in yields with soil differences. In other experiments done in the project area information about the soils is generally inadequate. The soil limitation categories must therefore be considered tentative. However they have been defined after discussion with a wide range of research workers and practising agriculturalists in Nigeria. They can therefore be considered as a consensus opinion of the limitations imposed by soil characteristics to the growth of crops. A9 TABLE 9a Nature and degree of limitations shown in Table 9b Letters used to denote the Nature of limitation deqree of limitation Nil Minor Moderate Severe Depth (D) 0 N/A D D Drainage (W) 0 w W W Texture (T) 0 t Ta, tb* N/A Coarse material (C) 0 c C C *Ta or Tb are treated as a moderate limitation for Categories 1 and 2 only. For Categories 3, 4 and 5 they are treated as a minor limitation TABLE 9b Combinations of the degrees of limitation acceptable in each soil limitation category for rainfed maize, millet, sorghum, groundnut, cotton and yam (grown on mounds or large ridges) 1 2 3 4 5 0 w D Dw DW + or - c, t, or Ta t wt Dt DWC + cr - t, or Ta c v/Ta DTa DWC + or — t or Ta wt * wtc/ Dwt/ DWC tc * wTac DwTa DC + or - t, Ta or Tb wc Dtc DC + or - t, Ta, or Tb W DTac D + or - any combination Wt Dc WC + or - t, or Ta WTa wC WC + or - t, or Ta tc wtC/ WC + or - t, or Ta tc wTaC Tt>C TaC wtC** TbC Ta WTac * * Tb Wc C WC W WTa Wtc Wc tc ' TaC C * These combinations only permitted fo:c sorghum and millet / for Maize if drainage code is W3(w) jEo r this combination the drainage becomes a moderate limitation W for Sorghum if drainage code is W3(w) for this combination the drainage becomes a moderate limitation W ** for Cotton if drainage code is W3(W) for this combination the drainage becomes a severe limitation W Therefore in both cases / and . ** t:h e limitation category for that soil would go down one Ta Texture limitation applicable tc> cotton only. Tb Texture limitation applicable tc3 Yam only when grown in areas with 180-199 day rainy period A10 Soil limitation categories in relation to land systems The land systems shown on Separate Map 1 are defined in terms of their landform, soils and vegetation. The soils are grouped according to depth, drainage, texture of the surface 50 cm and amount of coarse material; the groups are represented by codes as discussed in previous sections of this appendix. An estimate is made of the percentage of each land system occupied by soils of a given code. The area <>f each facet in each land system is first measured on representative aerial photographs. Many land systems have a number of small facets, so, to simplify the estimate, only facets occupying a mean- 18% (11-25/C range) or more of a land system are considered further: These facets usually make up more than 70% of the unit. The soils on any facet have been described by a number of soil pits and each soil is given a code. The number of pits of a given code, as a percentage of the total number of pits on the facet, is taken as the percentage of the facet occupied by soils of that code. As these percentages are only indicative they are given in percentage classes of <10, 10-29, 30-50 and/or 30-59 and>60. Soils of a given code can be assigned to one of the five limitation categories defined in the previous section. A land system can therefore be defined in terms of percentages of various limitation categories by summing the relative proportions of facets. For example, in Land System X (Table 10) the soils are in three groups. 30-59% of the land system has soils coded as D2W0 T3 + C2 i.e. soils of 50-100 cm depth, well drained, coarse textured surface horizons and 20-40% coarse material scattered throughout the soil profile. Shallow depth, free drainage and coarse texture are not limiting to the growth of millet, but the coarse material is considered as a minor limitation. (See Tables 1, 3, 4 and 6.) As the soil has only one minor physical limitation for millet, it is classed as limitation category 2. (See Table 9.) In the case of maize, the texture and the coarse material1 are both considered as minor limitations and by reference to Table 9 the soil is placed in soil limitation category 3. TABLE 10 Percentage of soils of various codes in Land System x an(^ their relationship to soil limitation categories for certain crops 1 1 % of land Soil limitation Land Soil code category by crop system in system D W T C each code Maize Millet Sorghum G'nut Cotton Yams* Rice X 2 O 3 + 2 30-59 3 2 2 2 4 1 S 2 O 3+ 5 10-29 3 3 3 3 5 3 S 0 3+ 0 10-29 2 2 1 1 1 1 3 s *0n large ridges or mounds A11 Ranking of land systems Land systems with the highest proportion of SLC 1 land have least limitations ' to the growth of a given crop» If two land systems have a high proportion of SLC 1 land, the one in which the remaining land is SLC 2 or 3 can be considered to be better than the one in which the remaining land is SLC 4 or 5. A land system is considered especially favourable for the production of a crop if it has one of the following combinations of SLCs: - at least 30-50% SLC 1 + any other SLC - Ji> 60% SLC 2 - at least 30-50% SLC 2 + 10-29% SLC 1 - 30-59% SLC 2 + 10-29% SLC 3 - 10-29% SLC 1 + 10-29% SLC 2 + 10-29% SLC 3„ Land systems with these combinations of Soil Limitation Categories are shown on the legend of Separate Map 3. The legend of Separate Map 1 shows the percentages of the Soil Limitation Categories in all the land systems in the area. INTERPRETATION OF SOIL DATA IN RELATION TO THE GROWTH OF YAMS This crop is grown either on mounds or large ridges within the project area« This method has a number of advantages over 'on-the-flat' cultivation practiced in other parts of Nigeria - mainly on free draining, deep, alluvial sandy loams with little, if any, coarse material and a relatively high fertility. Observational trials carried out on the Jos Plateau (Pankshin area) have shown that higher yields are obtained from mound cultivation as opposed to ridge cultivation. The following soil conditions achieved by mound/ridge cultivation are considered to be advantageous to the development of yam tubers: 1. The soil is broken up into a relatively friable medium and finer textured soils do not present the same 'resistance' to tuber expansion as would be the case with 'on-the-flat' cultivation A12 2. In areas suffering from seasonal waterlogging, mounds raise the tubers above the level where anaerobic conditions occur and in fact produce the free draining.conditions required for optimum tuber .development 3. The depth of the soil is artificially increased enabling yams to be grown on soils which would be too shallow to 'on-the-flat' cultivation 4. The presence of a layer of coarse material within the growing depth for the tuber has been shown at UTA, Ibadan, to distort tuber development, preventing further downward growth» When mounds or ridges are used, the coarse material is evenly distributed throughout the heap or mound and is likely to have much less impedance on tuber development» It is considered that a mean of up to 20% coarse material by volume is not limiting when the crop is grown on mounds or ridges. 5„ The crop is relatively easy to harvest The only possible disadvantage of mounds or ridges could be the increased rate of drying out of the soil due to the larger surface .area exposed to the sun, ridges being worse in this respect than mounds. In the project area and particularly in the Benue Valley with its longer rainy season and reliable rainfall this effect is considered to be of little importance, even when coarse-textured soils (which can dry out more rapidly) are. considered To summarise the above, provided 25 cm depth of soil is available, soil depth is not a limitation for yams grown on ridges. There is no limitation imposed by poorly drained soils. Variations in soil texture are of only minor importance and the adverse effect of coarse material is lessened. INTERPRETATION OF SOIL DATA IN RELATION TO THE GROWTH OF RAINFED RICE In the project area the crop can be grown on three main drainage positions:- 1. Shedding sites, such as crest, upper, middle and planar or convex slope which are dependant entirely on the direct rainfall which enters the'soil. They may either have (a) free draining soils, or (b) soils with imperfect drainage usually associated with shales or hardpan near the surface giving rise to a perched watertable. A13 Free draining soils require reliable rainfajl distributed evenly over the growing season (ideally at least 5 mm/day). A drought of 10 days duration on soils with a low water-holding capacity, either at the early stages of growth, or between the beginning of flowering and the. milky (soft) grain stage can reduce yield by up to 80%. Upland rice on free-draining soils is becoming an increasingly important cash crop in the Benue Valley south of the Benue River» The area appears to have a northern limit which coincides with the mean 1 300 mm (50 in) rainfall isohet as drawn by Kowal and Knabe (1972). It is assumed that areas south of this line are unlikely to suffer from significant drought periods during the growing season. Rice can, therefore, be grown on free-drainage soils in these areas, providing the same site is only used once in 5 years with an intervening fallow to enable the build up of organic matter and hence soil waterholding capacity. Elsewhere in> the project area such sites are considered unsuitable for rainfed rice production unless perched watertable conditions prevail which would probably enable the crop to be unaffected by drought periods of up to 15 days without n — jr • _ -i -a 1U3S ui yj-CLU. 2. Receiving sites, such as concave lower slopes and valley heads. These sites not only receive water from direct rainfall but also water passing through soils from areas further up the slope. Such sites also receive run-off water which is usually transient. 3. Flooding sites, such as valley bottoms, floodplains and lower river terraces The sites receive direct rainfall water passing through the soil from higher up the interfluve, run-off water and possibly flood water. Sites 2 and 3 are considered the most suitable areas on which to grow rainfed rice over most of the project area. Such areas are usually minor facets of the land system (less than 10%) of the total area and are, therefore, not usually considered in our overall assessment of land systems which excludes soils data relating to minor facets. The specific soil limitations for the crop are coded in Table 11. A1*f TABLE 11 The range of code numbers permitted for key soil characteristics in each soil limitation category for rainfed rice a. In areas <1 300 mm rainfall and < 200 day rainy period These areas have a risk of water stress when soil has no limitations. b. Varieties with 100-200 day growing period Category D W T C 1 0/1/2/3 5 1/2 0/1/2/3 0/1/2 4 1/2 0/1/2 2 0/1/2/3 5 3/3+ 0/1/2/3 3 5 1/2 3s 0/1/2 4 3/3+ 0/1/2 3 3 5 3/3+ 3s 0/1/2 4 1/2/3/3+ J 4 0/1/2/3 5 Any 4 0/1/2 4 Any 4 0/1/2 3 1/2 0/1/2/3 5 3 4 Any 3s 0/1/2 Any Any 5/6 0/1/2/3 0/1/2 Any Any 0/1/2 3 3/3+ Any 0/1/2/3 3 1/2 4 3 3 1/2 3s 4 Any Any Any Categories 1, 2 and 3 are only likely to occur in lower slope or valley bottom situations or when conditions give rise to a perched watertable. Categories 1 and 2 includes 1-, 2+ or 2-. A15 Appendix 2 Assessment of erosion hazard Erosion hazard has been assessed on the assumption that open field clean cultivation techniques are to be used. Three main factors are then considered to affect the degree of erosion to which an area is subjected, the length and steepness of slope, the duration and intensity of rainfall and the infiltration characteristics of the soil. Slope is taken as the most important variable in the assessment of erosion hazard. Four slope categories have been defined. a) <1% (0„5°) These areas should not require mechanical protection works. The use of grass strips and contour ploughing should give adequate erosion control. b) 1-3% (0.6-1.75°) These areas require normal mechanical protection works which include graded terraces and grassed protected waterways. Contour ploughing and strip cropping should be practised. Mean contour intervals should range between 240-127 ft. c) 3.1-10% (1.76-6°) These areas require normal mechanical protection works organised on a catchment rather than an individual farm basis. They should not be used for large scale mechanical farming schemes based on the rainfed crops considered in this report: the short inter-terrace intervals and complexity of the layout mean that economic running of machinery is extremely difficult and is only worthwhile for high value crops such as tobacco. d) >10% (6°) These areas have a high erosion hazard and intensive conservation measures such as bench terracing are required. They are more suited to tree crops than arable crops. Total protection is recommended. Data are not available for the project area on the duration and intensity of rainfall, but the start of the rainy season is characterised by short, heavy, violent rainstorms, having a high erosive power. It was not possible to subdivide the area according to the rainfall pattern, A17 Most of the soils in thé project area rapidly form a capping which reduces infiltration: trampling by cattle may add to the problem. No quantitative measurements have been made so there has been no attempt to rank the soils according to their infiltration characteristics. A18 Appendix 3 Minimum size of economic farm units (provisional) It has been suggested by Mansfield (in press) that a farm should produce a minimum net income of N 900 per annum, corresponding- to that of many daily paid government employees. Norman (1972) has shown that most farmers derive about 22% of their income from off-farm activities so farmers would have to derive » 740 from the farm. It has been assumed that 1. The farming system is based on annual rainfed crops 2. The farmer grows only one cash crop which is the one that brings him the highest net return per unit area and has the least environmental limitations to growth 3. All farmers used improved practices such as early planting, improved seed, fertiliser and insecticidal sprays. The minimum size of farm unit has been calculated for farms on which the main cash crop is one of the following: maize, sorghum, groundnuts, cowpeas and cotton. It has been calculated for three types of farm: Type 1 Hand labour only Type 2 Family labour and draught oxen Type 3 Family labour + draught oxen and herbicides to control iaiter-plant weed growth For Type 1, labour must be hired in order to cultivate the amount of land required to produce the minimum income. The theoretically calculated farm sizes are given in Table 1 for farms with no fallow and farms where one third of the farmed area is under fallow. A19 TABLE 1 The minimum size of farm unit required to produce an annual income of W 740 of various types of farm and with various cash crops Minimum farm size Farm type Cash crop No fallow 1/3 fallow ac ha ac ha I» Hand labour only Maize 12.35 5.00 18.53 7„50 Groundnuts 9.18 3.22 13.77 5.57 Cowpeas 9.59 3.88 14.93 6.04 Cotton 10.21 4.13 15.23 6.16 2. Family labour + Maize 38.05 15.40 46.73 18.91 draught oxen Sorghum 31.41 12.71 36.76 14.88 Groundnuts 26.13 10.57 28.84 11.67 Cowpeas 28.77 11.64 32.81 13.28 Cotton 23.35 9.45 24.67 9.98 3. Family labour + Maize 44.51 18.01 56.41 22.83 draught oxen -t Sorghum 35.05 14.18 51.72 20.93 herbicides Groundnuts 26.78 10.84 29.83 12.07 Cowpeas 28.39 11.49 32.24 13.05 Cotton 31.57 12.78 37.00 14.97 In practice,actual farm sizes will need to be larger because the farmer does not grow a single cash crop. A20 Appendix 4 Evaluation of the growth potential of forest reserves The extent to which a particular soil property is limiting to a plantation species is estimated by relating measured sample plots to the characteristics of the underlying soil and from a knowledge of the species' site requirements. Many soil limitations such as depth and coarse material inhibit the growth of practically all species, but some species flourish in conditions that might inhibit the growth of others; for example Eucalyptus spp. tolerate poorly drained soils whereas teak, Gmelina and neem do not. The Icasses and codes for depth, drainage, texture and coarse material content of a soil, used to assess limitations to the growth of various crops, are also used for tree species. In Table 1 these classes are ranked and given a score for teak, Gmelina, Eucalyptus, neem and Dalbergia. For any given soil the total limitation score for a species is obtained by adding the code values that affect that species. Facets of the land systems are allocated limitation scores according to the predominant soil series. This information is obtained from the description of the soil series given in Hill and Rackham (1974). If a facet has dominant soil series with different limitation scores the percentage that the facet occupies in the land system is divided between the scores. For example: 1. In Maigama Reserve on the Bauchi Plains, Facet i occupies 21% of Land System 36 (Table 2a).*, There are three dominant soil series, Gyangyan, Kurba and Zaranda. The first two have soil limitation scores for Eucalyptus of 1 and Zaranda has a score of 3. The 21% is therefore divided between the 0-2 and 3-4 limitation score classes. 2. In Naraguta Reserve, on the Jos Plateau, Facet iv occupies 7% of Land System 113 (Table 2b) *.There are two dominant soil series, Mushere and Vwang» Mushere has a soil limitation score for Eucalyptus of 4 and Vwang has a score of 1. The 7% is therefore divided equally between the 0-2 and 3-4 limitation score classes. *The forest reserve relevant to this volume only is shown as Table 2. A21 3. In Nimbia Reserve on che Jema'a Platform, Facet iii occupies 35% of Land System 218 (Table 2c). There are two dominant soil series, Muilafia and Jenta. Mailafia has a soi_. limitation score for teak o.r 1 and Jenta has a score of 3. The 35% is therefore divided equally between the 0-2 and 3-4 limitation score classes. 4. In Shangev Tiev in the Benue Valley(Facet ii occupies 34% of Land System 501 (Table 2d), of the two dominant soil series, one has a limitation score for teak and Gmelina of 1 and the other of 2. The 34% is therefore allocated to the 0-2 limitation score class. The limitation score for any land system is obtained by adding the percentages in the three classes 0-2, 0-3 and 5-6. This is intended as a very general guide to the growth potential of a land system for plantation forestry. In Table 2 the limitation scores for the land systems in the above forest reserve relevant to this volume are given. In the forestry report, Howard (1976) has related the increment of the major plantation species (teak, Gmelina, Eucalyptus and neem)to the soil limitation score. This information is used to provide the growth potential for the forest reserves. If the land system has more than 50% land with a score of 0-2, the overall score is taken as 0-2. If the score is 5-6 over more than 60%, the score is taken as 5-6 and the land considered unsuitable for plantation forestry. Land systems with intermediate scores are treated as having a score of 3. *The forest reserve relevant to this volume only is shown as Table 2, A22 TABLE 1 Soil Limitation Scores for teak, Gmelina, Eucalyptus, neem and Dalbergia Soil property Soil limitation score (SLC) Heading Description Code Teak Gmelina Eucalyptus Neem Dalbergia Depth (D) 150 cm 0 150-lOO cm 1 1 1 1 1 1 50-100 cm 2 2 2 2 2 2 25- 50 cm 3 3 3 3 3 3 25 cm 4 4 4 4 4 4 Drainage Free draining (W) to 150 cm 0 Imperfect at lOO cm 1 1 Imperfect at 100-50 cm 2 1 Poor at lOO- 50 cm 3 1 1 1 Imperfect at 50 cm 4 1 1 1 •Poo r at 50 cm 5 1 1 1 Texture (T) Fine 1 1 Top 50 cm Medium 2 Coarse 3 Texture (T) Fine 1 1 50-150 cm Medium 2 .Coarse 3 1 1 Coarse C None 0 material low 1 1 1 1 1 1 high 2 2 1 2 2 2 2 Example: A coded soil description might be D2W3T2^^c2 This soil would have a limitation score of 2(D) + 1(W) + 2(C) = 5 for teak, Gmelina or neem and a score of:- 2(D) +2(C) = 4 for Eucalyptus or Dalbergia A2 3 TABLE 2 How the soil limitation scores for the land systems in a forest reserve are worked out (Maigama Reserve on the Bauchi Plains) Major Soil Summary % of L.S. Land % of Series as Facet soil limitation occupied by each system system % of L.S. series score limitation group L 1 Mostly bare risk 100% unsuitable for planting 2 No facet Dutsin 6 17 analysis Zaranda 3 17 17% 0-2 Gubi 3 17 Gora 4 17 68% 3-4 . Jimin 1 . 17 17% 5-6 Boi 3 17 3 i 38 Zaranda 3 38 Gubi 3 Gora 4 24% 0-2 ii 7 Bar am 0 7 iii 38 Gubi 3 30 68% 3-4 Gora 4 Bar am O 10 7% 5-6 JZavai-u^ =» iv 7 Durum O 7 Wushi 1 Sanga 0 Mada 2 V 7 Dutsin 6 7 36 i 21 Gyangyan 1 14 Kurba 1 30% 0-2 Zaranda 3 7 51% 3-4 ii 44 Gubi 3 44 21% 5-6 iii 8 Gyangyan 1 8 Jimin 1 iv 8 Durum 0 8 Sanga 0 Wushi 1 Mada 2 V 21 Dutsin 6 21 Bas 51170/11567/12 700 11/78 PQ3 A24 Publications of the land resources development centre These publications have a restricted distribution and are not available to booksellers. The'Centre makes a report on each completed project. The report is published as a Land Resource Study or Technical Bulletin only with the consent of ..the government concerned. LAND RESOURCE STUDY (ISSN 0305-6554) *1 SPOONER R J & JENKIN R N (1966) The development of the Lower Mgeta River area of the United Republic of Tanzania (0 902409 75 l). *2 BAWDEN M G & TULEY P (1966) The land resources of Southern Sardauna and Southern Adamawa Provinces, Northern Nigeria (O 902409 74 3) • *3 BAWDEN M G & CARROLL D M (1968) The land resources of Lesotho (0 902409 73 5) • ' 4 JENKIN R N & POALE M A (1968) An investigation of the. coconut growing potential of Christmas Island (O 902409 71 9). 5 BLAIR RAINS A & McKAY A D (1968) The Northern Statelands, Botswana (0 902409 70 0). 6 HILL I D (1969) An assessment of the possibilities of oil palm cultivation in Western Division, The Gambia (O 902409 01 8). 7 MITCHELL A J B (1976) The irrigation potential of soils along the main rivers of eastern Botswana: a reconnaissance assessment (O 902409 52 2). 8 VERBOOM Vi C & BRUNT M A (l970) An ecological survey of Western Province, Zambia, with special reference to fodder resources. Volume 1, The environmen t (0 902409 68 9). Volume 2, The grasslands and their development (0 902409 69 7). *9 AITCHISON P J, BAWDEN M G, CARROLL D M, GLOVER P E, KLINKENBERG K, LEEUW P N de & TULEY P (1972) The land resources of North East Nigeria. Volume 1, The environment (O 903359 06 5). * Out of print *9 AITCHISON P J & GLOVER P E (l970) The land resources of North East Nigeria. Volume 2, Tsetse and trypanosomiasis (O 902409 02 6). *9 BAWDEN M G, CARROLL D M & TULEY P (1972) The land resources of North East Nigeria. Volume 3, The land systems (O 902409 08 5). *9 LEEUW P N de, LESSLIE A & TULEY P (1972) The land resources of North East Nigeria. Volume 4, Present and potential land use (O 903359 H l)• *9 TULEY P ed. (1972) The land resources.of North East Nigeria. Volume 5, Appendixes and tables (O 902409 09 3). 10 JOHNSON M S (l97l) New Hebrides Condominium. Erroman^o forest inventory (0 903359 01 4). *11 BLAIR RAINS A & YALALA M (1972) The Central and Southern State Lands, Botswana (0 903359 04 9). 12 BERRY M J & HOWARD W J (1973) Fiji forest inventory. Volume 1, The environment and forestiypes (0 902409 13 l)• Volume 2, Catchment groups of Viti Levu an'dTKandavu (0 902409 14 X) . Volume 3, Catchment groups of Vanua Levu (O 902409 15 8). 13 JOHNSON M S & CHAFFEY D R (1973) A forest inventory of part of the Mountain Pine Ridge, Belize (0 902409 67 0). 14 JOHNSON M S & CHAFFEY D R (1973) An inventory of the Chiquibul Forest Reserve, Belize (O 902409 17 4)• 15 JOHNSON M S & CHAFFEY D R (1974) An inventory of the southern coastal plain pine forests, Belize (O 902409 22 O). 16 HENRY P W T (1974) Pine forests of the Bahamas (O 902409 18 2). 17 BERRY M J, LAURENCE J F, MAKIN M J & WADDAMS A E (l9Y4) Development potential of the Nawalparasi area of Nepal (0 902409 16 6). Out of print 18 HANSELL J R P & WALL J R D (1974-7) Land resources of the British Solomon Islands Protectorate. Volume 1, Introduction and recommendations (0 902409 59 X). Volume 2, Guadalcanal and the Florida Islands (O 902409 20 4). Volume 3, Malaita and Ulawa (O 902409 21 2). Volume 4, New Georgia Group and the Russell Islands (O 902409 37 9). Volume 5, Santa Isabel (O 902409 60 3). Volume 6, Choiseul and the Shortland Islands (O 902409 61 l). Volume 7, San Cristobal and adjacent islands (O 902409 62 X). Volume 8, Outer Islands (O 902409 63 8). 19 MANSFIELD J E, BENNETT J G, KING R B, LANG D M & LAWTON R M (1975/6) Land resources of the Northern and Luapula Provinces, Zambia - a reconnaissance assessment. Volume 1, Introduction, conclusions and recommendations (0 902409 33 6). Volume 2, Current land use (O 902409 34 4). Volume 3, Land capability and development potential (O 902409 35 2). Volume 4» The biophysical environment (O 902409 41 7)- Volume 5? Social and economic factors (O 902409 42 5). Volume 6, The land systems (O 902409 51 4). 20 THOMAS P, ACRES B D, BOWER R P, BURROUGH P A, POLLAND C J, KALSI M S & WRIGHT P S (19?5) The soils of Sabah. Volume 1, Classification and description (O 902409 26 3). Volume 2, Sandakan and Kinabatangan Districts (0 902409 27 l). Volume 3, Western parts of Tawau and Lahad Datu Districts (O 902409 28 6). Volume 4, South-western Districts (O 902409 29 8). Volume 5f References and appendixes (O 902409 30 l). 21 MAKIN M J, KINGHAM T J, WADDAMS A E, BIRCHALL C J & TAMENE TEFERRA (1975) Development prospects in the southern Rift Valley, Ethiopia (O 902409 32 8). 22 DUNSMORE J R, BLAIR RAINS A, LOWE G N, MOFFAT D J, ANDERSON I P & WILLIAMS J B (1976) The agricultural development of The Gambia; an agricultural, environmental and uocioeconomic analysis (O 902409 64 6). 23 MURDOCH G, OJO-ATERE J, COLBORNE G, OLOMU E I & ODUGBESAN E M (1976) Soils of the Western State Savanna in Nigeria.. Volume 1, The environment (O 902409 49 2). Volume 2, Descriptions of Basement complex soil series (O 902409 50 6). Volume 3, Atlas of sample blocks mapped during the survey (O 902409 47 6). 24 " 'JENKIN-R N, ROSE INNES R, DUNSMDRE J R, WALKER S H, BIRCHALL C J & BRIGGS JS (1976) The- agricultural development potential of the Belize Valley, Belize (O 902409 39 5). 25 '- THOMAS P, LO F'K C & HEPBURN A-J (1976) Land capability classification of Sabah. • Volume 1, The Tawau Residency. Volume 2, The Sandakan Residency. Volume 3» The West Coast • ancL, Kudat Residencies. Volume 4, The Interior Residency and Labuan. 26' - MAKIN M'J, KINGHAM T J, WADDAMS A E, BIRCHALL C J & EAVIS B W (1976) Prospects'-for irrigation development around Lake Zwai, Ethiopia (0 9024Ö9 ;45 X). • 27 ' LITTLE-BG", BUCKLEY D R, CANT R, HENRY P W T, JEPPERISS A, MATHER J D, '."STARK J'& YOUNG R N (1977) Land resources of the Bahamas: a summary •(O 9O24O9 58 l). 28 JENKIN R N, HOWARD W J, THOMAS P, ABELL TIB* DEANE E C (1977/ Fcrestry deyelopment prospects in the Imatong Central Forest Reserve, southern Sudan. Volume 1, Summary (O 902409 65 4)• Volume 2, Main report (0' 902409 66 2). ':29' "LAND RESOURCES DEVELOPMENT CENTRE CENTRAL NIGERIA PROJECT TEAM (edf.I D HILL . ; ' &'J' R D WALL (l978)Land resources of central Nigeria: agricultural development possibilities. Volume LA, Bauchi Plains, Executive Summary (O 902409 80 8). Volume IB, Bauchi Plains (O 902409 81 6). Volume 2A, ^ Jos Plateau, Executive'Summary (0 902409 82 4) . Volume 2B, Jos'Plateau ' : - (O ,902409:83 2). Volume 3A, Jema'a Platform, Executive Summary (0 902409 84 0). Volume 3B, Jema'a Platform (O 902409 85 9). Volume 4A, *Benue Valley, Executive Summary (O 902409 86 7). Volume 4B, Bènue Valley '••* ;(0 902409 87 5). -"Volume 5A, Kaduna Plains, Executive Summary (O 902409 88 3). ;: Volume 5B, Kaduna Plains (.0 902409 89 l). Volume 6A, Kano Plains, Executive Summary (O 902409 90 5). Volume 6B, Kano Plains (O 902409 91 3). •"•;. Volume 'lr An "atlas of resource maps(0 902409 92 l) TECHNICAL BULLETINS (ISSN 0309 - 64I6), 1 CARROLL D M & BASCOMB C L (1967) Notes on the soils of Lesotho (0 902409 53 0). *2 PIGGOTT C J (1968) A soil survey of Seychelles (O 902409 00 X). 3 WILLIAMS J B (1978) Soil water investigations in The Gambia (O 902409 79 4). 4 WALL J R D, HANSELL J R P, CATT J A, ORMEROD E C, VARLEY J A & WEBB I S (1979) The soils of the Solomon Islands (O 902409 93 X). LAND RESOURCE BIBLIOGRAPHIES (ISSN 0309 - 1643) 1 POSNETT N W & REILLY P M comp. (l97l) Bahamas (O 903359 05 7). 2 POSNETT N W, REILLY P M & WHITFIELD P comp. (l97l) Nigeria. Volume 1 (0 903359 07 3). Volume 2 (O 903359 08 l). Volume 3 (0 903359 09 X). 3 POSNETT N W & REILLY P M comp. (1973) Belize (British Honduras) (0 902409 10 7). 4 POSNETT N W & REILLY P M comp. (1973) Fiji (0 902409 11 5). 5 GREENWAY M E, POSNETT N W & REILLY P M comp. (1974) New Hebrides and New Caledonia (0 902409 12 3). 6 REILLY PM comp. (1974) Nepal (O 902409 19 08). 7 POSNETT N W & REILLY P M comp. (1975) Solomon Islands (O 902409 24 7). 8 REILLY P M comp. (1976) Sabah, Malaysia (0 902409 36 0). 9 POSNETT N W & REILLY P M comp. (1977) Zambia (O 902409 43 3>. 10 REILLY P M comp. (1978) Ethiopia (0 902409 76 X). 11 REILLY P M comp. (1978) Yemen Arab Republic (O 902409 77 8) 12 POSNETT N W & REILLY P M comp. (1978) Dominica (o 902409 78 6). * Out of print