FARM MANAGEMENT HANDBOOK OF KENYA

VOL. II

– Natural Conditions and Farm Management Information –

ANNEX: – Atlas of Agro - Ecological Zones, Soils and Fertilising by Group of Districts –

Subpart A2 Nyanza Province Siaya County This project was supported by the German Agency for Technical Cooperation (GTZ), since 2011 it is GIZ = Gesellschaft für Internationale Zusammenarbeit (German Society of International Cooperation)

Farm Management Handbook of Kenya

VOL. I Labour Requirement, Availability and Costs of Mechanisation

VOL. II Natural Conditions and Farm Management Information

Part II/A WEST KENYA Subpart A1 Western Province Subpart A2 Nyanza Province

Part II/B CENTRAL KENYA Subpart B l a/b Rift Valley Province, Northern (except Turkana) and Southern Part Subpart B2 Central Province

Part II /C EAST KENYA Subpart C1 Eastern Province, Middle and Southern Part Subpart C2 Coast Province

VOL. III Farm Management Information - Annual Publications were planned. The idea changed to Farm Managament Guidelines, produced by the District Agricultural Offices annually and delivered to the Ministry in April

VOL. IV Production Techniques and Economics of Smallholder Livestock Production Systems

VOL. V Horticultural Production Guidelines

Publisher: Ministry of Agriculture, Kenya, in Cooperation with the German Agency for Technical Cooperation (GTZ) VOL. II is supplemented by CD-ROMs with the information and maps in a Geographical Information System. Additionally there will be wall maps of the Agro-Ecological Zones per district group (= the former large districts) for offices and schools.

Layout by Mike Teucher, Trier, Germany. FARM MANAGEMENT HANDBOOK OF KENYA VOL. II

Annex: - Atlas of Agro - Ecological Zones, Soils and Fertilising by Group of Districts in Nyanza Province -

Subpart A2

Siaya County

by Dr. Ralph Jaetzold Prof. emeritus of Geography, University of Trier / Germany

Helmut Schmidt Former Farm Management Research Officer from the former German Agricultural Team of the GTZ in the Ministry of Agriculture, Nairobi

Dr. Berthold Hornetz Prof. of Agricultural Geography, University of Trier / Germany Dr. Chris Shisanya Prof. of Agroclimatology, Dept. of Geography Kenyatta University, Nairobi Contributions to the 1st Edition by: C.M. Kang´e & J.G.M. Muasya – assessment of farm management data; Dr. Mechthild Kronen – soil requirements list; Prof. Dr. H. Kutsch – computing of crop-water relations for yield prob- abilities; F.N. Muchena, B.J.A. van der Pouw, W. Siderius and W.G. Sombroek – basic soil maps; H. Ritz – district climate tables; R. Swoboda – execution of Small Farm Survey; C.G. Wenner & S.N. Njoroge – soil conservation; W. Zettelmeyer – computing farm data. Additional Contributions to the 2nd Edition by: Dr. J. Ahenda & P. M. Maluku, KEPHIS; G. Awinyo (GIZ) – as- sisting R. J. & digitizing of soil maps into GIS; Th. Buettel – support by analyzing remote sensing data; M. Fiebiger – rainfall data analysis, probability calculations, yield probabilities by simulation programs; B. Girkens - final comput- erized drawing of maps in GIS and other maps; Heike Hoeffler – project coordination in GIZ Nairobi; Ph. Karuri – as- sistance in the Farm Survey; Ruben Kempf – typing and layout; Elizabeth Kimenyi & Anne Njoroge – coordination of farm survey; Z. Mairura, Senior Ass. Dir. of Farm Business Subdivision; S. N. Maobe (KARI); N. M. Maweu (KARI); Susanne Meissner - water availability & requirement diagrams, typing; M. Mueller – calculation and diagrams of grow- ing periods, ENSO influence; Dr. Anne W. Muriuki & J.N. Qureshi – soil and fertiliser recommendation maps and information; Francis Muthami (GIZ); Dr. Dorothy Mutisya and Dr. J Ochieng – crops and fodder list; Birgit Schmidt – basics for maintaining and regaining soil fertility; Joshua Shivachi & Ch. R. Wambongo– analysing the Farm Survey data using SPSS software; M. Teucher - final computerized drawing of soil and fertilizer maps; Dr. Lusike Wasilwa – horticult. part of the crop list; J. Wieczorek – computerization of maps in GIS; tables and diagrams. PREFACE TO THE ATLAS The internet and CD versions of the handbook have technically a reduction of details: The most important information, the maps, are due to reduction of the 24 MB to the CD-size of 6 MB, not well readable (esp. formulas of the AEZ Subzones and of the soils). Therefore we prepared additional Atlas- CDs for each group of districts, containing the maps of Rainfall, Agro - Ecol. Zones and Subzones, Soils, anhd Fertilizer Recommendations together with the legends. These maps are produced as pdf-files and can be zoomed for easy reading.

ACKNOWLEDGEMENT for the Support to the First Edition In compiling this Handbook, we have relied on the support of many officers from a variety of institutions too numerous to mention, who made available their data and experience. We would like to thank them for their invaluable assistance. I would also like to thank my colleagues, the Research Officers, the District Land and Farm management Officers, for their cooperation, and a special thank you to those who typed the draft edition. Our particular thanks go to Prof. Dr. Ralph Jaetzold, University of Trier, for his selfless support in compil- ing this handbook and for his assessment of the natural conditions including land and population. His deep understanding of the needs of agricultural extension officers and farmers was a great asset. Our thanks also to Dr. H. Kutsch, University of Trier, who computerized a large and complex amount of information involved in establishing the AEZs. Many thanks also to the staff of the Geographical Department of the University of Trier, Germany, for their major effort in drawing up maps of outstanding quality, the centrepiece of the work.

Helmut Schmidt Farm Management Research Officer Nairobi, May 1982

ACKNOWLEDGEMENT for the Support to the Second Edition In revising this Handbook, various personalities and institutions were relied upon to provide the necessary data required to update the previous data sets. In this regard, we would like to sincerely thank them for their invaluable input in the exercise. Special thanks go to the Ministry of Agriculture staff who undertook the Farm Surveys to elucidate on the fundamental changes that have taken place in farming at the household level. We are indeed very grateful to the people of Germany, who despite their limited financial resources, have continued to support Kenya. Of importance here is the German Agency for Technical Cooperation (GTZ) and the German scientists who have been working for Kenya over the years. Last but not least, thanks to Mr. Reimund Hoffmann, the PSDA Coordinator, Nairobi, whose office ably managed the Handbook revision project.

Prof. Dr. Chris Shisanya Elizabeth Kimenyi Professor of Agroclimatology Assistant Director of Agriculture Dept. of Geography FMD, MOA Kenyatta University, Nairobi Kenya Nairobi, January 2009 Nairobi, January 2009

We want to thank very much also Mr. Zachariah Mairura, Deputy Dir. of Agri-Business Dep., for his en- gaged support of our inquiries in the districts 2009 and 2010.

Prof. em. Dr. Ralph Jaetzold Prof. Dr. Berthold Hornetz Retired Professor of Geography Professor of Agricultural Geography University of Trier, October 2010 University of Trier, October 2010 PREFACE to the Second Edition

Institutional memory is of paramount importance for planning and development. For any research or agri- cultural extension to be successful, information on the natural farming potential is equally important.

In an effort to consolidate research - extension work of many years, the first edition of the Farm Manage- ment Handbook (FMHB) of Kenya Vol II (Natural conditions and farm management information), which described the conditions of the Kenyan farming community at that time, was produced in 1982/83. The handbook was in three parts i.e.:

A – for Western Kenya (Western and Nyanza provinces) B – for Central Kenya (Central and Rift Valley provinces). C – for Eastern Kenya (Eastern and Coast provinces)

For more than two decades, the handbook has proved very valuable to researchers, planners, extensionists, developers etc. This is a document that has been sought for enormously and hence the need to revise it in order to accommodate the changes that have taken place in our country since the production of the first edition. Some of these include: changes in the administrative boundaries, opening up of new farming areas due to population pressure, etc.

This second edition has been produced on the basis of Provincial administrative boundaries for the six Provinces i.e. Western, Nyanza, Rift Valley, Central, Eastern and Coast. The information will be availed in hard copies and in CD – ROMS to facilitate updating any future changes.

It is not possible to acknowledge the contribution of all the individuals who made this edition a reality but I need to mention the following individuals:

Thanks to the Ministry of Agriculture officers, especially the Farm Management Division officers at the headquarters (Mrs. E.W. Kimenyi, Mr. F.N. Nderitu, Mrs. H.W. Njoroge, Mrs. A.W. Njoroge, Mrs. A. W. Wanyama, Mr. P.T. Karuri and most engaged Mr. Z. Mairura), and the District staff, for their selfless contribution; Prof. Dr. Chris Shisanya, leader of the revision team, for his tireless efforts and guidance; Prof. em. Dr. Ralph Jaetzold for his enormous knowledge on the definition of the agroecological zones and his great contribution to their mapping; George Awinyo (German Technical Cooperation (GTZ) – Private Sector Development in Agriculture (PSDA)) for his expertise and contribution in the area of Geographical Information Systems (GIS).

I also wish to thank the GTZ who have facilitated the production of this edition both financially and by the use of their personnel, specifically the late Prof. Werner van der Ohe who supported the idea of the revision, and Mr. Reimund Hoffmann (GTZ – Team Leader Private Sector Development in Agriculture PSDA), for supporting and taking up the task to completion.

Dr. Wilson Songa, OGW AGRICULTURAL SECRETARY Nairobi, May 2009

SIAYA GROUP 1

3.4 SIAYA GROUP OF DISTRICTS

CONTENTS District Page

3.4.1 Natural Potential (R. Jaetzold et al.) 3 Introduction (R. J.) 3 Table 1: Rainfall Figures 4 Average Annual Rainfall Map (R. J.) 5 Table 2: Climate in the Agro-Ecological-Zones 7 Map of 66% Reliability of Rainfall of First Rainy Season (R. J.) 8 Map of 66% Reliability of Rainfall of Middle Rains and Second Rainy Season (R. J.) 9 Agro-Ecological Zones and Subzones Map (R. J.) 10 Agro-Ecological Zones and Subzones (= Legend to the AEZ Map), with Land Use Potentials and Water Availability & Requirement Diagrams (R. J. & B. Hornetz) 11 Soil Map (R. J. & KSS) 16 Soil Distribution, Fertility and Major Characteristics (R. J. & W. Siderius) 17 Legend to the Soils Map (R. J. & KSS) 17 3.4.2 Population and Land (C. A. Shisanya, R. Jaetzold & Central Bureau of Statistics) see big Vol. A2 3.4.3 Agricultural Statistics (R. Jaetzold, CBS & Min. of Agr.) see big Vol. A2 3.4.4 Farm Survey (Min. of Agr., C. A. Shisanya & R. Jaetzold) 22 Table 12: Farm Survey Areas in Siaya Group of Districts 23 Siaya Group of Districts: Farm Survey Areas Map (R- Jaetzold) 24 3.4.5 Introduction to the Actual Land Use Systems and Potential Intensification by Better Farm Management (C. A. Shisanya & Min. of Agr.) 25 Tables 15 a-g: Increase of Yields by Better Farm Management 27 LM 1 l^m i of the Lower Midland Sugarcane Zone 27 LM 2 l^(m/s) i of the Lower Midland Marginal Sugarcane Zone 29 LM 3 m^(s/vs) of the Lower Midland Cotton Zone 31 LM 3 m + (vs/s) of the Lower Midland Cotton Zone 33 LM 3 m + (vs) of the Lower Midland Cotton Zone 35 LM 4 m/s + (vu) of the Marginal Cotton Zone, Soil Unit Ul VC 37 LM 4 m/s + (vu) of the Marginal Cotton Zone, Soil Unit VXC 39 3.4.6 Fertiliser and Manure Recommendations for Important Agro-Ecological Units 41 Maps of Important Agro-Ecological Units & Fertiliser Recommendations (R. Jaetzold) 43 Tables 16 a–f: Fertiliser and Manure Recommendations (B. Hornetz) 44 LM 1 l^m i and LM 2 l^(m/s) i, UI D 1 &/ 2 of the two Sugarcane Zones 44 LM 2 l^(m/s) i & l/m^(s/m) and LM 3 m/l^(s), UmV & Ul V 1 of the Marg. Sugarcane Zone and Cotton Zone 46 LM 3 m + (vs/s), and LM 4 (m/s) + (vu), SA 2 of the Swamp Area in the Cotton Zone 48 SIAYA GROUP 2

LM 1 l^1^m i and LM 2 l^(m/s) i or l/m^(s/m), UlG 2 & UlY 1 of the Marginal Sugarcane Zone 50 LM 3 m/l^(s) & m + (vs/s) and LM 4 (m/s) + vu, Ul IC & Ul VC of the two Cotton Zones 52 3.4.7 Final Statements 54 Table 17: Basic Needs of a Rural Family 55 Table 18: Land Requirements for the Basic Needs 55 SIAYA GROUP 3

3.4.1 NATURAL POTENTIAL

INTRODUCTION

The area systematically shows the typical zoning of West Kenya: It is dry near Lake Victoria, and wet about 50 km away from there, with many transitions in between. The reason is the increase of rainfall due to local convergence of the daily lake winds with the South-east passat being in a generally low pressure area over the heated uplands. Thus, annual average rainfall increases from 800 mm at the lake shore to 2000 mm near the border of Kakamega. Therefore, it is understandable that the agro-ecological zones extend from a poor Livestock-Millet Zone to a good Sugar cane Zone. The contrasts in the zones of 66% rainfall probability1) for the cropping seasons are even higher, in the first rainy season from 350 mm to 900 mm, and in second one from 50 mm to 800 mm! For this reason, maize cultivation is very risky near the lake during the first rains and impossible during the second ones. Both rains are well distinguishable up to 25 km away from the lake (see Diagram Usigu Sub-Health Centre), although the peaks are not very well pronounced. Therefore, Katumani maize is not advisable in the dry zones, because it needs a pronounced peak of water supply to yield well. Sorghum and millets do better there (possibilities for sorghum are included, of course, in the Livestock-Millet Zone, too). In the better Cotton Zone, two crops of med. mat. maize are possible. In the more unreliable second rains, some fields should be planted with less demanding local maize varieties and with sorghum to bring down the risk. The start of the second rainy season is somehow difficult to define the more we approach the northeastern part of Siaya district. This is because of the middle rains: They are becoming bigger as a result of the convergence mentioned above. The advantage is, that planting and growing may continue there from one season to the other. In the Cotton Zone there are still chances for development with additional irrigation and swamp cultivation in the bottomlands, apart from the difficulties which the Yala Irrigation Scheme has faced. In the two Sugar Cane Zones, the rainfall decreased during the last 30 years at about 10-20%; around Akala the decrease was even more severe, from 1615 mm annual average to 1248 mm. This is the lower limit for sugar cane, it means the decrease is endangering the land use potential. Apart from the hope that it is a short term variation only or looking fatalistic to the climatic change, it is partly man made, and this cause can be avoided: Overuse of land has hardened the soil and increased runoff. This water is almost completely lost for evaporation and transpiration, the starting process of the tropical rainfall cycle. The soil situation is not good. The most fertile soils occur mainly in the climatically less suitable zones. Serious problems are caused by leached soils of low fertility if humus is lost. Soil conservation must start early, and compost as well as manure are essential especially in the wet areas and on soils with murram cuirass in shallow depths. Nematodes are another reason why climatically possible yields are not yet reached here. The great contrasts in the annual average rainfall and in the 66% reliability of rainfall can also be seen in the 60% reliability of the duration of the growing period (see Climate Table). The Marginal Cotton Zone (LM 4) only has a growing period of 130 days followed in the 2nd rainy season by a less than 45 day period; the Sugar Cane Zone (LM 1), however, has 200 or more days during the 1st rainy season and 120-130 days during the second one; these figures are the minimum in 6 out of 10 years. Near Lake Victoria the annual average temperature is about 22.8°C – in the northeastern part of the district it is 21°C. Humidity of the air is relatively high. For the entire district, evaporation is 1800-2000 mm per year.

1) 66% means that the amounts will be reached or surpassed normally in 10 out of 15 years. SIAYA GROUP 4

TABLE 1: RAINFALL FIGURES from selected typical stations having at least 15 years of records

Agro-Ecol. Annual Monthly rainfall in mm No. and Name of Zone and Kind of rainfall altitude Station Subzone records mm J F M A M J J A S O N D

8934031 Yala, St. Mary’s LM 1 Average 1838 68 95 152 262 260 132 106 155 148 131 136 104 1465 m School l ^ m i 66%1 1635 37 80 136 250 244 124 97 140 132 120 118 78 8934059 Oholo, LM 1 Av. 1718 65 71 139 275 251 114 113 144 163 148 138 97 1219 m Chief’s Camp l ^ m i 66% 1656 47 44 88 175 210 66 77 133 101 106 102 54 8934127 Ukwala, LM 2 Av. 1527 54 93 154 244 190 80 67 118 138 165 150 74 1256 m Distr. Office l ^ (m/s) i 66%2 1375 30 70 105 185 138 55 45 70 93 105 110 55 8934140 Kadenge Yala LM 3 Av. 1139 70 49 124 186 146 45 50 65 82 103 145 73 1167 m Swamp m ^ (s/vs) 66% 1081 40 43 81 124 91 26 33 40 52 73 91 54 8934141 Malanga LM 1 Av. 1735 69 82 159 281 243 102 94 172 157 133 144 100 1524 m Chief’s Camp l ^ m i 66% 1643 38 54 105 189 169 66 60 112 101 87 104 69 8934153 Ujimbe LM 1 Av. 1596 59 67 159 220 205 91 115 159 155 139 137 89 1524 m Ochiengs Farm l ^ m i 66% 1515 39 44 103 153 134 60 73 101 100 85 60 60 9034021 Usigu LM 4 Av. 977 56 66 108 151 129 47 32 44 32 49 101 81 Sub-Health (m/s) + vu 66% 736 37 20 65 84 71 30 17 33 24 30 78 51 1234 m Centre Ongielo LM 3-4 Av. 1079 42 62 125 196 132 67 55 65 72 64 116 83 9034022 Asembo 1137 m Disp. (m/s) + (vs) 66%2 957 9034036 Bondo Water LM 3 Av. 1139 54 52 119 176 130 64 59 76 89 114 125 83 1219 m Supply m ^ (s/vs) 66% 1063 42 27 87 108 90 41 39 48 56 81 102 52 9034037 Akala LM 2 Av. 1248 57 72 142 239 205 87 66 104 116 126 150 83 1220 m Health Centre l ^ (m/s) i 66% 990 37 51 87 147 149 51 32 61 70 56 111 47 9034104 Nyangoma LM 4 Av. 993 59 58 116 177 133 51 35 63 55 68 124 54 1219 m Catholic Miss. (m/s) + vu 66% 935 41 39 79 114 92 40 24 43 37 47 85 35

1 These figures of rainfall reliability should be exceeded normally in 10 out of 15 years. 2 Estimate by correlation, or not calculated because not enough years available to GTZ. SIAYA GROUP 5 SIAYA GROUP 6 SIAYA GROUP 7

TABLE 2: Climate in the agro-ecological zones

60% reliability of cereal and Ann. 66% reliability 2 1 legumes growing periods in Agro- mean Ann. av. of rainfall in mm days Altitude tempera- Ecological Subzone rainfall 1st rainy Middle r. & 1st rainy Middle in m 3 Zone ture in mm season 2nd rainy s. season rains & Total 4 in °C F. – Jy. Aug. – D. or F. – Jy. 2nd rainy or less less or less season UM 1 Coffee-Tea p or l ^ m 1500-1570 21.0-20.5 1600-1900 750-950 600-800 190 or more 130-1605 ca. 350 Zone LM 1 p or two Very small, almost similar as l ^ m i Lower Midland Sugar Cane Zone l ^ m i 1300-1500 21.8-20.9 1500-1900 750-950 600-800 190 or more 130-1505 320-340 LM 2 l ^ (m/s) i 1450-1600 700-800 500-680 180 or more 110-120 300-310 Marginal Sugar 1200-1350 22.3-21.5 Cane Zone l/m ^ (s/m) i 1400-1500 650-700 450-550 170 or more 105-120 275-290 LM 3 m/l ^ (s) 1220-1390 490-650 350-500 155-165 80-90 235-255 Lower m ^ (s or s/vs) 1140-1250 22.7-22.0 1110-1220 480-600 340-470 140-155 75-85 215-240 Midland Cotton Zone m + (vs/s or vs) 1020-1100 420-540 200-330 135-145 45-75 LM 4 no reliable Marginal (m/s) + (vu) 1135-1200 22.7-22.3 890-1020 350-480 unreliable 125-135 growing Cotton Zone period LM 5 Lower Midland 1135-1180 22.7-22.4 Very small, unimportant “ 105-120 “ Livestock- (s/m) + (vu) Millet Z.

1 Amounts surpassed normally in 10 out of 15 years, falling during the agro-humid period which allows growing of most cultivated plants. 2 Amounts surpassed normally in 6 out of 10 years which gives a more realistic picture to the farmer. 3 More if growing cycle of cultivated plants continues into the period of middle rains, and even of the 2nd rainy season. 4 Only added if rainfall continues at least for survival of most long term crops (>0.25 PET) from 1st to 2nd rainy season. 5 The alternatives are depending if middle rains are combined with first or second rainy season. SIAYA GROUP 8 SIAYA GROUP 9 SIAYA GROUP 10 SIAYA GROUP 11

AGRO-ECOLOGICAL ZONES AND SUBZONES - Introduction

These two districts belong by its agro-ecological zonation to the system of the Western Province: from the semiarid zone LM 4 near the Lake Victoria to the permanent humid zone LM 1 towards the inland, crossing the transitional zones LM 3 and 2 which stretch also parallel to the lakeshore. At the lake shore there seems to be even a small strip of zone LM 5 although it cannot be proved by rainfall records. But the daily wind circulation of rising air inland causing rain, and falling dry air near the cool lake let us assume it. This system is especially active during the second half of the year making the 2nd rainy season in more than 40% of the years not long and strong enough for a reliable minimum growing period. Therefore it is named vu = very uncertain. The other introductory statements about fertilising and manuring as well as checking in the crop list many more than the mentioned varieties here, are the same as in the other district groups. Mainly it must be remembered that the given percentages of optimal yields are climatically. Suitable soils, optimal fertilising as well as manuring and good crop husbandry are necessary. But in some Agro-ecological units, like LM 2 l ^ (m/s) i on orthic ferralsols with petroplinthite, the soil conditions are so poor that hybrid maize (H 622) yields even with fertilisers only 30% of the optimum instead of >60% which are climatically possible (see T. 16e). Striga, stem borer and nematodes are severe yield reducers, too.

AGRO-ECOLOGICAL ZONES AND SUBZONES (Legend to the Map) UM = UPPER MIDLAND ZONES UM 1 = Coffee-Tea Zone Very small, see Kakamega Group of Districts LM = LOWER MIDLAND ZONES LM 1 = Lower Midland Sugar Cane Zone LM 1 = Lower Midland Sugar Cane Zone with permanent cropping possibilities, dividable in two variable p or cropping seasons two Very small, see Kakamega Group of Districts LM 1 = Lower Midland Sugar Cane Zone with a long cropping season followed by a medium one and l ^ m i intermediate rains (see Diagram Oholo) Very good yield potential (av. >80% of the optimum) 1st rainy season, start norm. F. but reliable beg. of March: Early & med. mat. sorghum; m. mat. sunflower like Kenya Fedha, Shaba, H 893 or 894; m. mat. soya beans like Hill; sweet potatoes, yam beans1 Whole year , best planting time March: Pawpaws, guavas; New Zealand spinach, spinach beet (both biennal) Good yield potential (av. 60-80% of the optimum) 1st rainy season: M. mat. maize like H 622, 623 or 625 - 29 (but see introd.) late mat. sorghum like E 1291 (for stock feed), finger millet; rice; m. mat. beans like Cuarentino2, pigeon peas (March-F.); yellow yams (F.-O./N.); sweet pepper, kales, Chinese cabbage, spinach, cabbage, chillies, egg plants (to 2nd rainy season), pumpkins 2nd rainy season , start undistinctly middle of Aug.: Maize H 513 - 518, m. mat. sorghum; e. mat. beans, cowpeas, sweet potatoes; m. mat. soya beans, e. mat. sunflower like HS 345; kales, Chinese cabbage, spinach, onions Whole year: Sugar cane, bananas (nematodes danger) 3, tea in upper places (70-80%, but medium to low quality), Robusta coffee 3, avocadoes, late mat. cassava SIAYA GROUP 12

mm mm LM 1 l ^ m i Nr.: 8934059 Oholo Chief‘s Camp 100 0°12‘ N 34°21‘ E 1216m 32 y. up to 1976 100

stored surplus

50 50

0 0 F M A JJM A JDNOS 880 590

Average rainfall per decade rainfall surpassed in 10 out of 15 years Approx. pot. evapotranspiration of a permanent crop (bananas) Approx. pot. evapotranspiration of m./l. mat. maize like H 623 Approx. pot. evapotranspiration of m. mat. maize like H 515 880 Rainfall per indicated growing period, surpassed in 10 out of 15 years

Fair yield potential (av. 40-60% of the optimum) 1st rainy season: Cotton (medium quality) 2nd rainy season: Maize H 623, finger millet; late mat. groundnuts like Mwitunde (in light soils) and late mat. bambarra groundnuts (in light soils, even in poor ones); cabbage Whole year: Mangoes, citrus (for both danger of fungus diseases); taro Pasture and forage Around 0.5ha/LU on sec. pasture where originally there has been a moist submontane forest; down to 0.1 ha/LU feeding Napier (Bana) grass, banana leaves and Siratro (start of planting middle - end of Feb.: fair yields, start beginning - end of March: good yields). Other forage see Table XI. LM 2 = Marginal Sugar Cane Zone LM 2 = Marginal Sugar Cane Zone l^(m/s) i with a long cropping season followed by a (weak) medium to short one and intermediate rains Very good yield potential 1st rainy season, start norm. mid F. to b. of March: Early mat. sorghum like Serena (March – June); m. mat. sunflower like Kenya Fedha, Shaba, H 893 or 894, e. mat. soya beans like Magoye or Black Hawk; sweet potatoes, onions, yam beans1, e. mat. cassava Whole year: Pawpaws Good yield potential 1st rainy season: M. mat. maize like H 623, late mat. sorghum like E 1291 (stock feed), finger millet; m. mat. beans2 like Cuarentino, pigeon peas (March-F.), late mat. rosette resistant groundnuts like Mwitunde (in light soils); cotton (med. quality); sweet pepper, tomatoes, cabbages, kales, roselle 2nd rainy season , start Aug.: Bulrush millet, m. mat. sorghum, ratoon sorghum1 (S.-Aug.); e. mat. beans like Rosecoco (GLP 2), green grams; onions, kales, tomatoes Whole year: Bananas (nematodes danger) 3, pineapples, sisal, New Zealand spinach & spinach beet (both also annual) Fair yield potential 1st rainy season: rice, bambarra groundnuts (in light soils, even in poor ones), cowpeas; tobacco 2nd rainy season: Maize H 513 - 518; pigeon peas (Sept.-July), cowpeas, m. mat. groundnuts like Serere 116; sweet potatoes; simsim; cabbages; cotton (July-Feb.) 6; e. mat. sunflower like HS 345 Whole year: Sugar cane (on less suitable soils marginal), Robusta coffee, citrus, mangoes SIAYA GROUP 13

Pasture and forage 0.5-0.7 ha/LU on high grass savanna with Hyparrhenia and Panicum dominating; down to about 0.15 ha/LU feeding Napier (Bana) grass and banana leaves. Siratro and Desmodium for soil and pasture improvement, Leucaena additionally (and others, see T. XI). LM 2 = Marginal Sugar Cane Zone l/m ^ with a long to medium cropping season followed by a (weak) short to medium one and (s/m) i intermediate rains Small and transitional. Crop potential like LM 2 l ^ (m/s) i but m. mat. sorghum in 2nd rainy season and bananas only fair, maize H 513 - 518 in 2nd rains and sugar cane (also on good soils) only marginal. Ratooning sorghum 1st to 2nd rains good. Stocking rates ca. 10% less. LM 3 = Lower Midland Cotton Zone LM 3 = Lower Midland Cotton Zone m/l^(s) with a medium to long cropping season followed by a (weak) short one Transitional strip, potential see Kisumu District LM 3 = Lower Midland Cotton Zone m^(s/vs) with a medium cropping season followed by a (weak) short to very short one Good yield potential 1st rainy season, start norm. begin of March: M. mat. maize like H 513 - 518 (~60%), e. mat. Sorghum like Serena (70-80%), e. mat. millets; m. mat. beans, green grams, cowpeas, groundnuts (in light soils); simsim4; sweet potatoes; cotton, e. mat. soya beans like Hawk, m. mat. sunflower like Kenya Fedha or Shaba; chick peas (on heavy black soils), castor7; tomatoes, onions, muskmelons, butternut 2nd rainy season, start norm. e. of Aug.: Simsim, green grams, tomatoes Whole year, best pl. time March: Cassava (~60%), sisal Near swamps with water regulation resp. add. irrigation: rice, bananas (on dams), Chinese cabbage (on ridges) and other vegetables Fair yield potential 1st rainy season: M. mat. maize like H 623, finger millet (50-60%); pigeon peas (March-F.), tobacco (on sandy soil, higher places); yam beans 2nd rainy season: E. mat. maize, early mat. proso millet (O.-N.), ratoon of sorghum, e. mat. sorghum, e. mat. bulrush millet (bird rejecting awned var. best)1; Katheka beans, e. mat. bambarra groundnuts (in light soils, also in poor ones); sweet potatoes in swampy places; cotton (July-F., ~40%)6 Whole year: Pawpaws, mangoes, citrus, pineapples Pasture and forage 0.7-1.0 ha/LU on mixed savanna with star grass (Cynodon dactylon); down to about 0.18 ha/LU feeding Napier grass, Bana, Desmodium (planting between maize catches Striga) or Stylosanthes (also for soil improvement), Leucaena additionally LM 3 = Lower Midland Cotton Zone m + (vs/s with a medium and a (weak) very short to short or very short cropping season or vs) Good yield potential 1st rainy season like LM 3 m^(s/vs) except cotton, m. mat. maize like H 513 & 515, m. mat. sorghum (60-70%), butternut, Jatropha Whole year: Sisal Fair yield potential 1st rainy season, start norm. m. of March: Maize H 623 (40-50%), m. mat. finger millet like Lanet FM 1; cotton; pigeon peas (March-F.) 2nd rainy season, start norm. Sept.: V. e. mat. proso millet Serere I, in subzone vs/s e. mat. foxtail millet Se 285, v. e. mat. sorghum(~40%); green grams, simsim; sweet potatoes near water Whole year: Cassava

Pasture and forage 0.9-1.2 ha/LU, down to ca. 0.25 ha/LU feeding Bana grass, Desmodium and Stylosanthes, some Leucaena tricandria, too SIAYA GROUP 14

mm mm LM 4 m/s + (vu) 100 100 Nr.: 9034021 Usigu, Sub-Health Centre 0°05‘ S 34°08‘ E 1231m

50 50

0 0 F M A JJM A JDNOS 4 0 0

Average rainfall per decade rainfall surpassed in 10 out of 15 years Approx. pot. evapotranspiration of a permanent crop (sisal) Approx. pot. evapotranspiration of e. mat. sorghum Approx. pot. evapotranspiration of e. mat. maize Approx. pot. evapotranspiration of cotton 400 Rainfall per indicated growing period, surpassed in 10 out of 15 years

LM 4 = Marginal Cotton Zone LM 4 = Marginal Cotton Zone with a medium to short cropping season and a very uncertain (weak) m/s + (vu) second rainy season (see Diagram Usigu) 1st rainy season, start norm. mid March: E. mat. sorghum like Serena (~60%), e. mat. foxtail or proso millet (60-70%); v. e. mat. beans like Katheka (~60%), green grams, cowpeas, chick peas (on heavy black soils); e. mat sunflower HS 345 (~60%), simsim Whole year: Sisal, Jatropha Near swamps: Like LM 3 Fair yield potential 1st rainy season: E. mat. maize like PH 1 or PH 4 (40-50%), e. mat. bulrush millet; grain amaranth1; pigeon peas (~40%); e. mat. sunflower, e. mat. soya beans like Nyala (40-50%), e. mat. groundnuts and e. mat. bambara groundnuts (both in light soils); tomatoes, onions; sweet potatoes near water Whole year: Cassava, mangoes

Poor yield potential 1st rainy season: Cotton, m. mat. maize 2nd rainy season: Simsim

Pasture and forage 1-2 ha/LU; Leucaena, Saltbush (Atriplex nummularia) and other palatable shrubs (see T. XI) to plant in order to improve fodder situation during dry season. LM 5 = Lower Midland Livestock-Millet Zone

LM 5 = Lower Midland Livestock-Millet Zone (s/m) + with a (weak) short to medium cropping season and a very uncertain (weak) second rainy season (vu) Very small on lakeside, potential see South Nyanza Group of Districts. Bulrush millet (bird rejecting awned variety)1 should be introduced. No protein crop necessary because of good fish supply. SIAYA GROUP 15

1 Crops written in italics are not yet common in Kenya 2 Should be intercropped with maize because of hail storm danger 3 Windbreaks against the daily winds from the lake, light shade and mulching or compost are necessary to re-establish the former forest eco-system, otherwise bananas and coffee grow poorly. Hardpan soils should be avoided 4 Planting towards the end of the long rains 5 Good for rotation because of its resistance against Striga spec. and nematodes. 6 Although nearly marginal, cotton is mainly planted in 2nd rainy season because of more labour availability. It can be interplanted in maize already during July. 7 Good for rotation because of its resistance against Striga and nematodes. SIAYA GROUP 16 SIAYA GROUP 17

SOIL DISTRIBUTION, FERTILITY AND MAJOR CHARACTERISTICS

Siaya and Bondo districts are mainly a peneplain of very old foldings (the Nyanzan System, more than 600 Mill. years old). Therefore a great variety of bedrocks are the base for many different soils but only a few are fertile by nature, and due to their age most of them are almost senile. Therefore they need improvement by man. The peneplain slopes very gently downward from northeast to southwest. The peninsula in the south is covered by old basic igneous rocks (basalts, andesites). The Phaeozems and Nitisols developed there have the highest fertility of the district group (Ul B 1, Ul B 5 and Ul B 7) but the climate is semi-arid. The other part with Nitisol is in the humid NE, but it is already so leached that it became a dystric one (Um D 1) with moderate fertility only. Most of the soils of the dominating lower level uplands are developed upon acid granites, sandstones or conglomerates which means low fertility. The central southwestern part is formed by intermediate igneous rocks. This would mean soils of moderate fertility but due to the age it came to two different soils: on interfluves, shallow Ferralsols over petroplinthite (“murram cuirass soils”) with low fertility plus other limitations, and fertile Nitisols on the valley sides. In the valley bottoms in the southern parts, the soils are mainly poorly drained, often mottled and subject to flooding. Along the Yala river young alluvial soils are found. They usually vary greatly in texture and colour over short distances, but may have a relatively high natural fertility before the river enters the Yala Swamp where humic Gleysols and dystric Histosols dominate, which need special amelioration to be cultivated.

LEGEND TO THE SOIL MAP OF SIAYA GROUP OF DISTRICTS

1 Explanation of the first character(physiographie )

H Hills and minor scarps (hilly to steep; slopes predominantly over 16%; relief intensity up to 100 m per km (Minor Scarps) to 300 m (Hills); altitudes up to 2850 m in W-Kenya, here 1568 m)

F Footslopes (at the foot of Hills and Mountains; gently undulating to rolling; slopes between 2 and 16%; various altitudes)

U Uplands Um Lower Middle-Level Uplands (gently undulating to undulating; slopes between 2 and 8%; altitudes between 1200 and 2200 m, here 1300 – 1500 m) Ul Lower-Level Uplands (very undulating to undulating; slopes between 2 and 8%; altitudes between 1200 and 2100 m, here 1200 – 1400 m)

P Plains Pl Lacustrine Plains (almost flat to gently undulating; slopes between 0 and 5%; altitude approximately 1200 m; along Lake Victoria)

A Floodplains and River Terraces (almost flat to gently undulating; slopes between 0 and 5%; various altitudes; seasonally flooded or ponded)

B Bottomlands (flat to gently undulating; slopes between 0 and 5%; various altitudes; seasonally ponded)

S Swamps (almost flat; slopes between 0 and 2%; various altitudes; permanently waterlogged if not reclaimed)

V Minor valleys (V or U-shaped valleys; slopes mainly up to 16%, exceptionally up to 30%; width mainly 250- 500 m, up to about 1000 m; depth up to about 100 m; various altitudes SIAYA GROUP 18

2 Explanation of the second character (lithology) Plant nutrients in parent material: A Recent Alluvial Sediments from various sources Many B Basic Igneous Rocks (basalts, nepheline phonolites; older basic tuffs included Many D Mudstones and Claystones Few G Granites and Granodiorites Few I Intermediate Igneous Rocks (andesites, phonolites, syenites, etc.) Many V Undifferentiated or various Igneous Rocks Many X Undifferentiated or various Rocks Few to many Y Acid Igneous Rocks (Syenites, etc.) Few

3 Soil descriptions

HB 1 Somewhat excessively to well drained, very shallow to moderately deep, yellowish red to dark reddish brown, friable, gravelly sandy clay to clay; in many places with an acid humic topsoil; in places stony and rocky: dystric, eutric and humic CAMBISOLS and eutric REGOSOLS, partly lithic and stony phases, and LITHOSOLS, with Rock Outcrops

HGC Complex of: Somewhat excessively drained, shallow, stony and rocky soils of varying colour, consistency and texture: dystric REGOSOLS and RANKERS, with ferralic and humic CAMBISOLS, lithic, rocky and stony phases, LITHOSOLS and Rock Outcrops

FB 2 Well drained, very deep, dark red to dark reddish brown, friable clay: eutric NITISOLS

FG 1 Well drained, shallow to moderately deep, dark yellowish brown to reddish brown, friable, stony, sandy clay loam to gravelly sandy clay; in places with an acid humic topsoil or very shallow and rocky: ferralic, dystric and humic CAMBISOLS and orthic ACRISOLS, stony and partly lithic and rocky phases; with LITHOSOLS and Rock Outcrops

UmD 1 Well drained, very deep, red to dark red, friable clay: dystric NITISOLS

UmV 1 Well drained, very deep to extremely deep, dark red, friable clay, in places deep: eutric NITISOLS, with chromic LUVISOLS

Ul B 1 Well drained, extremely deep, dark red, friable clay; in places deep: eutric NITISOLS

Ul B 5 Moderately well drained, moderately deep to deep, (very) dark brown, firm clay; in many places slightly cal- careous and/or cracking clay; with a humic topsoil: haplic and verto-luvic PHAEOZEMS, partly lithic or pisocalcic phases

Ul B 7 Moderately well to imperfectly drained, deep, very dark grey to very dark greyish brown, mottled, firm, crack- ing clay; in places moderately deep over petroplinthite: vertic LUVISOLS, partly petroferric phase, with chromic VERTISOLS

Ul B 8 Well drained, shallow to moderately deep, reddish brown to dark reddish brown, firm clay; over petroplin- thite or rock: chromic LUVISOLS and ACRISOLS, petroferric and lithic phases

Ul BC Complex of: soils as in unit Ul B 1: eutric NITISOLS and: soils as in unit Ul B 8: chromic LUVISOLS and ACRISOLS, petroferric and lithic phases SIAYA GROUP 19

Ul D 1 Well drained, moderately deep to very deep, dark red to strong brown, friable clay; in many places shallow over petroplinthite: chromic and orthic ACRISOLS and rhodic FERRALSOLS, partly petroferric phases, and dystric phases, with dystric NITISOLS

Ul D 2 Well to moderately well drained, very shallow to moderately deep, yellowish red to strong brown, friable sandy clay to clay; over petroplinthite, pisoferric material or conglomerate rock: orthic ACRISOLS and ferralic CAMBISOLS, petroferric, pisoferric and lithic phases and LITHOSOLS

Ul G 1 Well drained, deep to very deep, yellowish red to strong brown, friable clay; in places moderately deep, over petroplinthite or rock; in places rocky: orthic ACRISOLS; with Rock Outcrops

Ul G 2 Well drained, moderately deep to deep, dark reddish brown to red, friable; stony, gravely sandy clay to clay; over petroplinthite or rock; in places shallow or rocky: orthic ACRISOLS; with orthic FERRALSOLS, stony and partly petroferric phases; with Rock Outcrops

Ul G 3 Well drained, shallow to moderately deep, dark yellowish brown to strong brown, friable sandy clay; over petroplinthite; in places very shallow, stony or rocky: orthic and ferralo-orthic ACRISOLS, petroferric and partly stony phase, with LITHOSOLS and Rock Outcrops

Ul I 1 Well drained, deep, red to dark red, friable clay; in places (mainly on interfluves) shallow to mod- erately deep over petroplinthite: Chromic ACRISOLS, partly petroferric phase

Ul IC Complex of: well drained, very shallow to moderately deep, dark red to strong brown, friable, gravelly clay to clay; over petroplinthite, pisoferric material or rock; in places stony: chromic and orthic ACRISOLS and dystric CAMBISOLS, petroferric, pisoferric or lithic phases and partly stony phases, and LITHOSOLS, partly stony phase

Ul V 1 Well drained, deep to very deep, yellowish red to strong brown, friable clay: chromic and orthic ACRISOLS

Ul V 2 Well drained, moderately deep to deep, reddish brown to dark red, friable to firm clay; over petroplinthite or pisoferric material: chromic LUVISOLS and ferralo-chromic ACRISOLS, petroferric and pisoferric phase

Ul V 5 Well drained, shallow, dark yellowish brown, gravelly clay to clay; over petroplinthite; in places very shallow and stony: orthic LUVISOLS and eutric CAMBISOLS, petroferric and lithic phases, partly stony phases, with LITHOSOLS and Rock Outcrops

Ul VC Complex of: well drained, very shallow to moderately deep, yellowish red to strong brown, friable, gravelly clay loam to clay of varying rockiness and stoniness; over petroplinthite or rock: chromic LUVISOLS and ACRISOLS and ferralic CAMBISOLS, petroferric and lithic phases, partly stony phases, with LITHOSOLS and Rock Outcrops

Ul X 5 Somewhat excessively to moderately well drained, shallow, dark brown to dark greyish brown, calcareous, silty clay loam to clay loam; over gravel or weathering rock; in places very shallow, stony or with a humic topsoil: calcaric and eutric REGOSOLS and calcic and eutric CAMBISOLS, with calcaric PHAEOZEMS, paralithic and partly stony phases, and with LITHOSOLS, partly stony phase

Ul X 9 Well drained, shallow, dark yellowisch brown to dark brown, friable to firm, gravelly clay to clay; over petroplinthite: orthic ACRISOLS, petroferric and lithic phase SIAYA GROUP 20

Ul Y 1 Well drained, moderately deep to deep, yellowish red to strong brown, friable clay; over petroplinthite or rock; in places shallow over petroplinthite or bouldery: orthic FERRALSOLS, partly petroferric or bouldery phase

Pl A 8 Poorly drained, deep to very deep, very dark grey, mottled, firm clay, with a thick acid humic topsoil; in places cracking clay: humic GLEYSOLS, with vertic GLEYSOLS

AA 1 Well to moderately well drained, deep, dark greyish brown to yellowish brown, friable, stratified, sandy clay loam to clay; in places mottled, firm clay; in places slightly saline or sodic; on river levees: eutric FLUVISOLS, with vertic FLUVISOLS and vertic and eutric GLEYSOLS, partly saline-sodic phases

AA 2 Imperfectly to poorly drained, deep, greyish brown to very dark grey, mottled, very firm, saline and sodic, cracking clay; in river backswamps: pellic VERTISOLS and vertic GLEYSOLS, saline and sodic phases

BX 2 Imperfectly to poorly drained, deep to very deep, greyish brown to very dark grey and black, mottled, firm to very firm clay to cracking clay; in places with a saline and sodic subsoil; slightly elevated parts of bottomlands: eutric GLEYSOLS and pellic VERTISOLS, partly saline-sodic phases

BXC 1 Complex of: imperfectly to poorly drained, deep to deep, very dark grey to brown, mottled, firm to very firm, sandy clay to cracking clay, in many places abruptly underlying a topsoil of friable sandy loam; in places saline and sodic: dystric PLANOSOLS, dystric and vertic GLEYSOLS and pellic VERTISOLS; partly saline-sodic phases

SA 2 Very poorly drained, very deep, dark grey to black, half ripe clay, with an acidic humic or dystric histic topsoil; in many places peaty: humic GLEYSOLS and dystric HISTOSOLS

SAC 1 Complex of: Imperfectly to poorly drained, deep to very deep, greyish brown to very dark grey and black, mottled, firm to very firm clay to cracking clay; in places with a saline and sodic subsoil: eutric GLEYSOLS and pellic VERTISOLS, partly saline-sodic phase and: Very poorly drained, deep, dark grey to black, half ripe clay, with a humic or histic topsoil; in many places peaty: mollic GLEYSOLS and dystric HISTOSOLS

VXC Complex of: Well drained, shallow to deep soils of varying colour, consistency and texture (on valley sides): CAMBISOLS, ACRISOLS and FERRALSOLS, partly lithic phases, with Rock Outcrops and: imperfectly to poorly drained, deep mottled soils with predominantly greyish colours, firm consistency and fine textures (in valley bottoms): GLEYSOLS, with VERTISOLS and HISTOSOLS

Notes for definitions (of underlined words): mollic Nitisols and chromo-luvic Phaeozems: soils are equally important mollic Nitisols, with chromic-luvic Phaeozems: Nitisols are prevalent in places: in < 30% of the area in many places: in 30-50% of the area predominantly: in > 50% of the area deeper subsoil: below 80 cm SIAYA GROUP 21

3.4.2 POPULATION AND LAND see main Volume Nyanza Province

3.4.3 AGRICULTURAL STATISTICS see main Volume Nyanza Province SIAYA GROUP 22

3.4.4 FARM SURVEY IN SIAYA GROUP OF DISTRICTS

The farm survey (FS 2004) was carried out in seven sites covering the AEZ´s LM 1-4 representing different Subzones (table 12): The data collected during the FS 2004 on various agricultural aspects are presented in Tables 13 a-g, while the cropping patterns reported are shown in Tables 14 a-g. The data in the Tables reveal the following key points: In the lower zones LM 3 & 4 of Bondo and Rarieda Districts, the farm sizes (Table 13 a, b, c & e) seem to be still above the poverty line (av. 1.78 ha) with 1.8, 2.4, 3.5 & 3.6 ha, except in Usenge where there are 0.82 ha only (Table 13 d) but fishing possibilities. In fact the 120 farms of these four survey areas are above average which is 1.45 ha only. But these four survey results are also with the number of persons above the average of 4.2 per household: 6.9, 8.5, 6.6 resp. 5.6 persons. Although this makes the bigger sizes partly understandable, it has to be considered a general problem of the inqiries: The bigger farmers are automatically preferred as the more important ones. Therefore, the general rural situation is worse than the tables show! Land shortage is a severe problem and intensification lays behind.The percentage of improved cattle is still very low, many farmers don´t have some. The figure was calculated just asa percentage of dairy from total cattle. The question for upgraded crossbreds could not be properly answered. The use of improved seed is between 20 and 40% only, the use of fertiliser almost zero and the application of manure reaches not even 10% of the amount necessary (all sample farms are below 5% average for annual crops). Insecticides and fungicides are also not used. It is evident, that in Bondo and Rarieda Districts there is a lot of scope for better farm management! The situation in Siaya and Ugenya Districts (mainly LM 1 & 2) is worse regarding the farm sizes and the number of improved cattle, a bit better with manure and much better in the application of fertiliser. The reason for that is poor soil and the sugarcane which needs it most, but the farmers get also the ready cash with it for the inputs. The high application of fertiliser for the food crops increases the danger of quicker exhaustion of the other, not given nutrients. This can already be noticed in comparison of the yields in Tables 15 a-g with the first farm survey 1977 in the first edition of the Farm Management Handbook. Altogether, the resource poor farmers in Siaya group of districts encounter numerous problems, which contribute to low crop and livestock productivity. These include: continuous cropping on less fertile land, little of the recommended manures, fragile easily erodible soils, poor crop and animal husbandry. Poor soil management practices, use of unimproved low yielding crop varieties and livestock breeds have culminated to low living standard. It is strongly recommended that farmers in this region embrace sustainable agriculture in order to increase the per capita land productivity.

Sustainable agriculture offers solutions to some of these aforementioned problems observed in the Siaya group of districts. These can be summarized as follows:

• Improved soil fertility: Conventional farming methods rely on artificial fertilizers to maintain fertility. Sustainable agriculture uses a range of techniques to maintain and improve soil fertility: organic fertilizers, mulching, cover crops, agroforestry, crop rotation and multiple cropping.

• Better pest control: Conventional farming uses chemical pesticides to control pests. These are expensive and often result in the emergence of new pests or the resurgence of the very pests they are trying to control. Sustainable agriculture instead uses integrated pest management approaches: a combination of natural enemies, crop rotations and mixtures and biological control methods. These methods cost less than the pesticides, and do not result in pest resurgence.

• Controlling erosion: Sustainable agriculture includes a palette of techniques to conserve precious topsoil and prevent it from being washed or blown away. These include using contour bunds, contour planting, check-dams, gully plugs, and maintaining cover crops or mulch to protect the soil from heavy rainfall.

• Water conservation: Water is scarce here in short rains of Zone LM 3 and 4, and drought is never far away. Sustainable agriculture conserves water in the soil through a variety of methods. Fortunately, many of these are the same as those used to control soil erosion. Because it conserves water and uses a variety of crops instead of just one, sustainable agriculture is less risky than conventional monocropping: it is more likely to produce food for the farm family even during a drought. SIAYA GROUP 23

• Reliance on local inputs: Farmers often do not realize the value of the inputs they have immediately to hand. They include manure from their animals (which very often is wasted in conventional systems), vegetation from roadsides and the field boundaries (used as mulch or to make compost), and local varieties of crops (many of which are ideally adapted to local conditions but which have been half-forgotten in the rush to adopt modern varieties).

• Indigenous knowledge: An important local input is the people’s own knowledge. Local people are experts on the plants, animals, soils and ecosystems they are surrounded by and on which they depend. Sustainable agriculture draws on this wealth of knowledge, and encourages local people to use it, test it, and promote what works best.

• Local organizations and initiative: Equally important are the energy and capacity of local people to organize and cooperate to solve their own problems. Unlike conventional extension agencies, organizations that promote sustainable agriculture spend at least as much time in helping farmers organize as they do in teaching farming technologies. Ironically, many sustainable agriculture approaches are very similar to the techniques traditionally used by farmers before the advent of “modern” farming. That does not mean, though, that sustainable agriculture turns its back on modern inputs or ideas. Many types of sustainable agriculture use modern high-yielding crop varieties and artificial fertilizers wherever appropriate.

TABLE 12: FARM SURVEY SITES IN SIAYA GROUP OF DISTRICTS Representative of the Dominating Agro-Ecological Zones, Subzones and Units

Agro-Ecological Unit Districts No. in Farm Survey Sites 2004 Kenya AEZone Subzone Soil Unit Maranda Division, Township Location, Ajigo Sub- 28 LM 3 m ^(s/vs) Ul V5 location Maranda Division, West Sakwa Location, Bondo West 29 LM 3 m +(vs/s) Ul I C Sub-location Maranda Division, West Sakwa Location, Nyawita- Bondo 30 LM 3 m + (vs) BX 2 Maranda Sub-location Usigu Division, West Yimbo Location, Usenge Sub- 31 LM 4 m/s + (vu)* Ul VC location Usigu Division, North Yimbo Location, Nyamonye 32 LM 4 m/s + (vu)* VXC Sub-location Ugunja Division, East Uholo Location, Sigomere Sub- 33 LM 1 l^m i Ul D 1 location Siaya Ugunja Division, Central Ugenya Location, Umala 34 LM 2 l^(m/s) i Ul D 1 Sub-location

*vu = very uncertain, it means a minimum growing period of at least 50 days occurs in less than 6 seasons out of 10.

Tables 13 a - g: ASSETS LAND USE, FARMING INTENSITY AND INPUTS see main Volume Nyanza Province Tables 14 a - g: CROPPING PATTERN see main Volume Nyanza Province SIAYA GROUP 24 SIAYA GROUP 25

3.4.5 INTRODUCTION TO THE ACTUAL LAND USE SYSTEMS AND POTENTIAL INTENSIFICATION BY BETTER FARM MANAGEMENT IN DOMINATING AGRO- ECOLOGICAL SUBZONES

The present situation and the future aspects of the seven dominating subzones of the large Agro-Ecological Zones LM 1-4 according to the Tables 13 & 14 a-g and the further Tables 15 a-g are here interpreted. In order to realize the main task of the farm management, the increase of production, a question targeting specifically the inputs used by farmers and resultant increase in yields was included in the Small Farm Survey questionnaire that was conducted. In each survey area the purposively sampled 30 farmers were divided into 3 groups: one group applying low inputs, a second one medium inputs, and a third one high inputs. The difference between these groups shows the amount of yields that can be realistically achieved by the farmers practising better farm management. The column with the yield potential finally shows figures under optimal soil conditions, water supply, crop husbandry and pest control, which is the ultimate goal of any farmer. It seems that in LM 3 & 4 these 30 farmers were others than the questioned ones for Tables 13 & 14 (survey areas 28-32, Tables 15 c-g). In Tables 13 a-e there is no fertilizer used, in Tables 15 c-g quite impressive amounts of it. The reason might be that Agricultural Officers wanted to show what they think is possible, and the round figures and very high yields in the groups with production level II and III are not from questionnaires, but hopeful guesses. This must be considered in reading the tables. The yields in LM 1 and 2 are also extraordinary high, 2400 - 6070 kg/ha in the first rainy season, 2500 - 4900 kg/ha in the second rainy season (Tables 15 a&b). But in the guidelines of Siaya District 1800 kg/ha resp. 900 kg/ha are reported as averages. That is another sample that in such surveys the better farmers are selected and high figures are given to make a good impression.

More detailed information can be found together with calculations of profitability in the Farm Management Guidelines of each district. The tables there are not yet connected with the suited Agro-Ecological Units which is necessary for the expected yields and the amount of inputs. The amount of fertiliser per soil unit is advised in MURIUKI & QURESHI: Fertiliser Use Manual, KARI 2001, more detailed in Chapter 3.4.6 here. An additional important reference material is the “Small Holder Farming Handbook for Self-employment”, first published in 1997 by Information Research and Communication Centre (IRACC) & Marketing Support Services Ltd, Nairobi. SIAYA GROUP 26

SIAYA DISTRICT

Subzone LM 1 l^m i of the Lower Midland Sugarcane Zone

This is theLower Midland Sugar Cane Zone with a long cropping season (= growing period of the rainy season) followed by a medium one and intermediate rains as typified by Sigomere Sub-location in Siaya District. The predominant soil type in this subzone is chromic and orthic ACRISOLS and rhodic FERRALSOLS, partly petroferric phases, and dystric phases, with dystric NITISOLS. The rainfall amount is variable but high and hence reliability is not really a factor of concern. The first rainy season can expect an amount of more than 750 – 950 mm (SW-NE) in 10 out of 15 seasons; the second rainy season > 600 – 800 mm. The 60% reliability of the growing periods during the 1st and 2nd rainy seasons is more than 190 and 130 - 150 days, respectively. The counting depends if the middle rains in August are connected with the first or second rainy season.

Although this is a sugarcane zone, there was no mention of it among the crops reportedly grown by farmers because transport to the factory is too expensive and not well organized. During the first rainy season, the following crops in order of importance are grown: maize and bean intercrop, sorghum, cassava, groundnuts, cowpeas and sweet potatoes. The dominant crops during the second rainy season are: maize and beans intercrop, sweet potatoes and cowpeas. There was no mention of permanent crops grown by the farmers in this Subzone (see Table 14f). But in fact there are at least a few cooking bananas and pawpaws. Passion fruit, mangoes and avocadoes should be planted because all are important for nutrition, esp. of children.

The constraints imposed by poor quality and degrading soil and water resources are consistently identified as the most widespread and pervasive constraints on agriculture in Siaya District together with striga infections. The lack of investment in replenishing natural resources forebodes dire long- term consequences for agriculture in many districts of Kenya. Changing this will need more than just soil and water technologies. It will require what has been termed the four ‘I’s, i.e. incentives, inputs, information and institutions, and these are not sufficiently evident in Kenyan smallholder systems. The improvement of soil fertility in this Subzone is very necessary, given that soil nutrients have been severely depleted through continuous cropping of agricultural land without replenishing the soil nutrients. Thus, any attempts to replenish soil nutrients could result in improved crop yields, particularly for the staple maize crop. This is clearly demonstrated in Table 15a. SIAYA GROUP 27

TABLETABLE 15a: 15a: INCREASE INCREASE OF YIELDS OF YIELDS BY BETTER BY BETTER FARM MANAGEMENT FARM MANAGEMENT IN AGRO- IN AGRO- ECOLOGICALECOLOGICAL UNIT1) LMUNIT 1,1) l^m LM 1,i, l^mUI D i, Ul1 D 1

Subzone: l^m i, Soil Unit: UI D 1 Survey area 33 (Sigomere) Crop Yields3) AEZ: LM 1 LOWER MIDLAND SUGAR CANE ZONE and Inputs Sub-zone: l^m i (Periods in days2): 1st rainy season 190 or more, 2nd rainy season 130 - 150 days) Unit with predom. Soil: Ul D 1 = chromic and orthic ACRISOLS and rhodic FERRALSOLS, partly petroferric phases, and dystric phases, with dystric NITISOLS Reliable rainfall: 1st rainy season >750 – 950 mm 2nd rainy season: >600 – 800 mm in at least 10 out of 15 years in at least 10 out of 15 years Farmers in Prod. Level Farmers in Prod. Level Maize local I= II= III= AEU I= II= III= AEU monocropped low med.4) high5) Pot.6) low med.4) high5) Pot.6) Yields3)kg/ha ------No Fertiliser7): monocropping N kg/ha ------of maize P2O5 kg/ha ------reported in this K2O kg/ha ------Subzone Manure t/ha ------Hybrid maize Yields3)kg/ha ------No Fertiliser7): monocropping N kg/ha ------of maize P2O5 kg/ha ------reported in this K2O kg/ha ------Subzone Manure t/ha - - - - -

Maize local Intercropped with beans Yields3)kg/ha 3432 4846 - * 3200 4900 - * Fertiliser7): N kg/ha 10.0 10.0 - 10.0 10.0 -

P2O5 kg/ha - 10.0 - - 10.4 - K2O kg/ha ------Manure t/ha 3.0 4.0 - 3.0 4.0 - Maize hybrid Intercropped with beans Yields3)kg/ha - 5082 6070 7000 Fertiliser7): N kg/ha - 20.0 30.0

P2O5 kg/ha - 20.0 30.0 K2O kg/ha - - - Manure t/ha - 5.0 6.0 Notes 1)Source: Interview of 30 farmers (if possible 10 in each level) 2004 by Divisional and Field staff 2) NotesFigures of these cereals growing periods should be reached or surpassed in 6 out of 10 years; growing periods may be considered longer due to 1) immediately following second rainy season by middle rains. Then the second growing period is shorter than the given figures Source:3) Interview of 30 farmers (if possible 10 in each level) 2004 by Divisional and Field staff 2) Achieved average yields with average rainfall Figures4)Farmers of with these medium cereals inputs growing periods should be reached or surpassed in 6 out of 10 years; growing periods may be5) consideredFarmers with longerhigh inputs due of to Fertiliser, immediately insecticides, following soil and second water conservation rainy season by middle rains. Then the second growing period6)Potential is shorter yield according than the to givencrop list figures and local climate of this Agro-Ecological Unit if soils are optimally fertilized, plus optimal crop management 3)Achieved7)Fertiliser averageapplications yields are averagedwith average at 20 % rainfall of pure nutrient 4)Farmers*Potential with for local medium maize notinputs known; no experimental results 5)Farmers with high inputs of Fertiliser, insecticides, soil and water conservation 6)Potential yield according to crop list and local climate of this Agro-Ecological Unit if soils are optimally fertilized, plus optimal crop management 7)Fertiliser applications are averaged at 20 % of pure nutrient *Potential for local maize not known; no experimental results SIAYA GROUP 28

Subzone LM 2 l^(m/s) i of the Marginal Sugarcane Zone

This is theLower Midland Marginal Sugar Cane Zone with a long cropping season followed by a (weak) medium to short one and intermediate rains as typified by Umala Sub-location in Siaya District. The predominant soil type in this subzone is orthic ACRISOL, with orthic FERRALSOLS, stony and partly petroferric phases, with Rock Outcrops. The rainfall amount is variable and hence reliability is a factor of concern. The first rainy season can expect an amount of >700 – 800 mm in 10 out of 15 seasons; the second rainy season > 500 – 680 mm. The 60% reliability of the growing periods during the 1st and 2nd seasons is more than 180 and 110 - 120 days, respectively.

In this Subzone, the current crops grown in order of ranking include: maize and beans intercrop, sorghum, cassava, sweet potatoes and sole maize. A similar crop mix is again cultivated during the second rainy season although it gets less rain but still enough and moisture is in the soil from the first one. The permanent crops grown include: cooking bananas, avocados, mangoes, pawpaws and passion fruits (see Table 14g). Sugarcane is not grown because of transport problems to the factory.

Efforts to improve soil fertility in this Subzone are very necessary, given that soil nutrients have been severely depleted. The continuous cropping of agricultural land without replenishing the soil nutrients is the main cause of this depletion. Thus, any attempts to replenish soil nutrients could result in improved crop yields, particularly for the staple maize crop. This is clearly demonstrated in Table 15g. SIAYA GROUP 29

TABLETABLE 15b: 15b: INCREASE INCREASE OF YIELDS OF YIELDS BY BETTER BY BETTER FARM MANAGEMENT FARM MANAGEMENT IN AGRO- IN AGRO- ECOLOGICALECOLOGICAL UNIT1) LMUNIT 2,1) l^(m/s) LM 2, l^(m/s) i, UI iG, Ul 2 G 2

Subzone: l^(m/s) i, Soil Unit: UI G 2 Survey Area 34 (Umala) Crop Yields3) AEZ: LM 2 MARGINAL SUGAR CANE ZONE and Inputs Sub-zone: l^(m/s) i (Periods in days2): 1st rainy season 180 or more, 2nd rainy season 110 - 120 days) Unit with predom. Soil: Ul G 2 = orthic ACRISOLS, with orthic FERRALSOLS, stony and partly petroferric phases, with Rock Outcrops Reliable rainfall: 1st rainy season >700 – 800 mm 2nd rainy season: >500 – 680 mm in at least 10 out of 15 years in at least 10 out of 15 years Farmers in Prod. Level Farmers in Prod. Level Maize local I= II= III= AEU I= II= III= AEU monocropped low med.4) high5) Pot.6) low med.4) high5) Pot.6) Yields3)kg/ha 2400 4200 - - 2500 4000 - * Fertiliser7): N kg/ha 5.0 10.0 - 5.0 10.0 - P2O5 kg/ha - 10.0 - - 10.0 - K2O kg/ha ------Manure t/ha 2.5 5.0 - 3.0 4.0 - Hybrid maize Yields3)kg/ha ------No monocropping Fertiliser7): of hybrid maize N kg/ha ------reported in this P2O5 kg/ha ------Subzone K2O kg/ha ------Manure t/ha ------

Maize local Intercropped with beans Yields3)kg/ha 3200 4940 - * 3122 4777 - * Fertiliser7): N kg/ha 5.0 15.6 - 5.0 15.6 -

P2O5 kg/ha - 15.6 - - 15.6 - K2O kg/ha ------Manure t/ha 3.0 5.0 - 2.5 5.0 - Maize hybrid Intercropped with beans Yields3)kg/ha 3800 4700 - 5800 Fertiliser7): N kg/ha 5.0 14.6 -

P2O5 kg/ha 5.0 14.6 - K2O kg/ha - - - Manure t/ha 3.0 5.0 - NotesNotes 1) 1)Source: Interview of 30 farmers (if possible 10 in each level) 2004 by Divisional and Field staff Source:2) Interview of 30 farmers (if possible 10 in each level) 2004 by Divisional and Field staff 2)FiguresFigures of of thesethese cerealscereals growing growing periods periods should should be reached be reached or surpassed or surpassed in 6 out of 10in years;6 out growing of 10 years; periods growing may be considered periods may longer due to immediately following second rainy season by middle rains. Then the second growing period is shorter than the given figures be3) consideredAchieved average longer yields due with to averageimmediately rainfall following second rainy season by middle rains. Then the second growing period4) is shorter than the given figures 3) Farmers with medium inputs Achieved5)Farmers with average high inputsyields of with Fertiliser, average insecticides, rainfall soil and water conservation 4) Farmers6)Potential with yield medium according inputsto crop list and local climate of this Agro-Ecological Unit if soils are optimally fertilized, plus optimal crop management 5)Farmers7)Fertiliser with applications high inputs are averaged of Fertiliser, at 20 % ofinsecticides, pure nutrient soil and water conservation 6)Potential*Potential yieldfor local according maize not to known; crop nolist experimental and local climateresults of this Agro-Ecological Unit if soils are optimally fertilized, plus optimal crop management 7)Fertiliser applications are averaged at 20 % of pure nutrient *Potential for local maize not known; no experimental results SIAYA GROUP 30

BONDO DISTRICT

Subzone LM 3 m^(s/vs) of the Lower Midland Cotton Zone

This is theLower Midland Cotton Zone with a medium cropping season followed by a (weak) short to very short one as typified by Ajigo Sub-location in Bondo district. The predominant soil type in this subzone are orthic LUVISOLS and eutric CAMBISOLS, petroferric and lithic phases, partly stony phases, with LITHOSOLS and Rock Outcrops. The rainfall amount is variable and hence reliability is a problem. The first rainy season can expect an amount of more than 480 – 600 mm (increasing from SW to NE) in 10 out of 15 seasons; the second rainy season more than 340 mm. The 60% reliability of the growing periods during the 1st and 2nd seasons is 140 - 155 and 75 – 85 days, respectively.

Although this Subzone has an association with the growing of cotton, no farmer mentioned growing this crop. The reasons for this decline in growing of cotton in the Subzones suited for cotton have been given at the start of the Agricultural Statistics (Chapter 3.2.3, p.142) in this volume. The current crops grown in this Subzone during the first rainy season in order of rank are: maize and beans intercrop, sorghum, cassava, sole maize, groundnuts, sole beans and sweet potatoes. During the second rainy season, the crops grown are ranked as follows: maize and beans intercrop, sole maize, sole beans and sorghum. Mangoes seem to be the only permanent crop grown by farmers in this Subzone (see Table 14a). There are more chances by additional crops (see Legend of AEZ Map). The pumpkin butternut could replace the cotton. The seeds contain protein and fat, they can be stored for sale in towns, where they are roasted and readily consumed. The surplus fruits could be feeded to pigs. The physic nut Jatropha contains 30% oil which can be used as diesel or for lamps and the pressed cake as a manure. Sunflowers and Desmodium should be planted as trap crops for Striga in rotation with the cereals.

Efforts to improve soil fertility in this Subzone are very welcome, given the low productivity of the soil. Technical approaches to overcome low soil productivity include (i) mulching with crop residues, (ii) hand- spreading of household wastes, animal manure and compost, (iii) corralling of livestock on fields, (vi) intercropping. Hereby, the proportion of yield increase varies with agroecological setting (soil types and rainfall) and the rates and frequencies of applying these amendments. This is clearly demonstrated in Table 15c. SIAYA GROUP 31

TABLETABLE 15c: 15c: INCREASE INCREASE OF YIELDS OF YIELDS BY BETTER BY BETTER FARM MANAGEMENT FARM MANAGEMENT IN AGRO- IN AGRO- ECOLOGICALECOLOGICAL UNIT1) LMUNIT 3,1) m^(s/vs) LM 3, m^(s/vs), UI ,V Ul 5 V 5

Subzone: m^(s/vs), Soil Unit: UI V5 Survey area 28 (Ajigo) Crop Yields3) AEZ: LM 3 LOWER MIDLAND COTTON ZONE and Inputs Sub-zone: m^(s/vs) (Periods in days2): 1st rainy season 140 - 155, 2nd rainy season 75 - 85 days) Unit with predom. Soil: Ul V 5 = orthic LUVISOLS and eutric CAMBISOLS, petroferric and lithic phases, partly stony phases, with LITHOSOLS and Rock Outcrops Reliable rainfall: 1st rainy season >480 mm 2nd rainy season: >340 mm in in at least 10 out of 15 years at least 10 out of 15 years Farmers in Prod. Level Farmers in Prod. Level Maize local I= II= III= AEU I= II= III= AEU monocropped low med.4) high5) Pot.6) low med.4) high5) Pot.6) Yields3)kg/ha 2125 3800 - * 1980 3500 - * Fertiliser7): N kg/ha 10.0 20.0 - 10.0 20.0 - P2O5 kg/ha 10.0 20.0 - 10.0 20.0 - K2O kg/ha ------Manure t/ha 3.5 4.0 - 3.0 3.5 -

Hybrid maize Yields3)kg/ha 3340 4800 6300 7000 Fertiliser7): N kg/ha 15.0 20.0 30.0

P2O5 kg/ha 15.0 20.0 30.0 K2O kg/ha - - - Manure t/ha 4.0 5.0 7.0 Maize local Intercropped with beans Yields3)kg/ha 2400 3500 - * 1800 3200 - - Fertiliser7): N kg/ha 10.0 15.0 - 10.0 20.0 -

P2O5 kg/ha 10.0 15.0 - 10.0 20.0 - K2O kg/ha ------Manure t/ha 4.0 4.0 - 3.0 3.5 -

Maize hybrid Intercropped with beans Yields3)kg/ha 3475 4500 6000 6500 Fertiliser7): N kg/ha 15.0 20.0 30.0

P2O5 kg/ha 15.0 20.0 30.0 K2O kg/ha - - - Manure t/ha 4.0 5.0 6.0 Notes 1)Source: Interview of 30 farmers (if possible 10 in each level) 2004 by Divisional and Field staff 2) NotesFigures of these cereals growing periods should be reached or surpassed in 6 out of 10 years; growing periods may be considered longer due to 1) immediately following second rainy season by middle rains. Then the second growing period is shorter than the given figures Source:3) Interview of 30 farmers (if possible 10 in each level) 2004 by Divisional and Field staff 2) Achieved average yields with average rainfall Figures4) of these cereals growing periods should be reached or surpassed in 6 out of 10 years; growing periods may Farmers with medium inputs be5) consideredFarmers with longerhigh inputs due of to fertiliser, immediately insecticides, following soil and second water conservation rainy season by middle rains. Then the second growing period6) is shorter than the given figures 3) Potential yield according to crop list and local climate of this Agro-Ecological Unit if soils are optimally fertilized, plus optimal crop management Achieved7)Fertiliser averageapplications yields are averagedwith average at 20 % rainfall of pure nutrient 4) Farmers*Potential with for local medium maize notinputs known; no experimental results 5)Farmers with high inputs of Fertiliser, insecticides, soil and water conservation 6)Potential yield according to crop list and local climate of this Agro-Ecological Unit if soils are optimally fertilized, plus optimal crop management 7)Fertiliser applications are averaged at 20 % of pure nutrient *Potential for local maize not known; no experimental results SIAYA GROUP 32

Subzone LM 3 m + (vs/s) of the Lower Midland Cotton Zone

This is the Lower Midland Cotton Zone with a medium cropping season and a (weak) very short to short one as typified by Nyawita Sub-location in Bondo District. The predominant soil type in this subzone is a complex of chromic and orthic ACRISOLS and dystric CAMBISOLS, petroferric or lithic phases and partly stony phases, and LITHOSOLS, partly stony phase. The rainfall amount is variable and hence reliability is a problem. The first rainy season can expect an amount of more than 420 – 540 (SW-NE) mm in 10 out of 15 seasons; the second rainy season > 200 – 330 mm. The 60% reliability of the growing periods during the 1st and 2nd seasons is 135 - 145 and 60 – 75 days, respectively.

One would expect that being a lower midland cotton Subzone, some farmers would report growing cotton. However, no farmer mentioned growing it during the survey. The reasons for the decline in cotton growing in these Subzones suited for cotton have been reported elsewhere in this volume (p.142). The current crops grown in the Subzone during the first rainy season in order of rank include: maize and beans intercrop, sorghum, sole maize and groundnuts. During the second rainy season, the crops grown are ranked as follows: maize and beans intercrop, sole maize. Mangoes appear to be the only permanent crop grown by farmers in this Subzone (see Table 14b). This is a poor situation which can be similarily improved as in the neighbouring Subzone (see text to Tables 14a & 15c).

Food insecurity in this Subzone is, apart from land shortage, mainly explained in terms of low and declining crop yields. There is strong evidence that yields can be raised through applications of external nutrient inputs, but specifically the N and P inputs added individually or in combinations (see Table 15d). Towards the adoption process, soil fertility replenishment options as f. i. mulching with Tithonia or manuring with Jatropha cake, should be evaluated side-by-side (or simultaneously) at on-farm level so that the end users and all stakeholders may have an opportunity to give their own assessment and rating of technologies in relation to effectiveness and economic-based information. Extension messages need updating frequently to educate the farmer, particularly on the newly introduced technologies. To this end, short and simple messages in form of brochures are important, as well as other dissemination media. SIAYA GROUP 33

TABLETABLE 15d: 15d: INCREASE INCREASE OF YIELDS OF YIELDS BY BETTER BY BETTER FARM MANAGEMENT FARM MANAGEMENT IN AGRO- IN AGRO- ECOLOGICALECOLOGICAL UNIT1) LMUNIT 3 1)m LM + (vs/s)3, m + (vs/s), Ul IC, Ul IC Subzone: (m/l + (vs/s), Soil Unit: Ul IC Survey area 29 (Bondo-West) Crop Yields3) AEZ: LM 3 LOWER MIDLAND COTTON ZONE and Inputs Sub-zone: m + (vs/s) (Periods in days2): 1st rainy season 135 - 145, 2nd rainy season 60 - 75 days) Unit with predom. Soil: UI 1 C = complex of chromic and orthic ACRISOLS and dystric CAMBISOLS, petroferric or lithic phases and partly stony phases, and LITHOSOLS, partly stony phase Reliable rainfall: 1st rainy season >420 – 540 mm 2nd rainy season: >200 – 330 mm in at least 10 out of 15 years in at least 10 out of 15 years Farmers in Prod. Level Farmers in Prod. Level Maize local I= II= III= AEU I= II= III= AEU monocropped low med.4) high5) Pot.6) low med.4) high5) Pot.6) Yields3)kg/ha 1742 3444 - * 1836 3500 - * Fertiliser7): N kg/ha 10.0 15.0 - 10.0 15.0 - P2O5 kg/ha 10.0 15.0 - 10.0 15.0 - K2O kg/ha ------Manure t/ha 2.3 3.4 - 2.5 4.0 -

Hybrid maize Yields3)kg/ha 3523 4900 5800 6800 Fertiliser7): N kg/ha 15.0 20.0 30.0

P2O5 kg/ha 15.0 20.0 30.0 K2O kg/ha - - - Manure t/ha 3.0 4.5 6.0 Maize local Intercropped with beans Yields3)kg/ha 1504 3000 - * 1600 3000 - * Fertiliser7): N kg/ha 10.0 15.0 - 10.0 15.0 -

P2O5 kg/ha 10.0 15.0 - 10.0 15.0 - K2O kg/ha ------Manure t/ha 2.0 3.0 - 2.0 3.0 -

Maize hybrid Intercropped with beans Yields3)kg/ha 3058 4700 5600 6000 Fertiliser7): N kg/ha 15.0 20.0 30.0

P2O5 kg/ha 15.0 20.0 30.0 K2O kg/ha - - - Manure t/ha 3.0 4.0 5.0 Notes 1)Source: Interview of 30 farmers (if possible 10 in each level) 2004 by Divisional and Field staff 2)Figures of these cereals growing periods should be reached or surpassed in 6 out of 10 years; growing periods may be considered longer due to immediately following second rainy season by middle rains. Then the second growing period is shorter than the given figures Notes3) 1) Achieved average yields with average rainfall Source:4) Interview of 30 farmers (if possible 10 in each level) 2004 by Divisional and Field staff 2) Farmers with medium inputs Figures5)Farmers of with these high cereals inputs ofgrowing Fertiliser, periods insecticides, should soil beand reached water conservation or surpassed in 6 out of 10 years; growing periods may be6) consideredPotential yield longer according due to to crop immediately list and local followingclimate of this second Agro-Ecological rainy season Unit by if soilsmiddle are optimallyrains. Then fertilized, the plussecond optimal growing crop management period7)Fertiliser is shorter applications than arethe averaged given figures at 20 % of pure nutrient 3) Achieved*Potential foraverage local maizeyields not with known; average no experimental rainfall results 4)Farmers with medium inputs 5)Farmers with high inputs of Fertiliser, insecticides, soil and water conservation 6)Potential yield according to crop list and local climate of this Agro-Ecological Unit if soils are optimally fertilized, plus optimal crop management 7)Fertiliser applications are averaged at 20 % of pure nutrient *Potential for local maize not known; no experimental results SIAYA GROUP 34

Subzone LM 3 m + (vs) of the Lower Midland Cotton Zone

This is theLower Midland Cotton Zone with a medium cropping season and a (weak) very short to short or very short one as typified by Nyavita-Maranda Sub-location in Bondo District. The predominant soil type in this subzone are eutric GLEYSOLS and pellic VERTISOLS, partly saline-sodic phases. The rainfall amount is variable and hence reliability is a problem. The first rainy season can expect an amount above 420 – 540 mm (SW-NE) in 10 out of 15 seasons; the second rainy season > 200 – 330 mm. The 60% reliability of the growing periods during the 1st and 2nd seasons is 135 - 145 and 45 – 75 days, respectively.

Like in other Subzones suited for cotton growing, no farmer mentioned it. An explanation for this has been given in South Nyanza in this volume (p. 142). The current crops grown during the first rainy season in order of ranking are: maize and beans, sorghum, finger millet, indigenous vegetables, cassava and groundnuts. During the second rainy season, the following crops dominate: maize and beans intercrop and indigenous vegetables. The permanent crops grown are cooking bananas, pawpaws and mangoes (see Table 14c). Few farmers try a bit of sugarcane but in AEZ LM 3 the growth is poor, in this driest subzone even very poor. Jatropha is a better option as a cash crop and the butternut, too.

Any efforts to improve soil fertility in this Subzone are very welcome, given the low productivity of the soil. The continuous cropping of agricultural land without replenishing the soil nutrients has led to severe depletion of plant soil nutrients. Thus, any attempts to replenish soil fertility could result in improved crop yields, particularly for the staple maize crop. This is clearly demonstrated in Table 15e. SIAYA GROUP 35

TABLETABLE 15e: 15e: INCREASE INCREASE OF YIELDS OF YIELDS BY BETTER BY BETTER FARM MANAGEMENT FARM MANAGEMENT IN AGRO- IN AGRO- ECOLOGICALECOLOGICAL UNIT1) LMUNIT 3 1)m LM + (vs3, m) ,+ BX (vs) ,2 BX 2 Subzone: m+ (vs), Soil Unit: BX 2 Survey area 30 (Nyavita-Maranda) Crop Yields3) AEZ: LM 3 LOWER MIDLAND COTTON ZONE and Inputs Sub-zone: m + (vs) (Periods in days2): 1st rainy season 135 - 155, 2nd rainy season 45 - 65 days) Unit with predom. Soil: BX 2 = eutric GLEYSOLS and pellic VERTISOLS, partly saline-sodic phases Reliable rainfall: 1st rainy season >420 – 540 mm 2nd rainy season: >200 – 330 mm in at least 10 out of 15 years in at least 10 out of 15 years Farmers in Prod. Level Farmers in Prod. Level Maize local I= II= III= AEU I= II= III= AEU Pot.6) monocropped low med.4) high5) Pot.6) low med.4) high5) Yields3)kg/ha ------No maize area Fertiliser7): under monocrop N kg/ha ------P2O5 kg/ha ------K2O kg/ha ------Manure t/ha ------

Hybrid maize Yields3)kg/ha ------No maize area Fertiliser7): under monocrop N kg/ha ------P2O5 kg/ha ------K2O kg/ha ------Manure t/ha ------

Maize local Intercropped with beans Yields3)kg/ha 2526 3394 - * 2455 3317 - * Fertiliser7): N kg/ha 10.0 15.0 - 10.0 15.0 -

P2O5 kg/ha 10.0 15.0 - 10.0 15.0 - K2O kg/ha ------Manure t/ha 2.0 4.0 - 2.3 4.0 -

Maize hybrid Intercropped with beans Yields3)kg/ha 3659 4350 5000 6000 Fertiliser7): N kg/ha 15.0 20.0 25.0

P2O5 kg/ha 15.0 20.0 25.0 K2O kg/ha - - - Manure t/ha 3.0 4.0 5.0 Notes 1)Source: Interview of 30 farmers (if possible 10 in each level) 2004 by Divisional and Field staff 2)Figures of these cereals growing periods should be reached or surpassed in 6 out of 10 years; growing periods may be considered longer due to Notesimmediately following second rainy season by middle rains. Then the second growing period is shorter than the given figures 1)Source:3)Achieved Interview average yields of 30 with farmers average (if rainfall possible 10 in each level) 2004 by Divisional and Field staff 2)Figures4)Farmers of with these medium cereals inputs growing periods should be reached or surpassed in 6 out of 10 years; growing periods may be5) consideredFarmers with longerhigh inputs due of to Fertiliser, immediately insecticides, following soil and second water conservation rainy season by middle rains. Then the second growing 6)Potential yield according to crop list and local climate of this Agro-Ecological Unit if soils are optimally fertilized, plus optimal crop management period7) is shorter than the given figures 3)AchievedFertiliser averageapplications yields are averagedwith average at 20 % rainfall of pure nutrient 4)Farmers*Potential with for local medium maize notinputs known; no experimental results 5)Farmers with high inputs of Fertiliser, insecticides, soil and water conservation 6)Potential yield according to crop list and local climate of this Agro-Ecological Unit if soils are optimally fertilized, plus optimal crop management 7)Fertiliser applications are averaged at 20 % of pure nutrient *Potential for local maize not known; no experimental results SIAYA GROUP 36

Subzone LM 4 (m/s) + vu of the Marginal Cotton Zone with Soil Ul VC

This is theLower Midland Marginal Cotton Zone with a medium to short growing season and a (weak) very uncertain rainy season as typified by Usenge Sub-location in Bondo District. The predominant soil type in this subzone are chromic and orthic ACRISOLS and ferralic CAMBISOLS, petroferric and lithic phases, partly stony phases, with LITHOSOLS and Rock Outcrops. The rainfall amount is very variable and hence reliability is a critical problem. The first rainy season can expect an amount of >350 – 480 mm in 10 out of 15 seasons, the second less than 200 mm and the rain is very scattered. The 60% reliability of the growing periods during the 1st rainy season is 125 - 135 days and there is no second reliable growing period.

The current crops being grown in this Subzone include the following in order of importance: maize and beans intercrop, sorghum, sole maize, cassava, cowpeas and sweet potatoes (see Table 14d). Considering the rainfall and growing period, early mature variety of butternut would be an option for intensification: to rise pigs with the fruits and sell the seeds. There were no crops mentioned for the second rainy season. Given the unreliability of rainfall in this Subzone, farmers should be encouraged to grow more of drought tolerant crops and forage (see Tables X and XI). Jatropha could do, the rains are sufficient for its growing period and the dry part of the year good for the rest the plant needs. The press cake is enriching the soil.

Efforts to improve soil fertility in this Subzone are very necessary, given that soil nutrients have been severely depleted. The continuous cropping of agricultural land without replenishing the soil nutrients is the main cause of this depletion. Thus, any attempts to replenish soil nutrients would result in improved crop yields, particularly for the staple maize crop. This is clearly demonstrated in Table 15f. SIAYA GROUP 37

TABLETABLE 15f: 15f: INCREASE INCREASE OF YIELDS OF YIELDS BY BETTER BY BETTER FARM MANAGEMENT FARM MANAGEMENT IN AGRO- IN AGRO- ECOLOGICALECOLOGICAL UNIT1) LMUNIT 4 1)m/s LM +4, (vu),m/s + (vu)UI VC, Ul VC

Subzone: m/s + (vu), Soil Unit: UI VC Survey area 31 (Usenge) Crop Yields3) AEZ: LM 4 MARGINAL COTTON ZONE and Inputs Sub-zone: m/s +vu (Periods in days2): 1st rainy season 125 - 135, 2nd rainy season: no reliable growing period) Unit with predom. Soil: Ul VC = chromic and orthic ACRISOLS and ferralic CAMBISOLS, petroferric and lithic phases, partly stony phases, with LITHOSOLS and Rock Outcrops Reliable rainfall: 1st rainy season 350 – 480 mm 2nd rainy season: 50 – 250 mm in at least 10 out of 15 years in at least 10 out of 15 years Farmers in Prod. Level Farmers in Prod. Level Maize local I= II= III= AEU I= II= III= AEU monocropped low med.4) high5) Pot.6) low med.4) high5) Pot.6) Yields3)kg/ha 1790 3050 - * - - - No maize area and Fertiliser7): crop yield for 2nd N kg/ha 10.0 15.0 - - - - rainy season P2O5 kg/ha 10.0 15.0 - - - - K2O kg/ha ------Manure t/ha 3.0 4.0 - - - -

Hybrid maize Yields3)kg/ha 2624 3443 4500 5500 Fertiliser7): N kg/ha 5.0 10.0 20.0

P2O5 kg/ha 5.0 10.0 20.0 K2O kg/ha - - - Manure t/ha 2.0 3.0 5.0 Maize local No maize area and Intercropped crop yield for 2nd with rainy season beans Yields3)kg/ha 1716 3260 - * - Fertiliser7): N kg/ha 5.0 10.0 - - - - -

P2O5 kg/ha 5.0 10.0 - - - - K2O kg/ha ------Manure t/ha 2.0 3.0 - -

Maize hybrid Intercropped with beans Yields3)kg/ha 2500 3300 4000 5000 Fertiliser7): N kg/ha 5.0 10.0 20.0

P2O5 kg/ha 5.0 10.0 20.0 K2O kg/ha - - - Manure t/ha 2.0 3.0 5.0 Notes 1)Source: Interview of 30 farmers (if possible 10 in each level) 2004 by Divisional and Field staff Notes2)Figures of these cereals growing periods should be reached or surpassed in 6 out of 10 years; growing periods may be considered longer due to 1) Source:immediately Interview following of second30 farmers rainy season (if possible by middle 10 rains.in each Then level) the second 2004 growing by Divisional period is andshorter Field than staff the given figures 2)Figures3)Achieved of averagethese cereals yields withgrowing average periods rainfall should be reached or surpassed in 6 out of 10 years; growing periods may be4) consideredFarmers with longermedium due inputs to immediately following second rainy season by middle rains. Then the second growing period5)Farmers is shorter with high than inputs the of given Fertiliser, figures insecticides, soil and water conservation 3)Achieved6)Potential yieldaverage according yields to with crop averagelist and local rainfall climate of this Agro-Ecological Unit if soils are optimally fertilized, plus optimal crop management 4)Farmers7)Fertiliser with applications medium are inputs averaged at 20 % of pure nutrient 5)Farmers*Potential with for local high maize inputs not ofknown; Fertiliser, no experimental insecticides, results soil and water conservation 6)Potential yield according to crop list and local climate of this Agro-Ecological Unit if soils are optimally fertilized, plus optimal crop management 7)Fertiliser applications are averaged at 20 % of pure nutrient *Potential for local maize not known; no experimental results SIAYA GROUP 38

Subzone LM 4 m/s + (vu) of the Marginal Cotton Zone with Soil VXC

This is the Lower Midland Marginal Cotton Zone with a medium to short cropping season and a very uncertain one as typified by Nyamonge Sub-location in Bondo District. The predominant soil type in this subzone is a complex of CAMBISOLS, ACRISOLS and FERRALSOLS, partly lithic phases, with Rock Outcrops and GLEYSOLS, with VERTISOLS and HISTOSOLS. The rainfall amount is very variable and hence reliability is a critical problem. The first rainy season can expect an amount of 350 – 480 mm in 10 out of 15 seasons. The 60% reliability of the growing periods during the 1st and 2nd seasons is 125 - 135 days and no reliable growing period, respectively.

The current important crops grown during the first rainy season are: sole maize, maize and beans intercrop, sorghum, sweet potatoes and cassava. During the second rainy season, sole maize and maize and beans intercrop are dominant on small fields, the few best places in the valleys. An array of permanent crops are grown mainly with soil moisture in the valleys. These include: mangoes, cooking bananas, citrus, oranges and pawpaws. Given the rainfall unreliability in this Subzone, it would be advisable for farmers to concentrate on growing drought tolerant crops, i.e. sorghum and pulses. Leguminous crops like cowpeas and green grams would be suitable candidates for this Subzone. Besides being drought tolerant, these legumes improve the fertility of the soil through nitrogen fixation. Jojoba is a suitable cash crop as in the other subzone of LM 4, and its press cake improves the soil.

Efforts to improve soil fertility in this Subzone are very necessary, given that soil nutrients have been severely depleted. The continuous cropping of agricultural land without replenishing the soil nutrients is the main cause of this depletion. Thus, any attempts to replenish soil nutrients could result in improved crop yields, particularly for the staple maize crop. This is clearly demonstrated in Table 15g. SIAYA GROUP 39

TABLETABLE 15g: 15g: INCREASE INCREASE OF YIELDS OF YIELDS BY BETTER BY BETTER FARM MANAGEMENT FARM MANAGEMENT IN AGRO- IN AGRO- ECOLOGICALECOLOGICAL UNIT1) LMUNIT 4,1) m/s LM 4,+ m/s(vu) +, (vu) VXC, VXC

Subzone: m/s + (vu), Soil Unit: VXC Survey area 32 (Nyamonge) Crop Yields3) AEZ: LM 4 MARGINAL COTTON ZONE and Inputs Sub-zone: m/s + (vu) (Periods in days2): 1st rainy season 125 - 135, 2nd rainy season: very uncertain, no reliable growing period) Unit with predom. Soil: VXC = complex of CAMBISOLS, ACRISOLS and FERRALSOLS, partly lithic phases, with Rock Outcrops and GLEYSOLS, with VERTISOLS and HISTOSOLS Reliable rainfall: 1st rainy season 350 – 480 mm 2nd rainy season: 50 – 250 mm in at least 10 out of 15 years in at least 10 out of 15 years8) Farmers in Prod. Level Farmers in Prod. Level Maize local I= II= III= AEU I= II= III= AEU monocropped low med.4) high5) Pot.6) low med.4) high5) Pot.6) Yields3)kg/ha 1830 3800 - * 1500 3000 - * Fertiliser7): N kg/ha - 10.0 - - 10.0 - P2O5 kg/ha ------K2O kg/ha ------Manure t/ha 3.0 4.0 - 3.0 4.0 -

Hybrid maize Yields3)kg/ha 1860 4443 - 5500 Fertiliser7): N kg/ha - 10.0 - P2O5 kg/ha - 10.0 - K2O kg/ha - - - Manure t/ha 3.0 5.0 - Maize local Intercropped with beans Yields3)kg/ha 1941 3443 - * 1585 3000 - * Fertiliser7): N kg/ha - 10.0 - - 10.0 - P2O5 kg/ha ------

K2O kg/ha ------Manure t/ha 3.0 4.0 - 3.0 3.0 -

Maize hybrid Intercropped with beans Yields3)kg/ha 2412 4862 - 5000 Fertiliser7): N kg/ha 10.0 15.0 - P2O5 kg/ha - 15.0 -

K2O kg/ha - - - Manure t/ha 3.0 4.5 - Notes 1)Source: Interview of 30 farmers (if possible 10 in each level) 2004 by Divisional and Field staff 2)Figures of these cereals growing periods should be reached or surpassed in 6 out of 10 years; growing periods may be considered longer due to Notes 1) immediately following second rainy season by middle rains. Then the second growing period is shorter than the given figures Source:3)Achieved Interview average yields of 30 with farmers average (if rainfall possible 10 in each level) 2004 by Divisional and Field staff 2) Figures4)Farmers of with these medium cereals inputs growing periods should be reached or surpassed in 6 out of 10 years; growing periods may be5) consideredFarmers with longerhigh inputs due of to Fertiliser, immediately insecticides, following soil and second water conservation rainy season by middle rains. Then the second growing period6)Potential is shorter yield according than the to givencrop list figures and local climate of this Agro-Ecological Unit if soils are optimally fertilized, plus optimal crop management 3)Achieved7)Fertiliser averageapplications yields are averagedwith average at 20 % rainfall of pure nutrient 4)Farmers with medium inputs 5)Farmers with high inputs of Fertiliser, insecticides, soil and water conservation 6)Potential yield according to crop list and local climate of this Agro-Ecological Unit if soils are optimally fertilized, plus optimal crop management 7)Fertiliser applications are averaged at 20 % of pure nutrient 8) Crops are grown in the valleys with additional soil moisture *Potential for local maize not known; no experimental results SIAYA GROUP 40 SIAYA GROUP 41

3.4.6 FERTILISER AND MANURE RECOMMENDATIONS FOR IMPORTANT AGRO- ECOLOGICAL UNITS

The Fertiliser Use Recommendation Project of the GTZ (FURP) from 1986 till 1992 had 3 trial sites in the Siaya group: one at Ukwala in Agro-Ecological Zone LM 2 (on orthic Acrisols/orthic to rhodic Ferralsols, representing the northern part of the Siaya group, LM 1 and LM 2), one at Siaya-Obambo in Agro-Ecological Zone LM 3 (on chromic Luvisols/orthic Ferralsols/dystric Nitosols, representing the centre of the district in an east-west strip to western Vihiga and northern Kisumu District, LM 1 - LM 3), and one at Yala Swamp in Agro-Ecological Zone LM 3 (on humic Gleysols/dystric Histosols, representing the western parts of the Siaya group as well as the other swampy -reclaimed- areas around Lake Victoria, LM 3 and LM 4). For other units like in the southwestern and northwestern region bordering to Busia District or in the SE bordering to Kisumu District, MURIUKI & QURESHI (2001) showed which results from other districts could be representative (like Bukiri-Buburi, Busia District, for SW and NW of the Siaya group, LM 3 and LM 4, ferralo-chromic Acrisols; or Mumias, Butere-Mumias District for SE and E of the Siaya group, LM 1 and LM 2, plinthic and ferralo-chromic Acrisols/orthic Ferralsols) and elaborated curves for fertiliser response according to the FURP 1. Recommended rates of an Agro-Ecological Unit (AEU) increase towards the wetter subzones and decrease into the dry ones if the soil unit extends there (see small maps). Generally, we have tended to lower the rates due to the low financial base of the smallholder farmers. If a system could be put in place to give the starter fertiliser on credit, repayable with part of the money obtained from harvest, then higher rates would be used by the farmers. The optimum can be calculated from the yield functions in MURIUKI & QURESHI (2001). In the long run the optimal amount must be given to maintain the nutrient content. Some quantities for this can be seen in chapter 3.1 under the ‘General Remarks’ section. Recommendations for higher application rates are given in the Smallholder Farming Handbook of the IRACC and MSS, Nairobi 1997, but the economic investment and risk is too high for the local farmers. A rural small credit system for the inputs could help a lot. Where scientific sources for quantifying the rates are lacking, some conclusions can be drawn from the difference of inputs and yields between the low and high production levels of the Farm Survey 2004. An empty column in the recommendation tables denoted as “Other Nutrients Recommended” does not mean that there is nothing to be done but it is because of lack of trial data. Symptoms of deficiencies and methods of addressing these can be found in MURIUKI & QURESHI (2001), Table 1&2, p.22-23. Finally it must be emphasized once more that fertilising alone will increase the yields only for some few years. The micronutrients that are not included in the fertiliser become exhausted very fast. Manuring almost up to the full return of the extracted nutrients is a must in order to have a stable agrobiological system for continuous sustainable production2. This advice is especially important for the soils developed on basement rocks which due to their senility have a low nutrient content. But it is also valid for the young volcanic soils like Phaeozems near Lake Victoria in southern Rarieda, which still have a higher nutrient content. This, for instance, was shown by the example of the fertile Phaeozems on the control plots during the 5 years’ FURP cultivation at Otamba, former Kisii District, where nutrients decreased significantly3. However, the application of Farm Yard Manure (FYM) led to a stabilization, even to an increase of org. C as well as pH and other nutrients (like P and Mg) in the long run; this is also positive for nitrogen mineralization and the improvement of soil physical quality (e.g. water storage capacity and plant available soil water, infiltration, aeration) and of the biological parameters. In Siaya group of districts, heavy application of FYM, crop residues and/or green manure is recommended to improve organic matter and N contents of the soils, which are suited to control the spread of Striga weed; Striga infestation is one of the major reasons for the serious reduction of maize yields in Western Kenya (MURIUKI & QURESHI, 2001, p. 90). Over the last years technologies have been developed by KARI Centre Kisii to maintain soil fertility and improve crop yields. So it was found that maize yields can be imroved up to 200-350 % when using a combination of 10 t/ha organic fertilisers (compost, farm yard manure) with an amount of inorganic fertilisers of only 30 kg/ha N and 30 kg/ha P2O5; this application is also reducing weeds, particulary Striga by about 75 % (KARI Kisii, unpublished paper, March 2009). Due to high prices for inorganic fertilisers small-scale farmers are advised to apply only 50% of the recommended optimum rates within the Integrated Nutrient Management (INM) approach4. This results in an increase of about 30% for maize yields; as cover crops farmers should intercrop Vetiver and Makarikari grass (in high potential areas: Dolichos lablab and SIAYA GROUP 42 mucuna) to prevent soil erosion (combined with methods of conservation tillage as ripping and pitting). In Kisii group of districts farmers have adopted this technology widely. Good results at KARI Kisii were also obtained from the application of 200 kg Minjingu rock phosphate fertiliser composted for 2 weeks with 5-10 t/ha FYM at planting of maize and vegetables, resulting in an increase of 50-300% for maize yields (acc. to KARI Kisii, unpublished paper, March 2009). Nowadays it is reported that the application of the newly developed Mavuno fertiliser should enhance crop production by 16-40% due to its composition of 10:26:10 NPK enriched with Ca, Mg and other essential micronutrients (acc. to information of Athi River Mining Ltd./ARM, April 2009). By inoculating soyabean with indigenous and introduced (surviving) strains of Rhizobium japonicum soyabean yields in SW-Kenya can be improved by as much as about 50%; so farmers have taken up this technology, too (KARI Kisii, unpublisher paper, March 2009).

______1 MURIUKI, A.W. & QURESHI, J.N. (2001): Fertiliser Use Manual.- Nairobi 2 Southern China has parts with similar soils to Nyanza Province and stabilized productivity there for hundreds of years by returning the kitchen waste as well as human and animal excrements to the fields. The organic material could be used together with the urea for biogas production first to reducethe hygienic and energy problems. 3 see Chapter 2.5, Table IX 4 Integrated Nutrient Management (INM) = combined use of organic and inorganic fertilisers in a sustainable way affordable to small-scale farmers SIAYA GROUP 43 SIAYA GROUP 44

TABLE 16a: FERTILISER AND MANURE RECOMMENDATIONS FOR THE AGRO-ECOLOGICAL UNITS of the two Sugar Cane Zones LM 1 l^m i and LM 2 l^(m/s) i, Soil Ul D1 & 2 1

Average Yield Average Yield Other Av. Exp. Yield + Recommended Crop varieties and Fertiliser Rates Increase if this Increase if 5t/ Nutrients Season Response-curve Rate is Applied ha Manure are Recom- kg/ha kg/ha ** kg/ha Applied mended 2 First rainy season Hybrid maize (H 622) 3 1645 - - 300 kg Maize & beans 4 1839 + 41.4 N – 30 N 890 (maize) * 0.39 N2

Sorghum (Seredo) 1415 + 49.9 P – 40 P2O5 1370 900 kg 0.39 P2 Second rainy season Hybrid maize (H 511) 3 1184 - - 300 kg Maize & beans 4 1093 + 28.2 N – 30 N 730 (maize) * 0.13 N2

Sorghum (Seredo) 665 + 31.6 P – 40 P2O5 770 900 kg 0.31 P2 Semi-permanent Sugar cane 5 ca. 8000-10000 300 CAN + 100 ca. 25000-30000 * Lime mixed double Super- with soil phosphate; 4t/ha at ratoons: 450 CAN planting, 250 + 150 double kg Muriate Superphosphate of Potash for 3rd ratoon Sources: muriuki, A.W. & qureshi, J.N.: Fertiliser Use Manual.- Nairobi 2001, p.90-92, and conclusions from the Farm Survey 2004; Information Research and Communication Centre (IRACC): Small Holder Farming Handbook for Self Employment.- Nairobi 1997, p. 167; KARI (Ed.): Fertilizer Use Recommendations. Vol. 12, Siaya District.- Fertiliser Use Recommendation Project (FURP), Nairobi 1987 1 Soil analysis showed that continuous cropping reduces available nutrients (P, K, Ca, Mg); organic matter content is very low. Heavy applications of FYM, crop residues and/or green manure are recommended to improve organic matter nutrients and N contents, which is suited also to control Striga weed (FURP, p. 6; MURIUKI/QURESHI, p. 90). 2 Potassium and lime applications had no effect on yields of annual crops, but periodic application of lime may be necessary (FURP). Regular soil tests should be performed to monitor soil pH, P, cations, N and organic C contents. 3 N fertiliser showed no response in monocropped maize due to Striga infestation and shallow soils (murram!) (FURP, p. 5). 4 Maize H 622 (1st r.s.), H 511 (2nd r.s.); beans GLP 2 (both seasons) in FURP-experiments. Today there are higher yielding varieties (see AEZs and Table X). 5 The Prov. Farm Managem. O.J. IMBIRA (Western Province) recommends (for practical reasons) lower amounts than IRACC: 4 bags/ha DAP or 9 bags/ha SSP and 2 bags/ha potash at planting time, 7 bags/ha CAN or 4 bags/ha urea as topdressing; 9 bags/ha CAN or 5 bags/ha urea for the ratoon. * data not available ** The actual conversion into the real nutrient content can be seen in Annex table I, p. 37. SIAYA GROUP 45 SIAYA GROUP 46

TABLE 16b&c: FERTILISER AND MANURE RECOMMENDATIONS FOR THE AGRO-ECOLOGICAL UNITS of the Mar- ginal Sugar Cane Zone LM 2 l^(m/s) i & l/m^(s/m) and the Cotton Zone LM 3 m/l^(s), Soils Um V1 & Ul V1 1

Average Yield Average Yield Other Av. Exp. Yield + Recommended Increase if this Crop varieties and Response-curve Fertiliser Rates 2 Increase if 5t/ Nutrients Season Rate is Applied ha Manure are Recom- kg/ha kg/ha ** kg/ha Applied mended 3 First rainy season Hybrid maize (H 622) 2208 + 40.8 N – 35 N 1050 * * 0.31 N2 Maize & beans 4 2155 + 17.8 N 15 N 270 (maize) * Sorghum (Seredo) 5 3593 - - 350 kg Cotton (to 2nd r.s.) ca. 300 100 CAN ca. 500 * (only in LM 3) Second rainy season Hybrid maize (H 511) 1784 + 26.9 N – 35 N 650 * 0.24 N2 + 9.6 P – 0.11 P2 Maize & beans 4 1597 + 9.7 N 15 N 150 (maize) * Sorghum (Seredo) 5 1966 - - 350 kg Semi-permanent Sugar cane 6 ca. 8000 300 CAN + 100 ca. 25000 * Lime mixed (only in LM 2) double Super- with soil phosphate; 4t/ha at ratoons: 450 CAN planting, 250 + 150 double kg Muriate Superphosphate of Potash for 3rd ratoon Sources: muriuki, A.W. & qureshi, J.N.: Fertiliser Use Manual.- Nairobi 2001, p.90-92, and conclusions from the Farm Survey 2004; Information Research and Communication Centre (IRACC): Small Holder Farming Handbook for Self Employment.- Nairobi 1997, p. 155 & 167; KARI (Ed.): Fertilizer Use Recommendations. Vol. 12, Siaya District.- Fertiliser Use Recommendation Project (FURP), Nairobi 1987 1 Soil analysis showed that continuous cropping reduces available nutrients (P, K, Ca, Mg) slightly; the organic carbon of the soils was low and decreased also with time. Therefore, heavy applications of FYM, crop residues and/or green manure are recommended to maintain/improve organic matter, N and P contents (FURP, p. 10). 2 Maize showed only a slight increase to P fertiliser because P content of the soils was in a sufficiency range (FURP, p. 9-10). 3 Regular soil tests should be performed to monitor soil pH, P, cations, N and organic C contents. 4 Maize H 622 (1st r.s.), H 511 (2nd r.s.); beans GLP 2 (both seasons) in FURP-experiments. Today there are higher yielding varieties (see AEZs and Table X). Beans showed no response to N and P fertiliser. 5 Sorghum responded weakly to N and P application (FURP, p. 9). 6 The Prov. Farm Managem. O.J. IMBIRA (Western Province) recommends (for practical reasons) lower amounts than IRACC: 4 bags/ha DAP or 9 bags/ha SSP and 2 bags/ha potash at planting time, 7 bags/ha CAN or 4 bags/ha urea as topdressing; 9 bags/ha CAN or 5 bags/ha urea for the ratoon. * data not available ** The actual conversion into the real nutrient content can be seen in Annex table I, p. 37. SIAYA GROUP 47 SIAYA GROUP 48

TABLE 16d: FERTILISER AND MANURE RECOMMENDATIONS FOR THE AGRO-ECOLOGICAL UNITS of the Swamp Area in the Cotton Zone LM 3 m+(vs/s) and in LM 4 (m/s)+(vu), Soil SA 2

Recommended Average Yield Average Yield Other Crop varieties and Av. Exp. Yield + Fertiliser Rates Increase if this Increase if 5t/ Nutrients Season Response-curve 1 Rate is Applied ha Manure are Recom- kg/ha kg/ha ** kg/ha Applied 2 mended 3 First rainy season Hybrid maize (H 622) 1 3457 + 11.7 + 6.9 P - - 70 kg Maize & beans 4 3128 + 13.0 N - - * Sorghum (Seredo) 1 4545 + 11.7 N - - * Cotton (to 2nd r.s.) ca. 300 100 CAN 500 * Second rainy season Hybrid maize (H 512) 1 3480 - - 170 kg Maize & beans 4 2558 - - * Sorghum (Seredo) 1 1941 - - *

Sources: muriuki, A.W. & qureshi, J.N.: Fertiliser Use Manual.- Nairobi 2001, p.90-92, and conclusions from the Farm Survey 2004; Information Research and Communication Centre (IRACC): Small Holder Farming Handbook for Self Employment.- Nairobi 1997, p. 155; KARI (Ed.): Fertilizer Use Recommendations. Vol. 12, Siaya District.- Fertiliser Use Recommendation Project (FURP), Nairobi 1987 1 Maize and sorghum responded weakly to moderately to N and P applications. At current prices of fertilisers and harvested products, application of N and P fertilisers is not economical. Soil analysis showed that continuous cropping reduces available nutrients (P, K, Ca, Mg) slightly; organic matter also decreased within the time of cropping (FURP, p. 13-14). As with continuous cropping particularly P becomes limiting, application of P might be economical. 2 Periodic applications of lime and organic manure are necessary to stimulate microbial activities. Regular application of organic fertilisers maintains/increases N and C contents of the soil (MURIUKI/QURESHI, p. 91). 3 No response of all crops to either potassium or lime application. Regular soil tests should be performed to monitor soil pH, P, cations, N and organic C contents. 4 Maize H 622 (1st r.s.), H 512 (2nd r.s.); beans GLP 2 (both seasons) in FURP-experiments. Today there are higher yielding varieties (see AEZs and Table X). The FURP plot was in LM 3. * data not available ** The actual conversion into the real nutrient content can be seen in Annex table I, p. 37. SIAYA GROUP 49 SIAYA GROUP 50

TABLE 16e: FERTILISER AND MANURE RECOMMENDATIONS FOR THE AGRO-ECOLOGICAL UNITS of the two Sugar Cane Zones LM 1 l^m i and LM 2 l^(m/s) i or l/m^(s/m), Soils Ul G2 & 3; Ul Y1 & X9 1

Average Yield Average Yield Other Crop varieties and Av. Exp. Yield + Recommended Increase if this Increase if 5t/ Nutrients Season Response-curve Fertiliser Rates Rate is Applied ha Manure are Recom- kg/ha kg/ha ** kg/ha Applied mended First rainy season

Hybrid maize (H 622) 1092 + 33.6 P – 25 N, 25 P2O5 734 390 kg K 0.4 P2 + 0.23 NP Local maize & beans 2 1291 + 0.37 P - - *

Beans (GLP 2) - - * 500 kg lime/ ha

Sorghum (Seredo) 662 + 40 P – 50 P2O5 1150 * “ 0.35 P2 Cotton (to 2nd r.s.) ca. 300 100 CAN ca. 500 *

Second rainy season

Hybrid maize (H 511) 398 + 26.9 P – 25 P2O5 498 290 kg 0.28 P2 Local maize & beans 2 545 + 8.5 P - - * Beans (GLP 2) - - * 500 kg lime/ ha Sorghum (Seredo) 3 571 - - * “

Sources: muriuki, A.W. & qureshi, J.N.: Fertiliser Use Manual.- Nairobi 2001, p.87, 97 & 98, and conclusions from the Farm Survey 2004; Information Research and Communication Centre (IRACC): Small Holder Farming Handbook for Self Employment.- Nairobi 1997, p. 155; KARI (Ed.): Fertilizer Use Recommendations. Vol. 2, Kakamega District.- Fertiliser Use Recommendation Project (FURP), Nairobi ca. 1995 1 Soil fertility is generally low (pH is very low, strongly acid), crop performance weak. Lime and compost with farm yard manure should be applied to improve basic soil fertility (FURP). 2 Yields of maize in the intercrop are here consistently higher than in the monocrop; fertilisation of intercrop is not economical, but P-fertilisation particularly in the second season can be promising (FURP). Today there are higher yielding varieties (see AEZs and Table X). 3 Sorghum can be considered as an alternative to maize (as mono- and intercrop with beans) due to higher yields and less P-requirements. * data not available ** The actual conversion into the real nutrient content can be seen in Annex table I, p. 37. SIAYA GROUP 51 SIAYA GROUP 52

TABLE 16f: FERTILISER AND MANURE RECOMMENDATIONS FOR THE AGRO-ECOLOGICAL UNITS of the Cotton Zones LM 3 m/l^(s) & m+(vs/s) and LM 4 (m/s)+vu, Soils Ul IC & Ul VC

Recommended Average Yield Average Yield Other Crop varieties and Av. Exp. Yield + Fertiliser Rates Increase if this Increase if 5t/ Nutrients Season Response-curve 1 Rate is Applied ha Manure are Recom- kg/ha kg/ha ** kg/ha Applied 2 mended 3 First rainy season

Hybrid maize (H 511) 1400 + 37.7 P – 25 P2O5 710 460 kg Lime + Mg 0.37 P2 + 0.13 NP + potassium

4 together Maize & beans 1705 + 19.5 P 75 P2O5 1460 (maize) * “

Sorghum (Seredo) 1519 + 65.6 P – 50 P2O5 1800 900 kg “ 0.59 P2 Second rainy season

Maize (KCB) (only in 1437 + 33.8 P – 25 P2O5 660 300 kg LM 3) 0.29 P2 + 0.14 NP 4 Maize & beans 892 + 23.7 P – 25 P2O5 480 (maize) * 0.18 P2 + 0.1 NP

Sorghum (Seredo) 695 + 26.6 P – 25 P2O5 520 * 0.23 P2 Biseasonal (or more) st nd Cotton (1 to 2 r.s.) 1411 + 23.1 P – 15 P2O5 300 * (BBA 75) 0.23 P2 Cassava (local) 5711 + 100 P – 30 P2O5 2180 * 0.91 P2

Sources: muriuki, A.W. & qureshi, J.N.: Fertiliser Use Manual.- Nairobi 2001, p. 92-94, and conclusions from the Farm Survey 2004; Information Research and Communication Centre (IRACC): Small Holder Farming Handbook for Self Employment.- Nairobi 1997, p. 155; KARI (Ed.): Fertilizer Use Recommendations. Vol. 9, Busia District.- Fertiliser Use Recommendation Project (FURP), Nairobi 1995 1 Soil analysis showed that continuous cropping reduces available nutrients (P, K, Ca, Mg); organic carbon content as well as pH of the soils also declined slightly with time (FURP, p. 7). 2 Regular application of organic fertilisers is necessary to maintain/increase N and C contents of the soil (MURIUKI/QUERESHI, p. 93). 3 Regular soil tests should be performed to monitor soil pH, P, cations, N and organic C contents. 4 Maize H 511 (1st r.s.), KCB (2nd r.s.); beans GLP 2 (both seasons) in FURP-experiments. Today there are higher yielding varieties (see AEZs and Table X). Yields of intercropped maize were lower in the 2nd r.s. than that of monocropped maize because of competition for limited soil moisture in the 2nd r.s. (FURP, p. 8). * data not available ** The actual conversion into the real nutrient content can be seen in Annex table I, p. 37. SIAYA GROUP 53 SIAYA GROUP 54

3.4.7 FINAL STATEMENTS

I. SUSTAINING AND IMPROVING THE SOIL FERTILITY

The global warming is not the main problem here. It will just reduce the coffee area but increase that for sugarcane. The real danger for the future is the exhausting of the soil. Most soils in Siaya group of districts are of low fertility. But the nutrients in the soil are the base for plant life and therefore for human life, too. Fertilizer alone cannot help enough because even the lacking of one of the many required nutrients is reducing the yield. Therefore, even although the yield increase by manure is not very convincing at the first glance, it is for the sustainability of the agricultural production necessary to keep the yield increase by fertilizer at the reached level for many years. Manure reduces also the damage caused by Striga weed. If there is no manure of animals available it must be delivered by humans. It can be applied hygienically by a kind of ecosan-toilets if about seven pails covered by a glass sheet are used. Urea should be put in an extra pail, mixed with two parts of water given directly to the crops (not touching the vegetables). Regarding the excrements in the pails, after some weeks in the sun most germs or amoebs are killed by the sunrays and heat. One pail (plus rubbish and ashes) per each second day should be carried to the fields, filled in holes or furrows, mixed there with soil for better transfer of the nutrients, and covered with earth to avoid runoff loss would be the easiest way. Better would be more pails and leave it longer, up to six months. Near the lake, farmers may use fish residues and compost of the water hyacinth Eichhornia as a complete manure. With some investment and if additional dung from livestock is available, basins for biogas are reasonable to be built (four cbm cost about 10 - 15 000 KSh 2009, the minimum size for a household). Schools may have big ones called biodigesters. This program was started by GTZ and is now carried on also by other donors. The remnants in the biogas installations are a valuable manure. Tithonia, the bush with yellow flowers, grows very well at the roadsides. Its branches give a very nutrious mulch when deployed on the fields. In AE Zones 4 & 5 of Bondo and Rarieda Districts there are calcareous horizons which can be dug out to supply lime to the zones 1 - 3 where it is needed.

II. ENABLING THE FARMERS TO CONTINUE

The productive work of the farmers is the base of all human life. They can only continue if they have at least the comparable minimum income of employees. Otherwise the whole system can collapse (see table 35 in South Nyanza Group). Most young people will not continue to produce food and cash crops. They run to town in hope for a better life but most of them cannot suceed. Therefore the government should encourage and subsidize farmers as Malawi does it successfully. The majority of farmers in the Siaya Group of Districts do not have enough land to produce the necessary income (compare the population and land tables with tables 17 and 18). Production must be intensified there, but the capital for the necessary investments cannot come out of the small production. Therefore the National Agricultural Accelerated Input Access Program with its subsidized package of seeds and fertilizers for poor families is a big help. On the other hand, family planning is definitely necessary to avoid further split up of the land which is too densely populated already. SIAYA GROUP 55

TABLE 17: BASIC NEEDS OF A RURAL FAMILY of 5 persons per year (prices 2009)

1.Basic Food Costs in KSh 1.5 bags of maize per head x5 = 7.5 x 90 kg = 675 kg Certified seeds 2 000 Fertilizer 3 500 Top dressing 2 400 Other costs 1 000 0.5 bags of beans per head x5 = 2.5 x 90 kg = 225 kg Seeds 1 500 Fertilizer 2 000 Salt, bread, margarine, jam 3 000 Tea 1 000 Milk, eggs, meat from own livestock, vet. cost 1 000 Sugar 7.5 kg per person x5 = 37.5 kg 3 200 Oil 1 800 Drinks (guests, funeral etc.) 5 000 2. Other necessities Soap and Omo 5 400 Clothes 2000 x 5 10 000 Shoes 500 x 5 2 500 Kerosin 5 l/month = 350 x 12 4 200 Wood fuel 2 000 Housing (building depreciation, repairs etc.) 4 000 Furniture 1 000 Radio, TV (incl. batteries), newspaper, books 12 000 Medical care 12 000 x 5 60 000 School requirements 1 000 x 3 3 000 School fees for 1 in secondary school 25 000 Unforseen expenses (transport etc.) 6 000 Social security 10 000 Total necessary money per year: 172 500 KSh +establishing new Sugarcane fields in AEZs LM 1 and 2 ca. 8 000 KSh

Sources: Inquieries by R. Jaetzold 2009 and information from Z. Mairura

TABLE 18: LAND REQUIREMENT FOR THE BASIC NEEDS of a rural family of 5 persons, sample in AEZ LM 3 Items Land (ha) Gross margin (KSh, 09) Maize and beans for food 0.2 (x2 seasons) Homestead and vegetables, cooking bananas, pawpaws 0.2 Grazing and forage for 1 cow & 1 oxen (for ploughing) 0.6 Grazing and forage for 4 milk goats 0.1 5.000 Maize for sale (pure stand, high management) 1.0 38 000 Beans for sale (pure stand, second season, same plot) --- 33 000 Tobacco, high management 0.4 68 000 Cotton 0.4 4 500 Sorghum (alternating seasonally with tobacco) --- 3 000 Cassava 0.3 21 000 Total: 3.2 ha (=8 acres) 172 500 KSh

Sources: District Farm Management Guidelines 2008 and 2009.