Are Smallholder Zambian Farmers Economists? A Dual analysis of farmers' expenditure in conservation...

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Are Smallholder Zambian FarmersEconomists? A Dual-Analysis of Farmers’Expenditure in Conservation andConventional Agriculture SystemsB. B. Umar a b , J. B. Aune a , F. H. Johnsen a & I. O. Lungu ca Department of International Environment and DevelopmentStudies, Norwegian University of Life Sciences, Aas, Norwayb Geography Department, University of Zambia, Lusaka, Zambiac Soil Sciences Department, University of Zambia, Lusaka, Zambia

Accepted author version posted online: 28 Mar 2012.Version ofrecord first published: 19 Oct 2012.

To cite this article: B. B. Umar, J. B. Aune, F. H. Johnsen & I. O. Lungu (2012): Are SmallholderZambian Farmers Economists? A Dual-Analysis of Farmers’ Expenditure in Conservation andConventional Agriculture Systems, Journal of Sustainable Agriculture, 36:8, 908-929

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Journal of Sustainable Agriculture, 36:908–929, 2012Copyright © Taylor & Francis Group, LLCISSN: 1044-0046 print/1540-7578 onlineDOI: 10.1080/10440046.2012.661700

Are Smallholder Zambian FarmersEconomists? A Dual-Analysis of Farmers’

Expenditure in Conservation and ConventionalAgriculture Systems

B. B. UMAR,1,2 J. B. AUNE,1 F. H. JOHNSEN,1 and I. O. LUNGU3

1Department of International Environment and Development Studies,Norwegian University of Life Sciences, Aas, Norway

2Geography Department, University of Zambia, Lusaka, Zambia3Soil Sciences Department, University of Zambia, Lusaka, Zambia

This article presents the results of a comparative study on conser-vation and conventional agriculture among smallholder farmersin Zambia. It shows that conservation agriculture in Zambia, ascurrently practiced, does not reduce labor required during criticalperiods of the farming cycle. We argue that smallholder farmerdecisions on whether or not to adopt conservation agriculturegoes beyond its agronomic and economic superiority over conven-tional practice. The farmers also consider its labor demands, cropsto be grown, and cultural norms. We show that farmers calcu-late their costs differently from conventional economic analysis.We conclude that promotion of conservation agriculture should beinformed by local and contextual factors.

KEYWORDS conservation agriculture, gross margins, farmingcycle, labor

INTRODUCTION

Conservation agriculture (CA) is an agricultural system based on the threeprinciples of minimum tillage, diversified crop rotations, and permanentsoil cover (Kassam et al. 2009). One concept frequently found in the

Address correspondence to B. B. Umar, Department of International Environment andDevelopment Studies, Norwegian University of Life Sciences. Box 5003, 1432. Aas, Norway.E-mail: [email protected]

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Are Small Zambian Farmers Economists? 909

literature and sometimes used interchangeably with CA is conservationtillage. However, CA is more than conservation tillage in that the latter isa collective term used to denote practices that retain at least 30% soil sur-face cover by residues. Conservation tillage uses some of the principlesof CA. Conservation tillage practices such as zero tillage can be transitionsteps toward CA (Hobbs 2007). CA was reportedly being practiced on about57 million ha (3%) of the 1,500 million ha of arable land worldwide in 2001(Food and Agriculture Organization of the United Nations [FAO] 2001). Thisfigure rose to 80 million ha or 5% by 2003 (Garcia-Torres et al. 2003) and isat present estimated to be 115 million ha (Derpsch et al. 2010). Most of theland under CA is in North and South America, and Australia (Derpsch et al.2010). Adoption and empirical evidence of the benefits of CA in Sub-SaharanAfrica (SSA) have been limited (Gowing and Palmer 2008; Rockstrom et al.2009). Benefits of CA reported include significant savings on fuel, labor, andmachinery costs, mainly because fewer passes over the field are requiredduring seedbed preparation (Lithourgidis et al. 2009; Derpsch et al. 2010).

Hobbs and Gupta (2004) found that CA significantly reduced produc-tion costs in the rice-wheat systems of the Indo-Gangetic Plains in South Asiaby about US$60 ha−1 mostly due to use of less fossil fuel and labor, and lesspumping of water. Since planting could be accomplished in one pass ofthe seed drill, planting time was also reduced, thus, freeing farmers to doother productive work (Hobbs 2007). Adoption of CA at the farm level wasassociated with lower labor and farm-power inputs (Wall 2007). Ekboir et al.(2002) and Lumkin and Sayre (2009) provided further examples of dramaticlabor reductions under CA. All of these examples reported labor reductionsin mechanized CA systems. Yet, a substantial number of smallholder farm-ers in SSA do not have access to mechanized tillage systems and, therefore,depend on manual and animal-based tillage systems such as use of tradi-tional hand hoe, planting sticks and moldboard ploughs. There is a dearthof knowledge on the economic benefits of CA in manual and animal-basedtillage systems of SSA. In this article, we report on a comparative study oflabor use in two CA systems and their equivalent conventional agriculturesystems. We find no evidence of labor saving resulting from adoption of CA.

The great diversity among smallholder farming environments has neces-sitated variations in agricultural systems and practices, and CA is not anexception. CA, as practiced in Zambia, involves two subsystems distin-guished by tillage implements: basin digging and ripping. According to theConservation Farming Unit (CFU), basin digging is supposed to be doneusing the wide-bladed Chaka hand hoe, which is heavier than the tradi-tional hand hoe in order to enable digging to large depths and the breakingof hoe/plough pans. Basins should be 30 cm long, 20 cm deep, and spaced70 cm apart along the rows which were 9 0cm apart (CFU 2009a). Thisresults in only about 30% of the soil being tilled. Ripping involves the use ofan ox-drawn ripper to make rip furrows that are 15–20 cm deep across the

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910 B. B. Umar et al.

prevailing slope at 90 cm spacing (CFU 2009b). This restricts tillage to onlyabout 10–12% of the land. We show in the results section that, in practice,these prescriptions are not followed to the letter. Crop residue retention,nitrogen-fixing crop rotations and cover cropping, dry-season land prepa-ration, and precise input application are other practices under this system.Conventional agriculture (CV) in the Zambian case is any farming methodthat involves complete soil inversion using a hand hoe or the moldboardplough. It is associated with the routine burning, grazing, or removal of cropresidues, and is often organized around the growing of maize. Food legumesand cucurbits are usually grown as intercrops. CA systems are also domi-nated by maize intercrops with legumes, although there is a drive towardintercropping with legumes that produce more biomass and make goodcover crops under the CA systems.

Proponents of CA usually highlight the increased yields and profitabilitythat result from its adoption. Higher economic returns under CA comparedto conventional practice have been reported. Yield gains of 50–300% afteradoption of CA have been reported (Twomlow et al. 2008; Mazvimavi andTwomlow 2009). The underlying assumption is that once the higher eco-nomic returns under CA are demonstrated to farmers, they will adopt or bemore likely to adopt the CA technologies. We argue that adoption of CA bysmallholder farmers depends on more than their knowledge and opportu-nity to adopt it. They take several factors into consideration, which are notalways aimed at profit maximization. These factors may hinder them fromadopting CA despite having the knowledge of its agronomic and economicsuperiority over CV. We also argue that the way households cost inputs isdifferent from the way economists do it as evidenced by the large variancein the costs calculated using partial budget analysis and as reported by thefarmers presented later in this article. This difference in computation mayactually lead them to find as profitable practices that are considered lossmaking by traditional economic analysis methods.

METHODS

The CFU, a unit under the auspices of the Zambia National Farmers’ Union,has been promoting CA under its Conservation Agriculture Programme(CAP) in the study areas. As part of this program, research has been con-ducted on various aspects of CA. The major part of the research involveda panel survey in which 640 questionnaires were administered to randomlysampled households annually over a four-year period, commencing from2007. Due to attrition, the sample size reduced to 535 in 2008, 486 in2009, and 435 in 2010. Other aspects of the research involved a study ofthe agronomic practices of the CA farmers (Umar et al. 2011); a study onthe perceptions of CA farmers toward climate change (Nyanga, Johnsen,

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Aune, and Kalinda 2011); the gender impacts and paradox of herbicideuse in CA among smallholder farmers (Nyanga Johnsen, and Kalinda2011), the potential for CA to respond to droughts and floods (Umar andNyanga 2011a), trends and possibilities for integrating CA with trees amongsmallholder Zambian farmers (Umar and Nyanga 2011b), potential of cassavain Smallholder CA systems (Nyanga and Umar 2011) and the challenges ofupscaling CA in Zambia (Nyanga 2011). The current study was carried outbetween July 2007 and September 2010. Data were collected through fieldassessments, semistructured household interviews, focus group discussions,and desk study.

Description of Study Areas

Three provinces were selected as study areas based on variations in agroe-cology and on past and current efforts in the promotion of CA (Figure 1).These were the southern, central, and eastern provinces.

The agroecology of the study areas varied in terms of annual rainfall,growing period, soil types, and elevation. The rainfall distribution isuni-modal and in a normal season ranges between 600 and 1000 mmannually with more rainfall toward the north of the country (Table 1).

FIGURE 1 Map of Zambia showing study areas (color figure available online).

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TABLE 1 Agroecological characteristics of the study areas

Study areas AER

Meanannualrainfall(mm)

Altitude(m.a.s.l.)

Growingseason(days) Soil types

Dominant farmingsystems

Monze 732 1080 Mixed crop andlivestock systems,animal poweredtillage dominates

Mumbwa II 804 1102 100−140 Lixisols, Luvisols,Alisols, Acrisols,Leptosols,Vertisols

Mixed crop andlivestock systems,animal poweredtillage dominates

Chipata 1033 1011 mixed crop andlivestock systems,hand hoe tillagedominates

Sinazongwe I 789 536 80−120 Nitosols, Luvisols,Vertisols,Arenosols,Leptosols,Solonetz

Mixed crop andlivestock systems,animal poweredtillage dominates

Adapted from Umar et al. 2011; Ministry of Agriculture and Co-operatives/Japanese International Co-operation Agency 2007.

The majority of the population of the study areas is engaged insmallholder farming and grows crops mainly for home consumption whilesome sell part of their produce. Major crops grown are maize (Zea mays),the country’s most important staple crop, cotton (Gossypium hirsutum), soyabeans (Glycine max), cowpeas (Vigna unguiculata), groundnuts (Arachishypogaea), sorghum (Sorghum bicolor), sweet potatoes (Ipomea batatas),cassava (Manihot esculenta), and various members of the cucurbit family.Smallholder farming systems are characterized by low productivity, use offamily labor, and low use of external inputs. Most of them include bothcrop and livestock production (Central Statistical Office [CSO] 2003). Thepopulation density ranges from 10 persons per km2 in southern and cen-tral provinces to 40 persons per km2 in Eastern Province. A typical farminghousehold would have in excess of 20 ha of land under its direct controlbut only about 10–20% of this land is cropped in any one season (Bwalya1999). Siegel and Alwang (2005) estimated the average cultivated farm sizeto be 5 ha. Similar to other areas where land is relatively abundant, sizeof cultivated land is not determined so much by limited access to land asby limited household access to labor for cultivation, with access to labor inturn constrained by the consumer to worker ratio (Dorward 1999), that is,the ratio of the total number of consumers in a household to the number ofhousehold members that are available for work in the household’s fields.

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Field Assessments

Use of labor on the different phases of the farming cycle was recordedby observation for both CV and CA systems. This was done by field assis-tants employed from within the study areas. The phases of the farmingcycle observed were land preparation, planting, weeding, and harvesting.Observations were made on how many persons were involved in a par-ticular farm operation and how long they worked per day. The farmingimplements used and the sources of labor used for the activity on thatday were recorded. The CA tillage systems monitored were basin diggingand ripping, while the CV tillage systems assessed were hand hoeing andploughing. The total area worked on at the end of each work day wasrecorded. In addition, the dimensions of the basins and rip lines were takenand recorded during land preparation. The workers were asked about thedrudgery associated with the activities as they performed them. The obser-vations were made on selected households on prior arrangement with them.The observations were made over a period of two complete farming seasons(2008–2009 and 2009–2010) in Monze, Sinazongwe, Mumbwa, and ChipataDistricts (Figure 1). The number of observations made for the four tillagesystems was 105 for basin digging, 41 for hand hoeing, 117 for ploughing,and 90 for ripping. At the end of each farming cycle (i.e., after harvest)the households were interviewed on their perceptions of labor used on thedifferent phases of the farming cycle, and on their input use and produce.

Questionnaire Surveys, Key Informant Interviews, and Focus GroupDiscussions

The households interviewed after field assessments were asked questionson their perceived labor use in terms of workload and number of workers,agronomic practices, farming expenditure, and crop yields. Key informantsincluded agriculture extension staff involved in CA and long-time resi-dents of the study areas. Two focus group discussions, consisting of eightmembers, each were held. The discussants were CA farmers among whichrepresented the practice of all the different tillage methods. One focus groupdiscussion was held in AER I while the other was in AER II. The discussioncentered on the labor demands of the CA and CV tillage systems, chal-lenges, and opportunities from CA at different phases of the farming cycle.Secondary data such as input and produce prices were obtained from reviewof statistical reports and other documents.

Statistical Analysis

Statistical analyses were carried out using MINITAB 15 for personal comput-ers (Minitab Inc. 2009) and PASW/SPSS 18 (SPPSS Inc. 2009). Analyses of

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variances (ANOVA) were conducted at a probability level of p ≤ 0.05 andthe means were compared using pair wise comparisons. To assess the costsand benefits associated with the two agricultural systems, the partial budgettechnique as described by CIMMYT (1988) was used. An economic analy-sis were performed using prevailing market prices for inputs at the time ofplanting and for outputs at the time the crop was harvested or the labor washired. The analysis was carried out based on maize enterprise. All costs andbenefits were calculated on a per hectare basis in Zambian Kwacha (ZMKha−1). Gross margins were calculated using the formula:

Gross Margins = Gross Income − Total Variable Costs.

Gross margins were then used to calculate the return to labor as below:

Returns to Labor = [Gross Margins (ZMK/ha) − Cost of Labor (ZMK/ha)

] /

Labor use in person-days/ha.

RESULTS AND DISCUSSION

Field assessments revealed basins were dug to average depths of 20 cm(SD = 2.5 cm), inter-row distance of 86 cm (SD = 10 cm), and inter-basindistance of 47 cm (SD = 20 cm). This resulted in more land being tilled thanrecommended. Only 52% of the households used Chaka hoes for diggingbasins while the rest used traditional hand-hoes. Ploughing was done usingthe ox-drawn moldboard plough. Hoeing was accomplished using the tra-ditional hand hoe, which is normally made up of a steel blade fitted to along wooden handle of about 1 m in length. Hand hoeing and ploughinginvolved the complete inversion of soils.

Labor Use in Hand-Based Conservation and ConventionalTillage Systems

Basin digging and hand hoeing were labor intensive tillage systems with24 and 21 person-days of work required per hectare (Table 1). Althoughbasin digging is a minimum tillage system, it is still labor intensive as itdemands tilling to depths of 20 cm and breaking of hoe or plough pans.It was sometimes performed during the dry season when soils were quitehard, which increased the drudgery of the operation. Ensuring correct basindepth, width and length; inter-row and inter-basin distances also takes uptime especially in the first year. Promoters of CA in Zambia encourage dryseason basin digging so as to reduce labor bottlenecks experienced duringcritical farming operations by relocating land preparation to the off-farming

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season (Haggblade and Tembo 2003; CFU 2009a; Haggblade and Plerhoples2010).

Switching from hand hoeing to basin digging would, therefore, notresult in labor saving. This is contrary to experiences reported under mech-anized CA (Lithourgidis et al. 2009; Hobbs 2007) and for manual CA systemsfrom Malawi (Ngwira et al. 2009), but similar to the Zimbabwean expe-rience (Mazvimavi and Twomlow 2009). Manual CA practiced in Malawiinvolves direct planting, which explains why labor expended under man-ual CA reduces compared to the CV tillage system which involves makingof ridges prior to planting. In Zimbabwe manual CA involves the diggingof basins that are 15 × 15 × 15cm in width, depth and length (FAO 2011).These are smaller than the basins promoted in Zambia but still required morework than CV manual practice (Mazvimavi and Twomlow 2009). The FAO(2011) reported that the basin-digging system required 69% more labor inZambia compared to the CV tillage system. The high labor demand in the CAsystem was attributed to the digging of the basins and the weeding practices.

Households that adopt CA are advised to have three adults work forabout three hours each morning. It was estimated that these three adultscould dig about 500 basins in three hours, and in this way complete onehectare in four weeks (CFU 2009a). This is equivalent to 47.6 person-daysof work per hectare. This is almost twice as much labor as compared to thefindings of this study. Siegel and Alwang (2005) reported 30 and 34 person-days per hectare for hand hoeing and basin digging, respectively. Basindigging labor requirements are claimed to diminish over time as soil structureimproves (Haggblade and Plerhople 2010).

Some CA proponents argue that the advantage of basins is not so muchthat they save labor but rather that they spread labor out of the peak periodat the beginning of the farming season resulting in a more favorable dis-tribution of farm labor. By commencing their land preparation immediatelyafter harvest, labor constrained households spread their labor over the dryseason and dig a few basins a day so that by the beginning of the rainyseason, which also marks the beginning of the farming season, these house-holds are finished with their land preparation and ready to plant their crops.We have reported on the challenges of dry season land preparation in arelated study. Most households prefer to engage themselves in non-farmingactivities during the dry season in their efforts to diversify their livelihoodstrategies (Umar et al. 2011).

The amount of labor used to plant one hectare with seed was similar forthe two hand-based tillage systems (p > 0.2). There were no statistically sig-nificant differences in the person-days per hectare spent on hand weedingamong the two hand-based tillage systems (Table 2). In some cases, oxenand herbicides were used to supplement hand weeding efforts. An averageof 18.2 and 12.8 person-days per hectare was obtained for hand weedingfields where herbicides had been applied and oxen used for weeding,

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TABLE 2 Labor use on different phases of farming cycle for hand-based tillage systems (fromfield assessments)

Labor use Labor source (%)

Tillage Farming operationsPerson-days

ha−1Number ofworkers

Householdonly

Hiredonly

Household,hired,

farmingcircle

Basindigging

Land preparation 24.0a (40.1) 2.4a (1.7) 86.6 7.1 6.3Planting 2.0a (1.0) 6.7a (5.0) 50.4 5.3 44.3Weeding 44.4a (34.3) 8.5a (8.1) 69.2 26.2 4.6subtotal 70.4a

Harvesting 54.1a (81.8) 8.3a (6.6) 36.7 11.1 52.2total labor used

(person-days ha−1)124.5a

Total no. of workersfor farming cycle

30.1a

Handhoeing

Land preparation 21.2a 3.4b (2.2) 58.6 20.7 20.7Planting 3.0a 4.1b (3.2) 80 10 10Weeding 48.4a (39.7) 7.7a (5.9) 83.3 16.7 0subtotal 72.6a

Harvesting 72.7a (96.1) 6.0b (5.3) 29.4 17.7 52.9total labor used



20.7b

Comparisons between the two hand-based systems are made for all the farming operations. Differentletters for a farming operation between the two systems means statistically significant difference at p ≤0.05. The figures in parentheses are standard deviations.

respectively. The labor spent on hand weeding fields where oxen had beendeployed was less than (p < 0.05) that spent on fields where hand weedingonly and herbicides were used as control measures. Using oxen for weed-ing, thus, significantly reduced the number of person-days required to weedregardless of tillage system. There is, therefore, an opportunity for increaseduse of oxen not just for land preparation but for weeding as well. Oxenwere mainly used for weeding ploughed and ripped plots.

Application of herbicides did not seem to reduce the weedinglabor requirements. This was plausibly due to their incorrect applica-tion. Smallholder Zambian farmers apply an average of 0.6 liters ha−1 ofherbicides instead of the recommended 4–5 liters ha−1. This is done inefforts to spray the limited quantities of the herbicides onto as much oftheir cultivated fields as possible. The most common herbicide appliedwas glyphosate (N -(phosphonomethyl) glycine, 41% active ingredient). Thisherbicide was diluted using water from sources that were also used by live-stock. This invariably made the water muddy and reduced the efficacy ofthe glyphosate as it deactivated on contact with soil particles in the muddywater. Farmers also found the herbicide application instructions difficult to

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follow and sometimes applied expired herbicides (Umar et al. 2011). Only1.7%, 6.4%, and 8.2% of the CA farmers reported using herbicides duringthe 2007–2008, 2008–2009, and 2009–2010 farming seasons, respectively.Reasons for not using herbicides were a lack of proper knowledge on whatkind of herbicides to use, how to make dilutions, when to apply them,and the right crops on which to apply them. Cases of wrong application ofherbicides were common (Nyanga, Johnsen, and Aune 2011). In this study,only 8% of the sampled households used herbicides.

The results from our panel survey showed that an average of 0.3 ha wasunder basins between the 2006–2007 and 2009–2010 seasons. The tillage sys-tem has not significantly reduced the labor demands in smallholder farmingsystems, which are characterized by severe labor shortages and drudgeryduring critical periods. This may explain why farmers prefer to only allocatesmall portions of their land to basin digging despite its superior crop yields.The urgent need for high labor inputs during land preparation and weed-ing coincides with the period when food is most scarce. This inhibits bothhumans and draught animals from working at full capacity and explainsfarmers’ preference for spending only a few hours per day on farmingactivities and a desire for labor saving technology.

Basin digging was characterized by more dependence on householdlabor as household members were found to be the only ones involved inthis operation in 87% of the instances when field monitoring was done,while hired labor only was noted in 7% of the instances and a combinationof household, hired and farming circle labor was observed in 6% of thecases. The percentages for hand hoeing were 59% for household labor only,21% for hired labor only, and about 21% for the combination. Farming circlesare made up of groups of people of similar interest (e.g., members of samevillage, church, community-based organization, etc.) that spend at least a dayworking on the fields of one of their members. In exchange, the householdreceiving the help provides the workers with a traditional drink or a meal.The help is reciprocated until all the members of the farming circle havebeen helped in the same way. Focus group discussions and key informantinterviews revealed that it was difficult to hire labor for basin digging as itwas perceived to be very hard work. More people were involved in plantingin basins. The percentage of households using all the three sources of laborfor planting was higher in the basin systems than the other three tillage whilethe bulk of the labor (87%) used for planting in ripped areas was suppliedby the households.

Labor Use in Animal Powered Conservation and ConventionalTillage Systems

Ripping one hectare of land required about 0.8 person-days while ploughingrequired 3.8 person-days per hectare (Table 2). The workload for rippingwas just 21% of that needed to plough one hectare. The reduced workload

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under ripping was because less than one third of the land is tilled underthis system while ploughing involves the complete inversion of the soilover the entire area. Ripping also requires less traction power as there isno soil inversion, therefore, the oxen can work faster. The Golden ValleyAgricultural Research Trust (2001) reported from its on-station research ontillage systems that ploughing needed two to three times more workdaysthan ripping. Ripping seemed to significantly reduce labor needs and couldbe an important tillage system for Zambian smallholder farmers that face crit-ical labor shortage during land preparation and also reduce costs associatedwith hiring of oxen as the oxen would be hired for shorter periods.

The number of person-days used to plant one hectare with seed wassimilar for the two animal powered tillage systems (p > 0.2). Hand weedingripped fields required more person-days of work per hectare than ploughedareas (Table 3). Ploughing tillage system employed a larger number ofworkers over the complete farming season, compared to the ripping sys-tem (p = 0.002). Similar numbers of workers were observed during landpreparation and hand weeding, but were higher for planting and harvestingunder ploughed system.

TABLE 3 Labor use in different phases of farming cycle for animal powered tillage systems(from field assessments)

Labor use Labor source

Tillage Farming operationsPerson-days

ha−1Number ofworkers

Householdonly

Hiredonly

Household,hired,

farmingcircle

Ripping Land preparation 0.8a 2.0a 66.4 33.6 0Planting 2.6a 4.8a (3.4) 86.7 0 13.3Weeding 52.9a (85.0) 10.5a (7.4) 46.2 7.7 46.2Subtotal 56.2a

Harvesting 27.0a (16.1) 10.9a (7.3) 34.5 4.4 61.1Total labor used



23.4a

Ploughing Land preparation 3.8b 2.0a 61.8 38.2 0Planting 2.0a 5.1b (3.5) 58.9 1.6 38.7Weeding 32.1b (30.9) 9.7a 70.6 3.7 25.7Subtotal 37.9b

Harvesting 22.8b (12.9) 10.8b (6.8) 41.2 7.9 50.9Total labor used



28.5b

Comparisons between the two animal powered systems are made for all the farming operations. Differentletters for a farming operation between the two systems means statistically significant difference at p ≤0.05. The figures in parentheses are standard deviations.

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Comparisons were made between workload and number of workersfor all the fields that were only hand-weeded and those where herbicidesand oxen were used for weeding in addition to the hand weeding. At 12.8,the number of person-days for hand weeding fields which had earlier beenweeded with oxen was significantly less than the rest (Table 4). About fourworkers (SD = 2) per hectare were used to hand weed plots on which oxenhad been employed, while an average of 13.9 workers (SD = 16.3) wereused to hand weed plots where herbicides had been applied per season.This was significantly less than the number of workers per hectare used onthe plots where neither herbicides nor oxen had been used (p < 0.0001).

Oxen and herbicides seemed to have been used on plots that wereconsidered very important by the households as the sources of the laborrevealed inclusion of household, hired and farming circle labor in 81% of theinstances when field observations were made. The large number of workersengaged in weeding seemed to be indicative of the pressure householdswere under to complete weeding before the crops were overwhelmed byweeds and the serious labor bottlenecks experienced by households withoutaccess to hired labor. The plots were hand weeded an average of 3.8 timesafter the application of herbicides and an average of 4 times for the plotswhere oxen were used per season. This was significantly higher than the1.9–2.2 times for plots that were only hand weeded. This seems to show thatnot enough weeding was done on the plots that were hand weeded onlyrather than that the other fields required more weeding. The number of timethe fields were weeded after application of herbicides also indicates the inef-ficacy of the usually expired and misapplied herbicides in this case. Correctusage of herbicide has been reported to significantly reduce hand weedinglabor requirements. There is an urgent need to train the smallholder farminghouseholds in correct usage of herbicides or find alternatives to their use.

TABLE 4 Comparison of labor use based on weeding measures

Basindigging

Handhoeing Ripping Ploughing Oxen Herbicides

Number ofperson-days/ha

20.2a 23.8a 22.0a 16.9a 12.8b 18.2a

Normal seasonweeding times

2.2a (0.6) 2.2a (0.7) 2.4a (0.6) 1.9a (0.3) 4.4b (0.8) 3.8c (1.4)

Total no. ofworkersweeding/ha

28.5a (22.4) 29.5a (17.1) 26.2a (39.2) 19.5a (17.1) 4.3b (2.0) 13.9c (16.3)

Sources of labor (%)Household only 69.2 83.3 46.2 70.6 19.2 34.6Hired only 26.2 16.7 7.7 3.7 0.0 0.0Household, hired,

farming circle4.6 0 46.2 25.7 80.8 65.4

N 68 10 55 112 54 28

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The harvesting phase seemed to be the most relaxed period of the farm-ing cycle. Household members and their relatives and friends were observedharvesting their crops in a relaxed manner without the sense of urgency thatcharacterized the other phases of the farming cycle. There were no seriouslabor bottlenecks during harvesting as the dry season, during which harvest-ing was done, lasted several months. Households could also afford to hirelabor and pay for it in kind with farm produce or cash with money raisedfrom its sale.

Trained oxen were owned by about 62% and 66% of the householdsthat employed ploughing and ripping tillage methods, respectively, whilethe rest hired oxen. More households owned rippers (75%) compared toplows (70%). Also, there were households that owned plows and rippersbut did not own oxen. This could have been due to loss of oxen throughlivestock diseases that have affected the national livestock population inthe past several years and the acquisition of rippers from CA promoters byhouseholds without oxen.

The animal-based systems demanded less labor for the entire farmingcycle compared to the manual systems. These differences arose from themuch lower labor used during the land preparation phase in the animal-based systems. Less time was spent on harvesting from the animal-basedsystems compared to the manual systems. This could have been influencedby what households intended to do with the crops grown in these systems.There is more urgency in harvesting maize that is to be sold to the centralgovernments’ maize buying parastatal, the Food Reserve Agency (FRA). FRAoffers pan-seasonal and pan-territorial above market price for maize grain(Burke et al. 2010) but has strict regulations of only buying maize withmoisture content at 12.5%. This motivated farmers to harvest, dry, and delivertheir maize as early as possible. This maize was, more often than not, fromtheir ploughed and ripped fields.

Comparison of Actual Labor Use and Households’ Perceptions

Perceptions of labor use were investigated by asking households how muchlabor they had spent on the different phases of the farming cycle. This wasdone at harvest time. This was done in order to assess whether or not thework perceived to be required for each tillage system somehow affected thehouseholds’ decisions. Overall, no significant differences were observed inthe labor use and total number of workers based on tillage system althoughthere were differences between particular operations of the farming cycle(Table 5).

The number of person-days of work reported as spent on land prepara-tion was higher under basins compared to hand-hoeing system (p < 0.0001),while no differences were reported between ripping and ploughing. Plantingreportedly required more person-days ha−1 under the hand-hoe system (p <

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TABLE 5 Farmer recall of labor use on farming activities

Basinsn = 90

Hand-hoen = 85

Rippedn = 111

Ploughedn = 114

No. of person-days/haLand preparation 34.0a (25.9) 13.4b (9.2) 7.8c (10.3) 8.8c (11.2)Planting 4.5ac (5.6) 12.0b (16.3) 2.8c (2.3) 5.5a (6.0)Weeding 47.0a (41.4) 48.8a (38.4) 43.0a (45.2) 38.7a (32.3)Subtotal 79.9 63.8 55.8 53Harvesting 8.9a (8.8) 6.8a (5.7) 7.0a (5.8) 10.4b (9.3)Total 88.8a 70.6a 62.8a 63.4a

No. of workersLand preparation 6.2a (3.8) 5.1a (3.5) 6.3a (5.2) 6.5a (3.0)Planting 5.6a (4.8) 5.0a (3.2) 5.8a (4.7) 6.1a (3.9)Weeding 17.9 (12.6) 14.6 (9.7) 21.2 (13.1) 19.4 (10.6)Subtotal 29.7 24.7 33.3 32Harvesting 7.4ab (5.1) 7.0a (3.6) 8.5bc (5.0) 9.1c (3.9)Total 37.1a 31.7a 41.8a 41.1a

aMeans followed by the same letter in row are not statistically different at p ≤ 0.05 probability level. Thevalues in parentheses are standard deviations.1 person day = 6 h.

0.0001) compared to the basins, while ripped fields also required less thanploughed fields. No differences were reported in the labor spent on weedingamong the four tillage systems. Labor reportedly spent on harvesting fromploughed system was significantly higher (p = 0.001) than the other threesystems. Ox-plough farmers would perceive any manual land preparationmethod to be more labor demanding. Traditional hand-hoe farmers usedto digging much shallower furrows using light traditional hand hoes wouldalso perceive basin digging, which is characterized by the use of the muchheavier Chaka hoe and digging to much deeper levels beyond the hoe andplough pan to be much more difficult work. The households’ perceptions ofthe drudgery associated with basin digging were unanimously expressed byfarmers, key informants and in focus group discussions.

A comparison of the farmer recall figures and the field monitoringresults revealed a general underestimation of labor expended on all the fourtillage systems and an overestimation of the number of workers involved inthe entire farming cycle (Table 6).

TABLE 6 Comparison of farmer recall responses and field monitoring information

Person-days/ha∗ Number of workers∗

Basins Hand hoe Ripped Ploughed Basins Hand hoe Ripped Ploughed

Farmer recall 88.8 70.6 62.8 63.4 37.1 31.7 41.8 41.1Field

monitoring124.5 145.3 83.2 60.7 30.1 20.7 28.5 23.4

∗For complete farming cycle.

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Underestimations of up to 28% and 51% of the actual labor spent onbasin and hand-hoe tillage systems, respectively, were noted while for rip-ping system the underestimation was 25% of the actual for the completefarming cycle. Labor spent on ploughing was overestimated by 4%. While themonitoring results showed that more labor was spent on the two hand-hoe-based systems, the farmers’ perceptions of work done during the differentphases of the farming cycle for all the four tillage systems showed them tobe equally demanding in terms of labor. Conversely, the number of work-ers was overestimated by 23%, 53, 47%, and 76% for the basin, hand hoe,ripped, and ploughed systems, respectively (Table 6).

Gross Margin and Marginal Analysis for CA and CV Systems

The average maize yields reported from the field assessments were 4.4 and1.7 tons ha−1 for basins and hand-hoe systems, respectively. Average maizeyields were 2.4 and 2.8 tons ha−1 from ploughed and ripped systems,respectively. The yields from basins were 159% higher than those fromthe hand-hoe system while the yields from the ripped areas were 17%higher than from the ploughed areas on a per hectare basis (Table 7).The FAO (2011) reported that during the 2008–2009 season CA maizeyields were 3 tons per hectare, which was 42% higher than the maizeyields from CV ploughed fields. Maize yields were found to be significantlyhigher under the CA systems compared to the CV systems (Umar et al.2011).

TABLE 7 Partial budget analysis for CA and CV systems of smallholder farmers

Basindigging

Handhoeing Ploughing Ripping

Average maize yield (tons/ha) 4.4 1.7 2.4 2.8Gross income (ZMK/ha) 3,960,000 1,530,000 2,160,000 2,520,000Cost of fertilizer (ZMK/ha) 390,280 330,000 894,960 954,360Cost of manure (ZMK/ha) 130,710 229,680 515,400 207,300Cost of herbicides/pesticides

(ZMK/ha)66556 91,500 116,348 75,429

Cost of labor (ZMK/ha) 954,000 600,000 600,000 350,000Cost of seed (ZMK/ha) 205,500 244,005 303,672 429 338Total variable costs (ZMK/ha) 1,747,046 1,495,185 2,430,380 2,016,427Gross margin (ZMK/ha) 2,212,954 34,815 −270,380 503,573Returns to labor

(ZMK/person-days)23,567 4,112 4 172 14 641

Price of maize was ZMK 900,000/ton. Manure = ZMK15,000/“50 kg” bag. The cost of labor was cal-culated based on going casual labor wage rates in the areas. Land preparation of basins ranged fromZMK50/basin in parts of Eastern Province to ZMK150,000/ha in parts of Central Province. Weeding laborranged from ZMK 150,000 to 300,000 per hectare. Herbicide price was ZMK60,000/l while pesticide pricewas ZMK 132,000/2 kg. A 50 kg bag of fertilizer cost ZMK 220,000. 1US$ = ZMK 4,755 (as of February 18,2011).

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The ploughing tillage system had the highest total variable costs (TVC)followed by the ripping system. The largest contribution to the TVC for thesetwo tillage systems was the fertilizer costs. The gross margin was highest forthe basin system and lowest for the ploughing system. The basin system wassuperior in terms of maize yields and yielded higher gross income than theother systems. The quantity of fertilizer applied onto the basins was only44% and 41% of that applied in the ploughed and ripped areas, respectively.Yield levels were nevertheless better from the basin system. This was proba-bly because the precise fertilizer application of nutrients in basins led to highnutrient use efficiency (FAO 2010; Marongwe et al. 2011). It was profitablefor a household to switch from CV to CA. The marginal rate of return (MRR)between hand hoeing and basin digging and hand hoeing and ripping was860% and 90%, respectively. The MRR between ploughing and ripping andploughing and basin digging was 187% and 360%, respectively. The returnsto labor under CA were 3.5–6 times higher than under CV systems. Based ongross margin analysis, households would maximize their benefit by switch-ing to basin digging. The persistence of CV tillage may show that householdsdo not only base their decisions on gross margins or that their net benefitsare different because they do not cost inputs at prevailing market rates. TheTVC as reported by the households revealed a consistent underestimationof costs (Table 8). This partly resulted from the non-inclusion of labor costsin the households’ farm input expenditure estimates and the costing of min-eral fertilizer and maize seed at subsidized prices. The government’s currentpolicy on smallholder agricultural development is, thus, perpetuating maizemono-cropping by making it cheaper to grow maize. This is contrary to oneprinciple of CA, which calls for crop rotations. Ploughing was reported ashaving the largest TVC.

Labor availability and costs are important but not the only considera-tions in households’ decision making on tillage systems. Ploughing remaineddominant despite its high-cost and low-net benefit, and the higher laborproductivity resulting from adoption of ripping. The tillage system preferredalso seemed to be influenced by sociocultural factors. The Tonga people ofsouthern and central Zambia are cattle keepers who prefer the use of oxenand the moldboard plough. Cattle and ploughing are integral parts of theirculture. Use of manual systems like hand hoe or basin digging is associatedwith poverty and local elites with large herds of cattle prefer to plough asthis is considered prestigious and an indicator of one’s place in society (P. H.Nyanga personal commmunication). An average of 88% of the CA farmers

TABLE 8 Total variable costs as reported by households

Basins Hand-hoe Ripping Ploughing

Total variable costs (ZMK/ha) 1,012,249 219,762 547,168 2,069,861

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of Southern Province had ploughed plots compared to only 46% in EasternProvince. About 28% of the CA farmers of Southern Province had rippedplots but only 10% in Eastern Province. The large difference between thenumber of households that had ploughed and ripped plots shows that itis not only inaccessibility to animal draft power that prevents householdsfrom switching to animal-based CA. Wichern et al. (1999) attributed part ofthe labor shortage in smallholder farming in Zambia to social norms thatrestrict optimal allocation of labor. Our focus group discussants reportedthat local social norms precluded the use of oxen by women and favoredthe allocation of a disproportionate amount of weeding activities to women.

Nyanga et al. (2011b) reported that household labor contributions fromwomen and children were found to be more than from men during handweeding. They further observed that herbicide application increased laborcontributions for men as herbicide application was the exclusive domain ofmen. In this study, we find that under CA, local social norms have minimizeddry season ripping as this is frowned upon as unnecessary over exertion ofoxen during a period when they are still weak from the dry season foddershortage.

Ploughing may have other benefits like weed control resulting fromsoil inversion. Sweet potatoes and cassava have traditionally been grown onridges. Household growing these crops continue to maintain CV tillage onpart of their fields. Groundnuts have traditionally been planted in hand hoesystems and increasingly in basins. The choice of crop, therefore, also affectsthe tillage system adopted. Majority of CA farmers in Zimbabwe were notpracticing crop rotation due to a general shortage of legume seed across thecountry and a common understanding that legumes should not be planted inbasins but in shallow furrows (Mazvimavi and Twomlow 2009). Factors likethese influence farming households’ decisions about which tillage system toemploy. Yet, CA promotion remains focused on increased labor productivityand higher gross margins.

The clear superiority of CA over CV in terms of profitability promptsthe question of why CA adoption is not more widespread in Zambia andthe region in general. The adoption of agricultural conservation technolo-gies among farming households in SSA is generally low. Many reasons havebeen advanced for this trend. Nowak (1987) argued that many farmers notaccepting these technologies lack the information and assistance neededto evaluate the economic and agronomic dimensions of the recommendedpractices. Others have argued that the goal of farming households is notjust profit maximization and automatic adoption of farming practices withhigher gross margins. Smallholder households have two separate goals ofhigher income and greater security, which are traded off in order to max-imize utility. The avoidance of the loss that may be incurred by a highoutlay of inputs may result in lower outlay of inputs than is suggested byprofit maximization. It may also be in terms of cropping patterns that do not

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correspond to the highest net return. Smallholder households target secu-rity as a goal because of precarious input and output markets, uncertaintyassociated with environmental variations, and the lack of crop insurancemarkets. Many smallholder households do nevertheless secure livelihoodstability with negligible loss of resource use efficiency through adopting cer-tain farming systems (Ellis 1993). For smallholder Zambian farmers, accessto subsidized mineral fertilizers and hybrid seed is quite variable. Access toagricultural credit and subsidized inputs by CA farmers was 45.8%, 38.3%,and 28.4% in the 2006–2007, 2007–2008, and 2008–2009 seasons, respec-tively. Households made decisions on where and when to allocate limitedresources resulting in, for instance, more mineral fertilizers being applied toploughed and ripped plots and more workers weeding these plots (Table 5).The perceptions of labor use by households may influence their decisionsmore than the actual demands of the different tillage systems.

CONCLUSIONS

Conservation agriculture is being promoted among smallholder Zambianfarmers as a minimum tillage technology that improves yields, saves labor,and increases the farmers’ income from agriculture. This study has shownthat while ripping utilizes significantly less labor, basin digging is laborintensive and is not labor saving compared to the conventional hand-hoetillage system. No differences were observed in the labor use at weedingtime between the CA and CV hand-hoe-based tillage systems, while morelabor was used for hand weeding ripped fields compared to ploughed fields.Overall, no labor saving benefit was observed for the complete farming cycleresulting from adoption of conservation agriculture.

Higher gross margins and returns to labor were reported under CArelative to CV. The drudgery associated with basin digging and increasedweed pressure under both CA subsystems permeated the focus group discus-sions and may have also influenced households’ decisions to allocate smallerareas to CA despite the acknowledged higher yields. Promotion of conserva-tion agriculture must, therefore, differentiate among households with severelabor constraints and those that have more labor at their disposal. Labor con-strained households may not adopt the basin digging tillage system to a largeextent despite its agronomic and economic superiority due to its drudgeryeffects. Improving farmers’ access to oxen would lead to labor saving at landpreparation and weeding phases of the farming cycle and reduce the majorlabor bottleneck experienced by smallholder farmers during these periods.Policy options or interventions that improve access to oxen could potentiallyhelp households deal with the labor constraints. Local institutions based onreciprocity such as farming circles are important in improving access to laborat low cost by many households.

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Conservation agriculture promotion can benefit from an increasedappreciation of socio-cultural context as opposed to the current exclusivefocus on its agronomic and economic benefits. The continued dominanceof conventional tillage in smallholder Zambian farming sector despite sig-nificantly higher net benefits from conservation agriculture points to theimportance of non-economic factors in the decision making of farminghouseholds. The input subsidy provided by the central government reducesthe expenditure on inputs and enables farmers to persist in using tillagesystems that would otherwise be loss making. It is, therefore, important toconsider the role and impacts of existing policy interventions on households’economic calculus when introducing technologies. The relative abundanceof land in rural Zambia encourages the expansion of cultivated land byhouseholds seeking to produce more food (Burke et al. 2010) instead ofintensifying through the application of more labor per area of land as isdemanded in CA manual system. Increased use of oxen would significantlyreduce the labor intensity during seasonal peak periods for both conven-tional and conservation agricultural systems. Any policy intervention thataddresses the challenge of access to oxen and other culturally appropri-ate labor saving technologies would potentially increase the agriculturalproductivity of the households in the areas studied.

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Are Smallholder Zambian Farmers Economists? A Dual analysis of farmers' expenditure in conservation...

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