risky task due to their large size and potentially erratic behavior. According to Alesina, Giuliano and Nunn (2013), the plow requires significant upper body strength, and bursts of power, both to pull the plow and control the animal that pulls it. Women are thus commonly considered less suitable for the task–though there is substantial heterogeneity in adherence to this norm. We find that our observed negative treatment effects on the time women and girls spend on household plots are predominantly driven by households in districts with relatively lower female involvement in oxen tasks. Nationally-representative data shows that matrilineal ethnic groups are less prevalent in these districts, and norms are less gender-egalitarian. In these more conservative communities, women shift to working off-farm once oxen are introduced. These empirical patterns align with predictions from our simple model of time allocation under social prescriptions, which builds on Kevane and Wydick (2001).

There are three main contributions of this paper. First, we provide the first experimental evidence on the impacts of animal traction, and the first experimental evidence on the effects of agricultural mechanization as a whole in Sub-Saharan Africa–building on a rich literature that has examined the adoption and use of labor-saving agricultural technology in the region (Pingali, 2007; Owolabi et al., 2012; Guthiga, Karugia and Nyikal, 2007; Williams, 1997). The existing non-experimental research lays out several key stylized facts about animal-traction mechanization, including minimal yield gains, an increase in land under cultivation and devotion of the expanded land to market crops, as well as a reduction in labor required during the land-preparation period (Pingali et al., 1987). More recently, studies of rice production in Cˆote d’Ivoire highlight how mechanizing land preparation can contribute to agricultural intensification, thereby raising productivity (Mano, Takahashi and Otsuka, 2020), especially when agro-chemicals and mechanized land preparation are combined (Aihounton and Christiaensen, 2023). Within the limited literature demonstrating experimental evidence in developing country settings, our paper is most closely related to a recent study in Karnataka, India, which demonstrated that subsidized access to rental equipment markets lowered labor demand across all farming stages, and disproportionately so in stages not being mechanized, leading to an increase in non-agricultural income (Caunedo and Kala, 2021).

Our second contribution is to examine how the time-use impacts of mechanization vary within the household, speaking to the broader literature on the intra-household consequences of technology adoption (Wodon and Blackden, 2006; Bryceson, 2019; Doss, 2013; Theis et al., 2018). This analysis is particularly important in contexts where the social norm goes against women using the technology: in our case, plowing with oxen (Fisher et al., 2017; Starkey, 1995; Wanjiku et al., 2007). Modern agricultural technologies can affect women’s farm labor negatively, facilitating shifts to new tasks or activities, or positively, depending on the context. Importantly, these shifts have the potential to drive structural transformation if they free up women’s time for other market-based activities (Goldin and Sokoloff, 1984; Dinkelman and Ngai, 2022). This tension highlights that ‘one norm does not fit all’: sexist beliefs or practices limiting women’s engagement in one economic domain can spur women’s engagement in other economic domains.

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