Four out of five households in Malawi rely on farming as a primary source of income, most of whom cultivate maize (Zea mays). Disconcertingly, 63-80% of maize yield losses among these households are attributed to the emergence of invasive and parasitic weeds such as Striga (Striga spp.). A plethora of Striga-control practices (SCPs) have been developed and disseminated to smallholder farmers (cultivating < 2 ha). These SCPs are commonly evaluated at agricultural research stations prior to dissemination. Mixed results often arise later when they are implemented across the diverse agroecological and socioeconomic landscapes of smallholders. Many agree research will need to assess how SCPs perform under smallholder-conditions, and ultimately, how their uptake will affect emergence. The following dissertation is divided into three empirical studies. In the first essay, discrete choice experiments (DCEs) are used to estimate the percent of maize yield farmers are willing to sacrifice for different SCP attributes (e.g., labor, soil fertility). In the second essay, a seed bank stock and flow model (SB-SFM) is developed to assess emergence rates across different SCPs. In the final essay, results from the DCEs and SB-SFM are integrated within a system dynamics model (SDM) to simulate how environmental and socioeconomic parameters affect emergence across space and time. DCE findings highlight farmers are willing to sacrifice significant tradeoffs to implement SCPs that increase soil fertility and provide legumes. SB-SFM findings indicate the attachment phase and seed bank must simultaneously be addressed with multiple SCPs to suppress emergence over three to five years. Finally, alteration of different climate, farm-management and adoption parameters in the SDM underline that nutrient input subsidies and agricultural extension must be included in an aggregated effort to suppress the spread of Striga across the region.
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