Résumé
A citizen science module on the Wikwio web platform enables people to contribute their observations about weeds. The module is interconnected with expert-curated species pages, spatial and documents modules that foster interactions between citizen and scientific communities. These interactions improve the aggregation of scientifically validated data. For example, the citizen science module can inform scientists about the nature and level of occurrence of different weeds in different crop systems, their seasonality and distribution across the southern African region. In turn, the species pages module can inform extension agents and farmers about appropriate control measures for each species. Platform developers have built custom fields in the citizen science module to allow specific surveys to be commissioned by the scientific community. The comment history in the same module can enable dialogue between the citizen and scientific communities allowing people to pose questions directly to experts to which experts can respond with additional details and clarifications. Active, wide and large-scale participation from diverse stakeholders in agricultural research and practice is building a vibrant Wikwio community around a facilitating technology platform and a shared scientific practice.