How can biodiversity be preserved whilst securing the economic livelihood of smallholder farmers growing vanilla in Madagascar? There is a way, according to a new study. The research team shows that vanilla plantations established on fallow land do not differ in terms of yield from those established in the forest. Cultivation on fallow land also increases biodiversity there.How can biodiversity be preserved whilst securing the economic livelihood of smallholder farmers growing vanilla in Madagascar? There is a way, according to a new study. The research team shows that vanilla plantations established on fallow land do not differ in terms of yield from those established in the forest. Cultivation on fallow land also increases biodiversity there.