This article employs qualitative and quantitative evidence from primary social research in Ghana to examine the link between land tenure security and social identities (of wealth/income and gender), and how they condition farmers' investments in practices that contribute to the rehabilitation of tree biodiversity (agrobiodiversity). Statistical analyses of the significance of the effects of farmers' de jure land tenure security regimes, and income and gender on agrobiodiversity practices were inconclusive. The conventional causation link between investments and more secure formal land tenure rights, for instance, was confirmed in investments in four out of eight agrobiodiversity practices. Testimonial-based evidence of farmers provided a clearer concept of land tenure security and an explanatory framework about the interacting and complex effects of income and gender on land tenure security. The theoretical and empirical argument developed from these testimonies portrays land tenure as embodying negotiated social processes, influenced by gender and income of individuals, whereby breadth of land rights, duration of rights over land, and assurance of rights are established, sustained, enhanced or changed through a variety of strategies to shape tenure security. These processes – tenure building and renewal processes – are critical because all farmers have lingering anxiety about land tenure rights, even among farmers with more secure formal rights. Investments are made in agrobiodiversity practices as a strategy to strengthen land tenure security and thereby minimize anxiety, leading to reverse causation effects between land tenure, social identities, and investments.