Flexible Boundaries in Biosecurity: Accommodating Gorse in Aotearoa New Zealand

The context of biosecurity has been theorised through attention to borders, boundaries, and expert processes of categorisation. This emergent literature represents biosecurity governance as brittle, unreflexive, and unresponsive. In contrast, biosecurity practices in New Zealand produce a complexity of semipermeable boundaries of control that are beginning to incorporate flexibility and sensitivity to the spatiotemporal geographies of indeterminate entities, and to changing and competing human values. Gorse ( Ulex spp), a woody, perennial shrub, was imported to New Zealand during the early stages of European settlement, and has been the subject of shifting biosecurity-related management practices for close to 150 years. Classified as a ‘pest plant’, gorse is currently subject to the biosecurity rationalities of internal pest management. Cost–benefit analysis and the ‘infestation-curve model’ are drawn on in the placement of gorse in a hierarchy of control categories within regional pest management strategies. This classification and control is negotiated between institutional and public values and rationalities within a formalised consultation process, and through the diffuse impact of public opinion. Gorse also plays an active role in the decision-making process, as its extensive distribution informs the allocation of control responses, and through its controversial role as a ‘nurse plant’ for native species. This paper therefore presents a challenge to emergent critical social scientific approaches to biosecurity, suggesting that we can learn something from the socionatural subtlety of policy making and implementation practices in New Zealand.