Silvopastoralism in New Zealand’s highly erodible hill country is an important form of erosion and sediment-loss control (Fig. 1). Despite a long history in improving sustainable land management and soil conservation, there has been relatively little quantitative work to establish the effectiveness of space-planted trees in reducing shallow landslides at farm to catchment scales. This is largely due to the lack of spatially explicit data on individual trees (e.g. location and species). Moreover, there is limited information related to the spatial extent of impact that trees have on their surrounding environment (e.g. root system architecture data).