Lessons from visualising the landscape and habitat implications of tree decline—and its remediation through tree planting—in Australia's grazing landscapes

Tree decline has been documented in farming and grazing landscapes around the world, with negative consequences for biodiversity and important ecosystem services. We have used solution-oriented transdisciplinary research to understand the possible consequences of scattered tree decline in Australia's temperate grazing landscapes, and explore appropriate management and policy responses. Here, we document the scenario modelling process that culminated our stakeholder engagement. We simulated tree decline and its consequences for landscape aesthetics and biodiversity, using photo-realistic visualisations based on photographs identified as significant by graziers, and empirically derived habitat relationships for a series of birds and bats. The results foreshadow dramatic visual and ecological impacts for the region. We also modelled the aesthetic and habitat impacts of fully costed remediation scenarios, including widespread scattered tree planting and densely seeding poor paddocks under temporary stock exclusion. The visualisations revealed to the research team that: (1) dense seeding has a more lasting impact for scattered trees than scattered planting; (2) the benefits of any kind of planting is short-lived if accompanied by conventional grazing practices; and (3) grazed woodlands are most at risk. The graziers to whom we presented our scenarios in the last of our stakeholder workshops responded well to both kinds of visualisations, but it was clear that the experience also extracted a cost. We reflect here on our methods and outcomes, and draw out lessons from our work for other studies of this kind.

► We modelled landscape and habitat implications of tree decline and fully costed planting scenarios. ► Tree planting alone will only ‘buy time’ in the short term (<50 years). ► Grazing management that supports natural tree regeneration will complement widespread planting. ► Woodland animals remain the most at risk under all our scenarios. ► Scenario visualisation improves communication within interdisciplinary teams as well as stakeholders, but can incur costs.