Why do farmers plant more exotic than native trees? A case study from the Western Ghats, India

Farmers worldwide regularly plant trees to obtain provisioning and other ecosystem services. This practice has come under scrutiny by conservationists who perceive a reduction of biodiversity due to preferential planting of exotic trees. In order to reverse this preference for exotic trees it is necessary to identify the key drivers of exotic species planting and propose alternative species of interest to farmers. We examined this question in a coffee agroforestry landscape of the Western Ghats, India, a global biodiversity hotspot. We interviewed farmers regarding tree planting behaviour, preferences and constraints, and assessed the relative performance and value of native versus exotic species. Multivariate analyses were used with six species-level characteristics and four farm-level characteristics, to reveal the most significant predictors of planting frequency.The exotic species Grevillea robusta was planted 5.4 times more often than native trees. Individual species’ planting frequencies were most strongly related to their realised economic values, which was highest for G. robusta. Native trees with greater multipurpose utility value and stature were also more likely to be planted. Farm-level characteristics related to increased planting efforts were increasing climatic dryness, increased land area with native tree tenurial rights and farm size. However, farmers with a greater proportion of land under secure tree tenure planted fewer trees.We conclude that although native trees had higher multipurpose utility and potential economic value than the exotic G. robusta, the latter is grown more often due to existing legal frameworks that restrict private ownership and realising monetary value from native species. If current laws were amended to increase the economic benefits obtained from native trees, they are likely to be planted more often by farmers. We propose that our results can help in implementation of the recent National Agroforestry Policy of India, as well as inform agroforestry policies and practice elsewhere.