Trees May Not Be for the Birds

It’s a widely accepted thought that shade-grown coffee is better for native species, especially birds. For years, coffee farms have been able to obtain a “Bird Friendly” certification from the Smithsonian through planting shade trees in their coffee fields to provide natural habitat. However, a new study from the University of Delaware has found that we may be overlooking the most important factor: what kind of trees are being planted. The study found that non-native, exotic trees do little to nothing to attract birds and the insects they feed on, while native plants are the most effective. Results showed that birds exhibit a preference for specific native tree species, especially legumes.

“Farmers often select tree species that are beneficial to them and produce other products to sell in addition to coffee,” says Desirée Narango, a former UD grad student who worked on the study. “Some farms might prioritize walnut trees because they produce lumber or mango trees to produce fruit. There are so many choices. The goal of this project was to get more information to help farmers make that decision.”

Having native plants that attract native insects and birds creates biodiversity for better long-term sustainability. Growers can also benefit from the additional nitrogen provided by legumes, increasing coffee production.