When Are Native Species Inappropriate for Conservation Plantings?

Abstract

Summary No species, native or nonindigenous, should be used in planting programs without considering its invasive potential (i.e., by risk assessment). Increased dispersal from tree plant-ing can be the catalyst in converting grassland to woodland when accompanied by change in ecosystem keystone pro-cesses. Consequently, tree planting in North American prai-rie represents a contradiction to conservation of imperiled prairie ecosystems. Indeed, woody plant invasions resulting from introduction of species for aesthetics, conservation, and agroforestry is a global problem. 16,17 If conservation of native species and native grasslands is considered an impor-tant goal in conservation, then programs and activities that facilitate the spread of invasive species, both native and nonindigenous, should be curtailed.