The Portland Plant List is an integral component of the City of Portland's natural resource protection program. Portland's native plant policy is designed to ensure the continued viability and diversity of indigenous plant and animal communities, promote the use of plants naturally adapted to local conditions, and educate citizens about the region's natural heritage and the values and uses of native plants.
Native plants are part of the region's natural heritage.
In February 1986, the Greenway Plant List was developed in consultation with local ecologists, biologists and naturalists. Later that year, this list was adapted for the Columbia River Corridor area. Use of native plants from the list first became a requirement within the Willamette River Greenway Zones, and was later required within the Environmental Zones when adopted in 1989 for the Columbia Corridor. As part of that review, the TAC identified the need to create categories for native, nuisance and prohibited plants. In March 1997, the list was updated to reflect recent scientific findings on native plants in the region.