Native Plant Species Pilot Program Act of 2020 This bill establishes a pilot program for native plant species and a study on the cost-effectiveness of using native plant materials to carry out land management activities on federal lands. The National Park Service (NPS) shall establish a pilot program in at least two NPS regions to promote the use of native plant materials. The NPS shall conduct a study to determine the cost-effectiveness of using native plant materials in land management activities on federal lands under the jurisdiction of the NPS or other federal land management agencies.