The Indiana Terrestrial Plant Rule (312 IAC 18-3-25) designates 44 species of plants as invasive pests. This rule makes it illegal to sell, gift, barter, exchange, distribute, transport, or introduce these plants in the State of Indiana. This rule goes into effect in two stages. As of April 18, 2019, it is illegal to introduce plant species on this list not already found in Indiana. Plant species already in trade will be prohibited from sale one year later (April 18, 2020).