As explained by Duffett, "The United States has been a pioneer in providing a governmental system for the protection of new plant varieties. The Plant Patent Act was enacted in 1930, and since that time Plant Patent protection has been secured for over 20,000 new varieties of vegetatively propagated plants. Several hundred additional Plant Patent Applications are being submitted by plant originators each year."
In the article, Duffett discusses an array of topics relating to the Plant Patent Act, including how "[t]he right provided to the owner of a US Plant Patent does not currently extend to 'essentially derived varieties' (EDV)" and therefore "the plant or parts thereof can be freely used by another for the development of other different plant varieties." Duffett also writes that as a result of newer legislation, such as the Plant Variety Protection Act, "[p]lant protection of broader scope than that provided by the original Plant Patent Act of 1930 is now a possibility."