On August 28, 2026, the U.S. Department of Agriculture’s (USDA) Animal and Plant Health Inspection Service (APHIS) advised the public of its determination that Darling 54 American Chestnut (Castanea dentata), which was developed using genetic engineering for tolerance to the fungal pathogen, Cryphonectria parasitica, is no longer considered regulated. 91 Fed Reg. 55510. According to the notice, APHIS’ determination is based on its evaluation of information and data submitted by the State University of New York College of Environmental Science and Forestry (ESF) in its petition for a determination of nonregulated status, available scientific data, a plant pest risk assessment (PPRA), and public comments received in response to previous notices announcing the availability of the petition for nonregulated status and a draft PPRA. Based on APHIS’ evaluation in the PPRA, information and data submitted by ESF in its revised petition, available scientific data, and public comments received in response to the original and revised petitions and draft PPRAs, APHIS states that it has determined that Darling 54 is unlikely to pose a greater plant pest risk than the nonmodified comparator and therefore is no longer subject to its regulations in 7 C.F.R. Part 340 governing the introduction of certain organisms developed using genetic engineering. The change in regulatory status was recognized as of August 28, 2026.