Genetic data inform Yosemite National Park's apple orchard management guidelines

Abstract

Societal Impact StatementYosemite National Park, California, USA has hundreds of apple trees in orchards that were planted in the 1800s by local settlers. These orchards played a cultural role in the early history of the land that was to become a national park. Most of Yosemite’s orchards are well over one hundred years old and have reached the end of their lifespan. Genetic data has facilitated the assignment of cultivar names to historic apple trees within Yosemite and this information will be used to develop an Orchard Management Plan. Yosemite will use this Plan to balance orchard conservation with other necessities such as reducing human‐wildlife conflict from bears that enter developed areas to consume fruit from the trees.Summary Yosemite National Park, California, USA has hundreds of historic apple trees that were planted within orchards in the 1800s, prior to the establishment of the park. These apple trees have been a concern within Yosemite for decades because their fruit attracts bears and other wildlife into visitor recreation areas, causing undesirable wildlife–human interactions. Herein, 361 of Yosemite's apple trees were genotyped to determine cultivar identities. The cultivar names of 117 apple trees were identified by matching genotypic data with genetic data available for an apple cultivar reference dataset for the United States Department of Agriculture‐Agricultural Research Service (USDA‐ARS) National Plant Germplasm System as well as collections maintained by other sources. An additional 92 trees were determined to be likely cultivars because they matched genotypes in a reference set of trees whose identities are not known. A total of 152 trees had unique genotypes that did not match reference datasets. Cultivar information, made possible by having digital genetic information available, will allow for the preparation of a more comprehensive Orchard Management Plan. As such, park managers will be able use the Plan to more effectively make decisions about balancing orchard conservation with other park necessities, including eliminating the human–wildlife conflict that results from bears entering developed areas to feed on the fruit trees.