2018 ASHS Annual Conference

There were thousands of apples planted in Wyoming’s orchards and homesteads in the 1800s, many of which are still alive today. The purpose of this research was to identify heritage apple cultivars in Wyoming using genetic fingerprinting (microsatellite) techniques and then use this information to suggest candidate cold-hardy cultivars for specialty crop and breeding programs. Leaf samples were collected from 510 heritage apple trees from 88 sites in 18 cities across Wyoming. In addition, known cultivars from the USDA-National Plant Germplasm System, Seed Savers Exchange and Washington State University apple collections were used as standards to determine cultivar identities. Overall, 335 (65%) of the previously unidentified apples trees matched to 47 known cultivars. Fifteen of these known cultivars comprised over 80% of the samples that were identified, with 14 of those cultivars developed in states and countries with average temperatures or winter conditions similar to Wyoming (including Minnesota and Russia). Seventy one of the heritage trees were the cultivar, ‘Wealthy’, and other commonly identified cultivars were ‘Haralson’, ‘Patten’s Greening’, ‘Yellow Transparent’, ‘Northwestern Greening’ and ‘McMahon’. The popularity of ‘Wealthy’ may be the result of its promotion in Agricultural Extension Bulletins from 1870-1940 and its frequent use in developing novel varieties for Wyoming’s climate. Although many original Wyoming heritage apple trees are reaching the end of their lifespan, many surviving trees continue to produce fruit. These results provide insights into possible cultivars that could be grown in Wyoming and also in other states with similar harsh growing conditions.