Purchase Knob's old apple trees: how the Park Service is saving and identifying them

On a grassy summit in Great Smoky Mountains National Park, more than 30 apple trees have survived well over a hundred years with no one tending them. The National Park Service recognizes them as possibly some of the oldest fruit trees in any park unit, and is now starting to care for them.

Assessing an apple tree at Purchase Knob in 2022. NPS photo.

A mountain farm

In 1874 John Love Ferguson acquired "Purchase Mountain," near the Tennessee and North Carolina border, for $447 and one horse. Ten years later the family built a cabin and a barn and cleared land for crops and livestock. Cultivated apples did well in the cool climate. Good farmland is scarce in Appalachia, so the Fergusons used the high elevation and open meadows, raising cows for butter and growing fruit for the local market. Apples grown at high elevations, with hot days and cool nights, were known for the best quality and flavor, and the conditions suited both production and storage. In a 1966 interview, John's son Hugh Glenn Ferguson, who lived to 99, recalled picking apples as a boy and hauling 40 bushels per wagonload to market in nearby Waynesville.

The park was established in 1934, mainly to protect forest and natural resources, and management generally let the forest recover from logging and farming, so many farms, mills, orchards and schools disappeared. Purchase Knob stayed private, next to the park boundary, until the mid-1990s, when its owners donated it to the Park Service. It is now one of the Park Service's National Research Centers, the Appalachian Highlands Science Learning Center.

A Landscape Management Plan, produced in 2014 with the Park Service's Olmsted Center for Landscape Preservation, drew on historical records, field study and talks with former owners and neighbors. It identified apple trees to protect, some from the late 1800s. They are the only known original apple trees on the North Carolina side of the park apart from a handful in the Cataloochee area, and their survival shows their resilience to frosts, storms, pests and disease.

Opening the landscape again

At 5000 feet, the open fields have become rare in Southern Appalachia, and they now shelter species of concern such as the Golden-Winged Warbler. Managing the knob means balancing care for fruit trees and farm remnants against a fragile ecosystem and wide views, and dealing with encroaching growth, access, research, interpretation and climate change.

Vegetation management crew members clear encroaching plants around the base of an apple tree. NPS photo.

Fruit trees need at least eight hours of sunlight a day in the growing season. In 2022 the park's forester and its Vegetation Management Crew cleared brush, felled overhanging and encroaching trees and mowed in early spring, and removed stump sprouts in the fall. Later work could include removing dead, diseased and damaged limbs, pruning for balance and perhaps cabling weak limbs.

DNA testing

Documentation during DNA sampling at Purchase Knob in early 2022. NPS photo.

With Washington State University's horticulture department in Pullman, the park took six samples for DNA testing to identify the old trees' varieties, which differ in ripening time, skin and flesh color and flavor. Many 19th-century varieties are now rare or gone from commercial markets. The results, which go into a national database of apple genetics at the university, can show whether several trees share a variety, whether any are rare older varieties or originated locally or are unique to the national parks, and whether they ripened early, mid-season or late.

Challenges remain. The trees are scattered orchard remnants, not planted in a grid, so some could be overlooked. It is also hard to tell trees planted long ago from seedlings spread by wildlife, and some seedlings may have served another purpose, such as rootstock for grafting or cider-making. For now the park's forester said the Park Service treats all mature fruit trees as potentially significant cultural resources.

What the tests found

The article was updated in March of 2024 with the results. Most existing trees probably began as seedlings on the site and were kept because they bore good fruit; several, including a Magnum Bonum, were probably trained and maintained for fruit quality. Caring for seedlings that bore palatable fruit reflects the orchard's remoteness, balancing subsistence use and commercial practice.

Evidence for these varieties is direct for Magnum Bonum; the others were found as the parents of five trees whose own varieties were not identified. The article says more varieties were very likely grown here, and the park plans to sample more of the old trees.

Sources

• National Park Service, "Investigation and Stabilization of Apple Trees at Purchase Knob" (https://www.nps.gov/articles/000/great-smoky-mountains-purchase-knob-orchard-stabilization.htm), updated in March 2024 with the DNA results. Staff are named by role only, a group portrait is left out, and the source's "Olmstead Center" is spelled here as the Olmsted Center.
• National Park Service's page; rewritten in hubnx's own words.