Living plant collections play an important role in conserving plant biodiversity. We collect and cultivate threatened tree species, like Quercus oglethorpensis (Oglethorpe oak), to learn about and safeguard important sources of tree genetic diversity.
Quercus oglethorpensis Duncan (Oglethorpe oak) is an endangered species native to the southeastern United States. It is threatened by land use changes, competition, and chestnut blight. The sparse distribution covers a linear distance of ca. 950 km, including several disjunct populations potentially harboring unique genetic diversity or adaptive variation. Protected populations in the Bienville National Forest (Mississippi), Oconee National Forest (Georgia), and Sumter National Forest (South Carolina) are regularly monitored and managed through a combination of techniques including burning and selective clearing. However, several additional populations were recently discovered in Alabama, primarily along right-of-ways or on private land where they should be considered vulnerable or at risk of extirpation. One documented population in Sumter County, AL, has already been lost to land clearing or logging activities. Traditional techniques such as seed banking are insufficient for ex-situ conservation of Quercus oglethorpensis due to the recalcitrant nature of the seeds. However, the species has been demonstrated as suitable for cultivation in a wide range of the United States and can be conserved ex-situ in the living collections of arboreta and botanical gardens.
In 2015, through a joint venture between the US Forest Service and American Public Gardens Association, seed and/or samples of scion wood were collected from populations of the species in Mississippi, Alabama, Georgia, and South Carolina and were propagated at The Morton Arboretum. In 2017, they were distributed to five arboreta and botanical gardens: Chicago Botanic Garden (Glencoe, IL), Starhill Forest Arboretum (Petersburg, IL), Holden Arboretum (Willoughby, OH), Donald E. Davis Arboretum of Auburn University (Auburn, AL), and Moore Farms Botanical Garden (Lake City, SC). Through cultivation in the Nationally Accredited Collections™ of these arboreta and botanical gardens, genetically diverse and representative germplasm of Quercus oglethorpensis will be preserved and potentially utilized in future reintroduction efforts.
Towards the end of 2017, a second phase of the project was attempted. Scouting was completed in the Bienville National Forest (Mississippi) and Caldwell Parish, Louisiana. Many trees were located, though had not produced acorns that season. Additional collecting efforts will be undertaken in hopes of bringing this germplasm into cultivation as well.
For more information, please see this article in International Oaks and the report and proceeding below:
Lobdell, Matthew. 2017. Quercus oglethorpensis W.H. Duncan: Ex-Situ Conservation Through Collaborative Cultivation. International Oaks. 28: 41-48.
APGA/USFS Tree Gene Conservation Partnership