The federally endangered Arenaria cumberlandensis, or Cumberland sandwort, is found in only four counties in Tennessee and one county in Kentucky, all in the Cumberland Mountains area. It is a tiny plant that grows in sand in rockhouses that provide a cool, moist habitat. These areas were once used for shelter by native Americans and the plants are at risk from illegal digging by those searching for artifacts, as well as from recreational activities such as hiking and rapelling.

Seeds of this plant were sent to CREW from collaborators at the Missouri Botanical Garden. The seeds were germinated in vitro and tissue cultures of the shoots were established. These have been propagated and can be rooted, by transferring isolated shoots to rooting medium. Research at CREW established acclimation procedures that allowed the tissue culture-propagated plants to be transferred from the test tube to soil.

In 2005, plants produced at CREW were part of an experimental outplanting in Kentucky, conducted by staff at the Daniel Boone National Forest to determine the survival of these plants in a natural habitat. The plants were monitored in the summer of 2006, and over half of the original plants had survived the winter and many were flowering. The plants will continue to be monitored, and this information will be valuable in determining the adaptability of tissue culture propagated plants of this species for potential reintroduction projects in the future.