Removal, Propagation, and Transplantation of Michaux’s Sumac (Rhus michauxii) Colonies from the Infantry Platoon Battle Course, Fort Pickett –Maneuver Training Center, Virginia

Michaux’s sumac (Rhus michauxii Sarg.) is a rare and federally endangered, densely pubescent, rhizomatous shrub found in periodically disturbed habitats in the inner Coastal plain and piedmont of the southeastern United States. At Fort Pickett, conflicts between military training and Michaux’s sumac are uncommon. Current management of the Fort Pickett population restricts all military activity, with the exception of foot traffic, within colonies of Michaux’s sumac. However, the dynamic and constantly evolving military mission has resulted in range expansion and alteration thus isolating small colonies of Michaux’s sumac. At Fort Pickett, six colonies of Michaux’s sumac occurred within two active firing ranges. The goal of the research project was the careful excavation of Michaux’s sumac rhizomes from up to six small, isolated colonies on two active direct fire ranges at Fort Pickett, propagation of these individuals in a controlled greenhouse setting, and the subsequent transplantation of the propagated individuals to suitable habitat on Fort Pickett. In March 2017, while the plants were dormant, all rhizomes in colonies were excavated by digging with a hand trowel. We planted 168 bare rhizomes in 1-gallon plastic greenhouse pots with equal parts of peat, clay, and perlite, along with 25 grams of soil from the original colony location to ensure inoculation by native mycorrhizae. Approximately ½ of the individuals showed signs of stress and wilting by May of 2017. The source was a soil-borne pathogen, Rhizoctonia solani. All plants, including the healthy individuals, were treated with fungicides registered for control of rhizoctonia. On April 26-27, 2018, 39 of the greenhouse grown Michaux’s sumac were successfully planted in DF6. The remaining 20 grown outside under shade cloth will be planted in the fall of 2018. In July 2018, all 39-transplanted individuals were alive and vigorous with, 17 (44%) individuals producing female flowers and one (2.5%) male flowers. While these procedures were specifically researched and developed for the removal and transplantation of Michaux’s sumac stems from Range 12 and the IPBC, they can serve as the basis for any future propagation of Michaux’s sumac rhizomes for conservation and recovery.