RALEIGH, NC Christmas trees provide a significant source of revenue in southern Appalachia, resulting in millions of dollars in sales during the holiday buying season. The most popular species in the region is fraser fir, appreciated for its fragrance and consumer-friendly traits such as soft needles, strong branches, exceptional needle retention, and natural Christmas tree shape. Frasers, indigenous to isolated high-elevation mountains in southwestern Virginia, western North Carolina, and eastern Tennessee, are under attack by a pathogen called Phytophthora cinnamom, an insidious adversary that causes root rot, kills seedlings, and threatens serious economic losses for the region's Christmas tree industry. "Once a growing site is infested, the pathogen is nearly impossible to eradicate. Fir seedlings often die within 2 or 3 weeks from infection", noted John Frampton, a professor in the Department of Forestry and Environmental Resources at North Carolina State University. To develop planting stock that is resistant to or tolerant of Phytophthora cinnamomi, some growers in the southern Appalachian Mountains are turning to grafting practices, predominantly grafting fraser fir scions onto rootstocks of resistant momi or turkish fir. To aid growers in the region seeking effective grafting techniques, Frampton and his team designed a study, implemented by graduate student Haley Hibbert-Frey, to compare success rates of the traditional April grafting time with eight summer/early fall grafting dates. The study, published in HortScience, contains important recommendations for tree growers.
Fraser fir is usually grafted in April when the rootstock and scion are dormant. But spring is a busy time for growers, who would welcome the flexibility of performing grafting at other times of the year (e.g., late summer or early fall). The NCSU study compared success and growth of grafting fresh fraser fir scions onto turkish fir rootstocks during the traditiona
|Contact: Michael W. Neff|
American Society for Horticultural Science