Dormant one-year-old roots of American ginseng (Panax quinquefolium L.) were exposed to a range of stratification temperatures and times to define limits for these parameters and to quantify their effect on terminating rest when placed in a growing environment. Effective storage temperatures tested ranged from 0° to 9°C. A low percentage of roots produced tops with as few as 30 days of stratification; however, 60 to 90 days were required for 100% emergence. The number of days to emergence, after planting, decreased with increased time in stratification through the maximum storage time of 120 days. The number of days of dormancy (days in stratification + days to emergence) averaged 126 and was relatively constant over the range of effective temperatures and periods of stratification. The minimum predicted period of dormancy was 116 days and was associated with a derived 70 days in storage (1680 hr) at 3.1°. Root growth rate, after emergence, was greatest following 105 days of stratification.
Professor. Mailing address: Mountain Horticultural Crops Research Station, 2016 Fanning Bridge Road, Fletcher, NC 28732-9628.
Received for publication 19 Apr. 1985. Paper no. 9819 of the Journal Series of the North Carolina Agricultural Research Service, Raleigh, NC 27695-7601. The cost of publishing this paper was defrayed in part by the payment of page charges. Under postal regulations, this paper therefore must be hereby marked advertisement solely to indicate this fact.