Effects of lift date and photoperiod on budbreak and survival of 1-0 flowering dogwood (Comus florida L.) seedlings were studied under greenhouse conditions while survival was evaluated on plants transplanted in field plots. Seedlings were lifted from field beds on October 3, 1990; October 31, 1990; November 28, 1990; December 18, 1990; and February 5, 1991 (0, 63, 192, 357, and 851 chill hours, respectively (<7°C, 45°F)) and were placed in photoperiod chambers (10, 12, and 14 hr) constructed in a greenhouse or planted in the field under natural conditions. Increasing photoperiod under greenhouse conditions decreased the number of days to budbreak across lift dates. Photoperiod had no effect of survival. Survival of greenhouse plants was greater than 85% for all but the February lift date (72%). Survival of plants in the field decreased to 50% for the December lift date compared to >90% for both October lift dates. Mean survival across lift dates for the greenhouse and field plants were 88% and 77%, respectively. No differences in shoot growth or root regeneration were seen between treatments for greenhouse-grown plants. Results of these studies suggest that bareroot seedlings of flowering dogwood should be lifted and planted in the fall for optimal survival in the warmer areas of the southern United States.
Technical assistance of Bruce Tucker and statistical assistance of Ben Mullinix is gratefully appreciated. Donation of containers by Zarn, Inc., Reidsville, NC and potting media by Grace-Sierra, Milpitas, CA is appreciated.
3Associate Professor, University of Georgia, Extension Horticulture Department, P.O. Box 1209, Tifton, GA, 31793.
4Associate Professor, University of Georgia, D.B. Wamell School of Forest Resources, P.O. Box 1209, Tifton, GA, 31793.