Genetic and Environmental Influences on Cold Hardiness of Native and Introduced Riparian Trees
Friedman, J. M., Roelle, J. E., and Cade, B. S. National Proceedings: Forest and Conservation Nursery Associations - 2011, p. 82-85. USDA Forest Service, Rocky Mountain Research Station, Proceedings RMRS-P-68. 2012.
To explore latitudinal genetic variation in cold hardiness and leaf phenology, we planted a common garden of paired collections of native and introduced riparian trees sampled along a latitudinal gradient. The garden in Fort Collins, Colorado (latitude 40.6°N), included 681 native plains cottonwood (Populus deltoides subsp. monilifera) and introduced saltcedar (Tamarix ramosissima, T. chinensis, and hybrids) collected from 15 sites from 29.2 to 47.6°N in the central United States. In the common garden, both species showed latitudinal variation in fall, but not spring, leaf phenology. This suggests that latitudinal gradient field observations in fall phenology are a result, at least in part, of the inherited variation in the critical photoperiod. Conversely, the latitudinal gradient field observations in spring phenology are largely a plastic response to the temperature gradient. Populations from higher latitudes exhibited earlier bud set and leaf senescence. Cold hardiness varied latitudinally in both fall and spring for both species. Although cottonwood was hardier than saltcedar in midwinter, the reverse was true in late fall and early spring. The latitudinal variation in fall phenology and cold hardiness of saltcedar appears to have developed as a result of multiple introductions of genetically distinct populations, hybridization, and natural selection in the 150 years since introduction.
Download this file:
Download this file
—
PDF document,
485Kb
Details
Author(s): Brian S. Cade, James E. Roelle, Jonathan M. Friedman
Publication: National Nursery Proceedings - 2011
Event:
Annual Meeting of the Western Forest and Conservation Nursery Association
2011 - Denver, Colorado
