PARENT SESSION
Oral Session 12: Restoration Ecology I: Streams and Wetlands.
Presiding: M Wu
Monday, August 2, 8:00 AM to 11:30 AM, Meeting Room D 133.
Germination and dormancy cycling in 10 Carex spp.: Implications for prairie wetland restoration.
Kettenring, Karin*,1, Galatowitsch, Susan1, 1 University of Minnesota, St. Paul, MN
ABSTRACT- Since the mid-1980s, thousands of acres of prairie wetlands have been restored. Recent studies have shown that the Carex spp. common in natural wetlands are not returning to restorations. To restore the Carex diversity, seeds will need to be sown into restorations. However, there is little existing data on Carex germination and dormancy cycling — information critical to maximize Carex establishment. In a growth chamber experiment, we investigated germination and dormancy cycling in 10 Carex spp. To look at dormancy cycling, we incubated Carex seeds in a growth chamber that was adjusted seasonally to mimic current field conditions. By looking at germination rates initially versus after the seeds had been through the winter conditions, we could determine the dormancy state of mature seeds. To look at germination rates under different temperature regimes, we incubated seeds under temperature regimes that mimicked summer, winter, late spring/early fall, and early spring/late fall conditions. We found that some species — like C. molesta — were nondormant at maturity while others species — like C. comosa — were partially dormant. In addition, some species had the ability to germinate under a wide range of temperature regimes while other species were only able to germinate under the summer temperature regime. Findings from these studies indicate that in wetland restorations, restorationists will need to consider the timing of seed sowing to ensure dormancy break in some species and to get maximum seed germination for all species. In this way, restorationists will be able to get the most out of an often limited seed supply and attempt to restore the Carex diversity common in natural wetlands.
Key words: seed germination, prairie wetland restoration, Carex, seed dormancy