An Annual Research Symposium
The 15th-annual Science Day will be February 5, 2015, from 9 to 11:30 a.m. The symposium on current research at the Arboretum includes talks, a keynote address, and posters. The event is free and open to the public. Details about presenters and topics will be available in early 2015.
Students conducting research at the Arboretum took the opportunity to describe their studies and hone their communication skills by presenting talks and posters at the Arboretum’s annual Science Day on February 13, 2014. In addition, Botany Professor Tom Givnish demonstrated how Noe Woods has changed over 57 years of continual monitoring. The presentations highlighted selected species, showing how a single member of a community responds to many drivers. The species in the Arboretum spotlight were ticks (along trails), orchids (Greene Prairie), buckthorn (Lost City), tussock sedge (Teal Pond Wetland), and black oak (Noe Woods).
An inquisitive audience of more than 100 naturalists, nature enthusiasts, guides, and neighbors asked dozens of excellent questions. Abstracts of the presentations are available as a PDF in the left sidebar of this page. Here’s what we learned:
How does buckthorn (Rhamnus cathartica) affect seed predation by small mammals? Kristina Bartowitz, MS student in Environmental Studies advised by John Orrock (Zoology), described experiments she plans to conduct in the Lost City this summer. Bartowitz will test the effect of canopy cover (because buckthorn extends the growing season of native shrubs by producing leaves earlier and retaining them longer), leaf litter decomposition (because buckthorn litter decomposes rapidly due to high nitrogen concentrations) and allelopathy (because emodin emitted by buckthorn inhibits native understory plants). Which conditions will affect small mammal consumption of native woody-plant seeds that she will supply to Arboretum study sites? Come again next year, when we hope to hear the answer!
What’s the best way to restore a sedge meadow near Teal Pond? Tussock sedge has emerged as our best bet for wet meadow restoration, because it supports plant diversity, takes up added nitrogen and stores carbon (see leaflet #22). Dr. Jim Doherty, a recent Botany Department graduate advised by Joy Zedler, presented two years of experimental efforts to restore tussock sedge to Teal Pond Wetland. By providing varied topography (mounds and depressions) and allowing dry (2012) and wet (2013) years to vary the growing conditions, Doherty demonstrated how bet-hedging helps ensure that some of the plantings will grow at least some of the time. Doherty’s dissertation is archived at the Memorial Library and the Arboretum; publications are forthcoming.
What should we call our highly variable orchids? Some think that wide variation in plant and flower size and shape indicates hybridization, but Matthew Pace, Botany PhD student advised by Ken Cameron, found only limited evidence for hybridization among Midwestern Spiranthes (North America’s 2nd largest orchid genus, with 7 spp. in Wisconsin). Pace’s exploration of DNA among potential parents, hybrids and backcrosses failed to support the hybridization hypothesis in most cases. But, his sampling in Greene Prairie indicated one hybrid, namely Spiranthes magnicamporum x S. cernua. Greene Prairie is the only place where he found hybrid plants, and he found them in “short, damp prairie.” DNA analysis is a wonderful tool for settling debates about hybridization, but it doesn’t guarantee a simple resolution.
What should we do about ticks? A graduate student in the School of Medicine and Public Health advised by Susan Paskewitz, Jordan Mandli provided natural history, ecological, and human health aspects of ticks, including the newly recorded lone star tick from southeastern United States. If you see this one at the Arboretum (identifiable by a white star-shape blotch on its reddish-brown back), please contact Brad Herrick (firstname.lastname@example.org). Mandli’s advice: check yourself after outings, and use tweezers to remove ticks that burrow into your skin.
How has black oak fared over 57 years of monitoring Noe Woods? When Bruce McCune and Grant Cottam published the first long-term study of Noe Woods in 1985, they found that black oak (Quercus velutina) was dominant, its basal area was declining, that oak wilt contributed to its mortality, and that it failed to regenerate where fire was suppressed. Now, with 30 more years of data accumulated (57 years total), Tom Givnish concludes that fire is essential for dry forest to keep an open canopy, and that the closed canopy favors less fire-tolerant species and more shade-tolerant species, but that disease is just one of the drivers of forest succession. His predictions for the future are that oaks will be lost, along with their diverse understory vegetation; however, some attributes, such as tall trees with hollows for nesting, would have conservation value. His call to action: Restore rare, highly diverse oak savannas, using Noe Woods as a laboratory to learn how to create diverse oak savanna.
Posters on display:
- Landscape effects on Spotted Wing Drosophila infestation in raspberries – Emma Pelton, MS student, Departments of Agroecology and Entomology, UW–Madison
- Effects of climate change and land cover on the subnivium, a seasonal refuge beneath the snow – Sonia Petty, undergraduate, Department of Forest and Wildlife Ecology, UW–Madison
- Do weather and habitat interact to create energetic refugia for wintering birds? – Chris Latimer, PhD student, Department of Forest and Wildlife Ecology UW–Madison
- Wetland restoration research at University of Wisconsin Arboretum – Jim Doherty, post-doc, Department of Botany, UW–Madison
- Adaptive restoration in and near the UW Arboretum: Teal Pond Wetland, Lower Greene Prairie, and Harlan Hills Meadow – Botany 670 class projects, UW–Madison
—summarized by Dr. Joy Zedler