2004 Janet Meakin Poor Research Symposium

Celebrating 10 Years of the Plant Conservation Alliance:
Conservation and Restoration of Plant Communities

Abstracts -- Poster Presenters



Post-fire restoration of the Great Basin Intermountain region: Part II Seed Biology. Jeremie Fant*, Andrea Tietmeyer and Kayri Havens. Chicago Botanic Garden, 1000 Lake Cook Road, Glencoe, IL 60022. (847) 835-5440.

The Great Basin Intermountain region encompasses approximately 200,000 acres of land west of the Rocky Mountains, much of which is overseen by the Bureau of Land Management (BLM). The native plant communities of this region have become increasingly degraded due to overgrazing, the presence of non-native invasive species (i.e. cheatgrass [Bromus spp.]), and wildfires. In their efforts to restore and revegetate degraded areas after wildfires, the BLM has implemented a program to resow areas with seed from a mixture of species. With the goal of increasing the use of native species in these seed mixtures, a key question is how important seed source is in the success of the seed planting. As the Great Basin region covers a vast area and includes a wide variety of physical and biological conditions, it is possible that seed collected from one area will not be suited for the conditions in another. Consequently, the BLM has engaged the Chicago Botanic Garden to assist in addressing this question. For this, we are using six species from two of the most common genera in this region, Penstemon spp. (beardtongue) and Eriogonum spp. (buckwheat). In the first year of this multiple-year study, we have investigated various aspects of seed biology (maternal contribution, stratification period and germination rates) to determine whether local differences exist for these fitness traits. We present results for two of the six study species, indicating that seed responses vary significantly among population, and that these responses may be explained by the length and severity of winter experienced at the collection site. Relevance of these findings to restoration activities using seed will be discussed.

Effects of smoke on prairie seed germination. Britt Forsberg, Lara Jefferson*, Marcello Pennacchio and Kayri Havens. Chicago Botanic Garden, 1000 Lake Cook Road, Glencoe, IL 60022. (847) 835-5440.

It is well known that fire plays a role in the maintenance of the tallgrass prairie ecosystem. Fire helps maintain species richness and discourages the growth of invasive species. Many species of prairie plants are adapted to periodic fire. Heat is required for the germination of seeds of some prairie species. such as Iliamna remota (Chasan and Hart, 1996), as well as for seeds in other fire-prone ecosystems. Smoke stimulated germination in California chaparral, the South African fynbos, and Western Australian scrub, but the effect of smoke on prairie seeds had not previously been investigated. This study treated 11 species and three hybrid cultivars of prairie plants with aerosol smoke for varying lengths of time to identify species stimulated by smoke. The results were mixed; some species experienced increased or decreased germination percentages, and others were unaffected. The results of this study may benefit both restoration efforts and the horticultural trade.

How pollen age, style age, and self-incompatibility influence pollination in fragmented populations. Echinacea angustifolia. Jennifer Ison* and Stuart Wagenius. Chicago Botanic Garden, 1000 Lake Cook Road, Glencoe, IL 60022. (847) 835-5440.

The tallgrass prairie of North America was once a vast, continuous habitat, but it is now fragm8ented into small, isolated remnants. Fragmentation affects pollinator dynamics, resulting in pollen limitation in many prairie species with inbreeding avoidance mechanisms like self-incompatibility. The common perennial Echinacea angustifolia, the narrow-leaved purple coneflower, experiences an increase in pollen limitation as remnant size decreases. We tested the hypotheses that the duration of pollen viability and style receptivity, and the mechanics of self-incompatibility, play a role in pollen limitation in E. angustifolia. We conducted three experiments: one with aging pollen and fresh styles, another with aging styles and fresh pollen, and one where we examined pollen tube growth in four pollination treatments at specific times after pollination. We found that freshly emerged pollen fertilized in 50% of ovules, but by day 7 in only 27%. Similarly, we found that style receptivity decreased over time. As styles aged, seed set decreased from 76% on day 1 to 36% on day 9. We found all pollen produced pollen tubes, but compatible pollen did so at a significantly higher rate and set significantly more seeds than incompatible pollen. These results show that pollen viability and style receptivity decrease over time, thus limiting the opportunity for plants in fragmented populations to receive compatible pollen.

Invasive species. Ellen Jacquart, Indiana Chapter of The Nature Conservancy, 1505 N. Delaware Street #200, Indianapolis, IN 46202. (317) 951-8818.

The Midwest Invasive Plant Network (MIPN) is a diverse group of organizations dedicated to addressing the threat of invasive plants in the Midwest. The group's mission is to address the problem of invasive plants and their threat to the Midwest region's economy, environment, and human health by providing leadership, facilitating information development and exchange, and coordinating regional efforts.

Currently, a lack of coordination among groups working on invasive plant species projects in the Midwest has led to a tremendous duplication of effort and missed opportunities for collaboration at the regional level. The MIPN proposes to facilitate that collaboration and information sharing and help to energize the local projects going on throughout the Midwest.
The poster will describe the goals of the MIPN, which include: producing a list of invasive plant species mapping and inventory projects in the Midwest (including information on associated early detection-rapid response projects) and a recommended data standard to be followed that will be communicated to all involved in such projects; providing regional educational materials to raise awareness regarding invasive plant species in the Midwest; creating a website decided to invasive plant species issues in the Midwest, which will feature the products mentioned above as well as information on legislative efforts, funding opportunities, control techniques, current research, and other information specific to the Midwest; and regular communication between invasive species researchers, managers, and other interested in or affected by this topic through a listserv, conference calls, workshops, and meetings.

Carbon addition and its effects on soil nitrogen and prairie development. Cynthia Kadlec1, Dave Sollenberger2 and Louise Egerton-Warburton2. 1Elmhurst College, 190 Prospect Avenue, Elmhurst, IL 60126. (630) 617-3500. 2Chicago Botanic Garden, 1000 Lake Cook Road, Glencoe, IL 60022. (847) 835-6915.

Restoring prairies is essential to the preservation of grasslands that were once common to Illinois. A practice often associated with restoration is cultivation of the topsoil. This disturbance causes an increase in soil nitrogen (N) levels, which provides weedy species a competitive advantage over native species or space and resources. At the Chicago Botanic Garden's Dixon Prairie, we are studying the effects of incorporated materials with high C:N on soil where N levels are high. We hypothesized that carbon (C) addition will stimulate soil microbe activity, thereby immobilizing soil N, causing a temporary decrease in soil N levels. In addition, we predict floristic quality and native plant biomass should increase with decreasing soil N. In order to test our hypothesis, the prairie was divided into sixteen plots, each containing a control or one of three amendments in the form of wood chips, wood shavings or a combination of chips and shavings. From these 16 plots data for NO3 and NH4, biomass, and floristic quality were collected. Our results showed that in 2003 and 2004, C addition reduced available N, except for plots with shavings. Floristic quality increased, especially in the chips and shavings/chips treatments. We also found that in 2003 and 2004, C addition increased native plant biomass in all plots and decreased all non-native plant biomass except for the control. Our data indicates that soil carbon addition may be useful in controlling weedy species in the early stages of prairie restoration.

Assessing the competitive ability of Japanese stilt grass, Microstegium vimineum. Stacey A Leicht*, John A. Silander, Jr. and Kate E. LeRose. University of Connecticut, Department of Ecology and Evolutionary Biology, 75 North Eagleville Road U-3043, Storrs, CT 06269. (860) 486-4157.

Microstegium vimineum (Japanese stilt grass) is an invasive grass in the eastern half of the United States that can form dense monocultures in forest understories, displacing native species. Though the loss of native species has been observed in the field, the actual competitive ability of this grass has not been reported. Microstegium vimineum was competed under controlled environment, greenhouse conditions against Lolium perenne spp. multiflorum (annual rye grass) and Muhlenbergia mexicana (Mexican muhly) in varying density ratios in full and low light treatments. Microstegium vimineum had a greater relative growth rate, as well as greater aboveground biomass than both competitors in both light treatments. The high competitive ability of M. vimineum, especially in low light conditions, makes it a particularly insidious invasive species with the potential to spread aggressively across the landscape of Eastern North America.

Plants of Concern: Volunteers monitor rare species in a standardized regional program (Northeast Illinois). Susanne Masi1* and Lailah Reich2. 1Chicago Botanic Garden, 1000 Lake Cook Road, Glencoe, IL 60022. (847) 835-5440. 2Huff and Huff, Inc., 512 W. Burlington, Lagrange, IL 60525. (708) 579-5940.

Plants of Concern (POC), launched in 2000, is a regional, long-term monitoring program for state-listed and other rare plant species in Northeast Illinois. It is a flexible collaboration of public and non-governmental conservation agencies, landowners and volunteer groups, guided by an advisory group of land managers, scientists and volunteers. A key program component is training volunteers to collect data as a means of leveraging scarce landowner resources. POC monitoring utilizes standardized protocols to ensure consistency of data and combines population censusing with assessment of threats and invasive species. A major goal is to relate population trends with management practices, in order to provide feedback to managers following an adaptive management process. Since 2001, 53 volunteers monitored 281 occurrences of 122 species, working with 51 landowners at 112 sites. Data indicate that a majority of populations of rare species suffer high invasive species presence and other stresses. They also indicate one or more management activities being implemented within a significant number of populations. The poster focuses on program concept and data analysis results over three years of monitoring. POC is coordinated through the Chicago Botanic Garden and is funded by Chicago Wilderness, a regional conservation coalition, and by the Corporation for Open Lands (CorLands).

Clonal and spatial genetic structure of natural and restored populations of Ammophila breviligulata (Poaceae). Eileen Sirkin, Susanne Masi and Jeremie Fant*. Chicago Botanic Garden, 1000 Lake Cook Road, Glencoe, IL 60022. (847) 835-5440.

This study investigated the current methodology for the restoration of dune systems using Ammophila breviligulata (Marram Grass, American Beachgrass). We collected samples from well-established spontaneous Illinois populations, planted populations and suppliers of Ammophila breviligulata rootstock. We were able to show that genetic diversity in natural, well-established populations varied from two clones to up to eight clones in the same area. On closer examination of the spatial distribution and spread of individual clones, it was found that in more heterogeneous environments with lower plant densities, there were often multiple genotypes over a small spatial scale, while more dense stands would be comprised of a single large monomorphic stand. With planted populations the level of genetic diversity tended to be lower than that of natural populations, with a more even distribution of clones and fewer genotypes over small spatial scale.

Spatial patterns of Echinacea angustifolia pollinator abundance and diversity in a fragmented landscape. Stephanie Pimm* and Stuart Wagenius. Institute for Plant Conservation, Chicago Botanic Garden, 1000 Lake Cook Road, Glencoe, IL 60022. (847) 835-5440.

To examine the effects of habitat fragmentation on the abundance and diversity of pollinators visiting narrow-leaved purple coneflower (Echinacea angustifolia), a common prairie plant, we observed and collected insect visitors on Echinacea flowers in 20 prairie remnants in western Minnesota. Echinacea populations within these remnants ranged in size from 3 to approximately 4500 flower plants, and their isolation and landscape context differed. We visited each site 3-4 times during the flowering season, and observed 5 randomly selected flowering plants during each visit. During observations we recorded descriptions and behaviors of all insect visitors, and collected a subset of visitors for identification purposes. Native bees and syrphid flies (Syrphidae) accounted for the majority of insects collected on observed Echinacea flowers, with 9 genera of bees from 4 different families (Halicitidae, Anthophoridae, Andrenidae, Megachilidae) represented in our collections. We present data on the spatial patterns of Echinacea pollinator abundance and diversity.

Effects of self versus outcross pollination on pollen tube growth in Platanthera leucophaea. M. Mercedes Stickler1, Kathryn Theiss2* and Pati Vitt2. 1Northwestern University, Evanston, IL. 2Institute for Plant Conservation, Chicago Botanic Garden, 1000 Lake Cook Road, Glencoe, IL 60022. (847) 835-6972.

Faced with fragmented habitats and low self-seed viability, the Eastern Prairie Fringed Orchid, Platanthera leucophaea, has been placed on the federally threatened species list. While several experiments (see for instance Bowles, 2002) have examined the viability of self versus outcross seed, there is a serious need to understand why this phenomenon occurs in order to create the most effective conservation strategy.

This study compares the effects of self versus outcross pollination on pollen tube growth in P. leucophaea and attempts to explain the observed lower viability of selfed seeds. Eighty plants from a population in Iowa were randomly chosen for the experiment, forty of which were self-pollinated and the other half outcrossed. Individual flowers were fixed in FAA at one of four randomly assigned collection times, stained with aniline blue, and then examined under fluorescence microscopy.

In addition to qualitative data that illustrate several irregularities in self pollen tube growth as compared to outcross tube growth, the quantitative results of both an Analysis of Variance test and a logistic regression show that self-pollen tubes grow at a significantly slower rate than outcross tubes. These observations suggest that there could be a complex system of self-incompatibility in P. leucophaea.

Using prescribed fire as a tool in restoration: Surprising results between seasons and guilds. S. Windhager* and M.T. Simmons. Lady Bird Johnson Wildflower Center, 4801 La Crosse Avenue, Austin, TX 78739. (512) 292-4200.

The last 150 years have seen significant changes to the savannas of the Texas Hill Country brought on primarily by fire suppression and overgrazing. As we begin to restore these environments, we must have a better understanding of the effects of the land management tools at our disposal, and how these affect community dynamics in all seasons. Prescribed fire in throughout the Midwest is commonly applied during dormant season, and few studies have documented the differences between various burn seasons. The Wildflower Center sought to test this by applying four treatments (n=6) of prescribed fire (winter, summer, fall and no fire) over 24 randomly selected plots (approximately 0.75 ha each) for two consecutive years. We sought to test the assumptions surrounding floristic guild response to seasonal application of prescribed fire, with the assumption that disturbance occurring while the guild was dormant would be most likely to benefit the species within this guild. Results, however, have shown that responses of species within guilds are far from uniform, often exhibiting no response or contra-indicated responses. While guild responses to fire season were not predictable, overall community structure and productivity were significantly influence by burn season. This study suggests that burn season radically effects community structure and that guild alone -- at least at the specificity at which they are commonly applied -- are not good predictors of these responses. This understanding will be critical for designing restoration projects that are aimed at restoring ecosystems with a specific desired community composition.

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Support for this conference was provided by the following sources: The Janet Meaking Poor Research Symposium Endowment Fund of the Chicago Botanic Garden, Lincolnshire Garden Club, USDA Forest Service/Midewin National Tallgrass Prairie