Publications and Presentations
First presentations to the scientific community! — Iowa Academy of Science Meeting, April 2014.
Gave three presentations at Iowa Prairie Conference, July 2015.
Gave three presentations at Midwest – Great Lakes Chapter Meeting of Society for Ecological Restoration, March 2016. Abtracts and Titles of Presentations are below.
Gave one presentation at North American Congress on Conservation Biology, July 2016.
Gave presentation at Midwest – Great Lakes Chapter Meeting of Society for Ecological Restoration, April 2017. Abstract and Title of Presentation Below.
Gave presentation at Iowa Prairie Conference in July of 2017; presented with Lisa Schulte Moore of the STRIPS Project at Iowa State University.
Gave presentation at Midwest – Great Lakes Chapter Meeting of Society for Ecological Restoration, April 2018. Abstract and Title of Presentation Below.
TITLES AND ABSTRACTS FROM PRESENTATIONS
2016: Impact of early mowing on prairie reconstruction in drought conditions.
Benedict, Russ, Jordan Drake, Ashley Oblander, Jessica Riebkes, Sean Robbins and Abby Saladino.
As part of the Prairies For Agriculture Project, this work examined the importance of mowing in the first years of growth following planting in prairie reconstructions. Early mowing is commonly used and may reduce competition between prairie seedlings and weeds. Plots were seeded in fall 2011 or spring 2012 with either 16 or 64 species. Some were mowed during the first year of growth, some during the first two years of growth, and some were un-mowed. Drought conditions prevailed during the first two years of growth, likely impacting our results. To quantify establishment, we counted individual plants in one meter2 frames; here we discuss results from the fourth year of growth. Data were analyzed with t-tests, and 16 species plots were analyzed separately from 64 species plots as were fall and spring planted plots. The impact of mowing was weak and complex. The majority of comparisons for individual species in un-mowed versus mowed plots (86.2%) were not statistically significant. In fall-planted plots, only 8.4% of comparisons showed statistically significant differences, with these split among the three treatments. For broad measures of plot success in fall–planted plots (cover of native species, number of species, number of total individuals), un-mowed plots were significantly more successful than mowed plots for some measures while others showed non-significant differences. In spring-planted plots, only 9.0% of comparisons for individual species showed significant differences between mowed and un-mowed plots; in those plots with significant differences, mowing led to greater success. Broad measures of success in spring-planted plots showed few significant differences, but mowing led to greater success plots in some cases. Overall, our results are inconsistent with previous findings possibly as a result of drought conditions. These findings are important given that drought is expected to become more common in the future.
2016: Impact of season of planting on prairie reconstruction in drought conditions.
Gabrielle Wilson, Austin Boldt, Jordan Drake, Ashley Oblander, Jessica Riebkes, Sean Robbins, Abby Saladino, and Russ Benedict.
This work examined impact of season of planting on plant establishment. Plots were seeded in fall 2011 or spring 2012, with 16 or 64 species. Some plots were mowed during the first year of growth, some during the first two years of growth, and some were un-mowed. Drought conditions began in fall 2011 and persisted until late summer 2013, likely impacting our results. To quantify establishment, we counted plants in one meter2 frames. Data were analyzed with ANOVA with mowing treatment used as a covariate (GLM in Minitab); 16 species plots were analyzed separately from 64 species plots. Data from the fourth year after seeding is presented here. Fall-planted plots were more successful than spring-planted plots. When each species was analyzed individually and results from 16 species and 64 species plots were combined, 28 species comparisons between spring and fall plots showed statistically significant differences (p < 0.05), 6 were approaching significance (0.10 > p > 0.05), and 22 were not statistically significant. For the 34 species comparisons that were statistically significant or approaching significance, fall plots had more individuals per meter2 than spring plots in 32 species. Additionally, in both 16 and 64 species plots, fall planting led to significantly higher native cover, higher number of species, higher number of individuals (NS in 16 species plots), and lower non-native cover than spring plots. Whether better performance of fall plots was due to drought conditions is difficult to assess based on experimental design but that is a likely explanation. Given that droughts and other altered weather patterns are expected to increase in the Midwest with changing climate, planting prairie reconstructions in fall may be advisable.
2016: Winners and losers: plant establishment during prairie reconstruction in drought conditions.
Oblander, Ashley, Jordan Drake, Jessica Riebkes, Sean Robbins, Abby Saladino, and Russ Benedict.
This study quantified establishment of prairie plants during the first three years of reconstruction; the first two of these were in drought conditions. By comparing our results to other research, we identified species that usually are successful early in prairie restorations but did not establish well at our site. These plants, some of which are important in Tallgrass Prairies, include Big Bluestem (Andropogon gerardii), Canada Wildrye (Elymus canadensis), Yellow Coneflower (Ratibida pinnata), Stiff Goldenrod (Oligoneuron rigidum), Leadplant (Amorpha canescens), and white prairie clover (Dalea candida). Drought is one possible explanation for the low success of these species at our site. Additionally, several plants in our plots established better than expected, especially Sawtooth Sunflower (Helianthus grosseserratus), Blackeyed Susan (Rudbeckia hirta), White Sage (Artemisia ludoviciana), and False Sunflower (Heliopsis helianthoides), possibly because they are tolerant of dry conditions and benefitted from the lack of competitors. Additionally, some species have established well and now are spreading into adjacent plots, including Western Wheatgrass (Pascopyrum smithii), Black-eyed Susan, and Sawtooth Sunflower. In some plots, the success of Helianthus grosseserratus and Heliopsis helianthoides appears to be slowing the establishment of other species. This possibility needs further exploration.
2017: Plant Bullies: Assessing the Aggressiveness of Species Used in Prairie Reconstructions.
Alex Mandi, Zachary Moss, Evelyn Kammeyer, Katelyn Miner, Dane Salow, and Russ Benedict.
As part of a long-term project, we assessed aggressiveness of 64 species of plants seeded into our research plots, each measuring 9 X 9 meters and surrounded by a two meter-wide mowed buffer. We recorded presence / absence and estimated abundance of each species in 31 un-planted plots interspersed among seeded plots. Five species that we seeded, Black-eyed Susan (Rudbeckia hirta), False Sunflower (Heliopsis helianthoides), Partridge Pea (Chamaecrista fasciculata), Sawtooth Sunflower (Helianthus grosseserratus), and Tall Boneset (Eupatorium altissimum) were the most aggressive, appearing in at least 80% of un-planted plots. Additionally, Canada Goldenrod (Solidago canadensis/altissima) and Old-field Aster (Symphyotrichum pillosus), which we did not plant but are abundant in surrounding areas, were present in 97.5% of un-planted plots. We also conducted these same counts in six plots that were planted with five species of prairie grasses but no forbs, and the results were very similar. This knowledge can assist future prairie reconstructions by identifying which species are most likely to spread beyond areas where they are planted. But given the valuable functions performed by these species, they are important to include in reconstructions. Therefore, future work will address reducing the quantity of seed of these species in plantings and delaying their seeding for one or two years while other plants get established.
2018: Impact of Increasing Plant Richness on Pollinator Use in Tallgrass Prairie
Austin Chipps, Rachel Heatwole, Alex Mandi, Jack Sytsma, Evelyn Kammeyer, and Russ Benedict
Pollinators play an important role in the natural world, facilitating plant success. Our research plots located near Pella, Iowa, were seeded in fall 2011 and spring 2012 as part of a larger project examining impacts of increasing plant richness on ecosystem services. Bees were visually counted monthly in 2017 from May to September in plots of tallgrass prairie varying in plant richness to investigate the impact of plant richness on bulk numbers of pollinators. During our observations, insects were visually separated into categories: Bombus spp., Apis mellifera, “native bee,” etc. Observations of pollinator activity were made in plots of low, moderate, and high plant species richness as well as plots containing only smooth brome (Bromus inermis) or Indiangrass (Sorghastrum nutans). All plots were located in the same 5.7 hectare research site. Plots containing only grass seldom were used by pollinators. Comparing the three richness treatments, pollinator use varied by month and showed no consistent pattern. However, high richness plots did not support greater numbers of pollinators. All prairie treatments supported more pollinator activity than grass-only plots. An important limitation to our study is that the close proximity of all of our plots to each other may have increased use of low richness plants by pollinators.