Throughout the past semester, I have been interning in Dr. Stuarts lab, working with Echinacea angustifolia. I performed two experiments during my time there. One comparing the differences in growth for two pre-germination methods. For this experiment, I measured the hight of the plant on three separate dates in order to determine the plant success for five cohorts.

No analysis was performed on Cohorts 4 and 5 because there was no growth for any of these plants. All plants with a height of 0 at the last day of measurement were considered dead.

We performed an ANOVA using R to compare the mean heights of Cohorts 1 and 2 at each age at which they were measured. After performing analysis for Cohorts 1 and 2, we found that there was no significant difference in the heights of the plants germinated using the Blotter method than those plants germinated using the Agar method. These results were similar for each of the three ages at which the plants were measured: 14, 28, and 35.

In addition to the three measurements performed on each of the plants, I also chose a single day in which to measure all of the plants. On March 19, I measured each of the 418 plants. We performed an ANOVA analysis on the mean heights of living plants on this single day in order to see if there was a cohort effect on the measurements. We found that there was no difference in measurements of the plants among treatments, but that height does differ among cohorts 1 and 2, according to a linear model, which we had expected.

There is much more analysis which can be done with the data collected and which we hope to do in the future, including comparisons for rate of emergence, timing of emergence, and survival of individual plants.

This image shows a dish of achenes pre-germinated using the blotter method.

This image shows a dish of achenes pre-germinated using the agar method.

I will also be working on the analysis of my second experiment throughout the summer, involving the comparisons of plant growth and plant morphology for four crosses between Echinacea angustifolia and Echinacea pallida. So keep an eye out for updates!

Hello! My name is Gia and I am one of the undergrads interning at the lab this quarter. I recently applied to the undergrad research expo that is held at Northwestern every year in May to try and present my findings about ant communities as part of the broader Echinacea project. Below is the abstract/ summary of my project that I sent in for the application.

Gia Hallaman

Katherine Muller, Stuart Wagenius

Linking Prairie Ant Communities & Fire: The Effect of Fire on Ant Diversity in Prairie Remnants of Western Minnesota

Research within the field of conservation emphasizes the maintenance of diversity. The Echinacea project focuses on the diversity of several prairie remnants in Western Minnesota, specifically upon a native plant living within these remnants called Echinacea angustifolia. For my project, I joined this long term effort by delving into some of the complexities surrounding the diversities of these prairie ecosystems. I evaluated the diversity of ant communities, which interact with an aphid species that feed exclusively on this plant, in remnants affected differently by fire. Historically, the presence of fire in long grass prairies has been positively correlated with the quality of the prairie by maintaining the dominance of grasses over woody plants. Specifically, I test the hypothesis that the ant communities differ between burned and unburned areas of native prairie remnants in Minnesota.I identified approximately a thousand ants, using dichotomous keys collected in 24 pit fall traps at two different sites on two separate dates during summer 2012, in order to evaluate the community composition and diversity. Preliminary analyses indicate that the diversity between recently burned and non-burned remnants was highly unique, with a disproportionately higher morphospecies count at one remnant, and with several morphospecies of Myrmica and Formica appearing exclusively in one location. This study shows that even by studying small organisms within an ecosystem, a great deal can be discerned about the health and diversity of the overall area and adds to out knowledge of the importance of fir in maintaining quality prairies throughout the Midwest.