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In summer 2018, I harvested 80 seedheads from 12 remnant Echinacea populations (ALF, EELR, KJ, NWLF, GC, NGC, SGC, NNWLF, LC, RRX, NRRX, YOH) to study patterns of reproductive fitness. I sampled heads in two ways – (1) I randomly selected 20% of the individuals at each site (43 individuals) and (2) I randomly sampled up to 5 individuals from full factorial combinations of high, medium, and low spatial isolation and early, peak, and late flowering time (i.e., high spatial isolation/early flowering, high spatial isolation/peak flowering, etc.) across all sites (37 individuals).
In January 2019, I dissected seedheads that I collected from the NW sites (ALF, EELR, KJ, NWLF, GC, SGC, NGC, KJ, NNWLF). I extracted the achenes by row to observe temporal variation in seed set within heads. I x-rayed the achenes and assessed seed set in January.
 Xray images that show whether achenes contain embryos or not Start year: 1996
Location: Remnant prairies in central Minnesota
Overlaps with: Phenology in the Remnants, Gene Flow in Remnants
Products: Check back with the flog for preliminary results and annual reports.
You can read more about reproductive fitness in remnants, as well as links to prior flog entries mentioning the experiment, on the background page for this experiment.
In summer 2018, I began a project to look at pollen movement within and among the remnant populations. To do this, I chose two focal areas, the NW sites in the study area (populations: ALF, EELR, KJ, NWLF, GC, SGC, NGC, KJ, NNWLF) and the SW sites (populations: LC, NRRX, RRX, YOH, and two large populations in between these sites). I mapped and collected leaf tissue from all individuals in the study areas and harvested seedheads from a subset of these individuals (see Reproductive Fitness in Remnants). I am currently extracting the DNA from the leaf tissue samples and a subset of the seeds I collected, and will use the microsatellite markers that Jennifer Ison developed in her dissertation to match up the genotypes of the offspring (i.e., the seeds) with their most likely father (i.e., the pollen source).
 An Echinacea that has had today’s load of pollen fully removed by pollinators Start year: 2018
Location: Remnant prairies in central Minnesota
Overlaps with: Reproductive Fitness in Remnants, Phenology in the Remnants
Products: Check back with the flog for preliminary results and annual reports.
Team members who worked on this project include: Amy Waananen
In 2018, we checked 80* focal plants at 12 remnants for nearby seedlings found in previous years. We found 97 out of the original 955 seedlings (26 fewer than the 123 found last summer). Although challenging to obtain, information about the early stages of E. angustifolia in remnants is critical to understanding the demography of these remnant populations. With still no flowering plants, it is plain to see how long it takes for Echinacea to begin flowering.
Between the summers of 2007 and 2013, team Echinacea observed the recruitment of Echinacea angustifolia seedlings around focal plants at 13 different prairie remnants. The locations of these seedlings were mapped relative to each focal plant and the seedlings (now former seedlings) are revisited each year. For each of these former seedlings, we make a record each year updating its status (e.g., basal, not found), rosette count, and leaf lengths. We also try to update the maps, which are kept on paper and passed down through the years, each person using a different color ink. As you can imagine, they are quite colorful & marked up by now.
 It can be tough to find small plants like this one! Year started: 2007
Location: East Elk Lake Road, East Riley, East of Town Hall, KJ’s, Loeffler’s Corner, Landfill, Nessman, Riley, Steven’s Approach, South of Golf Course remnants and Staffanson Prairie Preserve.
Overlaps with: Demographic census in remnants
Data collected:
- Electronic records of status, leaf measurements, rosette count, and 12-cm neighbors for each seedling. Currently in Pendragon database
- Updated paper maps with status of searched-for plants and helpful landmarks
Products: Amy Dykstra used seedling survival data from 2010 and 2011 to model population growth rates as a part of her dissertation.
You can read more about the seedling establishment experiment and links to previous flog entries about the experiment on the background page for this experiment.
* This number originally read 119, which is incorrect according to the sling master datasheet from 2018. EE edited this on 8 Jan 2020 while writing the PSR for 2019. I encourage someone to correct this number if it is now incorrect but to the best of my knowledge 80 is the number of maternal plants/circles visited.
In summer 2018, we searched experimental plot 7 for Echinacea plants that are crosses between and within E. angustifolia and E. pallida. Of the 294 plants originally planted, we found 169. However, for the first time in the history of experimental plot 7, we found a flowering plant (an E. pallida x pallida cross)! The table below shows the counts of Echinacea plant in the summer of 2018. In addition to the lowest survivorship, the native E. angustifolia also has been the smallest (above-ground) over the five experimental years. Uh oh!
 Riley with the first ever flowering head in exPt7!
| Status 2018 |
ang x ang |
ang x pal |
pal x ang |
pal x pal |
| not found |
52 |
12 |
26 |
35 |
| found |
22 |
16 |
59 |
72 |
Start year: Crossing in 2012, Planting in 2013
Location: Hegg Lake Wildlife Management Area – Experimental Plot 7
Overlaps with: Echinacea hybrids: exPt6; Echinacea hybrids: exPt9
Data collected: Rosette number, leaf number, length of longest leaf, herbivory for each plant collected electronically and exported to CGData. Recheck information for plants not found was also collected electronically and stored in CGData. In 2018, Riley also used a Li-Cor 6400 to analyze ecophysiological traits of Echinacea in expt7. This included photosynthetic rate and water use efficiency. Riley has this data and we’ll make it available after he’s done with his thesis.
Products: Riley’s 2018-19 Biology Honors Project at Gustavus. Riley found that within-species Echinacea angustifolia crosses have lower survivorship, above-ground biomass, and ecophysiological traits than other cross types. Riley made a poster, is writing his thesis, and will defend it in May.
You can read more about rexPt7, as well as links to prior flog entries mentioning the experiment, on the background page for this experiment.
West Central Area School District and grounds are located in west central Minnesota. The high school is located in Barrett, MN which encompasses five small communities (Barrett, Hoffman, Kensington, Elbow Lake, and Wendell) that have united to make one high school. The school was built in 1994 and we are still in the process of restoring our 35 acres of land (Environmental Learning Center – ELC) into native prairie plant species. The ELC has several trails, an observation deck, and a pier that reaches into a small pond. The area has recently begun to be more and more incorporated into several classroom activities. One of the science classes used the ELC in 2018 to sample types of Bombus (bumblebee) species and populations, the agricultural instructor has been using the ELC for soil sampling and classification along with looking at soil profiles. Even the art teacher has had drawing sessions from the observation deck and the English teacher used it for writing exercises. The plan is to utilize the ELC more and more in upcoming years and we have received outstanding support from the school administration, school board, and local businesses in promoting this part of our school. Plans for 2019 are to have 12 plots that 8m x 12m in which four are burned in the spring, 4 are burned in the fall and 4 are not burned at all. As years progress, we plan to have classes engaged in monitoring the progression and health of some native species in these plots, especially Echinacea angustifolia, which will be hand planted in the plots in May of 2019.
Start year: 2019
Location: West Central Area High School
Overlaps with: Nothing… yet!
GPS points shot: 96 points delineating the future plot locations
 The location of the field site, near the high school
Hello flog, one last time!
Today marks the end of my three weeks here on Team Echinacea, and I’m certainly sad to say goodbye! Nevertheless, it was exciting and rewarding to culminate this externship with a week of data analysis, poster creation, and presentation of findings to the team. While Tris chose to analyze data from Michael’s Echinacea pollen limitation experiment, Julie and I decided to delve into the worlds of Liatris aspera and Solidago speciosa, two other Asteraceae common to prairie ecosystems. Lea has been working with these species for her PhD project over the past few years, studying how timing and location of flowering influences reproductive success, so she was a great help as we commenced our analysis!
After having meticulously cleaned, counted, and classified innumerable Solidago and Liatris flowering heads, Julie and I wondered how the vast differences in head count between these two species may impact each plant’s fecundity (when Liatris plants generally have 10-20 heads, and many Solidago plants have hundreds or even thousands) . Further, knowing that human populations have largely suppressed the occurrence of natural fires in today’s prairies, we were also interested in analyzing the effects of prescribed burns on these common prairie species. We put these two questions together in our data analysis by forming a statistical interaction model–one in which the effect of fire would interact with the effect of flowering head count to influence reproductive success–and fitting it to our Liatris and Solidago data. Interestingly, we did not uncover the same results for these two closely-related plants! For Liatris, the interaction model was highly supported by our data: the head count of plants seemed to have more effect on seed set (a measure of fecundity) in plants that had not been recently burned than in plants that had been recently burned. Yet, for Solidago, this pattern was not present. Our findings suggest that prairie management strategies, of which prescribed burns are an integral part, should carefully consider the species composition of a prairie before burning, because different species may react to burn treatment in different ways. Check out our poster, attached here, for a more detailed analysis, as well as plots of our models!
Before I sign off, I want to send a huge ‘thank you’ to every member of Team Echinacea! This opportunity was incredibly influential for me–this was my first real research experience, and I learned so much about ecology, networking, career paths, data collection, statistics, and more. I had an amazing time, and I hope to see some team members again someday!
Thank you again,
Sarah
PDF version below:
Soliatris2018 Poster
Hi flog,
Wow! These last three weeks passed by super quickly! While the first two weeks were focused on seed cleaning, seed counting, and x-raying, we spent this past week on our independent projects. But that’s not to say this week was easy! In the past 5 days, I wrote exactly 900 lines of code in R to generate the figures and perform the analyses.
To get at how current pollen limitation affects Echinacea growth and future fitness, I performed analyses testing differences in plant traits between pollen exclusion, pollen addition, and open pollination treatments. I did not find evidence that pollination treatment affected either growth or fitness, which indicates that current pollen limitation will not benefit Echinacea in the future. This could be because Echinacea is not resource limited or because the cost of seed production is negligible.
Many thanks to the members of Team Echinacea who helped guide me through this process and made working in the lab such a pleasure!
Tris
Link to Poster
The aphids were a hit at Carleton’s Summer Research Symposium. At the Carleton College Summer Research Symposium on October 26th, I presented a poster on my work on the aphid addition/exclusion experiment. Over the summer, I administered the aphid addition and exclusion treatments for the experiment and collected data on leaf senescence and herbivory on plants in the study. Since August, I have been developing an aster model in R to analyze differences in fitness between these two experimental groups. Preparing the aster model for my project was quite a bit of work, but I learned more about R, statistical analysis, and plant-herbivore interactions in the process. Interestingly, Aphis echinaceae has not had an impact on plant fitness over the 8 years of the study.
I am excited to see how the experiment progresses in the coming years, and how the addition of data on seed set affects the results of future fitness models. Quite a few visitors to the symposium were also interested in the results of my analysis and my experience working with the aphids. It was a pleasure to represent the Echinacea Project at Carleton and to have a chance to share the fantastic work the team did over the summer.
Hello Echinacea folks! After a great summer at the Echinacea Project, I returned to Gustavus to work on the morphological and physiological data I collected at experimental plot 7. In my time at Gustavus so far, I wrote a proposal for my project so I can analyze my data and undertake a senior honors project under familiar Echinacea advisors Pamela Kittelson, Stuart Wagenius, and Sanjive Qazi. I have also worked on a methods section for my final honors paper and made a poster (attached below). In addition to my project, this fall I have been working on a project to implement composting and sustainable practices in Saint Peter restaurants and a project analyzing microRNA-mediated stress response in smooth cordgrass. The next steps for my honors project are to write up an introduction and do statistical analysis over our January-term. I will be performing aster and cluster analyses and am really excited to get back into some R coding! echinaceaPoster1_Thoen
This morning the much-diminished Team Echinacea (Stuart, Kristen, Lea, Michael, and I) gathered at the Hjelm house to start the day. Lea went to Staffenson Prairie Preserve to measure the flowering phenology of Liatris and Solidago plants. Michael and Kristen began to prepare experimental plot 8 for management in the coming year. The team will treat rogue Ashe trees and collect and broadcast the seeds of several prairie plant species in this plot. This is part of an ongoing effort to ensure that the plant community within the plot is consistent throughout.
Meanwhile, I assessed the leaf damage and senescence of plants in the aphid addition/exclusion experiment in p1. This was the final component of the fieldwork involved in this experiment for the season, and the last step in my independent project before I begin statistical analysis. The next step is to gauge fitness differences between plants in the aphid addition and exclusion treatments by constructing an aster model. While it was exciting to finish this aspect of the project, I will miss spending time with my Aphis echinaceae friends.
Over lunch the team prepared for inclement weather by sharing our experiences of intense weather events. After that, Kristen presented an update on her master’s project. She shared some intriguing preliminary results about the nesting preferences of native ground-nesting bees. We are all looking forward to the results of her study! Due to the rainy weather, the team was ready to call it a day after Kristen’s presentation. We held a short meeting to plan next week’s schedule and then headed home for the weekend.
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