In summer 2021 and summer 2022, we investigated fire effects on Liatris aspera across 30 patches of remnant prairie in Solem Township, MN. We did not collect any new Liatris data in 2023. All harvested samples were processed in the lab during spring 2023. All data has been curated and are analysis-ready.
Had to go back to 2021 to get a Liatris photo, good riddance!
Start year: 2021-2022
Location: 30 patches of remnant prairie in and around Solem Township, MN
Data collected: Spatial location, reproductive effort, and reproductive outcomes data have been curated in the remLa repo. All data are analysis ready.
Samples or specimens collected: All harvested reproductive material have been processed in the lab. Half of the collected seed was sowed in the recently burned southeast hill at the farm. The other half have been reserved for sowing in P2 (provided it burns in spring 2024).
Products: Jared has conducted preliminary analyses. Stay tuned in 2024 for more info!
You can read more about the Liatris fire and flowering experiment, as well as links to prior flog entries about this experiment, on the background page for this experiment.
Since 1995, the Echinacea Project has been mapping and collecting demographic information on Echinacea angustifolia to generate long-term records detailing individual fitness in prairie remnants. In summer 2023, Team Echinacea visited 42 prairie remnants to search at 2443 locations where adult Echinacea plants had been previously mapped. We call this “total demo.” At small sites, the team took records for all adult plants found at a site (no change in total demo protocol from previous years). At larger sites, we scaled down and visited a subset of adult plants. Burning led to high flowering rates and lots of newly flowering plants entering the census, which stressed our system for total demo. This year we did not visit plants that were “not present” for the past 3+ years and we also capped total demo points at 100 per site. For example, at Landfill, we searched at 100 locations at Landfill East and 100 Locations at Landfill West.
We used stake files on our high-precision GPS units to stake to each Echinacea plant in our total demo visit list, where we recorded flowering status, number of flowering heads, number of rosettes, and near neighbors of the plant on handheld data collectors (visors).
In addition to total demo, we searched and took records for all flowering plants in our remnant sites. For flowering demo, we visited 50 sites. In summer 2023, we took 5,601 demographic records in prairie remnants (demo) and 1929 GPS records (surv). We saw a much lower flowering year following 2022, with ~1586 flowering plants total. At Landfill, there were ~262 flowering plants and at Loeffler’s corner, there were 285.
Alexa and Jak step carefully through Kjs as they search for flowering Echinacea plants. 63 plants flowered at Kjs in 2023!
We also took demo and surv data as part of our Pollen and Nectar project where we will compare characteristics of pollen and nectar in burned vs. unburned prairies. We collected demographic data at a subset of plants at several sites where we have never done demo or surv. We put out our first tags at hulze, hulzw, torges, torgen, hutche, hutchw, and koons.
This year, we put out 528 new tags which started at 28001. Two 29000 tags were accidentally created and placed in Landfill East, but those were quickly removed during our demo rechecks following completion of flowering demo and total demo.
Lindsey visits an 18 headed Echinacea plant at Steven’s Approach. This plant produced the most heads of any this year.
After revisiting a final round of recheck plants during a trip to Minnesota in mid-November, we are just getting ready to move data from aiisummer2023 into demap.
Start year: 1995
Location: Remnant prairie populations of the purple coneflower, Echinacea angustifolia, in Douglas County, MN. Sites are located between roadsides and fields, in railroad margins, on private land, and in protected natural areas.
Total demo: Bill Thom’s Gate, Common Garden, Dog, East of Town Hall, Golf Course, Martinson’s Approach, Near Pallida, Nessman, North of Golf Course, South of Golf Course, Sign, Town Hall, Tower, Transplant Plot, West of Aanenson, Woody’s, Yellow Orchid Hill, plus the recruitment plots REL, RHE, RHP, RHS, RHX, RKE, RKW
Annual sample: Aanenson, Around Landfill, East Elk Lake Road, East Riley, KJ’s, Krusemarks, Loeffler’s Corner, Landfill, North of Railroad Crossing, Northwest of Landfill and North of Northwest of Landfill (lumped), On 27, Riley, Railroad Crossing, Steven’s Approach, Staffanson Prairie
Plant status (can’t find, basal, dead this year’s leaves, dead last year’s leaves, flowering), number of rosettes, nearest neighbors, and head count, if flowering
All GPS files are found here: Dropbox/geospatialDataBackup2023
All demo and surv records are stored in the aiisummer2023 repo
The most recent copies of allDemoDemo.RData and allSurv.RData can be accessed at Dropbox/demapSupplements/demapInputFiles
Samples or specimens collected: NA
Products:
Amy Dykstra’s dissertation included matrix projection modeling using demographic data
The “demap” project is a long-term dataset that combines phenological, spatial and demographic data for remnant plants
You can read more about the demographic census in the remnants, as well as links to prior flog entries about this experiment, on the background page for this experiment.
I’ve had an amazing semester here in the Echinacea Lab, and today I presented my final update on my internship project. I was able to receive feedback on how to improve both my project and presentation skills. One of the suggestions I received was to add more background to my presentation, so here is some supplemental information to go along with the PowerPoint (attached below). I was working with the P01-nat batch for two consecutive years, 2021 and 2022. I was looking at the plant health indicators of number of basal leaves and length of the longest basal leaf from 2021 because plants receive energy through photosynthesis. My though process was that leaves that are longer and more abundant would lead to a greater ability of an individual plant to photosynthesize and therefore invest more energy in reproduction. I was looking at the reproductive effort and success in the following year, 2022, since Echinacea angustifolia are long-lived perennials. The individual plants that I was working with were originally planted in 1996, so they were pretty well established in the study sites in Minnesota.
I also received feedback on my experimental design, including changing my experimental design a little bit. My current study is phrased as causally linked factors but is more in line with exploring an association between basal leaves and reproductive effort and success rather than a causation. In order to explore more of a causal relationship, one of the suggested studies was to clip leaves so that there was a randomized manipulation on the plants instead of an observational study. Limiting the basal leaves of random plants could allow for a stronger causal relationship to be established between the two factors. A second suggestion to strengthen my current study was to include data from multiple years, since Echinacea angustifolia are long lived and potentially have certain years where reproductive effort spikes over their life cycle and doesn’t spike again, as is one of the potential implications in Sophia’s pollen limitation study.
My hypotheses were not supported by my data, but they still have implications for the further potential future study I mentioned above. The data I collected did not support my hypothesis because the p-values were too high, meaning the data was not statistically significant. I received a suggestion that I should investigate one plant seen in the total achene count graphs (slide 6 of my presentation) that had no basal leaves but produced 200 achenes in the following year. It is possible that this individual only had cauline leaves in 2021, in which case it wouldn’t be relevant to a correlation between basal leaves and reproductive output. Two directions for additional studies that I suggested were the relationship between plant height and reproductive output and overall reproductive fitness as it relates to the number of heads on a plant. The latter question is one that I was going to explore, but I chose to combine the data for my study so that each data point represented the plant as a whole.
I am really grateful to have had the opportunity to be a part of the Echinacea lab this fall. I learned a lot about working in a lab and data analysis using R. I want to give special thanks to Wyatt, Stuart, and Sophia for helping me with R and my project overall, and to all the volunteers and student workers who helped me count, classify, and randomize the 2022 P01-nat data.
This week I worked on randomizing and counting. Thanks to the help of the student workers and volunteers, there is only about a quarter of the P01-nat batch left to randomize. I am hopeful that I will be able to complete the randomizing by the end of next Tuesday.
Today I spent my day counting achenes from the scans that I completed earlier this month. The counting process takes place on the ACE website. Each individual scan requires three different people to count it, and then the average of those three counts is taken as the most accurate one. I am completing one of the three counts for the entire batch. The ACE website is very user friendly and straight forward. The images are counted in a random order to keep the process as accurate as possible. To begin counting, I click the “count achenes” button on the dashboard (Right of Image 1). The first thing I do for every new scan is to confirm that the file name matches the envelope displayed in the scan (Image 2). After I confirm the file name and letno, I click on each achene and a blue dot is overlayed on the image (On the right of Image 2). The software keeps track of how many achenes I have counted in the image. Once I have double checked that I have accounted for every achene, I click “submit count”. The website goes back to the dashboard, and I begin the process over again. As of the end of the day today, I am 55.68% done with counting P01-nat (On the bottom of Image 1). Many thanks to the volunteers for helping me reach this point!
Image 1. ACE dashboard Image 2. A scan after all achenes have been counted.
For my research project, the Echinacea heads in batch P01-nat have to go through the processes of cleaning, rechecking, scanning, counting, randomizing, x-raying and finally classifying before I can analyze the data. In my last blog post I detailed the methods of randomizing, and in this one I will be describing the processes of cleaning, rechecking, and scanning, the latter two steps which I have been working on in the past couple of weeks for P01-nat.
Cleaning and rechecking are very similar processes. During the cleaning process, I gently crush the Echinacea head against a Pyrex dish to separate the achenes from the head, and I use forceps to carefully remove the achenes that don’t fall out on their own. Once all of the achenes are removed from the receptacle, I put the chaff in one envelope and achenes in another and label each envelope with my initials, the date, the twist tie color, and the contents of the envelope. I put the twist tie, empty receptacle, and the two coin envelopes in the small brown paper bag. I initial and date the data sheet next to the proper letno. The rechecking process is done to check for achenes that might have been missed during the initial cleaning. For this step, only the chaff, receptacle, and twist tie are looked at again by a second person. At the end of rechecking, letno stickers are placed on the coin envelopes and the coin envelopes are then placed in numerical order in cereal boxes in preparation for scanning (Fig. 1). The same information that was recorded in the data sheet for the cleaning is recorded again under a new column for rechecking. Stay tuned, photographs of this process will be added next week!
The method for scanning the achenes is straight forward. The scanning setup is pictured below (Fig. 1 and 2). I scan each envelope of achenes one at a time by scattering the achenes evenly on a glass bottomed scanning tray, which is placed directly on the scanner. I place the coin envelope, letno label down, underneath the scanning tray and make sure that no achenes are behind it. Each scan is done at 400dpi, and saved to the server in the P01-nat folder under the same file name as the letno in the format “N-number-letter”. Once all of the achenes in each set are scanned, they are moved to the randomizing tray, which is a process I detailed in my last post. The digital files will be uploaded to the ACE website for counting once all of P01-nat has been scanned, which could be as early as next week!
Fig. 1 – Coin envelopes of achenes scanned and waiting to be scanned. Fig. 2 – Scanning setup.
It’s autumn at Chicago Botanic Garden! Geese fly south overhead, the trees are ablaze, goldenrod has gone to seed, and there was even a dusting of snow on the ground this morning (which made for a treacherous bike ride along the Green Bay Trail).
But there are also many other signs within the Population Biology lab that will tell you fall is in the air. All of our heads from 2023 are done drying and we have just begun to inventory our harvest.
Here is Wyatt, pulling out the very first bag for 2023 inventory.
How else do we know it’s fall? We are gathering seeds and datasheets in preparation for a final return to Minnesota. We put these seeds out in experimental plots/transects or remnants “as late as possible, but not to late”. Ian is entering the last of the data from pollen and nectar collection this summer and it feels like forever ago. And when 4pm hits, the sun shines though the atrium and fills our lab with natural light. This doesn’t happen very often, but it’s a treat when it does.
Maybe it is all these tell-tale signs from the Echinacea Project that told the wild geese- “It was time to go”.
Many plants, including Echinacea angustifolia, flower vigorously during the summer after a prescribed burn. We’ve demonstrated that the benefits of fire for seed production, in many circumstances, are bigger than just the increase in flowering. The additional boost to seed production results from better pollination after fires compared to other times. Now we are trying to figure out what’s going on with pollination–why is it better after a fire? It might be related to pollen or nectar, which are foods for the bees that pollinate Echinacea. Here are two possibilities: 1) after a fire, plants produce more or better pollen or nectar which draws in bees from farther away, so the plants get more visits and better pollination, presumably the bees are happier with abundant & healthy food. 2) after a fire, plants produce less or lower quality pollen or nectar which means bees need to fly to more plants to get a decent meal, so the plants get more visits, and the bees are probably frustrated with skimpier meals and bad food. The third possibility is that plants produce the same quality and quantity of pollen & nectar regardless of fires.
Over the summer we systematically collected pollen and nectar from many Echinacea plants in many populations (19) over many days. Our goal is to evaluate how fires affects the quality and quantity of pollen & nectar produced by Echinacea plants. We are getting close to wrapping up data-entry for our field collection of pollen and nectar from Echinacea angustifolia. Here’s a summary of data-entry progress so far…
Each “tagCt” is the number of Echinacea plants we sampled at each site. We will keep you posted!
Funding for this project was provided by the Minnesota Environment and Natural Resources Trust Fund as recommended by the Legislative-Citizen Commission on Minnesota Resources (LCCMR).
I start the process of randomizing with the coin envelopes of re-checked achenes. The first part of the process is spreading the achenes out evenly across a circle that is sectioned off into 11 parts, each identified with a letter. Using a random letter generator, I select two sections of achenes. I put the rest of the achenes back into their original coin envelope. I sort and count the achenes that were selected by the random number generator into two groups, informative and uninformative. Achenes are uninformative if they are broken, underdeveloped, predated or ray achenes because these types of achenes are either known to be sterile or the seed could have fallen out during the cleaning process. I then put a label with identification information on both a white coin envelope and a clear plastic baggie. On the white envelope, I write the number of informative and uninformative achenes as well as my initials and the date. I put the uninformative achenes in this envelope and the informative achenes in the clear plastic baggie to be x-rayed. I record the data for the number of uninformative and informative achenes in the 2022 randomizing data sheets and put the coin envelopes back in their original box and the randomized ones in a new box so that they can be prepared for x-raying. This week I switched from the bbMost 2022 batch to a smaller batch that will be more manageable to complete during the remainder of my semester long internship with the Echinacea Project. I will be carrying out the randomization using this method after the rechecking and scanning of the new batch is completed.
Here in the lab at the Garden I’ve settled, In demap and on ACE, oh boy, have I meddled. New faces I’ve seen, Not to mention achenes And all through the trails I have pedaled.
The foliage here is quite a delight, And from the Metra the city looks bright. But Minnesota’s fire Is my heart’s true desire, The prescription to better my plight.
