2022 Update: Dykstra’s local adaptation experiment

This experiment was designed to quantify how well Echinacea angustifolia populations are adapted to their local environments. In 2008, Amy Dykstra collected achenes from Echinacea populations in western South Dakota, central South Dakota, and Minnesota and then sowed seeds from all three sources into experimental plots near each collection site. Each year, Team Echinacea takes a demographic census at the western South Dakota and Minnesota plots; we abandoned the central South Dakota plot after it was inadvertently sprayed in 2009, killing all the Echinacea.

In 2022, during the annual census of the experimental plots, we found 135 living Echinacea plants, including 102 basal plants and 33 flowering plants. All but two of the flowering plants were in the South Dakota plot. A wetter-than-average spring may have contributed to the flowering output of these plants. The South Dakota prairies were as green as Amy can remember seeing.

Pictured is one of the flowering plants in the South Dakota plot. We performed the census on June 30, before the flowering heads started dehiscing pollen.
  • Start year: 2008
  • Location: Grand River National Grassland (Western South Dakota), Samuel H. Ordway Prairie (Central South Dakota), Staffanson Prairie Preserve (West Central Minnesota), and Hegg Lake WMA (West Central Minnesota).
  • Overlaps with: Dykstra’s interpopulation crosses
  • Data collected: Plant fitness measurements (plant status, number of rosettes, number of leaves, and length of longest leaf)
  • Samples collected: Heads from all flowering plants; Amy stores the heads in her office at Bethel University.
  • Products: Dykstra, A. B. 2013. Seedling recruitment in fragmented populations of Echinacea angustifolia. Ph.D. Dissertation. University of Minnesota. PDF

You can read more about Dykstra’s local adaptation experiment and see a map of the seed source sites on the background page for this experiment.

2022 Update: Dykstra’s interpopulation crosses

Small remnant Echinacea populations may suffer from inbreeding depression. To assess whether gene flow (in the form of pollen) from another population could “rescue” these populations from inbreeding depression, we hand-pollinated Echinacea from six different prairie remnants with pollen from a large prairie remnant (Staffanson Prairie) and from a relatively small population (Northwest Landfill) in 2008. We also performed within-population crosses as a control. Amy Dykstra (with help from Caroline Ridley) planted the achenes (seeds) that resulted from these crosses in an experimental plot at Hegg Lake WMA.

We sowed a total of 15,491 achenes in 2008. 449 of these achenes germinated and emerged as seedlings. Each summer, we census the surviving plants and measure them.

In 2022, we found 26 surviving plants; all were basal. Joey McGarry staked the plant locations, Amy Dykstra searched for the plants, and Brad Dykstra recorded the data.

  • Start year: 2008
  • Location: Hegg Lake WMA
  • Overlaps with: Dykstra’s local adaptation
  • Data collected: Plant fitness measurements (plant status, number of rosettes, number of leaves, and length of longest leaf), and notes about herbivory. Contact Amy Dykstra to access this data.
  • Samples collected: NA
  • Products: Dykstra, A. B. 2013. Seedling recruitment in fragmented populations of Echinacea angustifolia. Ph.D. Dissertation. University of Minnesota. PDF

You can read more about Dykstra’s interpopulation crosses, as well as links to prior flog entries mentioning the experiment, on the background page for this experiment.

What did we do in summer 2022?

Team Echinacea was busy this summer! Over the last few weeks, we have been posting updates on projects from summer 2022. Here is the complete list.

Experiments with 2022 updates:

2022 Update: Aphid addition and exclusion

In summer 2022, Team Echinacea continued the aphid addition and exclusion experiment started in 2011 by Katherine Muller. The original experiment included 100 plants selected from exPt01 which were each assigned to have aphids either added or excluded through multiple years. The intention is to assess the impact of the specialist herbivore Aphis echinaceae on Echinacea fitness.

In 2022, Emma Reineke and Kennedy Porter conducted the aphid addition and exclusion project. They located 24 living exclusion plants and 17 living addition plants. Similar to the past two years, they did not find any aphids in exPt01, so they started to introduce a new population of Aphid echinaeceae into ExPt1. Learn more in the summer aphid update.

  • Start year: 2011
  • Location: Experimental Plot 1
  • Overlaps with: Phenology and fitness in P1
  • Data collected: 
    • Plant status (basal, flowering, not present), aphids present, ants present, herbivory (number of leaves significantly chewed on), and the number of aphids added/removed (depending on specific treatment)
    • Protocols and datasheets are located at ~Dropbox\aphidAddEx\aphids2022
  • Samples collected: NA
  • Products:
    • Andy Hoyt’s poster presented at the Fall 2018 Research Symposium at Carleton College
    • 2016 paper by Katherine Muller and Stuart on aphids and foliar herbivory damage on Echinacea
    • 2015 paper by Ruth Shaw and Stuart on fitness and demographic consequences of aphid loads

You can read more about the aphid addition and exclusion experiment, as well as links to prior flog entries mentioning the experiment, on the background page for this experiment.

2022 Update: Dust experiment

In summer 2021, Team Dust began a project to look at the effect of dust on reproduction of Echinacea. They randomly assigned treatments of ‘dust’ or ‘no dust’ to 41 heads in ExPt2. Many heads were eaten by ground squirrels, but they harvested the 18 survivors, and Amy Waananen x-rayed the achenes from these heads in March 2022 to evaluate seed set.

This summer, Emma Reineke took the lead on the project, assisted by Kennedy Porter. They applied dust treatments to 64 Echinacea heads at a prairie remnant, Nice Island. They also conducted an observational study using dust traps to measure dust levels at varying distances from unpaved roads. Learn more in Team Dust’s summer update. In late summer, the team harvested the 64 heads, and Amy now has them at UMN. Emma recently received UROP (undergraduate research opportunities program) funding to continue research on the dust project during spring semester.

  • Start year: 2021
  • Location: ExPt2 and Nice Island
  • Overlaps with: None
  • Data collected:
    • Relative amounts of dust levels along unpaved roads at Aanenson and Riley
    • Datasheets are located at ~Dropbox\teamEchinacea2022\emmaReineke\Dust 2022
  • Samples or specimens collected:
    • We collected 64 heads, which are currently in the R. Shaw Lab in the Ecology building at UMN.
    • The dust traps and dusty styles are also at UMN.
  • Products: Amy presented Team Dust’s work at The Prairie Enthusiasts (TPE) conference in February 2022.

You can read past flog entries about the dust experiment here.

2022 Update: Demographic census in remnants

Since 1995, the Echinacea Project has been mapping and collecting demographic information on Echinacea angustifolia to generate detailed, long-term records of individual fitness in prairie remnants. In summer 2022, Team Echinacea visited 34 prairie remnants to search at 2927 locations where adult Echinacea plants had been previously mapped, a process we call “total demo.” At small sites, the team searched for all adult plants, and at large sites, we visited a subset of the adult plants. This year, we did not visit plants that had been “not present” for the past 4 years. However, we added plants that flowered for the first time in 2019, 2020, or 2021. At the large sites, we added many more plants than we removed; at Landfill, we removed 18 plants but added 129 new plants, so we visited 285 plants in total. We plan to revisit the total demo protocol before next summer so our subsets do not reach unreasonable sizes.

At each Echinacea plant, the team used handheld data collectors (visors) to record the flowering status, number of flowering heads, number of rosettes, and near neighbors of the plant. We then mapped the location of every flowering plant within each prairie remnant using a high-precision GPS unit. Unfortunately, the new GPS unit, Collins, stopped working early in the summer. Nevertheless, the team persisted with the old GPS.

Johanna and Kennedy collect demographic data on Echinacea at On27

In summer 2022, Team Echinacea collected 7926 demographic records (demo) and recorded 3708 GPS points (surv). In total, we collected data on ~2870 flowering Echinacea angustifolia plants. A combination of favorable weather and prescribed burns made it a record-breaking year for flowering Echinacea. Landfill had 713 flowering plants this year (east: 373, west: 340) compared to only 327 last year. There were 518 flowering plants at Loeffler’s Corner (east: 292, west: 226), and 266 flowering plants at Staffanson. The demo and surv datasets are in the process of being combined with previous years’ records of flowering plants in “demap,” the spatial dataset of remnant reproductive fitness that the Echinacea Project maintains.

This year, new tags ranged from 27001 to 27999. However, due to the high number of flowering plants and issues with people adding unnecessary tags, we ran out of tag numbers in the 27000s. Therefore, we also used new tags ranging from 25651 to 25890 and from 26881 to 26999 in 2022.

We are especially interested in understanding how fire influences reproductive effort in fragmented prairies. The following sites were burned in spring 2022: Bill Thom’s Gate, Landfill West, Loeffler’s Corner West, Martinson’s Approach, Northwest of Landfill, North of Northwest Landfill, Staffanson West, and West of Aanenson. We noticed increases in flowering at most burned sites, even some of the small ones. For example, West of Aanenson had 7 flowering plants this year, which is the highest flowering rate on record since we started mapping Echinacea there in 1999. Stay tuned for more results from this intriguing dataset!

Members of Team Echinacea do total demo at the Transplant Plot
  • 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, Randt, 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
  • Overlaps with: Flowering phenology in remnantsreproductive fitness in remnantsEA fire and fitnessfire and flowering at SPP
  • Data collected:
    • 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/geospatialDataBackup2022
    • All demo and surv records are stored in the aiisummer2022 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.

2022 Update: Fire in recruitment experiment

This recruitment experiment was originally established in 2000 to quantify seedling emergence and juvenile survival of Echinacea angustifolia during its reintroduction to sites with varying land-use history and burn schedules. Before 2014, we collected detailed data on each plant in the plots. Since 2014, Team Echinacea has censused each plot yearly to collect demographic data for every flowering plant.

In 2022, Team Echinacea visited 9 recruitment plots and searched for 168 Echinacea angustifolia plants that had flowered previously. Across the 9 plots, we found 76 basal plants and 126 flowering plants, and we were unable to find 14 plants. Of the flowering plants, 35 plants flowered for the first time in 2022. It was a high flowering year! For each flowering plant, the team collected demographic data (number of rosettes and flowering heads) and shot a GPS point at the exact location of the plant.

There was at least one flowering Echinacea plant at each of the 7 recruitment plots where plants had flowered previously. We also visited 2 recruitment plots at Hegg Lake WMA, a site managed by the Minnesota DNR, where the Echinacea had never flowered in the past. At Hegg West, we discovered a new flowering plant with 7 heads! At these two sites, we used a metal detector to find the nails marking the plot boundaries. We mapped the corners of the plots with the GPS so they will be easier to locate next year. The 6 recruitment plots at Hegg Lake WMA contained a total of 103 flowering plants, Eng Lake WMA had 16 flowering plants, and Kensington WMA had 7 flowering plants in 2022.

Lindsey uses a metal detector to locate the nails marking recruitment plot boundaries
  • Start year: Plantings in 2000-2002
  • Location: Seven study plots on state land with different land use histories: old-field and restored grassland
  • Overlaps with: Demographic census in remnants
  • Data collected: 
    • Plant status (basal, flowering, not present), rosette count, flowering head count, GPS point for each flowering plant in each recruitment plot
    • Recruitment plot demography and survey data are stored in demap
  • Samples or specimens collected: NA
  • Products: A paper (Wagenius et al. 2012) published in Restoration Ecology

You can read more about the fire in recruitment experiment, as well as links to prior flog entries about this experiment, on the background page for this experiment.

2022 Update: Andropogon fire and flowering in exPt08

In summer 2020, Team Echinacea established two plots south of experimental plot 8 for a pilot experiment examining fire effects on Big bluestem (Andropogon gerardii) reproduction. Neither plot was burned during 2020. During spring 2021, we randomly selected the western plot to be burned. In spring 2022, we burned the eastern plot. Spoiler: there was a very distinct rectangular patch of flowering Andropogon where we burned this year. We are very curious whether pollination also improved in this dense patch!

In summer 2022, we revisited the 23 random points in both the eastern and western plots. We counted the number of flowering Andropogon culms within a circular 1m2 subplot centered on each random point (within 56.4 cm) and harvested all seed heads within the subplot. Circle 18 in the eastern plot had the highest count: 96 culms.

Elif x-rays Andropogon in the lab

In the lab, Elif has been developing a protocol for cleaning and x-raying Andropogon. She x-rayed the Andropogon that we harvested in 2020 and 2021, and she found quite a bit of variation in seed set. Stay tuned for more details!

  • Start year: 2020
  • Location: South of exPt08
  • Overlaps with: Andropogon fire and flowering in remnants
  • Data collected:
    • Stakefile for random plot locations: ~Dropbox/geospatialDataBackup2022/stakeFiles2022/stakeAndroPilot2021.csv
    • Culm count data: ~Dropbox\burnRems\pilotAndro\androPilot2022\dataEntry\androPilotData2022.csv
  • Samples or specimens collected: Seed heads collected from 2020, 2021, and 2022 are currently stored in Jared’s office. The 2022 heads have been dried and will be cleaned/x-rayed to quantify seed set.
  • Products: Stay tuned!

You can read more about the Andropogon fire and flowering in exPt08 experiment, as well as links to prior flog entries about this experiment, on the background page for this experiment.

2022 Update: Reproductive fitness in remnants

As part of the Echinacea Project’s long-term efforts to monitor reproductive fitness in the remnant populations, we harvested 330 Echinacea seed heads from 23 remnants during summer 2022. We randomly selected 15 heads from each population where we conducted phenology. If a population had fewer than 15 flowering plants, we harvested a randomly selected head from all flowering plants. In the fragmented populations we study, flowering plants often fail to produce viable seed due to limited mating opportunities. By harvesting seed heads and quantifying seed set, we can better understand how the spatial location and flowering phenology of Echinacea contribute to reproductive fitness.

We are keenly interested in understanding how fire influences reproductive outcomes in fragmented prairies. To this end, we harvested seed heads from 7 populations experimentally burned during spring 2022. We will examine how fire influences mating opportunities and seed set across different populations ranging in size. The heads harvested in 2022 are currently in the CBG lab. Volunteers and students have cleaned, rechecked, and scanned all 330 heads, and they have randomized and x-rayed 249 of the heads so far. We are making great progress!

  • Start year: 1996
  • Location: Roadsides, railroad rights of way, and nature preserves in and around Solem Township, MN
  • Overlaps with: Phenology in the Remnants
  • Data collected: The master data sheet of harvested heads is located here: ~Dropbox\remData\150_clean\clean2022\rem2022MasterDatasheetWithLetNos.csv
  • Samples collected: 330 seed heads were collected and are currently at the Chicago Botanic Garden lab.
  • Products: 
    • We will compile seed set data from 2022 into a dataset with seed set data from previous years.
    • Padmini, a student from Carleton College, used some of the remnant data for her externship project this winter.

You can read more about reproductive fitness in remnants, as well as links to previous flog entries mentioning the experiment, on the background page for this experiment.

2022 Update: Seedling establishment (aka sling)

In 2022, the team continued the seedling recruitment experiment begun in 2007. The original goal of the project was to determine seedling establishment and growth rates in remnant populations of Echinacea angustifolia. Seedling recruitment rates are rarely studied in the field, and this is one of the few studies tracking recruitment in the tallgrass prairie. From 2007 to 2013 in spring, Team Echinacea visited plants which had flowered in the preceding year, and they searched near these maternal plants to find any emerging seedlings. Each fall since then, the team has searched for the seedlings, then juveniles, and measured them.

This summer, my goal was to make the sling search as easy as possible. When assembling the list of plants to visit, I removed 19 sling plants that had not been found for 3 years. This meant that we did not visit any plants at East of Town Hall or Northwest Landfill. Last year, we used our high-precision GPS to record the coordinates of many sling plants, which made them much easier to find. I created a stakefile with a point for each maternal plant and as many slings as possible. We mapped an additional 5 sling plants in 2022, so they can be added to the stakefile for next year.

This year, we visited 56 focal maternal plants at 10 prairie remnants and searched for 102 sling plants, a subset of the original 955 seedlings. The whole team participated, and we completed almost all of the searches in one day, August 31st. I visited the remaining four sling plants at Staffanson on September 1st. Like last year, team members used the demo form to collect data on the visors, and sling records were assigned locs 311 to 412. In total, the team found 50 basal plants and 5 flowering plants!

The million-dollar question: Is there an Echinacea here?
  • Start year: 2007
  • Location: Remnants in Douglas County, MN
  • Sites with seedling searches in 2022: East Elk Lake Road, East Riley, KJ’s, Loeffler’s Corner, Landfill, Nessman, Riley, Steven’s Approach, South of Golf Course, Staffanson Prairie
  • Overlaps with: Demographic census in the remnants
  • Data collected:
    • The data were collected on a visor using the demo form. The team recorded plant status (can’t find, basal, dead this year’s leaves, dead last year’s leaves, flowering), number of rosettes, leaf count, nearest neighbors, and head count, if flowering.
    • Scanned datasheets are in Dropbox: ~Dropbox\remData\115_trackSeedlings\slingRefinds2022
    • The 2022 demography data are located here: ~Dropbox\remData\115_trackSeedlings\slingRefinds2022\slingRefindsData2022WithSlingCd.csv
    • The 2022 stakefile is here: ~Dropbox/geospatialDataBackup2022/stakeFiles2022/stakeSling2022.csv
    • Surv data for sling plants mapped in 2021 and 2022 have been added to demap, and demo data will be added shortly
  • Samples collected: NA
  • Team members who searched for slings in 2022: Alex Carroll, Geena Zebrasky, Johanna Steensma, Lindsey Paulson, Daytona Hoberg, Amy Waananen
  • Products:

You can read more about the seedling establishment experiment, as well as links to prior flog entries about this experiment, on the background page for this experiment.