2017 update: Pollen addition and exclusion

Echinacea head with pollinator exclusion bag.

Does receiving the maximum amount of pollination vs. no pollen at all affect a plant’s longevity or likelihood of flowering in subsequent years? We are trying to find out in this long-term experiment, but flowering rates have been so low in the past few years we are not learning much.

This summer, only three plants flowered of the 27 plants remaining in the pollen addition and exclusion experiment. We continued experimental treatments on these flowering plants and recorded fitness characteristics of all plants in the experiment. Of the original 38 plants in this experiment, 13 of the exclusion plants and 14 of the pollen addition plants are still alive.

In this experiment we assess the long-term effects of pollen addition and exclusion on plant fitness. In 2012 and 2013 we identified flowering E. angustifolia plants in experimental plot 1 and randomly assigned one of two treatments to each: pollen addition or pollen exclusion. When plants flower in subsequent years they receive the same treatment they were originally assigned. Because flowering rates have been so low in 2016 & 2017, differences in flowering due to treatment are not detectable.

Start year: 2012

Location: Experimental plot 1

Physical specimens: We harvested three flowering heads from this experiment that will be processed with the rest of the experimental plot 1 heads to determine achene count and proportion of full achenes.

Data collected: We recorded data electronically as part of the overall assessment of plant fitness in experimental plot 1. We recorded dates of bagging heads and pollen addition on paper datasheets.

You can find more information about the pollen addition and exclusion experiment and links to previous flog posts regarding this experiment at the background page for the experiment.

2017 update: Aphid addition and exclusion

Aphids on an Echinacea leaf

This summer Team Echinacea continued adding and excluding aphids to plants in the experiment that Katherine Muller started. In 2011, Katherine Muller designated a sample of 100 Echinacea plants in experimental plot 1 for aphid addition or removal. The presence or absence of these aphids was maintained by team members once a week in the summer of 2017, for a total of 7 weeks from early July to mid August. We maintained addition on 31 plants and exclusion on 30, for a total of 61 plants. Will Reed set up a data entry system where we could enter data twice from the paper sheets and check for data-entry errors. In early October, Lea Richardson and Tracie Hayes recorded signs of senescence in the leaves of treatment plants. This data can be combined with data from our common garden measuring data to explore the richness of the Echinacea-aphid relationship.

Aphis echinaceae is a specialist aphid that is found only on Echinacea angustifolia. Read more about this experiment.

Start year: 2011

Location: Experimental Plot 1

Overlaps with: Phenology and fitness in P1

Data collected:

  • Aphid counts for each treatment plant on each observation day, on paper
  • Aphid counts recorded in csvs, on the teamEchinacea2017 dropbox
  • Leaf senescence data, recorded on paper
  • Initial and final assessment of aphid counts on treatment plants, recorded on paper
  • Aphid counts also included in p1 measuring data


  • 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
  • 2015 poster by Daniel Brown and Kyle Silverhus (Lake Forest College) on achene and seed set differences on treatment plants

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.

Extreme Project: X-Ray

Howdy all you Flog Followers,

I have returned from summer break and feel more ready than ever to dive back into the Extremes Project!

Once all the achenes were randomized, I moved on to the next step: X-Raying all of the achenes.

First, I put all of the informative achenes, in the clear plastic bags, onto a gridded sheet. On the sheet, the achenes are placed in numerical order. This keeps the x-ray process fast and easy to follow.

Image 1:

Next, I took all of the sheets into the lab room with the X-ray machine and computer.

Process for one scan (one scan = one sheet of paper, as seen in Image 1):

  • Uncover and Turn on the X-ray machine, Scanner, and Computer and ensure that they are all set up properly.
  • Block off the red lights that create a grid of lines within the x-ray machine. This is to avoid any visual obstructions. I used sticky notes (easily removable).
  • Put the sheet of achenes and the film sheet (the Echinacea Project team has a personal, newer sheet to use!) into the x-ray machine, make sure to line up properly within the tape marks on the bottom of the machine and close the door completely.
  • Run the x-ray by pressing the appropriate buttons on the computer.
  • After a handful of seconds (I believe 15 seconds) the x-ray is complete.
  • Next, move onto the Scanning Machine.
  • Remove the film sheet from the x-ray machine and put it into the scanner. To initiate the scan, film sheet will require some accurate alignment and positioning into the machine.
  • Once complete, the scan will show up on the computer! The scan will look similar to Image 2.
  • It’s key to check the quality of the x-ray, if achenes are too difficult to see a new x-ray should be performed.
  • Crucial!! Be sure to save each x-ray to the appropriate folder !!
  • Before leaving, make sure to remove the sticky notes, power off all of the machines, and put the covers back onto the machines. Essentially, leave the space as you found it, or cleaner!

Image 2:

In this image there are four separate bags of achenes. Even within these four bags there is a large difference to the number of seeds found in each bag. Of the cluster of achenes on the bottom right, the majority of those achenes are full with seeds (the opaque white filling). However, directly above on the top right, all of the achenes are empty.

I am excited to see all of the variation amongst this seed set and will be moving onto analysis in the next few weeks!

Till next time folks,

Nicolette McManus


2017 update: Cirsium hillii fire & fitness

This year we monitored the original 28 C. hillii rosettes at Hegg Lake WMA to check the fitness and persistence of our original individuals/population. Presently, 10/28 rosettes remain, all as non-flowering basal rosettes. For each rosette, we measured the length of the longest axis and the corresponding perpendicular axis. No burns were conducted this year.

This experiment assesses effects of fire on the fitness of Cirsium hillii (Hill’s thistle) plants at Hegg Lake WMA. Like EchinaceaC. hillii inhabits dry prairies, but Hill’s thistle is listed as a Species of Special Concern in Minnesota and little is known about how it responds to fire. Burn and non-burn units were created prior to an experimental fall burn conducted by the Department of Natural Resources (DNR) in 2014. That year, we mapped 28 C. hillii rosettes (basal and flowering).

The distribution of Cirsium hillii, a rare endemic to the Great Lakes region.

Last year was also a non-burn year, although of rosettes found, there were three flowering rosettes. It’s challenging to determine cases of mortality with this species, since C. hillii is clonal, and it’s possible that each rosette is not a unique individual.

In 2015, Abbey White found that there was only one or two individuals in our C. hillii “population!” We don’t know of any other C. hillii populations in Douglas County. We are possibly monitoring the last individual in the area.

You can find out more about Cirsium hillii fire & fitness and read previous flog posts about it on the experiment background page.

What we did this summer

Over the next several weeks we are going to post updates on all the projects we worked on during summer 2017. Whew we did a lot–it might take a couple of months!

Team Echinacea summer 2017

Put a bookmark on our update page to stay caught up. We’ll post all updates on that page.

Two new projects to look out for are Richardson’s “Liatris and Solidago phenology” and “Pollinators on roadsides.” Also, we’ll recap Barto’s & Braker’s REU projects. Stay tuned!

We didn’t work on the project Fire & flowering at Staffanson Prairie Preserve
or on Mating compatibility in remnants this summer. We didn’t do the first one because no burns were conducted at the preserve before this growing season. We contemplated assessing compatibility for another year, but there seemed to be more things that we wanted to do than there were people and time to do them.

Art is counting away

Art is spending the morning today counting achenes at the computer. One great thing about counting achenes is you can still tell stories while you’re doing it, and Art has quite a lot of funny and interesting stories about his earlier days volunteering at the garden.

Art counting Echinacea achenes in the lab

Char cleaning Echinacea heads

Today Char and Susie have been cleaning Echinacea heads from 2016. Char is interested in Art’s idea of using the seed counter to count out achenes once they have been cleaned. She wants to know if the seed counter will be able to count achenes that come from small heads that have tons of tiny achenes. An experiment is in the works!

First day at the garden

Hi flog!

Today Team Echinacea met at the garden for a day full of exciting meetings and orientation. I got in around 8 to start learning my way around the Plant Science Center, and then Gretel, Stuart, Lea, Kristen, and I met to recap the summer and talk about goals for the fall. We started planning our trips back to Minnesota to finish up field work and burn a few of the experimental plots. Before lunch, we got demonstrations by a few of the volunteers of the ACE protocol, including how to clean Echinacea heads, count achenes, and randomize achenes.

After lunch we continued meeting to discuss project ideas and talk about our weekly schedules. We’re all pretty ambitious with our ideas and goals for the fall, but Stuart believes it’s possible. Can’t wait to get started!



Today was a busy day for the three of us: Kristen, Alex and I. But we got a lot done! I spent the morning at Staffanson working on Lea’s Liatris and Solidago phenology/harvest while Kristen and Alex did total demo at East of Town Hall. Later they shot a few extra plants at On 27 while I started remnant harvest. I only got through about half of the sites before heading back to the Hjelm House to meet up for lunch. We took a quick lunch and then got back at it. I finished up remnant harvest and then we started a few sling sites. Even with some GPS trouble, we got through seedling searches at KJ’s, NWLF, and ETH.

Looking for seedlings at KJs.

Sling Mania

Today was another chilly day at the Echinacea Project with highs reaching up into the low 60ºs. Tracie and I spent the morning working on harvesting Lea’s Aster Phenology at SPP. Many of the Liatris are finished flowering and ready for harvest, but some of the Solidago plants still have at least another month or two before they will be ready.

Prenanthes racemosa

In the afternoon we spent our time out at Stephen’s Approach working on more seedling refinds. Between Tracie and I, and later also Stuart and Alex it took us about 3 hours to complete 13 focal plants. This is one of the more challenging activities that we do at the Echinacea Project, however, the glory of finding one of last year’s plastic swords or toothpicks is immeasurable.

Actual seedling refinds map found today. Luckily another map was found for the same site with the correct seedling locations.