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So it begins! Two new externs have joined Team Echinacea from Carleton College. We (Mikaela and Emma) will be here every day for the next three weeks, and are excited to discover new revelations for the Asynchrony, Isolation and Incompatibility experiment.
So far, most of what we’ve discovered is that cleaning Echinacea seed heads is tedious. Two days in, we have cleaned 36 seed heads; scanning them was a nice relief from the monotony. We think we could get through all 110 by the end of this week.
Although yesterday was quiet, there was a little bit of commotion: Mikaela’s second seed head had a rare deformity. Many of the achenes were uninformative. This means they were aborted part of the way through formation, so it cannot be determined whether they were fertilized. After minutes of puzzled deliberation, Stuart, Amy and Scott decided to keep them in the sample.
 Four uninformative achenes compared to one normal, small-to-mid-size achene. Because of their immaturity, the florets are still firmly attached. In contrast to yesterday, today there were quite a few volunteers and a couple of students who we got to meet. It was nice to talk to other people who were involved in and excited about this project. We also got to hear about other experiments going on in the lab besides our own.
Today’s seed cleaning also presented an exciting moment: just moments after Amy told us about last year’s larval discoveries, we each found a live larva residing in the heads we were cleaning. We’re thinking about raising these mystery larva so we can finally learn just what they are. Hopefully we’ll have more success than last year’s effort!
 Our two larva. Emma’s is the tiny brown one on the right, and Mikaela’s is the pink one hanging out on a makeshift habitat of chaff. We are grateful for this opportunity to contribute to and learn from the project, and are looking forward to the next three weeks!
Thanks for the warm welcome,
Mikaela and Emma
Dear Flog,
Last time I mentioned in passing that Stuart, Amy, Scott, and I had been discussing papers about fire and its potential impact on the reproductive fitness on Echinacea plants. This week I will go into greater detail about what I’ve learned about fire and what our data can teach us about how it impacts prairie health.
Some of our studies taken from previous years have shown us that, even when there are enough bees to carry pollen from plant to plant, Echinacea plants can have difficulties receiving pollen from potential mates. There are a few reasons for this. In our fragmented prairie remnants, Echinacea plants are often far enough apart that pollen collected by a bee will often fall off before it can reach another Echinacea flower. Echinacea plants may also flower in different years, or at different times in the season. This can prevent mating even between close flowers. This mate availability problem is compounded by the fact that Echinacea is self-incompatible, meaning a plant cannot pollinate itself or its close relatives. This means that if a plant flowers and fails to find mates, all the energy it expends to flower and fruit results in no offspring. This is an extraordinary energy cost for no payoff.
Data we have collected seems to suggest that fires may help perennial prairie plants like Echinacea find other mates. Explosive flowering after a large burn is typical for prairie plants. There is some evidence that increased availability of nutrients from burned organic matter and the increased availability of sunlight provide resources for a plant to invest in a costly reproductive structure like a flower. This is probably no different for Echinacea. However, as an added bonus, some of our data seems to show that this explosive flowering may reduce the reproductive isolation of Echinacea plants by increasing the number of synchronous flowering plants. Thus, fire helps Echinacea successfully seed by increasing the number of available mates. Really cool!
The tendency of Echinacea to flower synchronously after a fire could be the result of natural selection, or simply a byproduct of the excellent growing conditions created by fire. In either case, this knowledge affirms how important fires are to prairie ecosystems. The Echinacea Project, through projects like SppBonus, hopes to further elucidate these mechanisms through which fire improves prairie health.
Until next time!
Sam
Citations:
Wagenius, S. and Lyon, S. P. (2010), Reproduction of Echinacea angustifolia in fragmented prairie is pollen-limited but not pollinator-limited. Ecology, 91: 733–742. doi:10.1890/08-1375.1
https://echinaceaproject.org/pub/wageniusAndLyon2010.pdf
Ison, J.L., S. Wagenius, D. Reitz., M.V. Ashley. 2014. Mating between Echinacea angustifolia (Asteraceae) individuals increases with their flowering synchrony and spatial proximity. American Journal of Botany 101: 180-189.
https://echinaceaproject.org/pub/isonEtAl2014.pdf
Part 1. I couldn’t stay away from the Echinacea Project too long. As I’m positive you want to hear both about my poster that I will be presenting at MCMS tomorrow at the University of Chicago and my adventures in Chicago, I will share both. As I arrived at the airport to fly to Chicago, I realized I had forgotten my cell phone. I thought to myself, I lived most of my life without a cell phone, I can do it another day. After arriving in Chicago, I had thankfully packed a dollar in quarters, so I was able to use a pay phone (yes, those still exist) to call a cab. While I did struggle to understand the technology, I was finally able, after spending my only dollar in quarters, to procure transportation to the Chicago Botanic Gardens. I was left penniless, phoneless, and with only a laptop and my knowledge of Chicago (this, by the way, was absolutely nil). After making a successful rendezvous with the team, I enjoyed a lunch and tour of the lab. It was great to see everyone again.
Part 2. After figuring out the best way to get to my destination at the University of Chicago, I jumped on the purple line, confident that, after a quick jaunt on the green line, all I’d have to do was walk a block or two to the hotel, where dinner awaited me. I hopped off the train, and quickly realized that the area had been highly developed since the last google street image had been taken, unless my memory of the picture failed me. Ah well, I thought, I wrote down the street that will get me to my hotel, it’s just east of here. The street just east was not the correct street. Maybe the map I saw was just wrong. By the next street, I knew I was in the wrong place. Thankfully a friendly man suggested a bus that would take me five miles to the east, where I thought I was getting off. Yes, I had taken the wrong train. All was well and good until I hopped on the bus and realized that I was penniless, with no money for a fare. Again, the bus driver was a greatly friendly man, and I rode the bus without a fare. Sailing was smooth from there on out.
Tomorrow I will present my findings on how edge effects play a role in the style persistence and pollen limitation of Echinacea at the Midstates Consortium for Math and Science. Style persistence decreased as plants were farther from habitat edges, demonstrating a spatial pattern in pollination. Attached is my poster. stylepersistenceedgeposter
Off to share a room with someone I haven’t met yet. Day in the life.
No explanation needed. Great to see y’all again.
Hey Flog!
My name is Sam Hamilton, and I am a Northwestern senior doing research in the Echinacea Project lab this quarter. My project specifically seeks to understand the relationship between prairie fires and reproductive success of flowering plants using our model organism A. Echinacea. This is an important relationship to understand because, while historically fires were an integral part of the prairie life cycle, today’s isolated prairie remnants are often never burned. This could have a large impact on the success of shorter plants that rely on the extra sunlight and nutrients that a burn year supplies to flower and germinate. This quarter, I will be collecting the data from seed heads collected this year and analyzing it along with data collected in previous years to draw my conclusions.
I am also looking at the reproductive success of Echinacea flowers collected from the bottom, middle, and top of each head. In Echinacea, flowers mature first at the bottom and slowly develop towards the top over time. This allows us us to deduce when a plant was pollinated best during the season. I’ve been hard at work the past month cleaning seed heads and separating their achenes into top, middle, and bottom sections for later analysis. It’s been a lot of work, but the great company has kept it fun!
Until next time!
-Sam
Myself with Susie, Char, Aldo, and Scott. (Left to Right)
One month of cleaned and organized achenes.
After a slow start, Amy and I did demography at some of the recruitment plots near Hegg Lake and p2. The flowers in plots HE and HS, near P2, were doing especially well; we counted a total of 34 flowering plants combined in those two plots, with several having multiple heads, and were able to find nearly all of the plants there. We also returned to a stand of Cirsium hillii near p2 that we measure each year, and found that at least three of our study plants flowered recently. Whether they flowered this year or last year is not yet clear — the leaves definitely looked gray and crispy. Stuart made the long trek back from Chicago today and harvested some Astragalus canadensis for broadcasting and corralled an escaped goat.
The highlight of today was finding a flowering (second day!) Echinacea near the Cirsium study area. We finished phenology in all of the remnants and plots several weeks ago, and have even harvested a good number of heads that are ready to drop their achenes. How this one is flowering so late in the season is a mystery — it may have to do with some recent mowing. We look forward to revisiting this plant to see if, by some miracles, it gets lucky and some of its styles shrivel.
Flowering (second day!) Echinacea found today near P2. Outrageous! Amy and Chek look for Echinacea from the car.
Today was probably the coldest day of fieldwork we have had all summer, a cold front passed through on Wednesday and left us with a cloudy 60 degree day. For those team members who are more accustomed to hotter summers today was a little bit of a shock.
We went out to do total demography at Staffanson Praire Preserve, our goal while doing total demo is to census all of the plants that have flowered sometime in the last 20 years. It’s a big project, at Staffanson alone there are just over one thousand locations to visit. While not all of these locations still have a plant it is awesome to see a tag around a plant that was put there in 1996 or 1997.
Even the flowers are cold! We made a huge dent in the number of locations at Staffanson, of the 1054 locations we visited 435, nearly half done!
Scott stakes locations while Amy does demography on the plants at each location
I am excited to present to you my summer 2016 research proposal. While previous research has shown that isolated Echinacea plants and populations experience reduced reproductive fitness, we have not looked at what influence edge effects may have on Echinacea populations. Findings presented in Ison and Wagenius 2014 showed that plants in P1 experienced slight edge effects on seed set. My research this summer will use style persistence data collected from all remnant sites and quantify the relationship between distance of an Echinacea plant from a habitat edge and average style persistence. This will help us understand if fragmented populations are being harmed by yet another factor. Hopefully you find this topic as interesting as I do.
JamesEckhardtProposal2016
Here is a proposal for a fun project. It involves using demography data from this (and prior) years to estimate the growth rates of each of the remnants individually. Actually, that’s basically the whole project. Action items for the next month include: reading technical manuals with specifics on implementing aster models (see the list of project publications if you want to read them for me on your own).
scott_proposal_1
In other Scott-research related news, I will also try modeling fitness of various Hesperostipa spartea crosses in experimental plot 1. Just today I got a list of positions of plants found alive in 2016 — my plan in the near future is to search positions in the plot where plants were found alive in 2011 but weren’t found in 2016 to assess mortality. Keep your eyes open for another action-packed research proposal for this porcupine grass-ey project.
We met a half hour early today so we could do pollinator observations during what we thought would be their peak time. We were wrong. Hardly any bees were out and about on this very windy morning. Everyone finished around 10:30 and we met down in P1 to weed the birdsfoot trefoil.
 This little mouse greeted us in G3 this morning. The lunch table was very crowded today as we had a number of special visitors. Ruth Shaw, Dan (a grad student from U of M), and Amy and Brad Dykstra all came to help out. They also brought yummy chocolates and muffins for a lunch treat.
After lunch, everyone set out different ways. Some people went GPSing and some went to catch pollinators. I got to stay back to teach Lea, Scott, Alyson, and James my special talent, aphid exclusion and addition. Last summer, I worked a lot on the aphid project so it was a lot of fun to do again! Alyson even sang to the aphids to sooth them into their new homes. Roxy saw how much fun we were having and decided to join us for awhile in P1. We found 70/100 original addition/exclusion plants, including 33/50 addition and 37/50 exclusion ones.
 Here’s some aphids I found on a collection plant in P1.  Team members learning the ways of aphids. Today I also took my first trip to the infamous bog with Alyson and James! Roxy, the bog dog, took me on a wonderful tour of the place. On our way up, we stopped to pet the goats.
 Alyson trying to escape the treacherous bog waters.  Scape Goat eats out of James’s hand.
While looking for some information about the establishment of the Stipa experiment, I encountered an x-ray image of a few Stipa propagules (Hesperostipa spartea). Check it out…
 An x-ray image of a Stipa propagule (Hesperostipa spartea)
I also found some x-ray images of Echinacea angustifolia achenes. There are higher resolution images than the ones we now take for data analysis.
An x-ray image of achenes & other stuff from an Echinacea angustifolia head with higher magnification
An x-ray image of achenes & other stuff from an Echinacea angustifolia head An x-ray image of achenes & other stuff from an Echinacea angustifolia head
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