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There was one project we did not get to this year. In the summer of 2012, field intern Kelly Kapsar observed flowering times for Echinacea in burned and unburned areas of the Staffanson prairie preserve. At the end of the summer, she collected the flowering heads in order to assess the relationship between flowering time and seed set. Various students have worked on aspects of the project. In November, Mindy Runge and Ale Mendoza (Lakeforest College) extracted and weighed achenes (click here to see their poster). In December, Marie Schaedel (Carleton College) weighed additional achenes and assessed our methods of judging whether an achene is full or empty (click here to read her results ). Most recently, Jill Pastick (Lakeforest College) finished extracting achenes and helped organize the collection.
These steps (extracting and weighing achenes) allow us to draw a relationship between flowering time and seed set (i.e. the proportion of full vs. empty achenes). The next step of this study will be to germinate the achenes and plant them in the field. Unfortunately, that will have to wait until next year. In the meantime, the collection of weighed and organized achenes will be stored in the freezer.
Hi everyone,
I presented a poster at MEEC 2013 (which Katherine wrote on in the previous entry) and just got back from another poster presentation at Chicago Area Undergraduate Research Symposium (CAURS) today!
Here’s my poster – enjoy looking at it to see what I found out from my summer fieldwork!
Wang_MEEC2013-Poster36x44-pdf.pdf
This past weekend, three students associated with the Echinacea Project presented their work at the Midwest Ecology and Evolution Conference at Notre Dame.
Kelly Kapsar (Carleton College, 2014) spent the winter analyzing her data on flowering phenology in prairie remants and presented her results in a poster.
Maria Wang (Northwestern, 2013) presented the results of her undergraduate honors thesis on pollen limitation in the prairie grass Dicanthelium.
Master’s student Katherine Muller gave an oral presentation on her research on the relationship between Echinacea and its specialist aphid.
I should mention that Maria was recently accepted as a Master’s student in the Northwestern Program in Plant Biology and Conservation. She will graduate this summer and remain in Chicago another year to finish her M.S.. She will be working with Dr. Nyree Zerega investigating the genetic origins of tropical crops. Although we will miss her in the Echinacea Project, we wish her the best in her next endeavor.
This January Stuart and Gretel kindly hosted me in Chicago and gave me the opportunity to spend a few weeks working in the Echinacea Project lab continuing my research from the summer. Here is my final paper with some interesting results.
Sanford-Long_EchinaceaHybridization.doc
During the summers of 2011 and 2012, I conducted a survey of aphid infestation in a section of the main experimental plot to track, among other things, seasonal changes in the distribution and abundance of Aphis echinaceae on Echinacea. With help from members of team Echinacea, I conducted 6 bi-weekly surveys in 2011 and 3 monthly surveys in 2012. In both years there was a sharp rise and fall in the frequency of aphid infestation. The plot below shows the percentage of plants in the survey area observed to have 1 or more aphids on each dates. In 2011, the peak of aphid infestation (i.e. when the highest percentage of plants hosted aphids) was around August 12th. In 2012, the peak date of aphid infestation occurred some time between July 13th and August 9th. I was not able to observe the peak directly due to a sudden die-off of aphids before my third survey. I estimated the peak frequency of aphids as the percentage of plants with live or dead aphids on August 10th (indicated by the asterix and x-error bar).
I was also able to get a sense of aphid phenology from my aphid addition/exclusion experiment. In 2011 and 2012, I added or excluded aphids from 100 plants that were not flowering in 2011. The graph below shows the mean abundance of aphids in each experimental group over the summer of 2012:
Based on this graph, I estimate that the peak of aphid infestation for 2012 occurred around July 22nd (202 days after January 1st), about two weeks before last year’s peak.
Hi everyone,
Maria here at CBG. On Tuesday, I came back from Thanksgiving break to find that one of the Dichanthelium plants in the growth chamber was flowering like crazy!
So many flowers! It was also interesting that the plant that flowered looked more stressed (yellow leaves) than some of the other plants.
Today, I collected some pollen (shook the spikelets) on glass slides, stained them with 0.1% toluidine blue, and looked at them under the microscope. It was amazing to see the stained pollen, and how different the viable and inviable pollen looked! I wish I had pictures. I will be learning how to take digital microscopic images (hopefully tomorrow?). So hopefully I’ll be able to stain pollen from all flowers tomorrow, take pictures of the stains, and count pollen to get a sense of levels of viability in Dichanthelium pollen.
Maria here.
Woke up this morning to some rumbling thunder in the distance.
The skies looked grey, but nothing too bad. We discussed how to do all the things we had to do at Staffanson: demo rechecks, harvesting Kelly’s Echinacea heads, removing twist-ties and flags from heads/plants that Kelly won’t harvest, figuring out 6 nearest neighboring Echinacea plants to each of Kelly’s plants that was going to be harvested, and pulling up ant traps. Whew!
We did some individual project stuff from 9 to 11am. Jill finished up sorting ants. Katherine and Kelly went to NWLF and NNWLF to pull ant traps and remove twist-ties from heads. I was in CG 99 South, measuring Dichanthelium from my maternal lines experiment, and got 4 rows done before 11am.
We set off for Staffanson, all 5 of us cozy in the truck. The corn and perennial weeds greeted us happily on the dirt road leading into Staffanson. Jill went to pull up her ant traps and then helped Kelly to remove twist-ties and flags. Stuart, Katherine and I brought out Sulu (the GPS), R2D2 (the netbook), and paper datasheets, and tried to figure out how to determine the 6 nearest neighbors to Kelly’s harvest heads. We concluded that the most efficient way was to use R to determine the 6 mapped nearest neighbors, obtain the distance to the 6th neighbor, then use a reel tape to measure out the distance and search to see if there are any other nearest neighbors closer than the mapped one. We would have to do it another day.
Here’s a fancy spider Stuart found on his knee today. Photo courtesy of Katherine.
On the way back for lunch, Stuart and Kelly belabored the pros and cons of color coding the top and bottom GPS poles.
After lunch we set out for Staffanson again. Kelly worked solo to harvest heads, while the four of us split into 2 teams (1 GPS + 1 clipboard) to do demo rechecks. After a little while, it started sprinkling and we heard some distant portentous thunder, so we turned back and left Staffanson.
Back at Hjelm House, Jill and Katherine cleaned up the ant traps and went to pull ant traps at Nessman. Stuart demonstrated dissecting achenes from Echinacea heads for Kelly, so she can dissect the heads she harvested when she’s at Carleton.
Lastly, as requested by Stuart, the “Sync Your Visor” song I came up with as an alternative to “Sync, Sync, Visor Sync”:
(To the tune of “Oh My Darling Clementine”)
Sync your visor, sync your visor,
Sync your visor everytime;
Data lost and gone forever
Don’t be sorry – sync it now!
Any suggestions for improvement are much welcome.
The last flowering plant in CG1 put out its last anthers today (August 27, 2012). It had been flowering over a week longer than any of the other plants we monitor! This marks the end of the flowering season for Team Echinacea, but we’ve still got lots of work left to do!
Happy Friday! Today was our fourth day “going solo” while Stuart is away in Chicago. In the morning, we finished up seedling searches at East Elk Lake Road. That’s two sites down! In the afternoon, we continued working on demography re-checks at some of the smaller sites. Basically, demography re-checks consist of fixing any errors that we might have made during the initial round of demography (i.e. one person said a plant had two heads while another said it had four), but it also allows us to go back and find basal plants that have flowered previously. By checking on these plants (or a random subset of these plants) each year, we can get a better idea of how often a plant flowers and the survival rate of flowering plants. Today we finished demography re-checks at Loeffler’s Corner (East and West) and Yellow Orchid Hill.
Here’s a picture of the crew at Yellow Orchid Hill after a hard day’s work:
The past couple of days have been lovely for outdoor work–sunny, cool, a little breezy. On Monday we said bon voyage to the Wagenius family as they prepared for their trip back to Chicagoland. Stuart will be back next week, but Gretel and the kids are done for the summer. Now there are five of us and no shortage of work to do.
Monday morning we went to the site off of hwy 27 to take demography data on plants that flowered last year and reconcile errors from this year’s demography census. With two teams working with the GRS-1 GPS units, the task went quickly and smoothly.
We spent Monday afternoon re-finding seedlings at KJ’s. This is a particularly challenging site because there is a high density of plants in a small area. We continued the endeavor this morning, and I’m happy to say are nearly finished. We should be able to defeat the beast tomorrow morning.
Here are Jill and Maria looking for seedlings at KJ’s. Red flags mark completed focal plants.
This afternoon we performed some routine maintenance of the main experimental plot, pulling out flags that marked plant we could not find. Then we spent the rest of the afternoon on individual projects.
Karen Taira, who came up last week, has been spending her days working on her pollination experiment involving several species of Helianthus. Her field story of the day was that she found a pile of entrails next to one of her experimental plants. Apparently they were bigger than a prairie dog’s and smaller than a human’s. Perhaps it’s a new form of sacrificial sun worship–Praise Helianthus!
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