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 Echinacea pallida observed at Hegg Lake. This summer, we remeasured plants in experimental plot 7 at Hegg Lake. These plants are hybrids of Echinacea angustifolia (native) and Echinacea pallida (non-native, but planted at a nearby restoration). Shona Sanford-Long performed these crosses in 2012, Jill Pastick germinated the seeds that winter, and Stuart planted the seedlings the following spring. It is not yet known how the introduction of this non-native species will affect local Echinacea angustifolia populations. The survival rates and reproductive fitness of these plants can tell us how well the hybrids can compete with the native species. We have returned to the plot each of the last three years and measured the plants found there.
198 of the original 294 planted seedlings (67.3%) were found this year. The table below shows the fate of each cross-type in 2016 — the first name in the cross type is the maternal species, and the second name is the paternal species (e.g., ‘ang_pal’ is angustifolia mother and pallida father). These plants were measured on August 3rd and rechecked on September 2nd. No plants flowered this year, meaning that we must wait longer to assess seed set and reproductive fitness.
Cross Type
Found16 ang_ang ang_pal pal_ang pal_pal
no 34 10 20 32
yes 37 21 65 75
Start year: Crossing in 2012, Planting in 2013
Location: Hegg Lake Wildlife Management Area – Experimental Plot 7
Overlaps with: Echinacea hybrids: ex Pt 6; Echinacea hybrids: ex Pt 9
Data collected: Rosette number, length of all leaves, herbivory for each plant collected electronically and exported to CGData. Recheck information for plants not found was also collected electronically and stored in CGData.
Products: Taylor Harris’s 2015 poster demonstrating fitness benefits of pallida parenthood.
You can find more information and links to previous flog entries involving experimental plot 7 on the background page for the experiment.
Inbreeding has negative effects on Echinacea, leading to reduced survival and fitness. In isolated populations, populations could benefit from genetic diversity introduced by mating with individuals from other populations (“outcrossing”). However, gene flow from other populations may compromise a population’s adaptation to its local environment. Amy Dykstra designed an experiment to test how mating with individuals from other populations affects Echinacea fitness. In the summer of 2008, Amy and Team Echinacea performed 259 crosses between individuals randomly selected from 6 of the largest remnant populations. That fall, Amy planted the offspring of these crosses (15,491 achenes) into an experimental plot at Hegg Lake WMA.
Every summer, including 2016, we measure plant status, number of rosettes, number of leaves, and length of the longest leaf of the individuals in the plot. We also note damage (herbivory) to the leaves.
 Hegg Lake WMA (Amy’s plot is visible on the horizon to the right of the lake) Start year: 2008
Location: Hegg Lake WMA
Overlaps with: Dykstra’s local adaptation
Data collected: We collected plant fitness measurements (plant status, number of rosettes, number of leaves, and length of longest leaf) electronically.
GPS points shot: We shot points at all surviving plants (and a few that we couldn’t find this year, but will check next year) in the experimental plot, which will make finding and monitoring these plants much more efficient in the future. The points are stored in ‘AMYSCROSSIG_20160712_SULU.tsj’ and some rechecks to those points are in “AMYSCROSSING_20160830_SULU.tsj’.
Products: Read about Amy’s analysis of the interpopulation crossing experiment in her flog post from last summer.
You can find more information about Amy’s experiment and links to previous flog posts regarding this experiment at the background page for the experiment.
In 2008, Amy Dykstra began an experiment to study how adapted Echinacea populations are to their local environments. She collected achenes from three populations distributed across a wide section of Echinacea angustifolia’s range, from Western South Dakota to our study site in Western Minnesota. She established a plot near each collection site where she sowed achenes from all sites. Since then, Amy has assessed survival and fitness traits of the individuals in her plots annually.
The exciting news about this experiment is that three plants flowered this year: two had one head each, and one had vertical development of its stem, but did not form a flowering head. All three were in the Western South Dakota plot and originated from Western Minnesota seed. This summer was the first time that Amy saw any flowering in this experiment. We hope for more flowering in the future so that Amy can analyze how local adaptation affects adult life stages of Echinacea.
 Amy saw the first flowering plants in the local adaptation experiment in 2016 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: Amy collected plant fitness measurements (plant status, number of rosettes, number of leaves, and length of longest leaf) electronically.
You can find more information about Amy’s local adaptation experiment and links to previous flog posts regarding this experiment at the background page for the experiment.
This experiment assesses effects of fire on the fitness of Cirsium hillii (Hill’s thistle) plants at Hegg Lake WMA. Like Echinacea, C. 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 DNR in 2014. That year, we mapped 28 C. hillii rosettes (basal and flowering).
We revisited the locations this year, a non-burn year, and found three flowering rosettes. Several of the rosettes we found in previous years weren’t present this year. We weren’t sure if this was an indication of mortality since C. hillii is clonal, and it’s possible that each rosette is not a unique individual. Last year, Abbey White, a masters student in the Plant Biology and Conservation program at Northwestern, she analyzed the genetic diversity of tissue samples from each rosette. Based on a conservative delineation of genotypes, she found that there was only one individual in our C. hillii “population!” If she uses a more liberal approach, there are two individuals. We don’t know of any other C. hillii populations in Douglas County and are possibly monitoring the last individual in the area.
 The distribution of Cirsium hillii, a rare endemic to the Great Lakes region (yellow counties are where C. hillii has been found) Start year: 2014
Location: Hegg Lake WMA
Overlaps with: fire and flowering at Staffanson Prairie Preserve
Data collected: We measured the length of the longest axis of a basal rosette and the corresponding perpendicular axis. These data were recorded electronically in a memo and are backed up in Handspring.
Products:
You can find more information about our experiment on how fire affects the fitness of Cirsium hillii and links to previous flog posts regarding this experiment at the background page for the experiment.
In 2016, we continued our ongoing study of mating compatibility in the remnants that began in 2014. This experiment is designed to assess population level compatibility and to investigate whether the difference in the timing of flowering (phenology) and the distance between plants predict whether mating will be successful, or the cross will be compatible. This year, we randomly selected 10 focal plants from remnant populations and chose their four nearest neighbors to be pollen donors.
We conducted this study in six remnant populations with approximately ten focal plants at each for a total of 279 pairwise crosses. Occasionally we were unable to collect pollen from the four nearest neighbors of the focal plant because they flowered asynchronously with the focal plant, and in those cases we chose the nest nearest individual available. Excluding all other pollinators, we performed hand-crosses between the focal plants and their pollen donors and assessed style persistence the following day to evaluate the compatibility of each cross.
We observed wide variation in compatibility among sites, with focal plants at some sites compatible with an average of 90% of their nearby neighbors and only 64% at others. Further analysis will tell what relationship this pattern might have with individuals’ synchrony of flowering and proximity to mates!
 We exclude pollinators from our focal plants and pollen donors using bridal veil material, an evocative method rich with symbolism of purity and loss of innocence. Start year: 2014
Location: large remnant populations in Solem Township, Minnesota
Data collected: We collected data about the identities of the individuals and outcome of crosses on paper datasheets. The phenology data was collected electronically. We used GPS units to collect spatial data about individuals’ location and isolation.
Products: We entered the data from 2016 and it is ready to be compiled and analyzed with the 2014 and 2015 datasets.
You can find more information about our compatibility experiment and links to previous flog posts regarding this experiment at the background page for the experiment.
To examine the role flowering phenology plays in the reproduction of Echinacea angustifolia, Jennifer Ison planted experimental plot 2 (exPt 2) in 2006 with 3961 individuals selected for extreme (early or late) flowering timing, or phenology. In 2016, we monitored the start and end dates of flowering for the 570 flowering plants (933 heads) in the plot. The first head started shedding pollen on June 22 and the latest bloomer ended flowering on August 8th. Peak flowering was on July 7th, when 810 heads were flowering. Using the phenological data collected this summer, we will explore how flowering phenology influences reproductive fitness and estimate the heritability of flowering time in Echinacea angustifolia.
 Tracking phenology for 900+ heads in exPt2 was a big job. Here, three teams assess phenology on a nice day at exPt 2. Start year: 2006
Location: Experimental Plot 2, Hegg Lake WMA
Overlaps with: phenology in experimental plots, phenology in the remnants
Physical specimen: We harvested 870 heads from exPt 2. We were unable to harvest some heads which had been grazed by rodents. We brought the harvest back to the lab, where we will count fruits and assess seed set. Jennifer previously collected tissue samples from all individuals in the plot and plans to use these to genotype all of the individuals that flowered in 2016 this year and determine their parentage in exPt 1.
Data collected: We visit all plants with flowering heads every three days until they are done flowering to record start and end dates of flowering for all heads. We managed phenology data in R and added it to the full dataset.
Products: Will estimated heritability of flowering time using the data from 2015 and presented his findings this summer at ESA (see his poster here). He is continuing this work by assessing how heritability estimates differ between two years. He is comparing flowering in 2015 (a burn year) and 2016 (a non-burn year).
You can find more information about our experiment the heritability of flowering time and links to previous flog posts regarding this experiment at the background page for the experiment.
 One of many visits to each flowering plant in prairie remnants. Assessing fitness is a key part of understanding change in any population. The Echinacea Project has focused on two quantifiable components of reproductive fitness of Echinacea angustifolia: style persistence and seed set. Styles shrivel when they receive compatible pollen, and thus persistence of styles reflects pollen limitation. A floret sets a seeds only when it has been successfully pollinated. Together, these two indicators can be used to predict how effectively individual plants produce viable offspring, giving insights into the persistence of remnant populations.
This year, we counted shriveled and non-shriveled rows of styles on each flowering head of every plant in 28 remnants three times per week. Well after the flowering season, we harvested 104 heads at a subset of these sites. The harvested heads will have their achenes removed, counted, and x-rayed by citizen science volunteers to estimate how many seeds they produced. There were several concurrent projects this summer and in the lab that use these measures, including Amy Waananen’s compatibility study and James Eckhardt’s study of edge effects.
Year: 1996
Location: Roadsides, railroads and rights of way, and nature preserves in and near Solem Township, Minnesota.
Overlaps with: flowering phenology in remnants, mating compatability in remnants
Physical specimens: 104 harvested heads, currently at the Chicago Botanic Garden
Data collected:
- Style persistence data for each flowering head, collected three times per week, stored in remData
- Dates and identities of harvested heads, stored on paper datasheets in Harvest 2016 binder and entered electronically into remData
GPS Points Shot: A point for each flowering head, stored under PHEN and SURV records in GeospatialDataBackup
Products:
You can find out more about reproductive fitness in the remnants and read previous flog posts about it on the background page for the experiment.
An Echinacea seedling. Between the summers of 2007 and 2013, team Echinacea observed the recruitment of Echinacea angustifolia seedlings around focal plants at 13 different prairie remnants. The locations of these seedlings were mapped relative to each focal plant and the seedlings (now former seedlings) are revisited each year. For each of these former seedlings, we make a record each year updating its status (e.g., basal, not found), rosette count, and leaf lengths. We also try to update the maps, which are kept on paper and passed down through the years, and add toothpicks to note useful landmarks when searching. This summer, we checked 119 focal plants at 12 remnants for 239 former seedlings. We found 148 of these former seedlings (out of the original 955). Although challenging to obtain, this data on the early stages of E. angustifolia in remnants is valuable and rare for us, as nearly all of our data from the remnants comes from plants that have already flowered (several years after first establishing). This data can tell us, for example, how long it takes plants to flower, and the mortality rate among seedlings in remnants.
Year started: 2007
Location: East Elk Lake Road, East Riley, East of Town Hall, KJ’s, Loeffler’s Corner, Landfill, Nessman, Riley, Steven’s Aproach, South of Golf Course remnants and Staffanson Prairie Preserve.
Overlaps with: Demographic census in remnants
Data collected:
- Electronic records of status, leaf measurements, rosette count, and 12-cm neighbors for each seedling. Currently in Pendragon database
- Updated paper maps with status of searched-for plants and helpful landmarks
Products: Amy Dykstra used seedling survival data from 2010 and 2011 to model population growth rates as a part of her dissertation.
You can read more about the seedling establishment experiment and links to previous flog entries about the experiment on the background page for this experiment.
 Alex and Lea measure qGen3 seedlings with much enthusiasm. The main goal of the qGen2 and qGen3 experiments is to quantify the evolutionary potential of two remnant prairie populations of Echinacea angustifolia by estimating the additive genetic variance of fitness. We make estimates for two mating scenarios. The first scenario is an experimental crossing design with all matings among plants from two “core” sites: SPP and LF (core x core). The second design uses sires (pollen donors) from the core and dams from sites peripheral to the core. The crosses performed (core x core, core x periphery) in this experiment will quantify additive genetic variance for fitness in each site and each experimental group. Additionally, we will test for differentiation among families; do progeny from sires differ after accounting for maternal (dam) effects?
In 2016, we found 1724 two year old plants out of the 2581 locations where plants had previously been found for the qGen2 cohort and 644 seedlings in the qGen3 cohort.
Comparing germination between the qGen2 & qGen3 cohorts:
| exp |
approxFullAcheneCt |
totalAcheneCt |
seedlingCt |
germination |
| qGen2 |
6300 |
26144 |
2581 |
41% |
| qGen3 |
6200 |
19777 |
644 |
10% |
Our crossing success, measured by the proportion of full achenes to total achenes crossed, increased in qGen3 (31%) compared to qGen2 (24%). While we planted approximately the same number of full achenes in the qGen2 & qGen3 cohorts, the germination rate was 4 times greater in qGen2 (41%) compared to qGen3 (10%). This difference was likely due to differences in environmental conditions. The Spring of 2016, was quite dry and probably tough on Echinacea seeds and sprouts.
Start year qGen3: 2015
Start year qGen2: 2013
Location: exPt 1 (dams), remnants Landfill and Staffanson (sires), remnants Landfill (core) & around Landfill (peripheral) and remnants Staffanson (core) & railroad crossing sites (peripheral) (grand-dams), exPt 8 (progeny)
Overlaps with: Heritability of fitness–qGen1
Data collected: We used handheld computers to collect data on seedlings and juvenile plants.
You can find more information about Heritability of fitness–qGen2 & qGen3 and links to previous flog posts regarding this experiment at the background page for the experiment.
For the past three years, studying phenology in the remnants has been a major focus of our summer field work. The motivation behind this study is to understand how timing of flowering affects the reproductive opportunity and fitness of individuals in natural populations. Stuart began studying phenology in remnant populations between 1996 and 1999 and several students also studied certain populations in following years. From 2014-2016, we tracked phenology in all of our remnant populations. This year there were 1040 flowering plants (1500 flowering heads).
Flowering began on June 18th with one plant at the East Riley roadside remnant. Sadly, this early bloomer was mowed just 6 days after it started flowering. The latest flowering plant shed pollen in the West Unit of Staffanson Prairie Preserve on August 17th. When we consider all populations together, peak flowering was on July 10th. Peak flowering at Staffanson Prairie Preserve was later, on July 18th, likely due to the prescribed burn in the West Unit setting flowering back.
 Line segments represent the duration of flowering for each remnant population. Click to enlarge! As you can see in the figure above, some populations had much longer duration of flowering than others. Flowering duration at Staffanson Prairie Preserve (‘spp’ in the figure) was longer because the west unit was delayed in flowering. East Riley (‘eri’) has a long duration of flowering, likely due to individuals being mowed early in the season, then resprouting and flowering later. This figure shows the very first and last dates of flowering, but population mean start and end dates of flowering is also informative (see what that flowering schedule looks like here). These figure with generated with R package mateable, which was was developed by Team Echinacea to visualize and analyze phenology data.
Start year: 1996
Location: roadsides, railroad rights of way, and nature preserves in and near Solem Township, MN
Overlaps with: Phenology in experimental plots, demography in the remnants
Physical specimens:
- We harvested a random sample of 5 heads from most remnant populations (we excluded very small populations) and brought them back to the lab, where student interns will process and assess their seed set (‘regRem’ or ‘regular remnant harvest’).
- We also harvested the most isolated, least isolated, earliest flowering, and latest flowering individuals from large populations (‘remnant extremes’). Student interns will also process and assess seed set of these heads.
Data collected: We identify each plant with a numbered tag affixed to the stem and give each head a differently colored twist tie, so that each head has a unique tag/twist-tie combination, or “head ID”, under which we store all phenology data. We monitor the flowering status of all flowering plants in the remnants, visiting at least once every three days until all heads were done flowering to obtain start and end dates of flowering. We managed the data in the R project ‘aiisummer2016′ and will add it to the database of previous years’ remnant phenology records.
GPS points shot: We shot GPS points at all of the plants we monitored except for four, two at SGC and two at ERI, which were mowed (ERI) or dug up (SGC) early in the season. These points were shot under job names following the convention “SURV_2016MMDD_SULU” or “SURV_2016MMDD_CHEK”. The locations of plants this year will be aligned with previously recorded locations, and each will be given an identifier (‘AKA’). We will link this year’s phenology and survey records via the headID to AKA table.
You can find more information about phenology in the remnants and links to previous flog posts regarding this experiment at the background page for the experiment.
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