We have a patch of an invasive weed in our main experimental plot. We have been trying to keep this non-native hawkweed from spreading for several years. This year we did a really good job. First, we found all the satellite patches and used the opportunity to practice reading and making maps. Then we pulled all the flowers stems–we estimated 369 stems. Here’s a map of all hawkweed patches and the main infestations is the 10m x 10m square.
Then we pulled all the stems in the square of infestation, counting as we pulled. Here are the counts & the total in the square:
After we counted and pulled, we each made an independent estimate of the number of flowering stems we missed. We could have missed stems that were trampled or difficult to see with the current light conditions. Here are our counts with the mean and median:
Stuart went back when it was cloudy and found 47 stems in the infestation square, mostly trampled. The next day he systematically walked the square and found 4 more. So that’s 51 missed. One person had a pretty close estimate (48). All but one of our estimates were optimistic about our thoroughness.
round(c(37,51)/(1265+51), 3) [1] 0.028 0.039
We estimated a miss rate of 3% and our actual rate was closer to 4%. We practiced estimating, pulled a lot of stems, ~1700, and have maps to go back and get the plants later this season. Good work, team!
Today begins the field season! We had many activities planned to get everyone off to a good start for a productive and learning-filled summer.
introductions
safety training
getting gear
visiting sites
lunch
mapping orientation
directed observations & flogging
scheduling rest of week
We wrapped up with watermelon and a group photo:
First row: Ning, Hailey, Abby, Liam. 2nd row: Emma, Jared, Ian, Wyatt, Maddie, Brittany. Not pictured: Zach & Elise will start next week because their schools run late. Ruth will come up Thursday or Friday. Stuart took the photo.
Chicago Botanic Garden volunteer and community scientist Allen Wagner just counted his 1,500,001st Echinacea fruit today. Allen counts fruits of plants from science projects that shed light on pollination of purple coneflowers in experimental plots and in natural prairies. Allen has collected data for the Echinacea Project research initiative since 2017 to help us learn about the effects of prescribed fire on plant reproduction and about the magnitude of inbreeding depression in fragmented prairie populations.
Thank you Allen for your dedicated service to the Echinacea project, to advancing science, and to the conservation of prairie habitat!
Alan has been a volunteer at the Chicago Botanic Garden for 19 years and has been working on the Echinacea project in the plant reproductive biology lab at the Chicago at the plant conservation sign center since 2017. For his dedication, and speediness, Allen has been invested as the Count of Achene County and CEO of Echinacea Inc. What’s next… President of the Echi-nation?
NB. ‘Achene’ /uh-keen/ is the technical term for an Echinacea fruit.
For our seed addition experiment, we want to know exactly how many seeds we planted in each 1 m transect. Each transect got seeds from one envelope. Before planting, we took xrays of the fruits in the paper envelopes. With minimal processing, the radiographs look good! We have a batch of 251 images to classify. This sounds like a job for Allen Wagner aka “the Count” (of Achene County).
Radiograph of Echinacea fruits in envelope 105.3a /230. Other partial envelopes are visible on the margins.
We used the column blower and other techniques to remove empty fruits. We aimed for about 50 seeds per envelope. How many do you count?
Good grief! As if regular old atmospheric inclement weather wasn’t enough to worry about, now we can worry about inclement ionospheric weather too! The fire season appears to be coming early and strong, which may make it difficult to conduct prescribed burns and work outdoors. The upcoming solar maximum appears to be coming early and strong, which makes it difficult to use our precision GPS machines, which are essential to our fieldwork.
Here’s a MnDOT bulletin from today warning us to expect bad performance of gps due to space weather rocking the satellites.
Network Ionosphere Unreliability Issues – a bulletin from MnCORS Minnesota Department of Transportation on 03/06/2024
In the lab today we were talking about Fibonacci numbers. Somehow these numbers (1, 1, 2, 3, 5, 8, 13, 21, 34, …) relate to Echinacea flowerheads. The number of ray florets (aka “petals”) on ab Echinacea head are often Finbonacci numbers, like 13 & 21, but they are often not those numbers. This Wikipedia page describes the relationship between Fibonacci series and florets on flowerheads.
Here are some images of Echinacea heads from the summer (top views). Do you see any interesting patterns?
Top view of head of Echinacea angustifolia. How may ray florets? Click image to enlarge to see pattern of disk florets.Head of Echinacea angustifolia with two beesTwo heads of Echinacea pallida. This species is not native to Minnesota, but it was planted by accident in a prairie restoration in our study areabeetle on head of Echinacea angustifolia
There are many reasons we don’t want to lose prairie remnants to woody encroachment or conversion to agriculture. One of them is because we don’t want the Carbon in the soil to go to the atmosphere. Here’s a nice visual derived from IPCC data, 2022.
Many plants, including Echinacea angustifolia, flower vigorously during the summer after a prescribed burn. We’ve demonstrated that the benefits of fire for seed production, in many circumstances, are bigger than just the increase in flowering. The additional boost to seed production results from better pollination after fires compared to other times. Now we are trying to figure out what’s going on with pollination–why is it better after a fire? It might be related to pollen or nectar, which are foods for the bees that pollinate Echinacea. Here are two possibilities: 1) after a fire, plants produce more or better pollen or nectar which draws in bees from farther away, so the plants get more visits and better pollination, presumably the bees are happier with abundant & healthy food. 2) after a fire, plants produce less or lower quality pollen or nectar which means bees need to fly to more plants to get a decent meal, so the plants get more visits, and the bees are probably frustrated with skimpier meals and bad food. The third possibility is that plants produce the same quality and quantity of pollen & nectar regardless of fires.
Over the summer we systematically collected pollen and nectar from many Echinacea plants in many populations (19) over many days. Our goal is to evaluate how fires affects the quality and quantity of pollen & nectar produced by Echinacea plants. We are getting close to wrapping up data-entry for our field collection of pollen and nectar from Echinacea angustifolia. Here’s a summary of data-entry progress so far…
Each “tagCt” is the number of Echinacea plants we sampled at each site. We will keep you posted!
Funding for this project was provided by the Minnesota Environment and Natural Resources Trust Fund as recommended by the Legislative-Citizen Commission on Minnesota Resources (LCCMR).
