Big project update! For my summer project I am looking at nectar and pollen volumes in other Asteraceae plants that are non – Echinacea in burned sites versus unburned sites. This is important because pollinators depend on pollen and nectar to get the nutrients they need. A large decrease in pollinators has been found due to prairie fragmentation, and studying whether fire can help in producing a higher quantity of pollen and nectar can be shared with land managers to help create more viable resources for pollinators in their prairie restoration efforts. My two species of focus for now are Coreopsis palmata (also known as prairie coreopsis) and Helianthus pauciflorus (also known as stiff sunflower). Mid-summer coreopsis blooming is starting to come to close and so are my nectar and pollen measurements! Onto sunflowers here in the next couple weeks!
Time for daily update: Total demo continues! One group of 4 and one group of 3 went out to a total of 4 different sites. These included south of golf course, north of golf course, and yellow orchid hill east and west. A few people also finished up or pollen and nectar collection on Echinacea heads.
This afternoon a group went out and did e-trap collection and retrieval. We have been working on rotation 5 this week after finally polishing off rotation 4 late last week! The rest of us went and did measurements of Echinacea in one of our experimental plots (P9). Measurements included: flowering rosette count, basal rosette count, total basal leaves, height of tallest basal leaf, height of tallest cauline leaf (aka leaf on stem without a petiole), and height of head to name a few. Our plant of the day was finding a diseased Echinacea with over 360 basal leaves. To finish off the day we moved the goats to a new paddock and enjoyed some cold watermelon in the late week heat.
Today Team Echinacea continued to wrap up the pollen and nectar collection. Only a few focal plants are still in flower. Another group worked on flagging and recording demographic information for every flowering Echinacea plant in every remnant site. Some of these plants have tags dating back decades! In the experimental plots, Stuart trained team members to find and measure all Echinacea. This data will help us understand performance of E. angustifolia x pallida hybrids. Round 5 of emergence trapping started recently. The team members are now pros at deploying and retrieving the traps.
This morning the whole team got together to pull as much sweet clover as we could from p01. After the drippy morning faded, we split up to collect pollen from Echinacea angustifolia at sites throughout the area. This is part of an MN ENRTF funded project to help determine the impacts of prescribed burns on pollen and nectar quantity and quality in echinacea. After lunch, some people went to retrieve and deploy emergence traps and the rest of us went to collect nectar from echinacea plants. To collect the nectar, we are using tiny glass microcap tubes carefully inserted into the florets. Overall, we had a productive day, and enjoyed the nice weather after a wet 4th!
The beginning of flowering for Echinacea angustifolia means it’s time for Team Echinacea to get collect Echinacea pollen and nectar! This project is part of our MN ENRTF funded research to understand fire’s impacts on ground nesting bee habitat and food resources. It’s our second year of sampling and we have made some modifications and improvements to our protocol.
This year we are collecting from a total of 62 plants across 12 sites (some burned in 2023, some in 2024, and a few not burned in either year). Where possible, we are collecting from plants that we also collected from last year, which will make for some interesting comparisons. Many plants did not re-flower in 2024, so Wyatt and I bolstered our sample by randomly selecting other focal plants.
On Monday, Wyatt and I visited our first flowering focal plants with Grace and Rebecca from NDSU and tested out methods. We learned how to sample immature florets, a new method we are using to assess pollen quantity this year. We also brushed up on nectar and pollen collection.
Wyatt collects pollen from the anthers of a flowering Echinacea
By Tuesday we were able to train the whole team in on the protocol and start collecting! So far our data sheets have worked pretty well, and we are figuring out ways to improve efficiency in the field. Stay tuned as more of our focal plants begin to flower!
Today we welcomed goats to Hjelm. They are already hard at work eating their way through the foliage. Keep up the good work, goats! Most of the humans worked on finishing searching for Stipa in p01 and started planting a new production garden to generate seed to add to the experimental plots. Ian and Liam valiantly continued staking points for the pollinator emergence study. Wyatt and Abby are getting ready to begin a study investigating the effects of fire on pollen and nectar production in Echinacea angustifolia. This project has many excellent collaborators and is part of the MN ENTRF funded research on prescribed fire and ground nesting bees.
We’re interested in investigating what resources are available to Echinacea visitors and learning more about the pollen and nectar Echinacea produces. We hope to learn if the nutritional resources available differ before and after burns. In 2022, Britney House developed methods for collecting nectar from Echinacea using microcapillary tubes. Read more about her methods here.
During the summer of 2023, the team collected pollen and nectar samples from Echinacea angustifolia at 19 sites in and around Solem Township, MN (plants at Hegg Lake were Echinacea pallida). We searched for and shot the ~20 plants (or, if few were available, as many as we could find) at each site that were closest to a random point. We then selected ten of those plants to bag up to three of their heads with pollinator exclusion bags. Throughout the duration of their flowering, we collected pollen from all bagged plants and nectar from five of them per site.
Stuart collects nectar from an Echinacea head
Midway through the experiment (mid-July), we removed bags from some of the pollen only plants to adjust our sample size to only the five pollen/nectar plants plus two backups per site. We removed bags from pollen/nectar plants and backup plants when they were done flowering, we’d collected a cumulative 50 mm of nectar from them, or we had received less than 15 mm of nectar from the plant in the last three visits (the latter was more of a guideline than a rule, used to save time by eliminating plants that were unlikely to provide us with enough nectar for analysis). At the Hegg pallida restoration, any heads that were not originally bagged were decapitated, and all heads were decapitated upon the final removal of their bags.
Following some experimentation, we conducted nectar collection only in the afternoons, while pollen collection could be done any time of day. In total, we collected 856 vials of pollen and 580 vials of nectar from 104 plants. These were given to Rahul Roy and Margaret Medini at St. Catherine University in St. Paul, who will be doing data analysis.
Data entry for collection datasheets is complete, and verified csvs for each site can be found at: Dropbox/teamEchinacea2023/z.pollenNectarDataEntry/coreVerified. Scans can be found at: Dropbox/teamEchinacea2023/z.pollenNectarDataEntry/scans.
Start year: 2023
Location: Various prairie remnants and one restoration (Hegg Pallida) around Solem Township, MN