Our lab has collaborated with numerous scientists while working across the Pumice Plain of Mount St. Helens. We have had the honor of working with USFS Ecologists Shannon Claeson and Charlie Crisafulli! Shannon is an aquatic entomologist and has co-led the stream surveys across the Pumice Plain since 2015.
USFS Ecologist Charlie Crisafulli has worked on Mount St. Helens since the eruption and helps us understand the willow stem boring weevil Cryptorhynchus lapathi. Photo by Carri LeRoy
Charlie Crisafulli has worked on Mount St Helens since the eruption in 1980 studying the initial and long-term responses of communities and ecosystems to large disturbances. A portion of his work focuses on the nonnative stem-boring weevil colonization and its influences on plant succession!
USFS Ecologist Shannon Claeson has collaborated on stream surveys at Mount St. Helens since 2015, but has worked on the mountain for over 10 years. Photo by Carri LeRoy
In working with Shannon and Charlie, our team members have been able to learn more about stream evolution across the Pumice Plain as well as the stem-boring weevil and its influences on MSH willows. In fact, our team has even identified that weevils prefer female over male willows across the Pumice Plain!
Our National Science Foundation (NSF) grant provided funding for two full field seasons at Mount St. Helens. In the first year, we collected a dataset comparing the colonization patterns of willow males and females on the Pumice Plain and published a paper in Ecosphere with four undergraduate co-authors (LeRoy et al. 2020)!
One of the first papers to be published from our work at Mount St. Helens. Four co-authors are undergraduates at The Evergreen State College. (LeRoy et al. 2020, Ecosphere)
Several figures from the paper showing male-female willow differences in initial leaf chemistry and chemistry throughout the decomposition process. (LeRoy et al. 2020, Ecosphere)
We found that the leaf chemistry of male and female willows differs, where males have significantly higher nitrogen and females have higher C:N ratios (LeRoy et al. 2020). These patterns persist through time in the stream, providing in-stream invertebrates with variation in food resources.
Getting started on data analysis and paper writing around the fire at our field camp at Mount St. Helens in summer of 2018! Photo by Shannon Claeson
On long field trips, we get right to work analyzing data in the field. Our team consists of Evergreen faculty, Forest Service collaborators, and lots of invaluable undergraduate research assistants. Nothing better than data-analysis by the fire-side!
Our study made the cover of the issue in Ecosphere. This is a drone photo taken with a permit of willow colonization on the Pumice Plain. Photo by Carri LeRoy (Mavic 2 Pro)
Some of our research involves using drone technology to explore willow colonization patterns. We were asked to contribute cover photos to the journal Ecosphere and one of our drone images made the cover! Follow along to learn more about the awesome, NSF funded work, collaborative student-faculty research on aquatic-terrestrial interactions in early successional headwater streams of Mount St. Helens!
Healthy willow growth alongside a young stream at Mount St. Helens. Photo by Carri LeRoy
Willows, Salix species, are a common riparian plant across the globe and are a key early successional species. Willows are known to increase water quality and stabilize banks, so it is not hard to believe they are a dominant riparian plant on the Pumice Plain of Mount St. Helens.
Willows on the Pumice Plain (Salix sitchensis) are dioecious – meaning they have male and female individuals. Here you can see them tagged with blue and pink flagging. Photo by Carri LeRoy
Willows are a dioecious species (they have both male and female individual shrubs) that play a vital role in understanding ecological interactions across the Pumice Plain. Our lab has documented plant sex ratios, colonization locations, and chemical differences among willow populations to understand primary succession.
Female Sitka willow need to produce costly flowers and fruits. This might be one reason they colonize closer to streamsides. Photo by Angie Froedin-Morgensen
Interestingly, a high proportion of riparian plants are dioecious. We are working to understand what advantages there are to having male and female separation along streamsides in particular. In our system, females colonize closer to streams – maybe higher resource availability for producing flowers? Stay tuned for tomorrow’s post about our latest paper regarding willow sex differences at Mount St. Helens!
Prepped samples of ground leaves (left) and tannin samples mid-extraction process (right). Photos by Iris Garthwaite
Across the Pumice Plain of Mount St. Helens, Sitka willows (Salix sitchensis) make up a major percentage of the riparian (streamside) vegetation. Parts of our research focuses on identifying phenolic compounds called condensed tannins within willow leaves!
Evergreen undergraduates, Lauren Thompson (left) and Maddie Thompson (right) running the condensed tannin extraction and assay. Photo by Iris Garthwaite
Condensed tannins of willow leaves may act as anti-herbivore compounds and make willow leaves less palatable based on their concentrations. The processes of condensed tannin extraction and assay are very long but filled with numerous colorful steps!
The colorimetric condensed tannin assay results in an awesome gradient of pink! Photo by Madeline Thompson
Phenolic compounds may differ across the Pumice Plain or by plant sex (willow is dioecious!). Leaf chemistry can influence which insects utilize the leaves and rates of decomposition for leaf litter!
Litterbag showing willow leaf litter and a unique metal tag for identification!
Across the Pumice Plain, willow leaf litter bags are placed into streams to conduct a variety of assays. After the leaves are colonized by bacteria and fungi and begin to decompose, we remove the leaves and use DNA extractions to identify microbial communities!
Various stages in the DNA extraction process: Macerated leaf material, intermediate stages of DNA extraction, and final extracts for analysis. Photos by Lauren Thompson
The DNA extraction process entails numerous lengthy, yet exciting steps. Whether its shaking samples up vigorously with a vortexer or lysing cell matter with solutions, Evergreen Undergraduates Lauren and Maddie Thompson are always up for the challenge!
Undergraduate Maddie Thompson testing for DNA concentrations on the nanodrop! Photo by Lauren Thompson
Extracted DNA from willow samples is then sent off to characterize microbes present! This identifies what microbes colonize first, starts decomposition, provides nutrients to aquatic macroinvertebrates, and may be influenced by the sex of willows!
Chrysomelid beetle larvae chew on willow leaves – leaving these patterns of skeletonization behind. Photo by Carri LeRoy
Willows across the Pumice Plain of Mount St. Helens provide more than just riparian vegetation! They provide shelter, habitat and food to a variety of insects. Insects like Chrysomelid beetle larvae chew their way through willow leaves!
The poplar & willow stem-boring weevil, Cryptorhynchus lapathi, was introduced to Mount St. Helens in 1989. Photo by Carri LeRoy
Another insect that utilizes the willows is the stem-boring weevil, which is native to Europe but was introduced to Mount St Helens in 1989! The tiny long-nosed guys, show up a lot in our studies as they cause branch death and mortality of willows.
Galling herbivores like this likely galling midge show variation in activity across the Pumice Plain of Mount St. Helens. Photo by Carri LeRoy
Insects like galling midges have specialized feeding behaviors that require willow leaves as a host. They create new microhabitats for their young via galling. Stay tuned to learn more about the aquatic macroinvertebrates that colonize willow leaves that fall into streams!
Iris helping to tag Sitka willows as male or female (pink!) along Clear Creek at Mount St. Helens in summer 2019. Photo by Carri LeRoy
“It’s unconventional, but I view ecological studies as a radical form of generous listening to the world around us. My current listening project (research) investigates the temporal dynamics of multitrophic interactions in aquatic-terrestrial ecosystems.”
“I am currently studying interactions between Salixsitchensis phenology, phytochemistry and stream biota at MSH. Advancing our understanding in this research area allows for better predictions of climate -driven ecological mismatch in land-water ecosystems.”
Iris helped coordinate science outreach for the Mount St. Helens Institute’s GeoGirls program in the summer of 2019. Here she is leading a pack of 25 middle school girls. Photo by Carri LeRoy
“Research at MSH with Dr. LeRoy has allowed me to:
Participate in NSF- funded research
Conduct independent stream ecology research
Co-author a peer-reviewed publication
Form strong relationships with peers and mentors
And so much more!”
“I am passionate about supporting other #WomenInSTEM and connecting youth with nature. I have such a supportive group in the L3 lab and I want to give others that same feeling of comfort with science and the natural world.”
Iris and fellow undergraduate Victoria Cowan enjoying some shade on the blistering Pumice Plain of Mount St. Helens in the summer of 2019. Photo by Carri LeRoy
“I am so excited to have two manuscripts in progress as an undergraduate. The sky is the limit for research opportunities at Evergreen. I am looking forward to publishing our research and sharing our work with the broader freshwater ecology community.”
“Research is an art form of listening, sometimes it is with a hyporheic well, an extraction, a pH meter, a mass spectra or simply sitting by the stream. Evergreen is my academic home, it understands my way of listening and my desire not to push my way into an answer but to find patterns and relationships in a landscape of uncertainty and null hypotheses.”
Iris and fellow field assistants taking a much needed rest in the shade of willows and alders at Mount St Helens, summer 2019. Photo by Carri LeRoy
“Instead of starting with the question- what do I want to discover? I like to enter a new study system with “what wants to be discovered?” I come from a background in permaculture, where we are taught to watch the land for quite some time before jumping in and making changes. Where does the shade hit in November? What family of plants sprout in February? Where does rain collect in December? That’s the kind of science I like to do- meaningful, thoughtful and full of listening.”
Litter bags filled with willow leaves and flowers prepped for deployment and deployed in streams at Mount St. Helens. Photos by Carri LeRoy
Litter bags filled with willow leaves and flowers for undergraduate Iris Garthwaite’s independent research project as part of the Summer Undergraduate Research Fellowship (SURF) program. We use metal ID tags to track willow identity, plant sex, and weevil attack status.
Willow leaves incubated in the streams of the Pumice Plain decompose and skeletonize over time. Photo by Carri LeRoy
Litter bags installed in streams help us determine decomposition and organic matter cycling rates. Willow leaves and flowers are colonized by microbes and aquatic macroinvertebrates that eat microbes and shred leaves. SURF student Angie Froedin-Morgensen focuses on invert ID.
Our research truck turned solar-powered drying oven – our solution to drying leaves at a remote field site! Photo by Carri LeRoy.
The whole crew gets involved when it’s time for peak leaf fall! Our studies are often limited by how much leaf litter we can catch at abscission. On multi-day trips, we get creative about drying leaves – we converted our research truck into a solar-powered drying oven!
The Leaf Litter Lab had the honor of presenting a small glimpse into each individual scopes of research to Christine Hoffmann, who works for the Public Relations Outreach here at Evergreen.
With focuses on the National Science Foundation-funded ecology research of Mount St. Helen’s, undergraduates have been able to take on multiple approaches to conduct individual research projects.
Iris Garthwaite is a Senior who takes on both a peer-mentor and leadership role. She’s conducted an entire project around willow catkin and aquatic invertebrate interactions to investigate flowers as detrital resource for stream ecosystems. With the end of her research project she has been working hard at picking a graduate school and writing her first first-author paper!
Brandy speaking about the Norman H. Anderson macro-invertebrate samples.
Brandy Kamakawiwoole is a Junior working on aquatic macro-invertebrate sorting, stream GIF imaging, and analyzing historical BMI records. The historical records are from the 1981-1982 Norman H. Anderson Collection Samples, making them the first aquatic macro-invertebrate samples collected following the eruption of Mount St. Helens!
Angie Frödin-Morgensen is a Senior who has an interest in freshwater ecology. She spends most her time working hard at a microscope sorting through leaf litter to identify aquatic macro-invertebrates. Her research focuses on macro-invertebrate community differences between female and male Sitka willow leaf litter!
Angie discussing the important roles of macro-invertebrates as bio-indicators of streams.
Maddie Thompson is a Junior with interest in environment studies and ecology. She’s been continuing the research on canopy covering influencing in-stream ecosystem function. She also takes part in her research project that focuses on Willow DNA extractions to identify microbial communities.
Lauren Thompson is a Junior studying ecology and environmental studies. She’s continuing the research on how environmental conditions influence organic matter processing across Mount St. Helens watersheds. She works jointly with Maddie in assessing condensed tannin’s and Willow DNA extractions.
Stay tuned… Iris, Angie, Maddie and Lauren plan to attend and present at the 2020 Society for Freshwater Science Annual Meeting!
