research team mentor
Principal Investigator
Anna Wassel, BS (Environmental Science, Emory University)
PhD candidate, Ecology and Evolutionary Biology program
Washington University in St. Louis
Email: a.c.wassel@wustl.edu
Research focus for summer 2024
Our team researches how a funny native tree species affects the understory plant community! Pawpaw (Asimina triloba) is a locally dominant midstory shrub, meaning it is both highly abundant, and has a big impact on diversity. We call it “locally” dominant because it is not highly abundant all through the forest, but in areas where it is present, there are many, many stems making up dense clonal patches. This allows us to study the impact of this species presence and absence pretty clearly since the edges of these patches are easy to see and define.
In past years we discovered that understory herbaceous plants are less diverse and also less abundant (meaning fewer individuals overall) in the presence of pawpaws. This summer, we aim to figure out at what stage of the recruitment process this is happening: dispersal, germination, survival to adulthood, or reproduction. We planted seeds of three target species in plots inside and outside pawpaw patches to be monitored for growth, survival, and reproduction. Knowing at what stage of recruitment pawpaws most affect the understory could have important conservation implications.
Skills
techniques
methods
Plant identification:
You will learn how to identify both woody and herbaceous (not woody) plant species mostly based on vegetative characteristics (that is: without using the flowering part of the plant). You will be trained on some basic botanical terminology, and how to use iNaturalist as an aid.
Data collection and entry:
Collecting data in the field has special challenges (but also special rewards). You will learn how to survey plant communities and keep data and notes accurate and organized. You may also have the opportunity to practice data entry and basic analysis in Excel and R.
research conditions
We will spend at least 80% of the time out in the field (the forest, to be exact)! While there will be mosquitoes, ticks, spiders, snakes (sometimes venomous), hot temperatures, and walking up and down steep, rocky hillsides, this much time outdoors also means the best opportunities for seeing more fun nature things like orchids, fungi, frogs, armadillos, and cool rocks. You will be guided on best practices in the field to ensure a safe and fun field season!
Team structure and opportunities for independent research
You will work directly with fifth-year graduate student Anna Wassel. Day-to-day, you will work with at least one teammate on data collection and other tasks; good teamwork skills and clear, honest, kind communication is a must. Our team will also include high school TERA participants.
Anna is part of Jonathan Myers’ forest dynamics lab at Washington University in St Louis. There will be some opportunities to work with the Forest Team on seed sorting and tree ID. Occasional joint lab meetings may also be an option depending on the needs and wants of the students.
There will be opportunities to conduct independent research related to pawpaw biology and ecology, or community ecology more generally. Students may have an opportunity to collect new data or to analyze existing data in a new way. Past projects have included observational studies and data analysis such as: investigating rates of mortality and regeneration of stems in a pawpaw patch, bird diversity inside and outside pawpaw patches, and the effect on understory communities when pawpaws and invasive bush honeysuckle co-occur.