Joanna Weremijewicz

Over the last century of plant research, whether plant interactions will be competitive, neutral, or facilitative has remained elusive.  This enigma may persist because most investigations have failed to consider the role of ubiquitous common mycorrhizal networks formed by symbiotic arbuscular mycorrhizal fungi.  

Arbuscular mycorrhizal fungi are symbiotic, root inhabiting fungi, that associate with the majority of plants in the world today. Consequently, arbuscular mycorrhizal fungi can interconnect plants when hyphae from one root system forage for mineral nutrients throughout the soil, then encounter and colonize the roots of another plant, forming a common mycorrhizal network.

To understand how these fungi contribute to plants’ competitive abilities and consequent species dominance, my research investigates the influence of common mycorrhizal networks on plant mineral nutrition, plant interactions, and nutrient movement. Recently, I obtained a $714,000 National Science Foundation Faculty Early Career Development Program (CAREER) grant to investigate how the U.S.'s worst weed, Canada Thistle (Cirsium arvense) may use this symbiosis and the consequent networks to establish, change, and persist in new areas. This work has supported and involved 21 undergraduates and 3 high school students in ecological research since the summer of 2022.

A second research interest of mine is in the science of teaching.  I am interested in the role of course-based research experiences in student achievement, retention within STEM (Science, Technology, Engineering, and Math) fields, and interest in pursuing extracurricular research experiences.   I am particularly interested in how course-based research experiences may influence students from underrepresented minority or first-generation backgrounds. The biology department currently runs a research course on the West Nile Virus as it's introductory biology course, and we are investigating it's impact on student learning and retention. 

And finally, I have a vested interest in working with, advising, and supporting students from first-generation and transfer backgrounds. I am the co-PI on a National Science Foundation Scholarships in STEM (NSF S-STEM) grant that provides $10,000 annual scholarships and programming for high-ability, low-income students. The program is called the Leadership Experience and Advancement Program in STEM (LEAPS) and I assist with running this program as well as mentoring biology LEAPS Scholars. I am also the First-gen Cardinals Biology faculty mentor. 

Selected Scholarship

Russell, M.*, Řezáčová, V., Miller K.S.*, Nardi, W.H.*, Brown, M.*, Weremijewicz, J. (2025) Common Mycorrhizal Networks Improve Survival and Mediate Facilitative Plant Interactions of Andropogon gerardii Seedlings Under Drought Stress. Mycorrhiza. 35(1) 1-8

*North Central College student authors

Řezáčová, V., Weremijewicz, J., Michalová, T. (2024) A non-native weed, E. sphaerocephalus, alters carbon and phosphorus dynamics between native plants and a common mycorrhizal network. Functional Ecology. 39(2), 418-431

Indorf, J. L.*, Weremijewicz, J.*, Janos, D.P., Gaines, M.S. (2019). Adding Authenticity to Inquiry in a First-Year, Research-Based, Biology Laboratory Course. CBE—Life Sciences Education 18(3): ar38.

* these authors contributed equally to the work

Weremijewicz, J., & Janos, D. P. (2019). Investigation of Plant Interactions Across Common Mycorrhizal Networks Using Rotated Cores. JoVE (Journal of Visualized Experiments), (145), e59338.

Weremijewicz, J., Sternberg L da SL, Janos, D.P. (2016) Common mycorrhizal networks amplify competition by preferential mineral nutrient allocation to large host plants. New Phytologist. 212(2): 461-471.doi10.1111/nph.14041

Courses Taught

Plant Interactions in a Changing World (BIOL325)

Plant Growth and Function (BIOL320)

Ecology Laboratory (BIO250)

BIOL390 Careers in Biological Science

Exploring Biology (BIOL205)

Investigating Biology (BIOL195)

Introduction to Environmental Science (BIOL/ENVI 106)