Principal Investigator


Arjan Meddens

  • Arjan Meddens received his BS and MS at Wageningen University in The Netherlands before moving to Moscow, ID where he received his PhD from the University of Idaho in 2012. He started as an assistant professor at WSU in summer 2019.
  • Arjan’s Resume/CV
  • Email:

Current Members


Madeline Franz (PhD student)

Madeline joined the lab in 2020 after completing her MSc at Queen Mary, University of London. Her research focuses on the post-fire regeneration of forests and the use of remotely sensed data for vegetation classification and measurement. A native of Farming, MN, Madeline is still in awe of the mountains and takes to the hills whenever she can. She enjoys backpacking, canoeing, and gardening.

Okikiola Michael Alegbeleye (PhD student)

Okikiola is originally from Nigeria, and he joined the lab in fall 2023 to pursue his doctoral degree. He had his B. Forestry from the University of Ibadan, Nigeria and M.Sc. (Forest Biometrics and Remote Sensing) from Mississippi State University. His research focuses on the application of remote sensing, machine/deep learning and advanced statistical methodologies in proffering answers to ecological questions. He enjoys drawing/painting, playing keyboard, and sometimes writes poems.

Severin Scott

Severin Scott (PhD student)

Severin joined the lab in fall of 2023 after working for an environmental non-profit in Pittsburgh. Prior to that he completed a BS and BA at the University of Pittsburgh, and a MS at Columbia University. HIs research interests lie at the intersection of landscape ecology, climate change, and communities of practice. In his free time, Severin enjoys outdoor recreation, photography, and cooking

Yetunde Rotimi (PhD student)

Yetunde is from Nigeria where she earned her bachelor’s degree in the field of Forestry and Wildlife Management (University of Ilorin). She also holds a masters degree in Ecology and Conservation from Western Colorado University. Yetunde is currently affiliated with both the Riverine Ecology Lab and the Forest Ecosystem Dynamics Lab. Her research is focused on identifying Other Effective Area Conservation Measures (OECMS) and mapping ecosystem services using remote sensing. She enjoys cooking and watching movies.

Mason Mahacek (MS student)

Mason joined the lab in 2023 after graduating from the University of Michigan with a Bachelors of Science in Environmental Science (Wildlife Ecology specialization) . While at WSU he plans to study Wildfire Refugia in hopes of influencing future management practices. He is an avid outdoorsman and spends his free time fly fishing and hunting.

Robbie Andrus (Postdoc)

Robbie, originally from Chimacum, WA, studies forest disturbances (bark beetles, fire) and the implications of climate change for forests. He received his Ph.D. from University of Colorado in 2019 where his research focused on forest recovery following disturbances and climate effects on forest demography in subalpine forests. He enjoys fly fishing, backcountry skiing, and mountain biking.

Amanda Stahl (Postdoc)

Amanda received her PhD in Environmental & Natural Resource Sciences at Washington State University in Summer 2020 with a research focus on riparian (streamside) ecology and conservation. She is interested in developing innovative vegetation monitoring strategies using drone and satellite imagery and joined the Meddens lab in August 2020 to study forest disturbances. She enjoys backpacking, kayaking, and gardening. (Photo credit: Tom Schierman)

Joe Celebrezze (Research technician)

Joe was born and raised in Moscow, ID and moved to Wenatchee, WA in 8th grade before attending University of California, Santa Barbara (UCSB) and receiving his BS in Biological Sciences in Summer 2022. He is interested in disturbances (e.g., wildfire and insect outbreaks), resulting plant and forest mortality, and investigating ecosystems from the leaf-level to the landscape-level. He enjoys soccer, cooking, and birdwatching.

Past Members

Luke Schefke (MS student)

Luke received his MS from WSU in 2023 studying patterns of tree mortality from insect damage. Before that, he graduated from the University of Washington in 2020 with a Bachelor of Science in Biology and Earth & Space Sciences. He enjoys baking and hiking (and has been to multiple national parks).


Ivy Woltering (Undergraduate researcher)

Ivy grew up right here in Pullman, WA before pursuing a BS in Earth & Environmental Science at WSU, where she graduated in May 2022. She worked as an undergraduate research intern for the Meddens lab from summer 2021 – 2022, helping to gather field data and study post-wildfire forest regeneration through satellite remote sensing. She enjoys native species gardening, spending time in nature, and asking (seemingly endless) questions about plant identification.

Sarah Federle (right, Undergraduate researcher)

Sarah is originally from Soldotna, Alaska, where she spent her free time outdoors. This translated into the pursuit of a BS in Forestry and a minor in Geographic Information Systems (GIS) at WSU. She worked as an intern for the Meddens lab primarily performing drone imagery analysis studying post-wildfire forest regeneration. In her free time, she enjoys playing video games, spending time outdoors, and riding horses.

Aaron Wold (MS student)

Aaron is from the Tall Grass Prairie of Kansas. He moved to Washington in 2014 where he has been learning and recreating ever since. Aaron joined the Meddens lab as a masters student in the spring of 2020 and is studying the effects of drought on rangelands, while maintaining an interest in wildfires. Aaron is currently working as a Range Planner at the Okanogan Conservation District.

Paige Byassee doing field work at Rock Creek Ranch

Paige Byassee (Research technician)

Paige earned a B.S. in Ecology and a certificate in Geographic Information Systems from Appalachian State University and worked as a Reserach Technician from 2019 – 2020 for the Meddens Lab. She explores spatial analysis methodologies for monitoring forest health. She enjoys rock climbing, mountain biking, and working in the field.

Photo of Jasper Steenvoorden

Jasper Steenvoorden (MS student)

Jasper earned an MS at the University of Idaho with Dr. Meddens—completing a a thesis on the importance of fire refugia for the persistence of Greater sage-grouse in southeastern Oregon, which was recently published in the journal: Ecology & Evolution. Jasper now works as a teacher for the undergraduate Future Planet Studies program at the University of Amsterdam, which focuses on grand sustainability challenges, such as food production, water quality and quantity, sustainable energy, soils in a changing climate, and quality of life.

Anthony Martinez doing field work

Anthony Martinez (MS student)

Anthony earned a Bachelor of Science in Sustainable Forest Management from the University of Washington, followed by a Master of Science in Natural Resources from the University of Idaho while working as a research assistant with Dr. Meddens. He now works for the US Forest Service as the silviculture forester for the 800,000-acre North Fork Ranger District of the Nez Perce-Clearwater National Forest.