Plant physiological ecology
the study of plant form and function within the ecological context
I am an assistant professor of biology at Pepperdine University. My research explores how plants can survive drought, fire, and salinity. Are you curious about how plants work? My lab asks questions about how plants use water, and how that water use changes with environmental stressors.
Southern California is historically a drought-impacted ecosystem, and native plants have adapted to thrive here. However, recent years have seen longer and more severe droughts as well as increased fire frequency. Will the plants survive? Or will some species become locally extinct?
Undergraduate Research with Dr. Holmlund

Are you interested in exploring research opportunities at Pepperdine? Check out our lab’s research page to learn more about what projects you could design in our lab!
Ferns
Ferns typically need lots of water to survive, but some ferns can thrive without much water. Here in the Santa Monica Mountains surrounding Pepperdine University, ferns have adapted to survive seasonal drought. Click here to learn more about our lab’s work on drought-adapted ferns.
Chaparral
The chaparral is the dominant vegetation type in coastal southern California. Plants in the chaparral have adapted to survive seasonal drought and frequent fire. However, recent years have seen longer and more severe droughts as well as more frequent fires. Can the chaparral plants survive these changes? Click here to learn about opportunities for studying chaparral response to climate change.
Island Biology
The Channel Islands off the coast of southern California provide exciting opportunities to study plant adaptations to island environments. For instance, the Channel Islands experience more frequent fog than the mainland ecosystem. Our research has shown that the island plants may have adapted to take advantage of the extra fog water. Click here to learn more about our work on Santa Cruz Island.
Salt Tolerance
Saltwater kills most plants, but some plants thrive in the saltwater mangrove swamps along the coasts of the tropics. In fact, there are even some species of ferns that thrive in saltwater. I am researching how these mangrove ferns (genus Acrostichum) adjust their water relations to thrive in the saltwater habitat. Click here to learn more about our work on the mangrove ferns.
Lab News
Life as a botanist is always an adventure!
- Field work in Costa RicaLast May, my student Jordyn Regier and I went to Costa Rica to investigate opportunities for future research projects. We found and identified so many ferns! We spent about a week hiking through the jungle and collecting preliminary data. I can’t wait to return! Jordyn worked with me for an NSF REU fellowship at PepperdineContinue reading “Field work in Costa Rica”
- SURB Students present research at SCCURA couple weeks ago, three students in my lab (Mayra Hernandez, Jordyn Regier, and Camille Sicangco) presented their research at the Southern California Conference for Undergraduate Research (program available here). They presented the projects that they initiated last summer during Pepperdine’s SURB program (our NSF REU Site Program). Mayra presented her research on coastal sageContinue reading “SURB Students present research at SCCUR”
- Resurrection ferns in New Phytologist’s blogNew Phytologist’s blog recently featured our 2019 research article on the resurrection ferns. The blog post features a fluorescence micrograph of a resurrection fern stem by Dr. Anna Jacobsen (shown above). Click on the link below to read the blog post. Here is the citation for our 2019 article: Holmlund, H.I., Pratt, R.B., Jacobsen, A.L.,Continue reading “Resurrection ferns in New Phytologist’s blog”
