Ecological Research

I received my Master of Science degree from the University of Washington School of Environmental & Forest Sciences under advisor Dr. Jonathan Bakker, P.I. of UW’s Terrestrial Restoration Ecology Lab. My research focus was the chemical ecology of Puget Sound prairie plants, using two forb species as my study system: the native hemiparasite Castilleja levisecta (golden paintbrush) and the exotic European Plantago lanceolata (narrowleaf plantain).

A clump of yellow blooms and stems on a golden paintbrush plant at Glacial Heritage Preserve — *Castilleja levisecta*, Glacial Heritage Preserve, Littlerock, Washington, USA

The Castilleja genus is hemiparasitic, meaning these plants can carry out photosynthesis and survive on their own, but they are more successful when parasitizing a host plant. Their roots form haustorial connections with a host plant’s roots and siphon off the products of the host plant’s photosynthesis. My colleague, Dr. Natalie Schmidt, explored the relationship between C. levisecta and its hosts in her research.

Magnified image of hemiparasite root haustoria attached to host plant roots — Haustorial connections between *C. levisecta* and host plant roots. Photo by Rae Mecka.

Prior to beginning my graduate research, I worked as a seed germination and viability testing technician in the TRE Lab. One of our projects focused on testing the viability of putative hybrid Castilleja levisecta × Castilleja hispida seeds. And why did we care about germination rates for these hybrid seeds? Castilleja levisecta and Castilleja hispida are both native Puget Sound prairie species, but the former, as of 2018, was considered threatened, while the latter was not. South Sound prairie restoration experts initially did not realize that these two species would hybridize if seeded together on the abandoned agricultural land the experts were restoring to native prairie habitat. I won’t get into the weeds (ha!) of what constitutes a distinct species or what hybridization might mean for the funding of species recovery efforts. Suffice it to say that land managers and researchers were alarmed to see Castilleja plants with suspicious intermediate traits popping up. See, Castilleja levisecta has yellow bracts, and the bracts tend to be more tightly closed. In contrast, Castilleja hispida typically has open reddish bracts (though colors can range from red to orange or even orange-yellow). The two species also have noticeable differences in leaf morphology. These putative hybrids exhibited intermediate traits in bract and leaf morphology, bract color, and bract openness.

Three images placed in a row for the purpose of comparison, with golden paintbrush on the far left, harsh paintbrush on the far right, and a putative hybrid plant with intermediate traits in the center. — Morphological differences among *Castilleja levisecta* (CALE), *Castilleja hispida* (CAHI), and a putative hybrid. Photos by Dr. Peter Dunwiddie.

This situation resulted in further research on hybridization between these two species. In the years since, land managers and researchers have been vigilant about locating any C. hispida or putative hybrid plants at a few different South Sound prairie restoration sites. These plants are uprooted for the sake of C. levisecta recovery efforts. It is of course impossible to uproot them all, and it is also impossible to tell whether a putative hybrid is actually a hybrid without genetic testing. In 2015, the TRE Lab shipped putative hybrid leaf samples to researchers at Chicago Botanic Garden (CBG) to better understand the genetic makeup of these plants. The results of the CBG study are presented in this research poster.

The loose dirt of a rodent tunnel is seen mounded among various grasses and wildflowers. — A rainbow of *Castilleja levisecta*, *C. hispida*, and everything in between. Various burrowing mammals enjoy feasting on this genus, which might explain the evidence of burrowing around the plants. Scatter Creek Wildlife Area, West Rocky Prairie Unit, June 14, 2017.

The TRE lab cared about knowing the viability and germination rates for seeds of putative Castilleja hybrids so we could better understand the implications of multiple generations of genetic backcrossing for species recovery efforts. If first-generation hybrid seeds are viable and grow to become plants that then hybridize with C. levisecta or C. hispida, what would that mean for C. levisecta conservation efforts? We found that the hybrid seeds are, indeed, quite viable! (See research poster with results.) This may prove to be an important concern for broader Puget Sound species recovery efforts. For example, Dr. Nate Haan found that C. levisecta and C. hispida may differ in their potential to serve as quality hosts for endangered Taylor’s checkerspot butterfly larvae, indicating that hybrids of the two species might also vary in suitability as larval host plants.

Magnified image of beautiful pyramid shaped paintbrush seeds with a fascinating crystal lattice like surface. — Seeds of putative *Castilleja levisecta × C. hispida* individual

I spent the 2016 and 2017 growing seasons collecting hundreds of leaf samples from marked Castilleja levisecta and Plantago lanceolata plants in my research plots at Glacial Heritage Preserve. I collected leaves during the early, mid, and late growing season in both years, often in cold and rainy weather, which was a challenge, since the leaves had to be stored in paper coin envelopes that rapidly became soggy in heavy rain. On some especially difficult days I collected leaves for 12 hours straight, stopping only for quick meal breaks. I alternated between listening to the sounds of ospreys on the prairie wind and podcasts about cryptocurrencies and blockchain technology. At the end of a sampling day, I would drive more than two hours in horrendous I-5 evening traffic back to the TRE lab while listening to episodes from the archives of The Partially Examined Life. Back at the lab, I would place paper bags filled with coin envelopes of leaves into the lab drying oven, where the leaves would spend several days drying before being pulverized with mortar and pestle by our faithful undergraduate lab technicians, Alishia Orloff and Victoria Fox. The samples were then shipped to the Bowers Lab at University of Colorado for iridoid glycoside concentration analysis.

We were interested in iridoid glycoside concentrations primarily because the larvae of the endangered Taylor’s checkerspot butterfly have developed a tolerance for these plant antiherbivory compounds and are able to sequester the compounds into their own bodily tissues as they devour leaves of the two species I was researching. This appears to render their flesh unpalatable to predators, enhancing their chances of surviving to adulthood.

After bursting into tears at least once over malfunctioning R code during the thesis writing process, and with much mentorship from my committee members, I at last managed to wrangle all of my data and field notes into a single imperfect document. In December 2017 I defended my thesis, complete with an ecology musical number that I’m confident my long-suffering advisor will never forget. I then spent the next couple of months working on thesis revisions for my final submission. On March 15, 2018 I finished removing temporary fencing materials from my research plots at Glacial Heritage Preserve. I arrived early in the morning, when it was still cold and frosty. By the time I had finished hauling a pile of heavy iron t-posts out from the plots, the sun had burned off the fog and the prairie looked like an entirely different place. I spent the early afternoon walking to the most distant edge of the preserve where the grassland gives way to Douglas fir forest. Here are my photos from the day.

The sun lightly shines through the foggy sky above a frosty winter-brown mounded grassland — Natural Mima mounds create a fascinating landscape across the prairies outside of Littlerock, Washington

A frost covered dead flower head from the previous year's growing season with brown frosty grassland in the background.

Yellow crustose lichen speckles the branches of a small deciduous tree that has not yet sprouted spring leaves. The grass and dirt road in the background look brown and covered in frost. — The dirt road to the UW research plots

Two birdhouse structures are attached high up on a tall wooden pole that is erected on a mounded, frosty grassland. The grass is brown from winter and the sky is foggy. — The Center for Natural Lands Management builds structures to house western bluebird and osprey nests throughout the preserve

A 1995 Toyota Camry is parked at the top of grassy knoll with iron t-posts hanging out of the trunk. — Hauling t-posts out in a valiant ’95 Camry

Frost covered spider web strands hang like Christmas garlands between dead flower stalks from the previous year's growing season. The sky in the background is misty with fog.

We see the empty interior cells of a broken preying mantis ootheca that remains attached to the concave surface of a rust-speckled iron t-post. — Vacated praying mantis ootheca found attached to a t-post

A beautiful frost covered spider web hangs between dead flower stems from the previous year's growing season.

Remnant dead flower heads from the previous year's growing season rise above the mounded brown grassy surface of the prairie.

Pale green lichen fruiting bodies grow like strange stalactites or thick shag carpet from a crusted mat of moss and prairie dirt. A bright green lupine seedling with its bean-like cotyledons emerges from the crusted mat among the lichen fruiting bodies. — A lupine seedling with lichen among the prairie grass might cause one to wonder how thick mats of moss and lichen on the prairie soil might affect seed germination. Do these thick mats hinder or enhance germination? Or do they have no effect at all?

A light foggy mist hangs in the air above a mounded grassland with Douglas fir forest at its edge.

The mist of melting and evaporating frost rises from the mounded surface of the prairie at the edge where grassland meets Douglas fir forest. The sky is grey from the receding morning fog.

A wooden platform with an osprey nest sits atop a very tall wooden pole in the middle of a Mima mounded grassland. In the distance one can see thick Douglas fir forest. — Structure for osprey and western bluebird nests.

A fluffy mounded cushion of pale green reindeer lichen sits among the dried brown grass and bracken fern fronds of the prairie. — In some parts of the prairie there are thick pillows of reindeer lichen. Note the senesced fronds of bracken fern among the grass.

A wooden bat house is erected between two tall wooden poles in an open grassy area with a row of Douglas fir trees in the background. The grass is brown because it is very early spring, and the sky is blue streaked with gossamer white clouds. — Structures for bats.

Pale green lichen and moss covers the winter twigs of on oak tree in fur and velvet like patches. A few dead brown oak leaves still cling to the branches. — Lichen growing on a Garry oak.

In the foreground, thick moss clings to the branches of some old and mostly dead Douglas fir trees. Behind these dying trees is a dense group of healthy Douglas fir trees. — At the edge of the prairie one encounters the Douglas fir forest. Traditionally, indigenous peoples used occasional fire to keep the forest from encroaching on the prairies that produced plants useful for food, such as camas, which has an edible potato-like bulb.

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