When you take a look at the academic programs at Ozarks, you'll find a number of courses that are pretty unique. But there is one course that offers students a truly one-of-a-kind college experience, at least for students in the state of Arkansas - BIO 4234, Lichenology.
The lichenology course is an upper level applied botany course that investigates the anatomy, physiology, and taxonomy of lichens. "This is the only lichenology class in the state of Arkansas, and one of the few in the entire region," said Dr. Doug Jeffries, who teaches the course. "Because lichens have very little commercial value (which is good for them) they don’t get a lot of exposure."
For those who don’t know what lichens are, Jeffries offers this explanation. "Lichens are a composite organism," he said, "which survive through a special type of symbiosis." Symbiosis is a term that refers to an interaction between two organisms that live in close association, an interaction that normally offers a survival advantage to both organisms. "Lichens were the first symbiotic organisms discovered that were an association between a fungus and an algae," he said. "The fungus and algae are actually distinct species, but through the symbiotic relationship the fungus actually changes shape, and even the chemicals the lichen makes are unique."
Jeffries said that lichens are divided into three groups based on their shape and growth patterns. The foliose (leaf-like) lichens are commonly found growing on tree trunks or on rocks. These are the flattened, often circular growths one might find adorning the facade of an old stone building, or on older gravestones. A second group, the fruticose (shrub-like) lichens, looks more like a plant. Common examples of fruticose lichens in Arkansas are the reindeer moss (Cladonia sp.) found growing in rounded clumps in the forest, and old man’s beard (Usnea longissim), which resembles the Spanish moss found growing in the deep south. A third group of lichens, the crustose lichens, are found growing closely adhered to, or even inside, rocks.
But while lichens are an interesting and unique group of organisms, Jeffries said his lichenology course wasn’t created just to teach students about lichens. "This class is a different kind of science class than all the others [students] take," he said, "because it’s a taxonomy class. It gives them experience in that area, because taxonomy is so very different from experimental biology." He said that this class teaches students a number of skills and techniques that will be useful in later studies or even for those working in the field of wildlife biology, such as how to use taxonomic keys. Because the class is a taxonomy class, it consists primarily of field and lab work, with very little lecture.
Students in Dr. Jeffries lichenology class examine a specimen collected from Wolf Pen Mountain during a recent field trip to the glade located on the mountain.
The course is required for students majoring in Biology on the Ecology and Wildlife Biology track, but Jeffries said it is open to any student who has an interest in learning these special field and lab techniques, and who has completed the prerequisites for the course. "I generally teach a class every two years," he said. "The class is taught in the spring so we can do our field trips in January and February, because that’s when the lichens are active. Lichens are not like most plants. Most plants have an optimum temperature in the upper 60s or lower 70s. For lichens, the optimum temperature is about 50 degrees."
For these field trips, Jeffries takes the students to four or five different locations to collect specimens. "Lichens like acid conditions," he said, "so they like acid soils, and acid rocks. There are some rocky outcrops found in the forests where trees can’t grow and those are called ‘glades.’ Sandstone glades are one of the best locations to find lichens." Jeffries said the best glades he has located within driving distance of campus are at Mt. Morgan (near Cass), a glade at the top of Wolf Pen Mountain, Cedar glade (near the Harmony community), and Strawberry bluff.
While there are around 15,000 lichen species found world-wide, Jeffries said that only a two or three hundred are found in Arkansas. However, he is quick to point out that students don’t have to know any lichen species by sight in order to take the class, since the whole point is to teach them the identification techniques. Prior to the first collecting trip, the students learn some basic terminology associated with lichens, and learn about the collection techniques they’ll need to use in the field. "They just pretty much collect everything they can, and we bring it back and try to identify it," he said.
With only two collecting trips behind them, the students in this spring’s class have already started working on the initial identifications for their specimens. A dissecting microscope sits on the lab table beside a cardboard box filled with folded paper bags. Matt Friant, a sophomore environmental studies major, selects a bag from the box and carefully lifts the lichen specimen onto the table. He flips open the course textbook, "How to Know the Lichens" as classmate Trent Ueunten, who is a junior environmental studies major, looks on. "We’re trying to identify some of the specimens we collected during our last two labs," he explained, flipping through the pages to the taxonomic key. Friant said that the first step in the identification process is to examine the visual characteristics of the specimen under the microscope. Some specimens, he said, can be quickly identified in this way, while others appear so similar that it simply isn’t possible to identify them based on their physical characteristics. In these situations, Friant said the specimen will be set aside, to be examined later with a different set of techniques. "Some of the different species can look so much alike - when we can’t tell them apart visually, that’s when we move to the chemical tests," he said.
These chemical tests, Jeffries said, are often the only way to identify certain lichens, and work by identifying the specific chemicals that are produced within the lichen. "Most chemicals lichens make are unique to lichens," he explained. "Each lichen has only two or three different chemicals, so you can identify the lichen by finding out what chemicals it makes." He said the students will use thin-layer chromatography and different types of chemical spot tests to identify those lichens that can’t be differentiated by visual inspection - they’ll learn these chemical identification techniques as part of the class.
Because there is very little lecture in the course, Jeffries said he doesn’t give a written final for the course. Instead, the students are graded on their lichen collection, which is due at the end of the semester. The process of creating the collection is yet another learning experience that teaches skills integral to taxonomic research. "You learn a lot of Latin," Friant said, and Ueunten laughed as he added, "You learn how to pronounce things!" Jeffries said that the students are also required to turn in their field notebook with their collection. "They give each specimen a number when they collect it. This information goes into a field notebook to tell where they got it, what color it was, and what substrate it was on," he said. Jeffries noted that recording these types of details is critical when collecting specimens for taxonomic research.
In addition to creating their own collections, Friant and Ueunten said the students in the class will be helping Dr. Jeffries expand and organize the university’s lichen collection during the semester. As they collect, they will initially glue the specimens to cards, and store them in paper bags. "Later we’ll wrap them up in blue envelopes (blue standing for Arkansas because we have some yellow packets that came from Arizona), and they’ll be added to Dr. Jeffries’ permanent collection." Friant explained.
Jeffries said this is the sixth time he has taught the lichenology course. He believes that the unique aspects of this course add an important dimension to the biology major. "I consider lichenology my professional hobby," Jeffries said. "There’s no other organism like them on earth. There’s no other symbiosis that changes the shape of both of the organisms in the relationship." And while he doesn’t expect that his students will necessarily come to think of lichenology in that same way, the one-of-kind experience they gain during the course can be invaluable to those who pursue graduate studies in biology. "Odds are they won’t become lichenologists," he said, "but if they go into a class that is a taxonomy class, they’ll know some general things about how taxonomy works."
Topics: Biology