Field Studies

A look at the vast range of impactful research being conducted by faculty and students inside Hopkins Memorial Forest.

 

On a crisp, early autumn afternoon, more than a dozen students in biology professor Manuel Morales’ “Ecology” course survey a small field deep inside Hopkins Memorial Forest, their eyes scanning the ground for grasshoppers. 

Equipped with sandwich bags and red and white paint pens, the students spend 15 minutes gathering as many of the wily insects as they can. “I had no idea it would be so difficult,” says one student, as he dives his hands into the grass, hoping to add one more grasshopper to his lot. 

When the 15 minutes are up, the students mark each grasshopper’s abdomen with a small red dot and then release them all back into the field, a practice called “free mixing.” After a few minutes, the class begins a new search in the same area, marking each insect they recapture with white pens. 

Given the grasshoppers’ short lifespans—they disappear from the forest around mid-October—the exercise takes place within a tight window, Morales says. The goal is to estimate the total population in the field as well as provide students with a hands-on way to learn mark-recapture techniques, which are essential for conservation and management efforts. 

“Field studies like this one are central to ecological research, and Williams is extremely fortunate to have a research forest only minutes from campus,” says Morales, who chairs the Hopkins Memorial Forest Users Committee. “Students love these outdoor labs, which are almost universally highlighted as one of their favorite parts about the course.”

The mark-recapture activity is just one of the many ways Williams utilizes the 2,600-acre forest, which spans parts of Massachusetts, New York and Vermont. The forest is also the homelands of the Stockbridge-Munsee Community, one of 574 federally recognized tribes in the United States.

Hopkins Memorial Forest is best known to the wider community as a place for nature walks, events such as Forest Fridays and MapleFest, and field trips for school children around the region. But it’s the vast range of impactful research that takes place here that truly sets it apart from other woodlands. What follows is an illustrated look at some of the insects, birds, flora, fauna and other natural phenomena faculty and students are studying in Williams’ largest lab.

Garlic Mustard (Alliaria petiolata) (pictured at top)
For more than 20 years, biology professor Joan Edwards and her students have been conducting research on the population dynamics of one of the most intensively studied invasive plant species in the United States: garlic mustard. Edwards and legions of student assistants have collected samples and analyzed data over time from established plots in three different areas of Hopkins Forest. The analysis provides insight into garlic mustard’s success in forests of different ages. Specifically, Edwards and her team have examined the plant’s rate of invasion. Their studies show that, in the mid-successional red oak stand, the heavy leaf litter layer that blankets the forest floor each fall and buries the garlic mustard likely prevents it from invading.

Ecosystem-Level Isotope Tracing
In her course “Geochemistry: Understanding Earth’s Environment,” geosciences professor Mea Cook and her students conduct fieldwork in Hopkins Forest to study how chemical elements are distributed in the Earth, cycle through the Earth system (composed of the geosphere, biosphere, cryosphere, hydrosphere and atmosphere) and function together to produce a habitable planet. By collecting, analyzing and interpreting data from environmental samples, their work examines how Earth’s landscapes and oceans—and the life they harbor—have evolved through time. “It was a huge amount of fun to learn how to do the fieldwork,” Cook says, adding that her class “enjoyed thinking about carbon and nitrogen stable isotopes in a modern system, as well as how they’re used in the geological record to infer past climate, nutrient dynamics and paleoecology.”

Northern Saw-whet Owl (Aegolius acadicus)
Hopkins Forest has long maintained one of the approximately 100 stations in the U.S. and Canada to track Northern Saw-whet owls with the aim of learning more about the species’ population dynamics. During the owl’s fall migration, from October to mid-November, researchers from around the region, including biology professor Manuel Morales, use an audio lure and mist nets to capture and band these small creatures so they can be tracked throughout the following year. In 2020, the researchers caught 207 Saw-whets, the third-highest number to date. Continued recoveries of banded Saw-whet owls at Hopkins and other stations provide additional information on their migration routes and timing, growth, survivorship and molt progressions.

Treehopper (Publilia concava), Ant (Formica sp.) and Goldenrod (Solidago altissima)
Treehoppers—​​not to be confused with the grasshoppers studied in Manuel Morales’ “Ecology” class—are central to research on the ecological and evolutionary dynamics of mutualism, a type of symbiotic relationship where all species involved benefit from their interactions. In this case, an abundance of treehoppers in Hopkins Forest feed on fields of goldenrod, a nitrogen-poor, carbohydrate-rich plant. The insects produce a secretion called honeydew that provides a food source for ants, who, in turn, protect treehoppers from predators. Building on research from a three-year, $244,117 National Science Foundation grant that Morales and chemistry professor Enrique Peacock-Lopez received in 2015, Morales and his students conduct fieldwork during the summer to study the medium- to long-term effects on the goldenrod’s quality as well as potential changes in the vigor and density of herbivore populations. Students also learn how the insects and plants interact with and affect one another.

Soil Carbon
Biology professor Allison Gill and her students are exploring how nitrogen supply influences the formation and protection of soil carbon, the largest terrestrial carbon pool. The team takes samples from two sites in Hopkins Forest—one at a higher elevation dominated by yellow birch and American beech trees, and one at a lower-elevation area where sugar maples are prevalent. In June, Gill received a three-year, $491,000 National Science Foundation grant to expand the research, about which she and her students have published extensively. She is integrating their findings into new courses such as the interdisciplinary laboratory class “Ecosystem Ecology in the Anthropocene” and “The Nitrogen Problem,” a biology seminar focused on managing nitrogen pollution. With the grant, the group’s research will help improve predictions of future atmospheric carbon dioxide concentrations.

Weather Stations
Students in geosciences professor Alice Bradley’s fall-semester course “Environmental Observation” set up weather stations in Hopkins Forest to measure the impacts of tree shading on surface-level weather. “We do this to get a sense of how important documentation is in getting consistent measurements, practicing thinking through study design and building hands-on skills,” Bradley says. She and her students construct the stations and leave them out for a couple of weeks to log data, which are analyzed later in the term. The class also looks at the impact of location on the numbers—meteorological measurements can also be collected at the Taconic Ridge and the Class of 1966 Environmental Center, for example. “Hopkins Forest is a fantastic resource,” Bradley says. “Having the forest so close to campus provides the opportunity to go from the classroom to field experience in minutes.”

Mowing Patterns And Pollinators
The timing and frequency of mowing can have a major impact on floral production and pollinator activity—a topic of global concern given declines in pollinating insect populations. Biology professor Joan Edwards, winner of the Botanical Society of America’s Charles Edwin Bessey Teaching Award for 2024, has led a study since 2012 in Hopkins Forest that experiments with various mowing patterns. Edwards created 16 plots of land divided into four blocks, each with its own mowing regime. She and her students gather data on the plots every autumn. Studying the effects of different mowing frequency and timing—early annual in late July, early biennial, late annual in late October and late biennial mowing—increases understanding of mowing’s long- and short-term impact on floral resources. Edwards says that waiting to mow until after the first frost significantly increases the number of flowering stems, which are critical resources for pollinating insects. 

 

 

“With the twin environmental crises of climate change and biodiversity loss, understanding the natural world, how it functions and how it can ameliorate environmental pressures is critical for all to understand. Hopkins Memorial Forest provides easy access for all to experience the natural world firsthand and to learn through careful observation, field labs, research and enjoyment of nature.”
-Joan Edwards, Williams’ Samuel Fessenden Clarke Professor of Biology

 

 

Watch and listen to some of the sights and sounds of Hopkins Forest: