Hamilton’s Kirkland and Rogers glens offer beautiful forest paths for joggers, dog-walkers and nature lovers. While anyone can appreciate the lush variety of plant life in these areas, a well-trained eye can spot several plant species growing there that aren’t native to the glens. Invasive plant species in forests have the potential to interfere with native plants and animals, as well as disrupt the microbial balance of the soil.
This summer Daniel Feinberg ’12, Ana Fernandez-Menjivar ’13, Dilyana Mihaylova ’12, Bethany O’Meara ’12 and Matthew Combs ’13 are working under Associate Professor of Biology William Pfitsch to study some of these invasive species. Their project involves mapping the abundance of invasive plant species around different areas of the glens and the Hamilton College Reservoir area, laying the foundation for future study.
Invasive species are plants or animals that thrive and occupy resources in areas that are nonnative to the species. In the glen, such plants can be introduced as a result of reforestation efforts or from garden herbs spreading into the forest. Pfitsch’s group is looking at the five most prevalent invasive plant species to the glen: garlic mustard, buckthorn, honeysuckle, barberry and multiflora rose. Among these, they are focusing most on garlic mustard and comparing it to wild leek, which is native to the glen. Because wild leek and garlic mustard are similar, the group hopes to use both plants to examine whether the growth garlic mustard crowds out the growth of wild leek.
There are several factors that influence the growth and concentration of invasive species. For example, soil that has been recently disturbed is especially hospitable to invasive species because the invaders occupy the fresh area more quickly than many native plants can grow in. For this reason, invasive plants can frequently be found alongside paths or riverbeds. Furthermore, the group is studying the growth of invasive species with regard to the historical background of the land. Depending on the soil’s previous uses, such as for farmland, certain invasive species may be more or less likely to take root there.
To survey each area, the group measures an area of 100 meters and marks it with tape, then marks off a 25 meter line perpendicular the 100 meter line. Each member takes five meters along this 25 meter strip, and the group walks along the 100 meter area, recording findings on paper every 10 meters. After each 100 meters, they mark their coordinates with a handheld GPS. Despite the large areas that the students cover, they move through their work quickly and efficiently, studying the ground for any of the five species they are targeting. After surveying the land, the group returns to the lab to input their findings into a Geographic Information System (GIS). GIS technology allows the students to overlay their findings on a map of the region with the help of Geosciences Technician David Tewksbury.
The study of invasive plant species can extend to many areas. For example, this project may be carried out further to examine how the microbial balance of the soil changes when invasive plants grow in the soil. Feinberg, who is interested in studying salamanders, wishes to use his current research to further his senior thesis.
Though their work includes battling mosquitoes, spiders and thick forest growth, they enjoy their time outdoors and one another’s company. The group’s research is helping uncover more about the forested areas that the Hamilton and surrounding community enjoys.
Matthew Combs is a graduate of Rogers High School in Newport, R.I.; Daniel Feinberg graduated from the Friends School of Baltimore (Md.); Ana Fernandez-Menjivar is a graduate of the United Nations International School (N.Y.); Bethany O’Meara graduated from Cape Elizabeth High School (Maine); Dilyana Mihaylova is a graduate of First Language School in Varna, Bulgaria.