Document Type


Publication Date

Spring 4-23-2022


One of the greatest changes resulting from industrialization includes improved transportation leading to an increasingly interconnected world. From trains, to ships, to aircraft, modern transportation allows one to cross the globe in a single day. However, such changes have not come without consequences, as greenhouse gas emissions contribute to a warmer climate and rising sea levels. Often lost among these headlines is the growing threat of invasive species. Capable of hitching an unwelcome ride on ships, planes, and other transportation means, invasive species can wreak havoc when introduced to a non-native ecosystem (Westphal et al, 2007). Historically, Maine’s low population density and relatively minimal commercial development has kept the threat of invasives at bay. In part due to rapid development in other New England states, this narrative has begun to change, and invasive species are a growing environmental and social concern in the area. In fact, of the 2,100 plant species known to the state of Maine, approximately one third are non-native (Maine, 2019). While only a small percentage reach invasive status, those that do can cause significant environmental harm. Lacking predators and pathogens in their new environments, invasive species often possess competitive advantages that allow the population to rapidly expand. As a result, they can outcompete native trees, shrubs, and wildflowers, reducing biodiversity and displacing habitat for native wildlife (Olson et al, 2011). Importantly, invasive species can also overtake agriculturally productive farmland, resulting in negative economic and social consequences. With this in mind, our group partnered with Lewiston city arborist Steve Murch, along with Dave Griswold, chair of the Auburn Community Forest Subcommittee, to investigate the density of invasive plant species within Lewiston and Auburn. Having observed the growing threat of invasives through years of forestry related work, Steve and Dave have an extensive knowledge of the array of native and non-native plant species in the local area. In fact, Steve has led city crews in recent efforts to manage the spread of invasives while maintaining the city’s public spaces. Dave has also worked in the management of invasive species as a forester with the state of Maine. Now, their focus has shifted to raising local awareness of the issue. They are working to develop a comprehensive management plan that will be proposed to the state of Maine, with the goal of receiving future grants for removal and control measures. Accordingly, our goal was to act as an early step in gathering momentum and 1 increasing awareness of invasive plant species impacting the local area. To do so, Steve and Dave helped us narrow the geographic focus of our study to four areas of high recreational use: Simard Payne Park, Pettengill Park, Auburn Riverwalk, and the Androscoggin Riverside Trail. Within these areas, we aimed to quantify the concentrations of four invasive species, Japanese Knotweed, Oriental Bittersweet, Japanese Barberry, and the Norway Maple, using the ground transect method. Through the development of a visual scale and an informational pamphlet, our goal is to raise local awareness of invasive plant species in order to grow public support for a future management plan.