University of Vermont

Clare Crosby Helps Vermont Nonprofits Re-think Approach to Invasive Plant Management

Graduate student research profile

Clare Crosby is a master's student in Ecological Planning.
Clare Crosby is a master's student in Ecological Planning.

A conservation organization can protect a natural area from logging or development, but invasive plants routinely hop fences and scoff at legislation. That is why I am helping The Nature Conservancy (TNC) and the Vermont Land Trust (VLT) rethink their approach to managing invasives in and around natural areas. By analyzing distribution of invasives on private lands, I am helping to guide future management efforts throughout the Northern Champlain Valley and particularly around TNC natural areas.

Along with an intern from TNC, I bushwhacked through tangles of invasive honeysuckle, ate native blueberries atop rocky outcrops, and tried in vain to find an effective non-DEET mosquito repellant. The experience completely debunked the “Tangle Test” ( I developed last spring, in which I could tell it was a great day if my hair had picked up a collection of twigs and leaves. The days with open understories were glorious.

We visited 22 properties throughout the field season, using an iPad to create maps of invasive plant cover and distribution. We produced a report for each landowner, recounting the current state of invasive plants on the property, explaining the importance of control, and offering prioritization recommendations to maximize effectiveness of management with the lowest cost.

In addition to initial outreach to landowners, I have spent the fall analyzing the data we collected over the summer. I am investigating patterns of invasion related to forest patch size, distance from roads, a variety of soil characteristics, and historic and current land cover. I applied lessons from Research Associate Jarlath O’Neil-Dunne’s GIS Practicum course to acquire or generate datasets for each of those factors, combine them with my invasive plant data, and develop models to output data in forms I could use for a variety of statistical analyses. I will use any patterns (or perhaps lack of patterns) I find to guide recommendations for TNC and VLT as they work with landowners in the Northern Champlain Valley to collaboratively combat invasive plants in the area.

My work is part of a larger project by TNC and VLT, funded by a grant from the US Forest Service, focused on invasive plant management throughout Vermont. All of the data we gathered over the summer has been added to, an online database of invasive plant distribution and abundance information. Recommendations from my study will allow TNC to select priority areas for continued outreach to private landowners, especially surrounding their natural area. It will also help guide VLT’s outreach to their landowners regarding invasive plant monitoring and management recommendations.