30 Mile is committed to preventing the spread of swollen bladderwort from Tilton Pond, at the top of our watershed, and to finding solutions that effectively manage and reduce this invasive species’ impact on the pond’s ecology, recreation, and property values.
We work closely with the Maine Department of Environmental Protection (DEP) to implement best management practices. The DEP provides guidance for our work, assists us in the field, and helps to continue and refine the management plan.
This winter, we worked with DEP to install posts across the Pond’s outlet that will support wire mesh to reduce risk of swollen bladderwort moving downstream to the culvert at Jackman Mills Road. In June, our staff will remove any invasive bladderwort in the area between the screen and culvert to further reduce risk of spread.
Additional work planned for our staff for the upcoming season includes:
- Maintaining four fragment nets in the outlet stream between Jackman Mills Road and East Road
- Conducting multiple early-detection surveys of David Pond (including a diver survey)
- Completing high-priority area surveys of Parker Pond
- Continuing ongoing outreach and education to foster long-term community engagement in prevention, early detection, and control of this invasive.
Currently, large-scale mechanical removal of swollen bladderwort from Tilton Pond is not feasible. Before such work can be considered, the overall abundance of the plant must be reduced dramatically to a manageable level, potentially through herbicide treatment. Because there is no history of herbicides being used on swollen bladderwort in Maine, the DEP is tracking the effectiveness of an herbicide currently being used on swollen bladderwort in Massachusetts. Once they have seen these results, likely by the end of this coming season (one year post-treatment), they will make a decision about approving its use in Maine.
News coverage on DEP’s recent public message regarding Tilton Pond can be found here.
When flowering, swollen bladderwort produces snapdragon-like yellow flowers supported by a vertical stem and a wagon wheel-like floating raft. In Tilton Pond, the plant is typically seen blooming vigorously from late-May to mid-June and again, but sporadically during September.