The Rare Pitcher’s Thistle
Door County land Trust’s Sturgeon Bay Ship Canal Nature Preserve is home to one of the Great Lake’s largest populations of the federally threatened Pitcher’s thistle. Pitcher’s thistle, scientifically known as Cirsium pitcheri, is only found surrounding the Great Lakes and is one of Wisconsin’s hidden wonders.
Thanks to a partnership with the Chicago Botanic Garden, research conducted at the Sturgeon Bay Ship Canal dunes has included observation of pollinating insects and a thorough evaluation of the Pitcher’s thistle population trend—which has shown a strong growth.
Over the past ten years, Door County Land Trust has been managing the dune habitat at the Sturgeon Bay Ship Canal Nature Preserve to improve conditions for the thistle by removing invasive species like honeysuckle, spotted knapweed, bouncing bet, and crown vetch.
With recent high waters on Lake Michigan and the erosion of sand dune shorelines, the populations of thistles found along the Sturgeon Bay Ship Canal Nature Preserve and Southern Lake Michigan Drive are more important than ever. The Pitcher’s thistle needs more quality habitat if it is to survive—and we believe this area is among the best habitat in Door County.
In summer 2021, Door County Land Trust and Chicago Botanic Garden are launching a restoration project to restore dune habitat in the area.
Landowners are invited to participate in the project in the following ways:
- Schedule a site visit this summer with Chicago Botanic researchers or DCLT staff to walk your property and look for Pitcher’s thistle and any invasive species that might be threatening them. We will provide you a follow up report after our visit.
- If your property does include Pitcher’s thistle and you would like to be included in the CBG research project, researchers will study the pollinators and evaluate the number and quality of seeds produced by plants on your property throughout the summer of 2021 (more info included separately).
- Provide you educational materials for identifying and monitoring Pitcher’s thistle plants on your land.
- Invite you to join a private event at Ship Canal Nature Preserve on July 7th, hosted by DCLT, with Chicago Botanic Garden researchers leading a hike about the project and Pitcher’s thistle.