In our continued work to help increase the availability of plant materials for pollinator conservation, Xerces staff conducted propagation and outplanting trials on Cirsium occidentale (cobweb thistle), an important nectar plant for pollinators. Cobweb thistle provides critical pollen and nectar resources for monarchs and other declining pollinators. However, it has very limited commercial availability and thus is not widely used in restoration projects. Building from this industry knowledge, we sought to find ways to produce more successful transplants for this species.
This four-page report details the results of the 2024–2025 trials testing the efficacy of two container sizes as well as the survivability of seedlings planted at two intervals.