We are sorry to announce the cancellation of our Kayak Series for 2026. Please stay on the lookout for announcements on next years’ series!
Event: Aquatic Weeds Workshop
The Weed Wire: Tansy Ragwort
History and Native Range: Senecio jacobaea, commonly known as tansy ragwort in the western United States, is a biennial or sometimes perennial flowering plant in the Aster family. Despite its regional common name, tansy ragwort is not a true tansy and goes by many other common names, such as stinking willy, benweed, St. James-wort, staggerwort, or cankerwort. It is native to northern Eurasia, where it naturally grows in sand dunes. Due in large part to its small but abundant seeds, tansy ragwort has since spread beyond its native range to colonize dry, open fields on every continent but Antarctica, mainly through unintentional introductions. Tansy ragwort makes for a somewhat “controversial” plant in many regions, including its native range, as it is both a significant nectar source for many insect species and a nuisance to livestock due to its toxic compounds.
Identification: During the flowering season (between June and November), tansy ragwort can be easily spotted by its flat-topped clusters of small, bright yellow flowers which take the typical aster shape. The leaves are also recognizable by their distinctive ruffled shape and dark green color whether in rosette form or after bolting. Tansy ragwort may be confused for the related and also weedy common groundsel (Senecio vulgaris), but common groundsel is typically smaller (up to 1.5 feet in height) and lighter in color; it also is non-toxic, unlike tansy ragwort.
Tansy ragwort (left) vs common groundsel (right) Photo credit: Oregon State University
The Problem Here: As previously mentioned, tansy ragwort’s toxicity and prolific growth makes it a significant concern for livestock owners- particularly horse and cattle ranchers- and has caused it to be listed as a regulated weed in most places where it occurs, even within its native range. The combination of toxicity and invasiveness leads to significant degradation of both agricultural and wildlife grazing land in the fields, pastures, and grasslands that tansy ragwort tends to grow most abundantly in. Tansy ragwort’s toxins are also known to be absorbed through the skin, though to a much lesser extent than with ingestion.
Manual Control: Digging or hand-pulling tansy ragwort (with gloves, to avoid contact with the toxic plant juices) is an effective method of reducing or eliminating infestations. This is best done when soil is moist, as the taproot can be relatively easily pulled from the ground. Deadheading or mowing tansy when it first begins to flower can also reduce the amount of seed produced, preventing further spread of infestations.
Herbicides: Several forms of herbicide are effective against tansy ragwort, and may be the most efficient method of controlling large infestations. Always follow label directions when applying any herbicide products, and consult with a professional if you need assistance in interpreting the label.
Biological Control: Several biological control species are in use against tansy ragwort; most recognizable is the cinnabar moth, which is almost entirely dependent on tansy ragwort as a food source and uses the toxic compounds of the plant to aid in its own defense, becoming poisonous to predators itself. The tansy ragwort flea beetle is also commonly used in controlling infestations. These biological control species are released by agencies such as the Oregon Department of Agriculture, and are not meant to eliminate tansy ragwort but lessen the intensity of infestations.
Links to Information and Studies:
Oregon Watershed Enhancement Board Small Grant Program
The Small Grant Program is an easy-to-engage-in, competitive grant program that awards grant funding for on-the-ground restoration projects. This program responds to a need for local decision-making about watershed restoration opportunities on a shorter timeframe than is available under OWEB’s regular grant program. A local team of organization representatives review projects and vote on the allocation of the $150,000 from the Oregon Watershed Enhancement Board (OWEB).
The Small Grant Program funds projects including, but not limited to, riparian restoration, upland restoration, Integrated Pest Management (in conjunction with restoration), wetland enhancement, urban impact reduction (stormwater bioswales, vegetation, etc.), irrigation efficiency, livestock fencing (out of creeks and waterways) and fish passage. If you are interested in participating as a team member or applying contact Tyler Clouse (info@lincolnswcd.org) at the Lincoln SWCD.
A Small Grant applicant may be any Tribe, watershed council, soil and water conservation district, not-for-profit corporation, school, Oregon institution of higher education, independent not-for-profit institution of higher education, or political subdivision of this state that is not a state agency. A state agency or federal agency may partner with an eligible entity. If you are a landowner or manager interested in a project you may need to coordinate with an eligible organization to apply.
Upcoming Board Meetings
Our next board meeting will be held on June 11, 2026 via Zoom. These meetings cover the general business of LSWCD, while also convening to decide the next steps the District will take in overall operations or within specific programs.
For registration assistance or special accommodation call the office (541-265-2631) or email Tyler Clouse (info@lincolnswcd.org).
Board of Directors Meetings take place at least once a month, generally on the second Thursday of the month, from 6 to 8 p.m. All meetings are open to the public, with the exception of occasional Executive Sessions.
The Lincoln Soil & Water Conservation District (LSWCD) complies with the American with Disabilities Act (ADA). The ADA prohibits discrimination against persons with disabilities. If you would like to attend a meeting but need special accommodations, please contact us at least 72 hours prior to the meeting.