Land Plants - invasive

Tansy Ragwort (Senecio jacobaea) on May 24, 2022

Submitter does not have a specimen

Description of specimen

This is known to be in the field with many other species of plants going to seed in this field.


Hi Dylan,
Thank you for reporting this tansy ragwort infestation. Tansy is widespread across Marion County and is targeted using biological control. Bio-controls slow the spread of tansy, but will not eradicate it. Further control measures are required to eradicate infestations and it's especially important to control in areas with grazing livestock. Unfortunately, because tansy is so widespread, control is the responsibility of individual landowners. Sometimes, connecting with your neighbors and educating them about the dangers of tansy can have a big impact. Many new landowners in our area aren't aware of tansy or its impact on livestock.

Below you will find a couple of resources you may find useful. It includes treatment information. Now is a great time to control tansy before it flowers and goes to seed.

If you have additional questions please feel free to contact me directly. Thanks again for the report.

Sarah Hamilton

Sarah Hamilton (she/her)
Native & Invasive Plant Specialist
503.949.6832 (work cell)

Sarah Hamilton
May 25, 2022, 8:29 a.m.