Image of Tansy ragwort

Tansy ragwort
Senecio jacobaea

  • Tansy ragwort is established in Oregon and Washington. Infestations have recently been found in Idaho. Idaho has listed this weed as noxious.
  • Tansy ragwort is a biennial or short-lived perennial. Most seeds will germinate in the fall and form a rosette. The plants send up flower stalks the second spring and then die. However, damage prior to the plant maturing may delay death and cause regrowth the following year.
  • The leaves are attached directly to the main stalk and grow from 2 to 9 inches long. The stalk may grow to 6 feet in height. Golden, daisy-like flower heads grow at the tips of each branch. Each weed may produce as many as 150,000 seeds. Most seeds fall close to the parent. Some are carried by wind and water.
  • All parts of this weed are poisonous. It causes liver damage to cattle and horses. Sheep are affected to some extent.
PreviousWeed Main PageNext

Report Sightings of Noxious Weeds

Contact:
Kim Pierson, USFS Botanist
208-737-3212
kpierson@fs.fed.us

SPREAD THE WORD ... NOT THE WEEDS
  • Drive only on established roads and trails away from weed infested areas.
  • When using pack animals, carry only feed that is certified weed free.
  • Removed weed seeds from pack animals.
  • Don't pick the flowers of noxious weeds and take them home.
  • Don't pick and transport wild flowers that you can't identify.
  • Don't camp or drive in weed infested areas.

Weed Removal Instructions

No Flowers or Seed Present:
Pull the weed and leave it on the area.

Flowers or seed present on the weed:
Pull the weed. Be careful the seed does not fall from the weed. Place the weed in a plastic bag or similar container.

Dispose of the weed by burning or turn it in at a Ranger Station.

Chicory | Common Crupina | Common Tansy | Dalmation Toadflax | Diffuse Knapweed | Hoary Cress | Hound's Tongue | Kochia | Leafy Spurge | Meadow Hawkweed | Musk Thistle | Orange Hawkweed | Poison Hemlock | Purple Loosestrife | Rush Skeltonweed | Russian Knapweed | Scotch Thistle | Spotted Knapweed | Common St. Johns-wort | Tansy Ragwort | Yellow Starthistle | Yellow Toadflax | Dyers Woad