Back to Target Weeds for Control
- Why should we care?
- Although it generally does not pose a threat to high quality areas, this plant colonizes primarily in disturbed areas such as pastures, roadsides, and ditch banks, as well as hayfields and disturbed prairies. The Plumeless Thistle is distasteful to most grazing animals, affecting available forage.
- How to Identify
- Biennial herbaceous plant, between 1.5 – 6 feet tall, muti-branched stem. Plants overwinter in the rosette stage. The leaves are alternate, coarsely lobed, dark green with light green midrib, with the underside of the leaves hairy. Large first year rosette leaves. The flowers are disk-shaped flowerheads threat contain hundreds of tiny individual flowers that are about one-third the size of the musk thistle’s flowers. They bloom from June through July. The roots consist of a fibrous taproot.
- About the Plant and Where it came from
- Carduus acanthoides
- This native of western Europe was introduced to the U.S. in the Early 1800s, and is declared an agricultural pest.
- How to Control
- Cultural control: Hand-pulling or mowing in early bud or bloom stage, then dispose offsite.
- Chemical control: Spot-spraying with lyphosate, triclopyr or metsulfuron when plants are in rosette stage (first year) in the fall when non-target plants are less susceptible.
- Biological control: Thistlehead-feeding weevil and rosette-feeding weevil.
Caution: Observations of weevils feeding on native thistles.