Toxic Parts:
all, especially the seeds
pyrrolizidine alkaloids nitrates
Flower Color:
  • flower color
  • flower color
meadows, haybales

Time of Greatest Risk


Geographical Distribution

Fiddleneck distribution - United States

Related Species


Amsinckia menziesii

Tarweed, Yellow Burrweeds, Amsinckias
6/ 10
Fiddleneck (Amsinckia menziesii) is one of several species of Amsinckia, which are annual broadleaved or short-lived perennial plants that are native to the Americas. Young fiddlenecks appear as rosettes, which develop into upright or semi-upright stems as it matures.

Fiddleneck Toxic Components

All parts of the fiddleneck plant contain pyrrolizidine alkaloids (PAs). If fiddleneck plants are ingested over a period of time, it can cause horses to develop pyrrolizidine alkaloid toxicity, which can lead to liver failure. Clinical signs usually don't become apparent until months or sometimes up to a year following ingestion of the plant.

What Fiddleneck Looks Like

  • Stems: Can reach up to 4 ft (1.2 m) in height and are covered in soft to long stiff hairs. They can be branches or unbranched.
  • Leaves: Lance-shaped, coarse, hairy, and with pointed tips. Spaced alternatively on stems.
  • Flowers: Have distinctive flowering heads which coil up in a cluster like a fiddle's neck, and form on top of spikes. Flowering occurs from late winter through the spring.


  • Appetite Loss
  • Depression
  • Colic
  • Jaundice
  • Behavioral Changes
  • Frequent Yawning
  • Photosensitvity
  • Loss Of Condition
  • Head Pressing
  • Diarrhea
  • Weight Loss
  • Incoordination
  • Aimlessly Wandering
  • Awkward Gait
  • Actively Pushing Against Fences And Biting The Ground


MECHANICAL CONTROL: Hand pulling is effective but usually populations are too dense for this to be practical. Mowing before seed production can reduce seed set and will be somewhat effective. Tillage is effective in cultivated areas.

CHEMICAL CONTROL: Chemical control can be difficult due to the hairs on the plant and must be done prior to seed production.