Locoweed - Toxic to Horses

Locoweed a Poisonous Plant Toxic to Horses

Locoweed is a common name for plants which fall into two genera; Astraglus and Oxytropis.

While there are hundreds of species of locoweed, only about 20 are considered poisonous.

These plants range from low growing ground covers to two foot tall clumps of flowers.

They can be found throughout the west from Canada to Mexico in semi-arid foothills and plains.

Locoweed - Toxic to Horses

Some species of locoweed are very similar to each other.

Even experienced botanists can have difficulty differentiating between a poisonous and non-poisonous specimen.

Horses typically avoid locoweed, but once they have sampled it a few times, they can become addicted to it.

They have to graze on it for a period of time before symptoms appear and the most obvious symptoms may not appear until well after the horse has stopped eating it.

Symptoms include …

  • altered gaits
  • aimless wandering, sometimes in circles
  • impaired vision, bumping into things
  • erratic behavioral changes
  • appear listless or complacent
  • wildly over-reacting to unexpected events

Locoweeds can have such a high alkaloid content that one Nevada species even poisoned the bees that were pollinating the plants.

Alkaloid poisoning has a cumulative effect which can be absorbed over long periods of time until symptoms appear and the effects in many cases are irreversible.

NOTE!! Horses found eating locoweed who have then been confined away from the plants prior to showing advanced symptoms, and who have been fed good quality hay and feed, have experienced a slow but successful recovery.