Pet Care

Field Horsetail

Additional Common Names:: Scouring rush, Common horsetail, Western horsetail
Scientific Name:: Equisetum arvense

Family:: Equisetaceae
Where Found:: Found throughout North America and Europe. Prefers moist, cooler areas along ditches, in moist meadows and in disturbed soil areas.
Toxicity:: Toxic to Horses
Toxic Principles:: Thiaminase
Clinical Signs:: The plant is commonly ingested when horses have very little suitable vegetation to graze on; ingestions over several days or weeks may result in adverse clinical effects. The toxic component breaks down thiamine (an essential nutrient for central nervous system function and metabolism). Clinical signs include weight loss, central nervous system disorders, muscle weakness gradually progressing in severity, convulsions and death.

If your pet ingested this plant, contact your local veterinarian or the ASPCA Animal Poison Control Center at 888-426-4435.*

* A $65 consultation fee may apply.