Dreamcatcher Alpacas
Plant safety · Toxic

Is White Snakeroot Poisonous to Alpacas?

White Snakeroot (Ageratina altissima) — a wild plant. Here is what alpaca owners need to know.

Updated 2026-10-02By the Dreamcatcher Alpacas editorial team
!

Yes — white snakeroot is toxic to alpacas.

Keep it out of pastures, hay and reach of fences, and never feed trimmings.

White Snakeroot (Ageratina altissima)
White Snakeroot (Ageratina altissima). Photo: Sten Porse, CC BY-SA 3.0 via Wikimedia Commons.
Status
Toxic
Scientific name
Ageratina altissima
Family
Asteraceae
Plant type
Wild plant
Toxic parts
Leaves and stems
Toxic compound
Tremetol
Region
Eastern North America

Why it matters

A woodland-edge plant of eastern North America; historically caused 'milk sickness' in people.

Signs of white snakeroot poisoning in alpacas

  • Trembling (especially after exercise)
  • Stiffness, weakness, reluctance to move
  • Constipation
  • Death

Signs can appear within minutes (cyanide, cardiac toxins) or only after weeks of exposure (liver toxins). Many poisoned camelids are simply found dead, so prevention is everything.

What to do if your alpaca ate white snakeroot

  1. Move the herd away and remove any remaining plant material, clippings or fallen leaves.
  2. Call your veterinarian immediately, even if the alpaca looks normal. Say what was eaten, roughly how much and when.
  3. Bring a sample or clear photo of the plant to help identification.
  4. Do not give home remedies, oils or try to make the alpaca vomit unless your vet tells you to.
  5. Keep the animal quiet, in shade or shelter, with water available. Write down the time and every symptom you see.
  6. Check every other alpaca that had access, then remove the plant permanently (including roots).

Emergency: call your veterinarian immediately. If you cannot reach them, contact an animal poison control service (in the U.S., the ASPCA Animal Poison Control Center or Pet Poison Helpline; fees may apply). Bring a sample or photo of the plant.

About the plant

Ageratina altissima, also known as white snakeroot, richweed, or white sanicle, is a poisonous perennial herb in the family Asteraceae, native to eastern and central North America. An older binomial name for this species is Eupatorium rugosum, but the genus Eupatorium has undergone taxonomic revision by botanists, and some species once included in it have been moved to other genera.From Wikipedia — “Ageratina altissima”, licensed under CC BY-SA 4.0.

Where it grows

Main range of concern: Eastern North America. GBIF, the Global Biodiversity Information Facility, holds 65,890 recorded observations of Ageratina altissima (L.) R.M.King & H.Rob. worldwide, including 58,393 in the United States. It belongs to the Asteraceae family, together with Cocklebur, Common Groundsel, Rayless Goldenrod, Tansy Ragwort, Burdock. See the occurrence map on GBIF.

Frequently asked questions

Is white snakeroot poisonous to alpacas?
Yes. Yes — white snakeroot is toxic to alpacas. A woodland-edge plant of eastern North America; historically caused 'milk sickness' in people.
What part of white snakeroot is toxic to alpacas?
Leaves and stems.
What are the symptoms of white snakeroot poisoning?
Trembling (especially after exercise), stiffness, weakness, reluctance to move, constipation and death.
Is dried white snakeroot safe?
Drying does not reliably make poisonous plants safe. Treat dried leaves and contaminated hay with the same caution.

Keeping pastures safe

  • Walk every paddock and fence line each season and remove toxic plants, including roots.
  • Never throw garden, hedge or lawn clippings over the fence.
  • Check pastures after storms for fallen branches (cherry, red maple).
  • Buy hay from known sources and inspect it for weeds.
  • Keep pastures well managed — hungry alpacas eat plants they would normally avoid.

Browse the full toxic plant checker, the printable list of poisonous plants and the list of safe plants.

This page is educational and does not replace advice from a veterinarian who has examined your animals. Camelid medicine uses many drugs “extra-label”, so dosing must come from your vet. In an emergency, call your vet first. Read our disclaimer · How we write and review content.

Data: plant status compiled from veterinary toxicology references (see sources); taxonomy and occurrences from GBIF; identifiers from Wikidata Q3271463.