Dreamcatcher Alpacas
Plant safety · Toxic

Is Johnsongrass Poisonous to Alpacas?

Johnsongrass (Sorghum halepense) — a grass. Here is what alpaca owners need to know.

Updated 2026-10-02By the Dreamcatcher Alpacas editorial team
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Yes — johnsongrass is toxic to alpacas.

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

Johnsongrass (Sorghum halepense)
Johnsongrass (Sorghum halepense). Photo: Daniel VILLAFRUELA., CC BY-SA 4.0 via Wikimedia Commons.
Status
Toxic
Scientific name
Sorghum halepense
Family
Poaceae
Plant type
Grass
Also known as
Johnson grass, johnson grass, great millet
Toxic parts
Young regrowth, frosted, wilted or drought-stressed plants
Toxic compound
Cyanogenic glycoside (dhurrin) and nitrates

Why it matters

Safe as well-cured hay in many cases, but fresh regrowth after drought, frost or cutting can release cyanide. Have suspect hay tested for nitrates.

Signs of johnsongrass poisoning in alpacas

  • Rapid, labored breathing within minutes
  • Bright cherry-red gums and blood
  • Anxiety, trembling, staggering
  • Convulsions and collapse
  • Death within 15 minutes to a few hours

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 johnsongrass

  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. Cyanide poisoning moves fast — your vet may have a specific antidote, so speed matters more than anything.
  4. Bring a sample or clear photo of the plant to help identification.
  5. Do not give home remedies, oils or try to make the alpaca vomit unless your vet tells you to.
  6. Keep the animal quiet, in shade or shelter, with water available. Write down the time and every symptom you see.
  7. 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

Johnson grass or Johnsongrass, Sorghum halepense, is a plant in the grass family, Poaceae, native to Asia and northern Africa. The plant has been introduced to all continents except Antarctica, and most larger islands and archipelagos. It reproduces by rhizomes and seeds.From Wikipedia — “Johnson grass”, licensed under CC BY-SA 4.0.

Where it grows

GBIF, the Global Biodiversity Information Facility, holds 70,846 recorded observations of Sorghum halepense (L.) Pers. worldwide, including 24,427 in the United States. It belongs to the Poaceae family, together with Cheatgrass, Corn Plants & Stalks, Dallisgrass (ergot-infected), Foxtail Barley & Foxtail Grasses, Perennial Ryegrass. See the occurrence map on GBIF.

Frequently asked questions

Is johnsongrass poisonous to alpacas?
Yes. Yes — johnsongrass is toxic to alpacas. Safe as well-cured hay in many cases, but fresh regrowth after drought, frost or cutting can release cyanide. Have suspect hay tested for nitrates.
What part of johnsongrass is toxic to alpacas?
Young regrowth, frosted, wilted or drought-stressed plants.
What are the symptoms of johnsongrass poisoning?
Rapid, labored breathing within minutes, bright cherry-red gums and blood, anxiety, trembling, staggering, convulsions and collapse and death within 15 minutes to a few hours.
Is dried johnsongrass 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 Q858360.