Plants Horse Owners Should Protect Their Animals From

Marike Stucke Freelance Author

June 23, 2026, 11:03 am | Read time: 4 minutes

Horses don’t just eat grass in the pasture. Among the blades, plants can grow that cause severe poisoning and, in the worst case, can even be fatal. PETBOOK reveals which types are particularly dangerous and how owners can recognize them.

Toxic Pasture Plants for Horses: An Overview

The right feed, a good veterinarian, regular exercise, and contact with other horses and humans: The list of what horses need for a long and healthy life is extensive. But even if horse owners or those with a riding share put great effort into these points, it is all for naught if toxic plants are present in the horse paddock. These can lead to serious illnesses or even death after consumption. Therefore, special caution is always required. The wrong plant can be eaten faster than one might think.

There are many types of plants that can be toxic to horses. Toxicity can vary depending on the plant and amount, but it is important to know which plants grow in the pasture and which should be removed. Here are some of the best-known toxic pasture plants.¹ ²

Monkshood (Aconitum)

Also known as wolfsbane or blue monkshood, this plant is extremely toxic to horses. Even small amounts can lead to severe poisoning symptoms.

Monkshood in bloom (Aconitum napellus) — Small amounts of blue monkshood can be fatal

Ivy (Hedera helix)

Ivy is toxic not only to horses but also to other animals. Consumption can cause gastrointestinal issues, respiratory problems, and neurological issues.

Climbing ivy — Ivy often causes digestive problems in horses

Spindle Trees (Euonymus)

The parts of these shrubs contain substances that can lead to heart problems and colic in horses.

Spindle tree with red flowers — Poisoning can lead to circulatory issues

Buttercup (Ranunculus)

Buttercups, also known as crowfoot, are found in many pastures but are toxic to horses. Consumption can lead to gastrointestinal irritation and problems.

Buttercups in a meadow — Buttercups can cause diarrhea in horses

Autumn Crocus (Colchicum autumnale)

This plant contains the toxic alkaloid colchicine, which can cause respiratory issues, colic, and heart problems in horses.

Purple blooming autumn crocus — In dried form in hay, easily confused with other harmless herbs

Deadly Nightshade (Atropa belladonna)

Deadly nightshade is extremely toxic and can lead to severe neurological symptoms in horses.

Deadly nightshade branch with dark berries — Even small amounts of deadly nightshade are harmful

Common Hogweed (Heracleum sphondylium)

The sap of this plant can cause skin irritation, especially if the skin is subsequently exposed to sunlight.

Common hogweed growing in a meadow — Can cause swelling upon skin contact

Poison Hemlock (Conium maculatum)

Poison hemlock is extremely toxic and can cause respiratory issues, seizures, and death in horses.

Blooming poison hemlock — Can be mistaken for common hogweed

Ragwort (Jacobaea vulgaris)

This plant is often found in pastures and frequently leads to poisoning. It can cause liver damage, colic, severe weight loss, and apathy.

Ragwort with yellow flowers in a meadow — Ragwort often causes colic in horses

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How to Recognize Toxic Pasture Plants

Knowing the plants in your pasture can prevent accidental consumption by your horse.

Know what’s growing: What plants grow in the pasture during which season? Familiarize yourself with the locally common toxic plants.
Observation: Especially in spring and summer, at the start of the growth and flowering period, regularly check your pasture for the presence of unusual or suspicious plants.
Identification books and apps: There are identification books and mobile apps that can help identify plants in the pasture. With an uploaded photo, plant apps can usually accurately determine the plant and its toxicity.
Consultation with experts: If you are unsure whether a plant is toxic, consult a specialist, such as a plant expert. They can walk the pasture with you and check for toxic plants.

Also of interest: Well-intentioned but deadly! Why feeding horses is prohibited

What to Do if Toxic Plants Grow in the Pasture

The first action should always be to remove the plant in question. However, sometimes these are so widespread or keep sprouting that they continue to pose a threat to the horses. In this case, the only solution is to fence off the affected area of the pasture and extensively dig up the soil. Now the plants can be removed along with the roots.

It is also important to prevent toxic plants from spreading further in the pasture through their seeds. If toxic plants grow near the pasture edge, they should also be removed before they bloom.

Other riders and stable helpers should also be informed about the presence of toxic plants and know what they look like.

This article is a machine translation of the original German version of PETBOOK and has been reviewed for accuracy and quality by a native speaker. For feedback, please contact us at info@petbook.de.