How Dangerous Are Buttercups?

Buttercups appear harmless to most. Their delicate petals are a cheerful yellow color. Don't let their pleasant appearance fool you though! They can be very toxic to horses, especially when eaten fresh and in large amounts. With symptoms varying from blisters in the mouth to colic and even seizures, buttercups are not to be ignored! If your field is covered in them, then it's time to eliminate these flowering weeds.

Toxicity of Buttercups

Ranunculus, also known as buttercups, are often found in pastures. They're a bright yellow color. In many species of the plant, the leaves and stems contain ranunculin. When chewed and crushed, a toxic blistering agent called protoanemonin is created. It's a bitter-tasing oil that will irritate your horse's mouth and gut. Unfortunately, these plants are found all across North America. They can grow in clay, damp sand, gravel, marshes, and swampy meadows. Buttercups thrive in wet soils!

Symptoms of Buttercup Toxicity in Horses:

• Blistering on the lips
• Excessive salivation
• Swelling in the face
• Colic
• Diarrhea
• Convulsions
• Skin twitching

In extreme cases, death can even occur!

The toxicity will vary depending on the growing conditions, freshness, and age of the plant. Generally, the early flowering stage is most dangerous. This can occur April through August. Buttercups found in hay are not as risky because the toxic oil evaporates once the plant is cut. Most horses will not eat fresh buttercups if they have other forage to eat. The bitter taste warns them away. They may consume it if the fields are sparse and overgrazed. Other livestock like cattle, goats, and pigs are also at risk for poison.

To ensure you're dealing with buttercups and not another plant, invite your local agricultural extension agent out for a visit. They should also be able to recommend how to control them, such as through tilling or spraying. Multiple herbicide applications may be necessary. Ideally, you should prevent your pastures from being overgrazed.