Poisonous Plants For Horses

Poisonous Plants For Horses

There are several plants that are poisonous to horses and you could find them growing in and around your fields or stables. Poisonous plants will also crop up on trails when you are out and about. Here are the species to look out for:


Ragwort tastes bitter and so horses won't generally eat this plant whilst it is growing. But it does become more palatable when it is wilted or has died. The toxins in this species cause liver failure and so hay should never be made from fields which contain Tagwort. As little as 1kg of ragwort consumed over a horse's life can prove fatal. Ragwort thrives on wasteland and poor pasture. Each plant produces an enormous number of seeds which are quickly spread far and wide by the wind. The plant takes 2 years to fully grow and to produce its bright yellow flowers. Ragwort should be uprooted, removed and burned. Mowing and cutting will simply cause the plants to grow back more quickly.


Horses do not find these flowers palatable but the plants are tastier when cut and in hay. It is easy for a horse to accidentally consume foxgloves and just 100g of plant matter could prove fatal. It is vital to ensure that foxgloves do not accidently find their way into any hay on your property or at the yard.

Deadly Nightshade

Consuming this plant rarely proves fatal for horses but can lead to unconsciousness and convulsions.


Buttercups are poisonous to horses if eaten fresh, but a horse would need to consume a huge volume of the plants for them to cause any serious damage. Dried buttercups are harmless and so do not need to be eliminated from hay.


There are always plenty of acorns around during the autumn and horses love them. Sadly, acorns can lead to colic and poisoning if eaten in large enough quantities. Play safe and clear acorns from your pastures or move horses to areas away from oak trees. .


Yew is a common tree in domestic gardens. The plant, leaves and berries are all poisonous to horses and in relatively small quantities. As little as 0. 5kg of plant material can prove fatal so watch out for leaves and berries which could be blown into your field.


Another common plant used for hedging, privet is highly toxic for horses, even in small quantities. Remain alert as some people are given to dumping hedge clippings in fields.


A highly toxic plant to horses, rhododendrons cause failure of the respiratory system. Horses wouldn't usually choose to eat these flowering shrubs but you never know!

Sycamore, Maple and Acers

Both the seeds and the saplings of these trees contain Hypoglycin-A which causes atypical myopathy in horses. Symptoms include muscular stiffness, muscle tremors, sweating, depression, high heart rate and dark urine. Horses appear weak and lethargic but may retain their appetites.


Horses will usually avoid eating bracken ferns but some animals develop a taste for them. The plant is only harmful if eaten in large quantities and over a period of weeks. Bracken poisoning can result in nervousness, circling, staggering, muscle spasms, blindness and convulsions. Always seek advice from your vet if you suspect that horse has eaten poisonous material or if they are suffering mysterious symptoms and you can't rule poisoning out.

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