When Bad Plants Happen to Good Horses

This morning I went out to feed my two wonderful horses and discovered that they were not where I had left them. They weren’t loose. They (and by they I of course mean Poppy) simply took down two of the top split rails and put them neatly on the other side of the fence before stepping over the remaining one into their dirt paddock. Once they were in their dirt paddock they must have discovered that a) there is no grass and b) getting back over the fence again would be too much work, so they settled for snacking on the enormous tomato plant that was growing outside the goat’s stall. This is all that remains of that unfortunate tomato plant, who has been minding his business all summer long until two idiots decided to come up and eat him.

All of this would be all fine and good and a little bit amusing, if the tomato plant wasn’t in the nightshade family. Nightshade, as some of you may or may not know, is deadly toxic to horses.

Obviously Darwin has gotten bored with the regular ways of trying to kill himself (colic, choke, colic, colic) and thought this would be a new, FUN way for his mom to spend even MORE money on him. Right now Darwin is resting comfortably in his stall. He’s opening and closing his mouth, banging his head on the wall, and rolling his eyes, but this is normal behavior for him, so at the moment (knock on wood, knock on wood!) I am hoping the tomato plant will just pass through his system. This does, however, bring up an interesting point: if I had not known that the tomato was a member of the nightshade family, and that nightshade is deadly to horses, I might not have been keeping such a close eye on Darwin and Poppy and they might, even now, be in the throes of a very uncomfortable colic (I just checked on them five minutes ago – they are both munching hay and have drank the regular amount of water; I’ll go back down in another thirty minutes to check again).

All of this raises one simple question: What plants can kill your horses?

NIGHTSHADE: All parts of this plant are deadly to people and pets (horses included). They are in the same family as the tomato, potato, and pepper. Symptoms of poisoning include colic like symptoms, disorientation, loss of muscle control, dilated pupils, and death.






BUTTERCUPS: No, this is not a typo. Buttercups are poisonous to horses. Under normal circumstances horses will not eat them, but if they have nothing else to eat they may get a little hungry and try them out. Buttercups cause irritation around the mouth, colic, and diarrhea.






BRACKERN FERN: While not commonly found in pastures, brackern fern is all through the woods and I’ve been on a horse who has snatched a mouthful of them up before. If it is baled into the hay and digested by a horse it can be toxic. Symptoms of poisoning include loss of coordination, decreased heart rate, weight loss, staggering, and death if not treated.





MILKWEED: Living and dry plants are toxic to horses and while a horse will rarely eat milkweed on their own, it is often found in hay. Signs of poisoning include disorientation, loss of muscle control, rapid or weak pulse, and respiratory paralysis. Milkweed is rarely causes death.







RED MAPLE: The wilted leaves of the red maple produce cyanide. These are one of the few poisonous plants that I have found horses will eat even when they have grass. Symptoms include lethargy, dark urine, dark gums, rapid pulse, and increased respiration.






Some other poisonous plants include: red oak, st. john's wart, meadow saffron, robinia, laburnum, water hemlock, lupin, foxglove, white snakeroot, buckwheat, tall fescue, sweat pea, oleander, rhubarb, and black locust. For a great comprehensive list of poisonous plants compiled by the ASPCA click HERE.

Diligent pasture maintenance will keep your horse from ever having to encounter these potentially deadly plants and it is always a good idea to check with your hay provider and to give your hay a good once over before chucking it in the stall. If you suspect your horse ingested something he or she shouldn't have, the best course of action is to simply call your vet.