Horsetail in hay

Help Support CattleToday:


Well-known member
May 9, 2004
Reaction score
NW Oregon
Just bought some hay and notice a few bales that I loaded out of the pasture had some horsetail in it. Naturally it is dried out and 95% of the leaves (needles) are off of it, just leaving dried stems. I know it is toxic to livestock, but how much of a concentration of horsetail needs to be in the hay to harm livestock?

Finaly found a decent answer on the internet (ask Jeeves). Horse tail is fern and here's what I found.... I was pretty concern about it so it had my attention, I have found very little of it in about 20 60lb bales. here's what I found;

In animals, the ingestion of horsetail produces muscle weakness, ataxia, weight loss, abnormal pulse rate, cold extremities, and fever. These symptoms are similar to those seen in nicotine intoxication. Hay composed of 20% or more E. arvense produced these symptoms in 2 to 5 weeks. 9

If you have anything to add thanks,
Forget what I ask in the last post I found a picture of horsetail and its not the same as what we call marestail . I was starting to get concerned cause I have a pasture that has a lot of what we call marestail