Frequently (and not so frequently) Asked Questions
BRIEF: Why are alfalfa and Tall fescue on the list of poisonous plants?
QUESTION:
I was trying to look up Poisonous plants for horses. On this list Alfalfa
and Tall Fescue are listed and I know horses eat these. why are they on this
list? I was also wondering if either Crepe Myrtle or Bradford Pear trees are
poisonous to horses.
ANSWER:
Fresh alfalfa pasture can cause bloating in cattle and some say that when
frozen, can cause problems for horses, too. At any rate, a diet made up of
only pure alfalfa has far too much protein and calcium for any but the fastest
growing and most pregnant of horses anyway.
Tall fescue has a variety of toxins derived from both endophytic fungi and
perhaps some parasitic ones that interfere with thermoregulation and
reproduction. This is widely known, stockmen use it anyway and watch out for
signs of too much in too hot weather. They have also bred endophyte varieties.
Bradford pears are not good because the leaves contain cyanide. I don't know
about Crepe myrtle.