Frequently (and not so frequently) Asked Questions
BRIEF: How can I get rid of this horsetail (equisetum arvense)?
QUESTION:
I am wondering how to successfully rid my property of horsetail.
A neighbor of ours has a relative who works for Ortho Chemical and he did not
know of a chemical solution (to kill this plant)...which is not a good option
for us anyway as there is a pond with fish and wild birds (herons, wood
ducks, red-winged blackbirds) at one end of our property where this weed is
prevalent.
If we plow the fields under repeatedly where it is growing, will that
short-circuit its growing cycle? I know it likes 'poor soil'.
ANSWER:
Horses can often avoid horsetails well enough if there is plenty of
other feed and, therefore, they are not often poisoned by this plant in a
grazing situation. They are slightly more likely to eat ferns in a pasture,
but even there, poisoning in the presence of other good pasture is not too
common. Pteridophyte (ferns and horsetails) poisoning becomes a problem if
there is nothing else to eat, or (most common cause in the US) if pteridophytes
are cut and baled into hay. Hays containing 20% horsetail or bracken fern will
result in thiamin-deficiency symptoms in 2-5 weeks. So, if you just have a few
horsetails in one end of a good pasture that you never cut for hay or overgraze,
you may get away with this. If you plan to cut it for hay or force the horses
to eat the pasture down low, then you might want to get rid of the horsetails,
or fence the horses out of that area and turn this wet ground over to the birds
and wildlife.
I am not an expert in weed control, but I think that if you want to get rid of
horsetails, then plowing (to get rid of underground plant structures) and a
good subterranean tile drainage system would help pasture plants out-compete
the horsetail. On drier ground, after a good plowing and a seeding with competitive
pasture plants, the horsetails will not be as plentiful, if they can grow at all.