Agriculture Reference
In-Depth Information
Using Herbicides
It is difficult to control weeds chemically in a legume/grass hay field or pasture, as many of
the herbicides would kill the desirable plants as well as the weeds. Herbicides can be used
very effectively, however, in grass pastures. You will need to choose a selective herbicide
specifically for your situation. Try to control weeds by other means, but if you must use
herbicides, carefully monitor every step or you could ruin your pasture or harm the envir-
onment.
DISEASE AND INSECT CONTROL
Bacterial, viral, and fungal diseases and some insects can affect plant yield and may kill the
entire field. The selection of the appropriate variety of hay or grass for the local growing
conditions is often the best preventative. Genetic research has provided us with varieties
that are resistant to specific diseases and pests.
Particularly in the Southwest, second-cut or later alfalfa hay that has gone to bloom may
contain blister beetles, which can be lethal to horses. The toxin in these insects, canthar-
idin, is so deadly that just a few beetles, dead or alive, can kill a horse. If you live in an
area where blister beetle poisoning has been reported, confer with your county Extension
agent for assistance in identification of the beetles and purchasing certified blister-beetle-
free hay.
Predator insects such as wasps, praying mantises, and ladybugs have been used success-
fully to kill aphids and grubs. In most cases, if your climate will support these predator
insects and their prey in the field, the predators will show up on their own. Introduction of
predator insects is usually not needed.
RODENT AND SNAKE CONTROL
Rodents, including mice, gophers, rabbits, ground squirrels, and groundhogs, can present
problems in a pasture or hay field. First, their holes can pose a threat to your horses as they
gallop across the pasture. Second, the mounded dirt from their burrows can end up in your
baled hay. In addition, rodents can carry dangerous diseases, and a large population can put
a real dent in the forage production of your field. Depending on your situation, it might be
impossible or undesirable to try to eradicate rodents completely, but you can keep them un-
der control by keeping a couple of cats and dogs on your acreage and allowing them access
to the problem fields. Natural predators of rodents are hawks, owls, coyotes, and snakes.
