Pest control refers to the regulation or management
of a species defined as a pest,
usually because it is perceived to be detrimental
to a person's health, the ecology or the economy.
Pest control is at least as old as agriculture. In
order to maximize food production,
it is advantageous to protect crops from competing
species of plants,
as well as from herbivores competing with humans.
The conventional approach was probably the first
to be employed,
since it is comparatively easy to destroy weeds by
burning them or plowing them under,
and to kill larger competing herbivores, such as crows
and other birds eating seeds.
Techniques such as crop rotation, companion planting
(also known as intercropping
or mixed cropping), and the selective breeding of
pest-resistant cultivars have a long history.