I keep reading
about "IPM" or integrated pest management and am looking for a
succinct definition of that term. I read about
it in different contexts, but I am still a little confused about it
and how it works with plant pests.
A: Integrated pest management (IPM) is a
method of pest control that uses a variety of techniques to keep
pest populations at tolerable levels. IPM is not organic gardening,
but using IPM principles reduces pesticide use because it gives you
tools other than pesticides to manage pest problems. I like to think
of IPM as common sense pest control. A more technical definition is
that it is a way to manage pests in an environmentally and
economically sound manner.
Stinkbugs can be trapped instead of sprayed
Sometimes I think IPM is a little easier for farmers
and commercial producers to understand than it is for home
gardeners. If a farmer knows that a given pest will reduce the value
of his crop by $500, and it will cost him $300 to spray to control
the pest, then the farmer will likely choose to spray. It is
trickier for home gardeners, because they are rarely totally
dependent on their vegetable garden or fruit plantings. And when we
are talking about ornamental plants - trees, shrubs and flowers - it
gets even harder.
Again, a nurseryman or greenhouse grower will make
spray applications when damage from pests will reduce the value of
his crop. Once that tree, shrub or flower is growing in your yard,
it is more a matter of how much aesthetic damage you are willing
tolerate before you choose to spray.
IPM includes pest control tools such as:
controls such as making sure ornamental plants are suited to the
place in your yard where you intend to plant them. All plants
have certain preferences for sun or shade, amount of soil
moisture, soil pH and
fertility levels, and tolerance for wind
or deicing salts. Whenever those requirements are not met,
plants can be stressed and become more susceptible to insect and
disease problems. Once chosen, plants should be planted and
vegetable gardeners, cultural controls include routine crop
management practices such as tilling (to expose overwintering
insects); crop rotation and thinning overcrowded seedlings (to
allow good air circulation).
controls such as excluding pests with floating row covers
(Garden Blanket, Reemay) or picking insects off plants by hand.
controls available to home gardeners are mainly plants that are
resistant to common insect and disease problems. This is
especially important for trees and shrubs because they will be
part of your landscape for a long time, but it is also helpful
to grow vegetables that are resistant to common diseases.
controls include preserving populations of predatory or
parasitic insects that are present in your landscape. These
beneficial insects feed on or parasitize (and kill) insects we
consider pests. They are active in your garden unless you
regularly use broad-spectrum insecticides such as Sevin (carbaryl),
whether you notice them or not. Most people know lady beetles
and praying mantids, but there are a host of beetles, true bugs
and tiny wasps (they do not sting people!) that are beneficial.
Introducing purchased beneficial insects to your yard is not
always successful – they often fly away. Encourage beneficial
insects in your yard by providing a variety of blooming plants
so that something is in bloom from early spring until fall and
by avoiding broad-spectrum insecticides.
controls – pesticides – are applied when other steps are not
controlling the problem or on those occasions when the pest is
life threatening to a tree or shrub you prefer not to lose.
Emerald ash borer is a good example of the latter.
many options when it comes to pesticides. Pesticides run the gamut
from very safe products such as insecticidal soap and horticultural
oil to conventional pesticides.
Always spray the least toxic
In between are
those derived from plants or naturally occurring organisms such as neem oil and spinosad. They are soft in that they break down quickly
– often within hours of exposure to sun - and do not harm
beneficials coming into an area once they have broken down. However,
they should be treated with the same respect you would afford
conventional pesticides. Some pest problems, such as emerald ash
borer, are only controlled by applications of specific conventional