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Publication - 66
Pest Control In Gardens and Homes
- Pesticides Task
- Westmount Post
- P.O. Box 117
- Westmount Québec
- H3Z 2T1
Why is this pamphlet
- There is much
misinformation about pests, pesticides and their
- You cannot rely
on others (governments, pesticide sales people, etc.) to
protect you from danger.
- This pamphlet
will provide you with correct information and empower you
to make responsible decisions.
- Pests comprise
relatively few species.
misinformation, people believe that most insects are
harmful, whereas only 0. l % are pests, 99.9% being
neutral in their effects or essential to our survival as
pollinators, decomposes, regulators of pests, and as food
for other beneficial animals such as many fish and birds.
- Pests are not the
causes of problems but rather the symptoms of badly
designed, mismanaged or malfunctioning gardens, farms,
forests, etc. Hence the solution is to correct their
design and management, taking direct actions against
pests only in emergencies.
- Many organisms
are regarded as pests only because of current
"fashions" that cannot be justified in terms of
health or well-being, e.g., our desires for cosmetically
perfect fruits and vegetables and weed-free lawns.
- Many weeds in
lawns are indicators of unbalanced or compacted soils.
Removing the weeds annually will not correct the
underlying causes which, if not dealt with, will
ensure that the problem will recur.
include fungicides, herbicides, insecticides, miticides
and other biocides that are used to reduce the number of
- Although the
first two groups are slightly specific, insecticides and
miticides are nonspecific chemicals that are as poisonous
to beneficial organisms as they are to the pests; and all
are poisonous to people and pets.
- Most harmful side
effects of pesticides are not immediately apparent
because they are sub-lethal, and may be delayed.
- These effects are
aggravated by the tendency of pesticides to persist in
- As the pesticide
disperses and breaks down, the pests return, and
sometimes new pests are created due to the poisoning of
their natural enemies.
- Eventually all
pests become resistant to the materials use against them.
- Despite these
problems pesticides have become an essential part of our
food and fibre production systems, partly because of
their "magical bullet" image and ability to
give quick results, and because their harmful effects
rarely enter into the cost-benefit analyses.
- As we become more
aware, responsible, and take info account long-term
effects, it is likely that this heavy reliance on toxic
chemicals will gradually be replaced by safe
alternatives, and pesticides will only be used in an
emergency or as a last resort.
- Alternatives to
pesticides, rather than focusing on the elimination of
"enemies", aim to achieve satisfactory control
and prevention at comparable or lower costs, while
minimizing risks to the environment and humanity. Instead
of relying on single, simple, quick solutions such as
pesticide use, they generally involve taking several
combined actions, some of which do not need to be
- These include
cultural, physical, chemical, biological and ecological
for behaving wisely is yours. This includes thinking
about the short and long-term effects of what you
do on yourself and your family, your neighbours, and on
other organisms and future generations. While experts can
give you advice, only you are responsible for your
actions. Thus, we need to think differently about pests
and take different types of actions to prevent and
- Often people
mistakenly believe that any product that can be purchased
in a store is safe, or that they are protected by
governments and regulatory agencies. Because of the
short-term tenure of governments and the economic
constraints in which they operate, acceptable levels of
safety are often determined in relation to profitability
and commercial pressures. You do not have to make this
- To act wisely,
however, you must become familiar with the facts and be
willing to make approaches to solving problems that may
differ from the majority in society who may be less
knowledgeable or aware than yourself.
HAVE A PEST PROBLEM
The presence of an
insect or weed does not necessarily mean that it is a pest. It is
normal to have a few of these organisms around; indeed, their
absence would be cause for alarm. So the first thing we need to
change to is our expectations of what is normal.
- It is only when
these organisms become unusually abundant that we need to
examine the situation to find the causes and take
- In most cases the
problem can be traced to something inappropriate that we
did, such as over-fertilizing, planting at the wrong time
or in an unfavourable location; or it may be due to
natural deficiencies within our soils, or because of a
lack of natural controls.
- Responding to
these causes requires us to learn about the pest and
about the way it is likely to respond to different
conditions that discourage potential pests.
PREVENT AND CONTROL PESTS WITH MINIMAL RISK
- The key to pest
prevention in the garden or lawn is healthy soil, healthy
resistant plants, appropriate planting designs and
careful environmental management.
- Most soils require
the regular addition of organic matter, such as
compost, to remain healthy.
- The soil can be
loosened but it should not be cultivated in such a way
that its surface layers become buried under the deeper
layers because this will kill most of the beneficial
- By following
these rules we can create ideal food and space conditions
for decomposers and their predators. These beneficial
soil organisms will then be able to prevent the
development of root diseases, and some of the predators
will feed on the plant pests.
- Choose plant
varieties that are resistant to local pests and diseases.
- Arrange planting
times so that they don't coincide with the occurrence of
potential pests, e.g., by delaying planting carrots by
two or three weeks, attack by carrot rust fly can be
- Minimize stress
to plants when transplanting, and provide optimum
conditions for seeds. This creates strong plants that are
most able to resist and recover from pest attack. Rotate
annuals, e.g., soil improving crops such as legumes
(peas, beans and clovers) are followed by heavy feeders
(tomatoes, corn, potatoes) and then light feeders
(carrots, lettuce, beets, onions).
planting can be used to discourage or control some pests.
Onions and carrots planted together to repel one
another's major pests, and the smell of herbs and flowers
may prevent the pests from finding their favourite hosts.
- Having plants
with small flowers (e.g., parsley, dill, Queen Anne's
lace, lovage) in the garden throughout the year will
attract small insects that will parasitize and kill many
- Some of these
beneficial insects can be purchased and released at
regular intervals as biological controls, but they will
only remain in the same area if the conditions are
- Commercial and
homemade traps can sometimes be effective in controlling
pests. Earwigs can be killed by trapping them in skewed
up newspaper stuffed into flower pots placed upside down
on the ground at night and shaking them out into soapy
water in the morning. Hand removal of pests and diseased
parts of plants is another time tested remedy.
- Most caterpillars
can be killed by spraying them with a suspension
containing a bacterium called Bacillus thuringiensis, available
in several commercial formulations.
- You can make your
own pathogen spray by collecting several dozen insects
and placing them in a blender with a little water (use
rain water rather than tap water to avoid the chlorine),
sieve the resultant mixture and dilute it with several
times the amount of water, then spray it on the pests.
- Some of the least
persistent insecticides are the "botanicals",
which are made from plants (the most common is
pyrethrum); but as with all insecticides, these should be
used with great care and only as a last resort because
they also kill beneficial organisms.You can also use a
blender to make your own botanical pesticides from
different types of plants.
- This is one of
the many ways you can experiment and design your own
unique methods of control, but be careful to avoid using
toxic materials. Natural materials can be just as toxic
- To control
carpenter ants, earwigs, and stored food pests, use
diatomaceous earth. D.E. is a non-toxic powder that
scratches the wax off the insects body causing it to dry
up and die. This is particularly useful within a house or
other enclosed space. Place it in corners, on window
ledges and in dead spaces such as between walls and in
- In late summer or
fall remove the remains of annual plants so that they do
not provide overwintering sites for pests.
- An ideal way to
do this is to compost them. This disinfects them and
creates an ideal soil amendment at the same time.
- Soil should be
kept permanently covered with green (plants) or brown
materials (mulches and amendments). Bare soil encourages
erosion and loss of valuable nutrients, which in turn
creates favourable conditions for pest attack.
- Weeds in a lawn
should be controlled by creating conditions whereby the
grass can out-compete them, e.g. by setting the mower so
that the grass is cut at 6-7 cm. high or higher (i.e.,
higher than usual); removing any thick thatch; infrequent
deep watering; aerating the soil, particularly where
there is compaction; and adding balanced amendments, such
as sieved compost, usually in the fall.
- The main
preventative approach, however, is to create ideal
conditions for the grass prior to seeding it or laying
- If weeds are not
too plentiful or the area not too large, hand weeding may
provide a safe, short-term solution.
- If you have a
persistent pest problem, seek advice from an expert in
the use of safe methods of pest control, ideally one who
is not trying to sell you something.
- Only use
pesticides as a last resort. If you do decide to use
them, be sure that you are completely aware of the safety
precautions that must be taken, because knowledge is your
best insurance against mishaps. Most important of all;
read the label and follow the instructions exactly.
- One test is to
only use Pesticides if you can justify their use to those
you love most in the world, and to your children's
- Help others to
take a responsible approach to pest prevention and
control; and pat yourself on the back for acting
- Prepared by Dr.
Stuart B. Hill,
- Dept. of
Entomology and Ecological Agriculture Projects,
- MacDonald College
of McGill University
- Ste-Anne de
Bellevue, Quebec H9X IC0
- (514) 398-7771
Copyright © 1986 Ecological Agriculture Projects
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