Notes to broadcasters
Content: An insect is a pest when the amount of damage it does to your plants justifies spending money to control it.
What does the word “pest” mean to you? Many farmers think that all insects are pests.
Here is a different idea about pests. An insect becomes a pest only when it damages enough of your crop to make you lose money. It is at this time when you should consider using a pest control method.
Let’s think about what this means.
Imagine that there are some insects on your onions. They eat three onions. Imagine that these three onions are worth one dollar in the market. So the insects are eating one dollar of your profit. If they are eating one dollar of your profit, it does not make sense to spend more than one dollar to control them.
For example, it could cost you two dollars to spray chemicals on the onion field. You would spend two dollars to stop the insects from eating three onions that are worth a total of one dollar. So you would actually be losing money.
The point to remember is that just a few insect pests in the field cannot do much damage. Do not panic and think you have to spray with chemicals as soon as you see some insects in your field. There must be a certain minimum number of insects, causing a certain amount of damage, before they become a real problem.
Check the amount of damage the insects are doing and decide whether or not you can justify spending money to control them. It may not be too serious if you harvest a few damaged onions or cabbages; you can always keep these for your family to eat.
So now we have another way of thinking about when an insect is a pest. An insect is a pest when the amount of damage it does to your plants justifies spending money to control it.
This article is based on information presented in a course on Integrated Pest management by Hermogenes Castillo of ALTERTEC, Guatemala. ALTERTEC is a non‑profit, non‑governmental organization that works with farmers to promote integrated ecological agricultural systems.