Agronomist notebook: Dos and don’ts of pesticide use

A man applies pesticides to crops. The right type of equipment for spraying should be considered during this exercise, which include the right nozzles. Separate knapsacks should also be used for herbicides, insecticides and fungicides. FILE PHOTO | NMG

What you need to know:

  • To begin with, before buying any pesticide, know the target pest or disease and explore other methods of crop protection such as handpicking pests or crop rotation.
  • Check the batch number, registration number, date of manufacture and the expiry date. The pesticides or bio-pesticides dealer should be registered and have a valid licence.
  • Despite having a spray programme before spraying, always scout for pests and diseases. Keep records for the scouting, spraying and environmental conditions when the exercise is done.
  • Perforate the chemical containers so that they are not used for any other purpose. The knapsacks should also be thoroughly cleaned and rinsed.

The rise in pests and diseases has seen many farmers rely heavily on chemicals to save their crops.

However, as much as the pesticides help control the pests and diseases, farmers should be careful while using them since they are harmful to human health.

My visit to various smallholder farms in my line of duty indicates that a good number of farmers use pesticides, but they do not adhere to recommended guidelines.

This article highlights the various mistakes farmers make while using pesticides and offers possible solutions
To begin with, before buying any pesticide, know the target pest or disease and explore other methods of crop protection such as handpicking pests or crop rotation.

Then when buying, ensure that the pesticide container is sealed and do not purchase more than what you require during the season. Storing opened pesticides results in reduction in effectives of some of the chemicals or sometimes they expire.

Read the instructions accompanying the chemicals carefully, both primary and the secondary labels, before purchasing.

Check the batch number, registration number, date of manufacture and the expiry date. The pesticides or bio-pesticides dealer should be registered and have a valid licence.

While transporting the pesticide, the farmer should ensure they do not contaminate any other product.

Chemicals should be stored originally in containers that are tightly closed and labelled. Store herbicides, pesticides and fungicides separately, like on different shelves away from children, livestock and protected from the direct sunlight.

Before opening the container, the farmer should always read the label and purpose to use the chemical on the specified crops.

Despite having a spray programme before spraying, always scout for pests and diseases. Keep records for the scouting, spraying and environmental conditions when the exercise is done.

The pre-harvest and re-entry interval of each chemical should be observed before harvesting the produce or working in the same fields.

Always wear protective gadgets like overalls, gumboots, gloves and respirators before spraying.

OBSERVE WITHDRAWAL PERIOD

While applying the pesticide, the farmer should avoid smoking, eating or drinking and use clean water to mix the chemical. Mix the required quantity as using pre-mixed chemicals after 24 hours reduces effectiveness.

The right type of equipment for spraying should be considered, which include the right nozzles. Separate knapsacks should be used for herbicides, insecticides and fungicides.

Spray the chemicals on a cool and calm day preferably in the morning or evening before temperatures rise but this also depends with the target pests.

Use the right quantities of chemicals as excessive use results to pollution and the pest develops resistant increasing the cost of production.

Supposing you spray excessively a pesticide on the crops, well it will depend with the chemical but in most cases it’s difficult to reverse. However, one can increase the frequency of irrigation.

Rinse your eyes with adequate running water for about 10 minutes in case they come into contact with pesticides and seek medical attention in case there is persistent irritation. To curb resistance, use chemicals with different active ingredients or molecules.

After spraying, one should remove the protective gear and wash them separately from other clothes.

Perforate the chemical containers so that they are not used for any other purpose. The knapsacks should also be thoroughly cleaned and rinsed.

Drink plenty of water to avoid dehydration after spraying and wash your hands thoroughly before drinking or eating.

Drinking milk after spraying is just a way of getting the energy but ideally one should drink adequate water to clean up the blood system.

After spraying, always observe the withdrawal (pre-harvest interval). This differs from different crops and chemicals. Some have three days others seven or even 14 days.

Lastly, do you need to hire someone to spray your crops. This depends with the farmer since some people are allergic to chemicals and a pregnant woman should not spray. Also, if you don’t know spraying techniques, hire somebody.