There is an ongoing debate about the danger of using agrochemicals on crops and weeds by farmers. Many claim that indiscriminate application of agrochemicals by farmers kills insects including innocent and even useful ones such as honey bees and other pollinators.
Crop production and generally propagation of plant life heavily rely on insect pollination. Some alarmist reports in the press are already forecasting a situation in which we will not have any insects and other organisms such as worms, rodents, and reptiles due to the continued use of pesticides, synthetic fertilisers, and herbicides.
In their view it will be like an ecosystem collapse. And the fear of losing all insects and a sizable amount of plants (both farmed and wild) has been gaining significance, with environment activists calling for immediate action to save the ecosystem and biodiversity. They blame it all on modern agriculture which heavily depends on chemicals to fight weeds and pests.
Ironically, the same activists also discourage the adoption of modern biotechnology (Genetic Modification Organisms technology) which makes it possible for some crops to be produced without the use of pesticides. If in Uganda we grew GMO Irish potatoes the farmers would not worry so much about pesticides expenses. GM cotton which is by far higher yielding, would be far cheaper to produce without pesticides.
Risks of using agrochemicals
However, it is also widely believed that it is impossible to practice gainful farming today without using agrochemicals. It is a lot easier and cheaper to fight weeds with herbicides than to use human labour. Some people use diesel powered mowers to control weeds but this is far beyond the affordability of most smallholder farmers in Uganda. Yet the use of the hand hoe scratches the soil surface leading to soil erosion. Others use cover plants such as mukuna but this is not applicable, especially in cases where the smallholder farmers have to practice intercropping.
“There is a big risk of reducing the population of honey bees and other pollinators due to misuse of agrochemicals by farmers. Even other non-target insects get killed by mindless application of agrochemicals. The issue is made worse by the inability by the farmers to read and understand the literature that comes with the chemicals. The manufacturer recommends a dosage like 20 milligrammes mixed with about 20 litres of water, but many farmers decide to overlook this and instead mix 40 milligrammess with 20 litres out of a desperate desire to quickly finish off the pests. A lot of our farmers in the country don’t follow the manufacturers’ directions when applying the chemicals,” says Godfrey Ssenkaayi, Masaka District entomologist officer.
Careless handling of agrochemicals
He went ahead to refer to the lack of adequate training in handling agrochemicals of the people in many of the shops from where the farmers procure the chemicals. Ssenkaayi further said many farmers fail to observe the number of times the pesticides should be sprayed and the time length between the applications. He remarked that the chemicals are manufactured to kill pests and weeds but if the same chemicals are not properly handled; they can also kill innocent and non-target insects such as honey bees, and other pollinators that are so badly needed for plant propagation and crop production. He is particularly opposed to farmers who spray agrochemicals during the flowering of the plants, saying that it is around that very time that the bees and other pollinators go seeking nectar from the flowers.
“However we cannot fully dismiss the use of agrochemicals as a draw back to the development of our national economy,” Ssenkaayi said. “Trade in agrochemicals provides employment to thousands of people and it is also true that thousands of farmers use the agricultural chemicals carefully and end up with bountiful harvests, which is good for food security and the nation’s economy.”
All living things including human beings can be attacked by diseases which are often cured with the use of chemicals. Just as we cannot avoid visiting hospitals where chemicals are prescribed for us to take, it would be wrong for farmers not to apply chemicals prescribed by agriculturists to save their crops. The health workers always tell the patients how to take the medicines – the dosage – which must be strictly followed. Similarly the farmers have to strictly observe the agrochemicals’ manufacturers instructions on how to apply them on the crops and weeds.
A coffee farmer examines a beehive in his garden. PHOTO/MICHAEL J SSALI
Other factors
Besides careless application of agrochemicals by farmers, Frank Nyanzi, coordinator, Masaka Integrated Bee Producers Association (MIBA) attributes the apparent decline of the population of honey bees and other pollinators, to bush fires and wanton destruction of forests by man to carry out crop production. “The bush and forests are the natural habitat for insects and it is where the bees get pollen and nectar,” he says. “People kill the insects by burning. After destroying their home, where do we expect them to live?”
Eden Kamugisha, a large scale poultry farmer at Kisagazi, Masaka City, who also keeps bees says his target is to have some eight hundred active beehives but he has only succeeded to get bees in only about three hundred hives because as he says there are not enough bees in the area. He attributes the bees' decline to pests, vectors, and predators. He mentions rats, snakes, birds, and lizards.
Diana Namayanja, an insect expert under National Forestry Resources Research Institute (NaFORRI) says there must be strict observance of directions for use of agrochemicals by farmers. “They must know how to mix the chemicals and the frequency of their application.
The agrochemicals are formulated to achieve targeted results like killing particular pests but it has to be borne in mind that there are non-target organisms such as honey bees, some butterflies, and other pollinators that can as well be killed by the same agrochemicals. Besides observing the manufacturers’ instructions the farmers should not apply the chemicals during periods of flowering because that is when most pollinators are busy collecting nectar from the flowers.”
She went on to explain that it is better for the farmers to spray the agrochemicals in the evening when most insects are not active. She said some bees get into contact with the pesticides sprayed on the flowers and they even die when still on their way back to the beehives or wherever they came from. She said that in many instances mindless application of the chemicals on the farm can result in poisoning fish and other organisms in the swamps when it rains and run-off water goes into the valleys.
Namayanja also blames commercialisation of farming as responsible for massive killing of insects including pollinators. “Most large scale farmers find it much cheaper to fight weeds by spraying herbicides,” she said. “They even spray the chemicals when the weeds are flowering and pollinators are busy looking for nectar and pollen.”
In an earlier conversation with Seeds of Gold, Namayanja said, “We have to remember that from time immemorial bees have lived in the wilderness – in the forests and jungles. But we have destroyed their natural habitat which was also their source of nectar and pollen. But if they go out to find nectar and pollen and they land on plants where poisonous chemicals have been sprayed they are bound to take the poison which results in their death.”
According to an article in the online newsletter, Genetic Literacy Project, titled: “Are we facing an insect apocalypse caused by industrial farming and agricultural chemicals? The media says yes; Science says no.” by Jon Entine, researchers at the German Centre for Integrative Biodiversity Research and Martin Luther University observed the following:
Overall terrestrial insects are declining much less rapidly (three to six fold less) than other recent high-profile studies had suggested, and even this likely overstates the trend. Freshwater insect populations are actually increasing. “Crop cover,” which means things such as corn, soybeans, sorghum, cotton, spring and winter wheat, alfalfa and hay, is associated with increases in insect populations.
There is no association between insect population trends and global warming. The only clear association with insect declines is with urbanisation, likely caused by habitat destruction, light pollution and waste pollution.
